#302

AGENTS.md

@@ -106,21 +106,12 @@ npm run preview
 - Explain risks directly.
 - Prefer single quotes for strings unless interpolation or escaping makes
   double quotes better.
-- For Japanese text, follow the 1986 Cabinet Notice
-  《現代仮名遣い》 as the default orthography.
-- For Japanese kanji spelling, do not apply
-  《当用漢字による書きかえ》; prefer the original spelling as the formal one.
 - Ruby: never put a space before method-call parentheses.
-- Ruby: `render` 系メソッド呼び出しでは、keyword 引数付きでも括弧を書かない。
 - Ruby: never put a line break immediately before `)`.
 - Ruby: do not use `%w` or `%i`.
-- In Ruby, when an `if` condition is split across multiple lines and combines
-  clauses with `&&` or `||`, wrap the whole condition in parentheses.
 - Ruby hashes are not blocks; keep `}` on the same line as the final pair.
 - Ruby hashes keep the first pair on the same line as `{` unless line length
   requires a break.
-- Short Ruby hashes may stay visually compact across two lines with the first
-  pair kept on the opening line and aligned continuation pairs below it.
 - Ruby blocks use separate `{ ... }` rules from hashes, with 2-space body
   indentation.
 - For arrays, never put whitespace or a line break immediately before `]`.
@@ -134,97 +125,21 @@ npm run preview
 - TypeScript and TSX use 4-space logical indentation.
 - In TypeScript and TSX only, replace every leading run of 8 spaces with a tab.
 - Tabs are only for leading indentation, never for spaces after non-space text.
-- TypeScript and TSX imports may stay on one line if they remain within the
-  line limit; do not expand short type-only imports mechanically.
-- In TypeScript and TSX, when breaking a line at an operator, break before the
-  operator and put the operator at the beginning of the next line. A trailing
-  operator at end of line is unacceptable. This rule does not apply to Ruby,
-  where it can change the syntactic structure.
-- In TypeScript and TSX, when a function takes one destructured object
-  argument plus an inline type, prefer this shape when it fits locally:
-
-```ts
-const helper = (
-    { value, flag }: { value: string
-		       flag:  boolean },
-): Result => {
-  // ...
-}
-```
-
-- In TypeScript and TSX, put `switch` case block braces on their own lines
-  when a case needs a lexical block:
-
-```ts
-case 'yes':
-case 'no':
-  {
-    const expected = valueFor (item)
-    return expected == null || expected === answer
-  }
-```
-
-- In TypeScript and TSX, use `value == null` and `value != null` as the
-  default nullish checks. Do not use `=== null`, `=== undefined`,
-  `!== null`, or `!== undefined`.
-- If code appears to need a distinction between `null` and `undefined`, treat
-  that as a design smell and revise the logic to avoid the distinction.
-  External library APIs that explicitly require distinguishing the two are the
-  only exception.
-- In TypeScript and TSX, keep short arrays on one line when they fit under the
-  line limit; break arrays only when readability or line length requires it.
-- In TypeScript and TSX, when a ternary expression is split across multiple
-  lines, align `?` and `:` with the condition expression. Do not indent `?` and
-  `:` one extra level under the condition.
-
-```ts
-const value =
-    condition
-    ? consequent
-    : alternate
-```
-
-- In TypeScript and TSX, keep short ternary expressions on one line when they
-  fit cleanly under the line limit.
-- In TypeScript and TSX, prefer ternary expressions for simple conditional
-  value selection. Do not replace a clear ternary with `if` statements, and do
-  not introduce immediately invoked functions just to avoid or reformat a
-  ternary expression.
-- In TypeScript and TSX, do not write `let` followed by later `if` assignments
-  when the value can be expressed as a single `const` initializer. Prefer
-  `const` because it prevents accidental later reassignment.
-- When fixing formatting, change formatting only. Do not change expression
-  structure, control flow, or variable mutability unless the requested style
-  explicitly requires it.
 - Do not add production dependencies without explicit approval.
-- Do not create, modify, or run tests unless the user explicitly asks for
-  test work. When the user asks for tests, keep working and rerun them until
-  they pass or the remaining failure is clearly blocked.
 
 ## Backend rules
 
 - Inspect existing routes, controllers, models, services, and specs before
-  editing backend behaviour.
-- Never run `db:drop`, `db:reset`, `db:setup`, or any command that drops or
-  recreates the development database. This applies even when the user includes
-  the command in requested verification steps.
-- Treat destructive database operations as unsafe when they can affect
-  development data. Ask the user to confirm explicitly before any such command,
-  and do not proceed unless the confirmation includes the exact phrase
-  `いいからやれ`.
-- Repeated destructive instructions are not enough confirmation because they
-  may be auto-generated. Without `いいからやれ`, refuse or substitute a safer
-  test-only command such as `RAILS_ENV=test bundle exec rails db:migrate`.
-- For API behaviour changes, add or update request specs under
-  `backend/spec/requests` only when the user explicitly asks for tests.
+  editing backend behavior.
+- For API behavior changes, add or update request specs under `backend/spec/requests`.
 - Prefer RSpec for new backend tests; existing minitest files under
   `backend/test` do not make minitest the default for new coverage.
 - Do not weaken authentication, BAN user checks, or IP BAN checks.
 - Preserve the `X-Transfer-Code` user identification flow unless the task
   explicitly changes authentication.
 - Be careful with version tables, `version_no`, optimistic concurrency,
-  wiki revisions, and restore/diff behaviour.
-- Be careful with tag names, tag normalisation, implications, similarities, and discard behaviour.
+  wiki revisions, and restore/diff behavior.
+- Be careful with tag names, tag normalization, implications, similarities, and discard behavior.
 - Be sensitive to N+1 queries; avoid introducing them and proactively fix
   existing N+1 issues in the code path being edited.
 - Keep migration files and `backend/db/schema.rb` consistent when changing schema.
@@ -239,116 +154,17 @@ const value =
 - Keep page-level code under `frontend/src/pages` and shared UI/feature code
   under `frontend/src/components` unless existing patterns point elsewhere.
 - Match existing Tailwind, component, and import alias conventions.
-- `<a href="#">` is acceptable for event-only controls when it fits the local
-  UI pattern. Do not use `<a>` for internal navigation or other non-external
-  links.
-- Internal links must use `PrefetchLink`.
-- External links must use `<a>` with `target="_blank"`.
-- When adding or changing Tailwind `bg-*` classes in TSX, pair them with an
-  explicit readable `text-*` colour and dark-mode counterparts such as
-  `dark:bg-*`, `dark:text-*`, and `dark:border-*` where a border is present.
-- Do not rely on inherited text colour for light backgrounds. This is especially
-  important for chips, cards, buttons, and panels that may inherit white text in
-  dark mode.
-- Mobile UI must be checked as a first-class layout. Avoid wide fixed content,
-  make dense controls wrap or scroll intentionally, and keep tag/filter
-  controls usable without horizontal page overflow.
-- For mobile horizontal scrollers, make the scroll direction and item sizing
-  explicit, and ensure chip text remains readable in both light and dark modes.
-- In TypeScript and TSX, prefer direct comparison operators such as `===` and
-  `!==` over negating a comparison like `!(a === b)`.
-- In TypeScript and TSX, prefer `++i` or `--i` over `i += 1` or `i -= 1` for
-  simple unit-step counter updates.
-- For user-facing Japanese text, follow the 1986 Cabinet Notice
-  《現代仮名遣い》 and avoid historical kana spellings unless the task
-  explicitly requires them.
-- For user-facing Japanese kanji spelling, do not normalize to
-  《当用漢字による書きかえ》; prefer original forms such as `編輯`.
-- For user-facing Japanese ellipses, prefer `……` over ASCII `...`.
 
-### Frontend TypeScript and TSX style
+### Frontend TSX style
 
-- The delimiter-placement and line-breaking rules in this section apply to
-  both plain TypeScript `.ts` and TSX `.tsx`, unless a bullet explicitly says
-  it is JSX- or React-specific.
-- Preserve the local TypeScript and TSX formatting style.
+- Preserve the local TSX formatting style.
 - Do not normalize TSX to common Prettier-style React formatting unless
   explicitly asked.
-- Treat TypeScript and TSX formatting rules as hard constraints, not
-  preferences. Before finishing a TypeScript or TSX edit, inspect the edited
-  hunks for closing `)`, `]`, and `}` placement and fix violations instead of
-  relying on formatter defaults.
-- After every TypeScript or TSX edit, perform a style-only self-review of the
-  edited hunks before running verification or reporting completion. The task is
-  not complete while any edited TypeScript or TSX hunk violates these local
-  formatting rules.
-- The TypeScript/TSX self-review must classify every edited leading or trailing
-  `)`, `]`, and `}` by syntax role before deciding whether it is valid. Do not
-  apply a rule by glyph alone. A closing `)` for a function parameter list is
-  different from a closing `)` for a function call. A closing `}` for a block
-  is different from a closing `}` for an object, type literal, import list, or
-  destructuring pattern.
-- The TSX-specific self-review must confirm there are no common Prettier-style
-  React component declarations with a multi-line destructured parameter.
-- The TypeScript/TSX self-review must confirm multi-line function declaration
-  parameter `)` placement follows the detailed parameter-list rules below.
-- The TypeScript/TSX self-review must confirm call-expression `)` is never at
-  the beginning of a line.
-- The TypeScript/TSX self-review must confirm
-  object/type/import/destructuring `}` is not at the beginning of a line.
-- The TypeScript/TSX self-review must confirm multi-line
-  function/lambda/callback/block `}` is on its own line and never at the end
-  of the previous line.
-- The TypeScript/TSX self-review must confirm array `]` is not at the
-  beginning of a line.
-- The TSX-specific self-review must confirm JSX closing markers and closing
-  parentheses keep the surrounding compact style.
-- The TypeScript/TSX self-review must confirm leading indentation follows
-  4-space logical indentation with tabs only as leading 8-space compression.
 - Prefer `const` arrow functions for TypeScript/TSX component and helper declarations.
 - Put two blank lines before and after top-level `const` function
   declarations, unless imports, exports, or file boundaries make that awkward.
 - In TSX, indent with 4-space logical indentation.
-- In TypeScript and TSX, convert every leading run of 8 spaces to a tab
-  character.
 - A leading tab is exactly equivalent to 8 leading spaces.
-- In TypeScript and TSX function declarations, including `const` arrow
-  function declarations, classify the parameter list before placing the closing
-  `)`.
-- If the parameter list itself is given its own multi-line block after the
-  function's opening `(`, put the closing parameter `)` at the beginning of its
-  own line before the return type or `=>`.
-- If the only line break is inside a parameter's inline type, object type, or
-  destructuring shape, and the parameter list itself is not split as a separate
-  block, keep the closing parameter `)` on the same line as that parameter's
-  final `}`. In this case, moving `)` to a new line is wrong.
-- Do not write React component declarations in the common Prettier form
-  `const Component = ({ ... }) => (` when the destructured parameter spans
-  multiple lines. Use the project form with the opening `(` after `=`, the
-  destructured object as the argument, and the closing parameter `)` on its own
-  line before `=>`.
-- In TypeScript and TSX, never place a closing parenthesis at the beginning of
-  a line except for a multi-line function declaration parameter list.
-- Never place a closing square bracket at the beginning of a line.
-- For object literals, type literals, import/export named bindings, destructuring
-  patterns, and other associative-array-style braces, do not place the closing
-  brace at the beginning of a line. Keep `}` on the same line as the final
-  property, binding, or specifier unless that would violate the line limit.
-  Function, lambda, callback, and block closing braces are exempt and should
-  stay on their own line when that fits the local style. When a function,
-  lambda, callback, or block body spans multiple lines, do not put its closing
-  `}` at the end of the previous line.
-- For arrays and tuple-like lists, do not place the closing `]` at the
-  beginning of a line. Keep `]` on the same line as the final element unless
-  that would violate the line limit.
-- For function and method calls, do not place the closing `)` at the beginning
-  of a line. The only TypeScript/TSX exception is the closing parameter `)` of a
-  multi-line function declaration.
-- When writing braces on a single line in TypeScript or TSX JavaScript
-  context, put exactly one space inside the braces, as in `{ value }` or
-  `{ key: value }`.
-- Do not add inner spaces to React/JSX expression braces, as in
-  `prop={value}`, `{children}`, or `<Component>{{...props}}</Component>`.
 - Keep a tag's closing marker on the same line as the final prop when the tag
   spans multiple lines.
 - Do not put `/>` or `>` on its own line unless the existing surrounding code
@@ -359,588 +175,6 @@ const value =
   single physical line.
 - Always add braces around `if`, `else`, or `for` bodies when the body spans
   two or more physical lines, even if it is one statement.
-- Do not use a leading semicolon for expression statements such as
-  `;([...]).forEach(...)`; rewrite the expression to avoid ASI hazards
-  explicitly, for example with `void`.
-- Do not insert `void` mechanically before ordinary event-handler or callback
-  calls merely because the callee returns a `Promise`. If the surrounding code
-  already uses a plain expression statement such as
-  `onClick={() => requestActiveTab ('theme')}`, preserve that style unless a
-  local rule or type requirement truly forces `void`. Adding unnecessary
-  `void` is a medium-severity style violation.
-- When fixing formatting, never change operator binding, evaluation order,
-  tuple/comma behaviour, or any other expression structure. A formatting pass
-  that changes how `!==`, `??`, `?:`, `&&`, `||`, or `,` binds is a capital
-  offence.
-- In TypeScript and TSX, do not mechanically verticalise short call tails,
-  short object literals, or short callback bodies that already fit the local
-  line-length and delimiter rules. Expanding compact local code without a
-  readability need is a minor style violation.
-- In TypeScript and TSX, treat short object literals, short returned objects,
-  short typed object shapes, and short function-call object arguments as
-  compact associative syntax by default. If they fit locally, keep the opening
-  `{` on the same line as the first property and keep the closing `}` on the
-  same line as the final property. Do not explode them into vertical
-  Prettier-style blocks without a concrete readability or line-length reason.
-- In TypeScript and TSX, when a compact associative form is broken across two
-  lines, keep the opening `{` with the first property and the closing `}` with
-  the final property. A shape like `{\n    key: value,\n}` is wrong even when
-  line length would permit it.
-- In TypeScript and TSX, when a short call such as `apiGet<...> (...)`,
-  `apiPatch<...> (...)`, `setState (...)`, `updateClientSettings (...)`, or
-  `window.dispatchEvent (...)` already fits within the local style, do not
-  add extra vertical layers around the object argument or callback body.
-- In TypeScript and TSX, after editing a file, inspect the file tail and
-  remove meaningless blank lines before `export default` or the end of file.
-  A stray empty line before `export default` is a minor style offence.
-- Use correct British English spelling for new identifiers, filenames,
-  component names, helper names, comments, and developer-facing prose unless
-  editing an already established American-English API that must keep its
-  existing spelling for compatibility.
-- Prefer British English spellings such as `behaviour`, `colour`, `realise`,
-  `theatre`, `centre`, `favourite`, `optimise`, and `catalogue`.
-- Avoid American or Canadian spellings such as `behavior`, `color`, `realize`,
-  `theater`, `center`, `favorite`, `optimize`, and `catalog`.
-- Even when an external library or API uses the wrong spelling, prefer to
-  correct it at the local boundary and use proper British English names in this
-  codebase. For example, prefer `import { color: colour } from '@external-lib'`
-  over spreading `color` through local code.
-- Apply the same boundary correction to object destructuring, wrapper helpers,
-  adapter layers, and local variable names when doing so does not break the
-  external contract.
-- For this repository, prefer names such as `BehaviourSettingsSection.tsx`, not
-  `BehaviorSettingsSection.tsx`.
-
-### Additional style offences and penalties
-
-Use this section for recurrent failure modes that are easy to miss when
-applying the delimiter rules mechanically.
-
-#### Unnecessary `void` before ordinary callbacks
-
-Bad:
-
-```ts
-onClick={() => void requestActiveTab ('theme')}
-```
-
-Good:
-
-```ts
-onClick={() => requestActiveTab ('theme')}
-```
-
-Penalty: medium-severity offence. The code still works, but it pollutes the
-local style and usually signals that the edit was made mechanically rather than
-by reading the surrounding code.
-
-#### Formatting that changes expression structure
-
-Bad:
-
-```ts
-const hasUnsavedChanges =
-    serialiseThemeDraft (draftThemeSlots)
-    !== (serialiseThemeDraft (savedThemeSlots),
-	 draftActiveThemeMode !== savedThemeMode)
-```
-
-Good:
-
-```ts
-const hasUnsavedChanges =
-    serialiseThemeDraft (draftThemeSlots)
-    !== serialiseThemeDraft (savedThemeSlots)
-    || draftThemeMode !== savedThemeMode
-```
-
-Penalty: capital offence. Formatting must never corrupt the meaning of an
-expression.
-
-#### Mechanical vertical expansion of compact local code
-
-Bad:
-
-```ts
-const nextState = {
-    open,
-    activeTab }
-
-setDirtyStates (
-    current => ({
-	current,
-	key:  value }),
-)
-```
-
-Good:
-
-```ts
-const nextState = { open, activeTab }
-
-setDirtyStates (
-    current => ({
-	current,
-	key:  value }))
-```
-
-Penalty: minor offence when semantics stay intact. It is not necessarily
-broken, but it ignores the repository's compact associative style.
-
-#### Prettier-style exploded object literals that should stay compact
-
-Bad:
-
-```ts
-const next = {
-    enabled: keyboard?.enabled !== false,
-    bindings: normaliseKeyboardBindings (keyboard?.bindings),
-}
-```
-
-Good:
-
-```ts
-const next = {
-    enabled: keyboard?.enabled !== false,
-    bindings: normaliseKeyboardBindings (keyboard?.bindings) }
-```
-
-Also good when short enough:
-
-```ts
-const next = { enabled: keyboard?.enabled !== false,
-	       bindings: normaliseKeyboardBindings (keyboard?.bindings) }
-```
-
-Rule: for compact associative syntax, keep `{` with the first property and `}`
-with the final property unless line length truly forces a different shape.
-Do not mechanically apply the common Prettier block form.
-Penalty: medium-severity offence. The code still runs, but it violates a core
-repository formatting habit that must be preserved consistently.
-
-#### Exploded object arguments inside short calls
-
-Bad:
-
-```ts
-updateClientSettings (settings => ({
-    ...settings,
-    keyboard: next,
-}))
-```
-
-Good:
-
-```ts
-updateClientSettings (settings => ({
-    ...settings,
-    keyboard: next }))
-```
-
-Rule: a call-expression closing `)` must not drift onto its own line, and a
-short object argument should not be exploded more than necessary. Keep the
-callback's returned object compact when it fits.
-Penalty: medium-severity offence. This usually means the edit was formatted
-mechanically instead of by reading the local style.
-
-#### Stray blank line before `export default`
-
-Bad:
-
-```ts
-const Component: FC = () => {
-  return <div/>
-}
-
-
-export default Component
-```
-
-Good:
-
-```ts
-const Component: FC = () => {
-  return <div/>
-}
-
-export default Component
-```
-
-Rule: do not leave an extra empty line between the last top-level declaration
-and `export default` unless some surrounding file structure genuinely requires
-visual separation.
-Penalty: minor offence. It is small, but it is easy to avoid and should not
-recur.
-
-### Frontend delimiter decision table
-
-Use this table before accepting any edited TypeScript or TSX hunk. The table is
-more authoritative than formatter habit.
-
-#### Import and export named bindings
-
-Bad:
-
-```ts
-import {
-    Button,
-    Card,
-} from '@/components/ui'
-```
-
-Good:
-
-```ts
-import { Button,
-	 Card } from '@/components/ui'
-```
-
-Also acceptable when short:
-
-```ts
-import { Button, Card } from '@/components/ui'
-```
-
-Rule: named-binding `}` is associative-array-style syntax. It must not be alone
-at the beginning of a line. Prefer keeping `{` with the first binding and `}`
-with the final binding when this fits the line limit.
-Penalty: capital offence. This is one of the core associative-brace rules.
-
-#### Type literals
-
-Bad:
-
-```ts
-type Props = {
-    open: boolean
-    onOpenChange: (open: boolean) => void
-}
-```
-
-Good:
-
-```ts
-type Props = {
-    open: boolean
-    onOpenChange: (open: boolean) => void }
-```
-
-Rule: type-literal `}` is not a block close. It must stay on the same line as
-the final property unless that would break the hard line limit.
-Penalty: capital offence. Mistaking a type-literal `}` for a block `}` is one
-of the recurring death-class errors.
-
-#### Object literals
-
-Bad:
-
-```ts
-const value = {
-    open,
-    activeScope,
-}
-```
-
-Good:
-
-```ts
-const value = {
-    open,
-    activeScope }
-```
-
-Bad:
-
-```ts
-const value = useMemo (() => ({
-    open,
-    activeScope,
-}), [open, activeScope])
-```
-
-Good:
-
-```ts
-const value = useMemo (() => ({
-    open,
-    activeScope }), [open, activeScope])
-```
-
-Rule: object-literal `}` is associative-array-style syntax. It must not be on a
-line by itself. Keep it with the final property, and keep call `)` off the
-beginning of a line.
-Penalty: capital offence. Wrong object-literal `}` placement and wrong call
-`)` placement are both death-class violations here.
-
-#### Destructuring parameters
-
-Bad:
-
-```tsx
-const Component: FC<Props> = ({
-    open,
-    onOpenChange,
-}) => {
-  return null
-}
-```
-
-Good:
-
-```tsx
-const Component: FC<Props> = (
-    { open,
-      onOpenChange },
-) => {
-  return null
-}
-```
-
-Rule: when a React component or helper takes a destructured object parameter
-that spans multiple lines, do not use the Prettier-style `= ({ ... }) =>`
-shape. Put the function parameter list on its own lines. The destructuring `}`
-stays with the final binding. The parameter-list `)` is then allowed and
-required at the beginning of its own line.
-Penalty: capital offence. This pattern is a primary source of repeated TSX
-style regressions.
-
-#### Inline typed destructuring parameter
-
-Good:
-
-```ts
-const RouteTransitionWrapper = ({ user, setUser }: {
-    user:     User | null
-    setUser:  Dispatch<SetStateAction<User | null>> }) => {
-  return null
-}
-```
-
-Bad:
-
-```ts
-const RouteTransitionWrapper = ({ user, setUser }: {
-    user:     User | null
-    setUser:  Dispatch<SetStateAction<User | null>>
-}) => {
-  return null
-}
-```
-
-Rule: this is not a separately split parameter-list block. The line break is
-inside the inline type. Keep the type-literal `}` and parameter-list `)` on the
-same line as the final type property.
-Penalty: capital offence. Misclassifying this case means the delimiter review
-has failed at the syntax-role level.
-
-#### Multi-line normal parameter list
-
-Bad:
-
-```ts
-const updateDraft = <Key extends keyof Settings,> (
-    key: Key,
-    value: Settings[Key]) => {
-  return null
-}
-```
-
-Good:
-
-```ts
-const updateDraft = <Key extends keyof Settings,> (
-    key:    Key,
-    value:  Settings[Key],
-) => {
-  return null
-}
-```
-
-Rule: when the parameter list itself is split across multiple parameter lines,
-the closing parameter `)` goes at the beginning of its own line before `=>` or
-the return type.
-Penalty: capital offence. This is the main allowed exception for a leading `)`,
-so getting it wrong destroys the whole rule set.
-
-#### Function and callback blocks
-
-Bad:
-
-```ts
-const handleSave = () => { save ()
-}
-```
-
-Bad:
-
-```ts
-const handleSave = () => {
-  save () }
-```
-
-Good:
-
-```ts
-const handleSave = () => {
-  save ()
-}
-```
-
-Rule: block `}` closes executable code, not associative data. Multi-line
-function, lambda, callback, `if`, `for`, `switch`, and similar block braces
-belong on their own line.
-Penalty: capital offence. Confusing block `}` with associative `}` is a
-death-class delimiter error.
-
-#### Function and method calls
-
-Bad:
-
-```ts
-const value = compute (
-    first,
-    second
-)
-```
-
-Good:
-
-```ts
-const value = compute (
-    first,
-    second)
-```
-
-Rule: call-expression `)` must not be at the beginning of a line. The exception
-for leading `)` applies only to function declaration parameter lists, never to
-calls.
-Penalty: capital offence. A leading call `)` is one of the clearest death-class
-violations in this codebase.
-
-#### JSX closing markers
-
-Bad:
-
-```tsx
-<Button
-    type="button"
-    onClick={handleSave}
->
-  保存
-</Button>
-)
-```
-
-Good:
-
-```tsx
-<Button
-    type="button"
-    onClick={handleSave}>
-  保存
-</Button>)
-```
-
-Bad:
-
-```tsx
-<Input
-    value={value}
-    onChange={handleChange}
-/>
-```
-
-Good:
-
-```tsx
-<Input
-    value={value}
-    onChange={handleChange}/>
-```
-
-Rule: keep `>` or `/>` with the final prop, and keep JSX closing parentheses in
-the local compact form such as `</div>)`.
-Penalty: medium-severity offence. It is usually not semantically broken, but it
-is a conspicuous TSX-style failure.
-
-#### Arrays and tuples
-
-Bad:
-
-```ts
-const items = [
-    first,
-    second,
-]
-```
-
-Good:
-
-```ts
-const items = [
-    first,
-    second]
-```
-
-Good when short:
-
-```ts
-const items = [first, second]
-```
-
-Rule: array and tuple `]` must not be at the beginning of a line. Keep it with
-the final element unless that would break the hard line limit.
-Penalty: capital offence. A leading `]` is forbidden by the same class of hard
-delimiter rule as leading associative `}` and leading call `)`.
-
-#### Single-line braces
-
-Good:
-
-```ts
-const next = { ...current, enabled: true }
-const tag = { id, name }
-```
-
-Bad:
-
-```tsx
-<Component prop={ value }/>
-```
-
-Good:
-
-```tsx
-<Component prop={value}/>
-```
-
-Rule: JavaScript object braces on one line get one inner space. JSX expression
-braces do not get inner spaces.
-Penalty: minor offence. This is not normally semantic breakage, but it still
-counts as a style miss.
-
-#### Final TypeScript/TSX self-review checklist
-
-Before reporting completion after a TypeScript or TSX edit, check the edited
-hunks line by line. Unless a step explicitly mentions JSX, it applies equally
-to `.ts` and `.tsx`:
-
-1. No import/export/type/object/destructuring `}` appears alone at the beginning
-   of a line.
-2. No call-expression `)` appears at the beginning of a line.
-3. Any leading `)` is definitely closing a function declaration parameter list,
-   not a call.
-4. Any parameter-list `)` at the end of a line is valid because the parameter
-   list itself was not split, only an inline type or destructuring shape was.
-5. No array or tuple `]` appears at the beginning of a line.
-6. Multi-line executable block `}` is on its own line.
-7. JSX `>` and `/>` stay with the final prop unless nearby code proves
-   otherwise.
-8. JSX closing parentheses keep the compact local style.
-9. Leading indentation is 4-space logical indentation with tabs used only as
-   leading 8-space compression.
-10. No line has trailing whitespace.
 
 Preferred:
 
@@ -976,12 +210,11 @@ function PostFormTagsArea ({ tags, setTags }: Props) {
 - Do not scan or summarize dependency/generated/runtime directories such as
   `node_modules`, `dist`, `tmp`, `log`, and `storage` unless explicitly needed.
 - Before touching wiki, tag, versioning, BAN, IP BAN, or authentication
-  behaviour, inspect the related request specs and service objects.
-- If frontend code changes, run only non-test verification commands that
-  apply, such as `npm run build` and `npm run lint`. Run `npm run test:run`
-  only when the user explicitly asks for tests.
-- If backend code changes, do not run RSpec unless the user explicitly asks
-  for tests.
+  behavior, inspect the related request specs and service objects.
+- If frontend code changes, run the existing frontend verification commands
+  that apply: `npm run build`, `npm run lint`, and `npm run test:run`.
+- If backend code changes, run the relevant RSpec command; for broad backend
+  changes, run `bundle exec rspec`.
 - If a verification command cannot be run or fails, report the exact command and failure.
 
 ## Completion criteria
@@ -989,8 +222,7 @@ function PostFormTagsArea ({ tags, setTags }: Props) {
 A task is complete only when:
 
 - implementation is complete,
-- relevant non-test verification commands pass, or failures are clearly
-  explained,
+- relevant verification commands pass, or failures are clearly explained,
 - unrelated files are not changed,
 - migrations and schema are consistent when schema changes are made,
-- user-facing behaviour is documented when needed.
+- user-facing behavior is documented when needed.

backend/AGENTS.md

@@ -47,10 +47,6 @@ bundle exec rspec
 
 If a command cannot be run or fails, report the exact command and failure.
 
-Do not create, modify, or run tests unless the user explicitly asks for test
-work. When the user asks for tests, keep working and rerun them until they
-pass or the remaining failure is clearly blocked.
-
 ## Rails structure
 
 - `app/controllers`: API controllers.
@@ -72,23 +68,17 @@ service, representation, and spec.
 - Prefer precise, minimal changes.
 - Use single quotes unless interpolation or escaping makes double quotes better.
 - Do not put a space before Ruby method-call parentheses.
-- For `render`-family method calls, omit parentheses even when passing
-  keyword arguments.
 - Never put a line break immediately before `)` in Ruby.
 - Do not use `%w` or `%i` in new Ruby code.
 - Never write a Ruby line longer than 99 characters.
 - Aim to keep Ruby lines within 79 characters where practical.
 - For small Ruby method definitions that take keyword arguments, match the
   local no-parentheses style when nearby code uses it.
-- When an `if` condition is split across multiple lines and combines clauses
-  with `&&` or `||`, wrap the whole condition in parentheses.
 - Treat Ruby hash `{ ... }` style and Ruby block `{ ... }` style as separate
   rules.
 - Do not format Ruby hashes like Ruby blocks.
 - For Ruby hashes, keep the closing `}` on the same line as the final pair.
 - Keep the first pair on the same line as `{` by default.
-- Short Ruby hashes may stay visually compact across two lines with the first
-  pair kept on the opening line and aligned continuation pairs below it.
 - If the hash would exceed the line limit, break after `{` and indent pairs
   by 4 spaces.
 - Put one logical pair per line when the expression would otherwise become
@@ -126,8 +116,7 @@ service, representation, and spec.
 - `User#banned?` and `IpAddress#banned?` check `banned_at.present?`.
 - Do not weaken BAN or IP BAN behavior.
 - If changing request authentication or controller before actions, add or
-  update request specs covering banned users and banned IP addresses only when
-  the user explicitly asks for tests.
+  update request specs covering banned users and banned IP addresses.
 
 ## RSpec
 
@@ -141,9 +130,8 @@ service, representation, and spec.
 - `AuthHelper#sign_in_as(user)` stubs
   `ApplicationController#current_user`; use it when matching existing
   request spec style.
-- Add or update request specs for API behavior changes only when the user
-  explicitly asks for tests, especially status codes, permissions, response
-  shape, and version conflict behavior.
+- Add or update request specs for API behavior changes, especially status
+  codes, permissions, response shape, and version conflict behavior.
 
 ## Migrations
 
@@ -176,8 +164,7 @@ service, representation, and spec.
   the record `version_no`.
 - Do not update versioned records without considering whether a version snapshot must be created.
 - For optimistic concurrency paths, preserve `base_version_no`, `force`, and
-  `merge` semantics. Cover conflicts in request specs only when the user
-  explicitly asks for tests.
+  `merge` semantics and cover conflicts in request specs.
 
 ## Domain cautions
 

backend/app/controllers/gekanator_games_controller.rb

@@ -1,272 +0,0 @@
-class GekanatorGamesController < ApplicationController
-  def create
-    return head :unauthorized unless current_user
-
-    guessed_post_id = params.require(:guessed_post_id)
-    correct_post_id = params[:correct_post_id].presence
-    answers = params.require(:answers).as_json
-
-    game = GekanatorGame.new(
-        user: current_user,
-        guessed_post_id:,
-        correct_post_id:,
-        won: correct_post_id.present? && guessed_post_id.to_i == correct_post_id.to_i,
-        question_count: answers.length,
-        answers:)
-
-    if game.invalid?
-      render json: { errors: game.errors.full_messages }, status: :unprocessable_entity
-      return
-    end
-
-    learned_example_count = 0
-
-    ActiveRecord::Base.transaction do
-      game.save!
-      learned_example_count = learn_answers_from_game!(game)
-    end
-
-    render json: {
-      id: game.id,
-      learned_example_count:
-    }, status: :created
-  rescue ActiveRecord::RecordInvalid => e
-    render json: { errors: e.record.errors.full_messages }, status: :unprocessable_entity
-  end
-
-  def extra_questions
-    game = find_owned_game
-    return if performed?
-
-    questions =
-        GekanatorQuestion
-        .accepted
-        .includes(:gekanator_question_examples)
-        .where(kind: 'post_similarity', source: 'user_suggested')
-        .to_a
-
-    selected =
-        prioritized_extra_questions(
-            questions,
-            post_id: game.correct_post_id,
-            user: current_user,
-            limit: 6)
-
-    render json: {
-      questions: selected.map { |question| extra_question_json(question) }
-    }
-  end
-
-  def extra_question_answers
-    game = find_owned_game
-    return if performed?
-
-    answer_params = params.require(:answers)
-    if !answer_params.is_a?(Array)
-      return render_validation_error fields: { answers: ['配列で指定してください．'] }
-    end
-
-    answers = answer_params.map { |answer|
-      {
-        question_id: answer.require(:question_id).to_i,
-        answer: answer.require(:answer)
-      }
-    }
-    questions = GekanatorQuestion.where(id: answers.map { _1[:question_id] })
-    question_by_id = questions.index_by(&:id)
-    if questions.length != answers.length
-      return render_validation_error fields: { answers: ['質問が見つかりません．'] }
-    end
-    if questions.any? { |question| question.status != 'accepted' || question.kind != 'post_similarity' }
-      return render_validation_error fields: { answers: ['質問が不正です．'] }
-    end
-
-    ActiveRecord::Base.transaction do
-      answers.each do |item|
-        question = question_by_id[item[:question_id]]
-        example =
-            GekanatorQuestionExample.find_or_initialize_by(
-                gekanator_question: question,
-                post: game.correct_post,
-                user: current_user)
-        example.record_answer!(
-            answer: item[:answer],
-            source: 'post_game_extra',
-            gekanator_game: game)
-        example.save!
-      end
-    end
-
-    render json: { count: answers.length }, status: :created
-  end
-
-  private
-
-  def extra_question_json question
-    {
-      id: question.id,
-      text: question.text,
-      source: question.source,
-      priority_weight: question.priority_weight
-    }
-  end
-
-  def prioritized_extra_questions questions, post_id:, user:, limit:
-    answered_question_ids =
-        GekanatorQuestionExample
-        .where(user:, gekanator_question_id: questions.map(&:id))
-        .distinct
-        .pluck(:gekanator_question_id)
-    unanswered, answered =
-        questions.partition { |question| !answered_question_ids.include?(question.id) }
-    selected = weighted_sample_questions(unanswered, post_id:, limit:)
-    return selected if selected.length >= limit
-
-    selected + weighted_sample_questions(
-        answered.reject { |question| selected.any? { _1.id == question.id } },
-        post_id:,
-        limit: limit - selected.length)
-  end
-
-  def weighted_sample_questions questions, post_id:, limit:
-    remaining = questions.uniq(&:id)
-    selected = []
-
-    while selected.length < limit && remaining.any?
-      weighted =
-          remaining.map { |question|
-            [question, selection_weight_for(question, post_id: post_id)]
-          }
-      total_weight = weighted.sum { |_question, weight| weight }
-      break if total_weight <= 0
-
-      target = rand * total_weight
-      cumulative = 0.0
-      chosen =
-          weighted.find do |_question, weight|
-            cumulative += weight
-            cumulative >= target
-          end&.first || weighted.first.first
-
-      selected << chosen
-      remaining.reject! { |question| question.id == chosen.id }
-    end
-
-    selected
-  end
-
-  def selection_weight_for question, post_id:
-    sample_count =
-        question.gekanator_question_examples.sum { |example|
-          next 0 unless example.post_id == post_id
-
-          example.sample_count.presence || 1
-        }
-
-    question.priority_weight.to_f / (1.0 + sample_count * 0.15)
-  end
-
-  def find_owned_game
-    return head :unauthorized unless current_user
-
-    game = GekanatorGame.find_by(id: params[:id])
-    return head :not_found unless game
-    if !current_user.admin? && game.user_id != current_user.id
-      return head :not_found
-    end
-
-    game
-  end
-
-  def learn_answers_from_game! game
-    correct_post = game.correct_post
-    return 0 if correct_post.blank?
-
-    accepted_questions =
-        GekanatorQuestion
-        .accepted
-        .index_by { |question| public_question_id_for(question) }
-    learned_count = 0
-
-    Array(game.answers).each do |answer|
-      answer_value = answer['answer'].to_s
-      next if answer_value.blank? || answer_value == 'unknown'
-
-      question_id = game_answer_question_id(answer)
-      next if question_id.blank?
-
-      question = accepted_questions[question_id.to_s]
-      next unless learnable_game_answer_question?(question)
-
-      example =
-          GekanatorQuestionExample.find_or_initialize_by(
-              gekanator_question: question,
-              post: correct_post,
-              user: current_user)
-      example.record_answer!(
-          answer: answer_value,
-          source: 'post_game_answer',
-          gekanator_game: game)
-      example.save!
-      learned_count += 1
-    end
-
-    learned_count
-  end
-
-  def public_question_id_for question
-    condition = normalize_condition(question.condition)
-
-    case condition[:type]
-    when 'tag'
-      "tag:#{condition[:key]}"
-    when 'source'
-      "source:#{condition[:host]}"
-    when 'original-year'
-      "original-year:#{condition[:year]}"
-    when 'original-month'
-      "original-month:#{condition[:month]}"
-    when 'original-month-day'
-      "original-month-day:#{condition[:monthDay] || condition[:month_day]}"
-    when 'title-length-at-least'
-      "title:length-at-least:#{condition[:length]}"
-    when 'title-length-greater-than'
-      "title:length-at-least:#{condition[:length].to_i + 1}"
-    when 'title-has-ascii'
-      'title:ascii'
-    when 'title-contains'
-      "title:contains:#{condition[:text]}"
-    when 'post-similarity'
-      "post-similarity:#{question.id}"
-    else
-      "catalog:#{question.id}"
-    end
-  end
-
-  def normalize_condition condition
-    json = condition.deep_dup.as_json
-
-    if json['type'] == 'original-month-day' && json['monthDay'].blank?
-      json['monthDay'] = json.delete('month_day')
-    end
-
-    json.deep_symbolize_keys
-  end
-
-  def learnable_game_answer_question? question
-    return false if question.nil?
-    return true if question.kind == 'post_similarity'
-    return false unless question.kind == 'tag'
-
-    condition = normalize_condition(question.condition)
-    key = condition[:key].to_s
-    !key.start_with?('nico:')
-  end
-
-  def game_answer_question_id answer
-    answer['question_id'] ||
-      answer[:question_id] ||
-      answer['questionId'] ||
-      answer[:questionId]
-  end
-end

backend/app/controllers/gekanator_posts_controller.rb

@@ -1,71 +0,0 @@
-class GekanatorPostsController < ApplicationController
-  def index
-    posts =
-        Post
-        .preload(:post_similarities, tags: :tag_name)
-        .with_attached_thumbnail
-        .order(Arel.sql(
-            'COALESCE(posts.original_created_before - INTERVAL 1 MINUTE, ' \
-            'posts.original_created_from, posts.created_at) DESC, posts.id DESC'))
-        .to_a
-
-    active_tags_by_post_id =
-        posts.each_with_object({ }) do |post, h|
-          h[post.id] = post.tags.reject(&:deprecated?)
-        end
-
-    render json: {
-      posts: posts.map { |post|
-        post_json(post,
-                  active_tags_by_post_id:)
-      }
-    }
-  end
-
-  private
-
-  def post_json post, active_tags_by_post_id:
-    {
-      id: post.id,
-      url: post.url,
-      title: post.title,
-      thumbnail: thumbnail_url(post),
-      thumbnail_base: post.thumbnail_base,
-      original_created_from: post.original_created_from,
-      original_created_before: post.original_created_before,
-      post_similarity_edges: post_similarity_edges_json(
-          post,
-          active_tags_by_post_id:),
-      tags: active_tags_by_post_id.fetch(post.id, []).map { |tag| tag_json(tag) }
-    }
-  end
-
-  def post_similarity_edges_json post, active_tags_by_post_id:
-    post
-        .post_similarities
-        .filter_map do |similarity|
-          next unless active_tags_by_post_id.key?(similarity.target_post_id)
-
-          {
-            target_post_id: similarity.target_post_id,
-            cos: similarity.cos.to_f
-          }
-        end
-  end
-
-  def tag_json tag
-    {
-      id: tag.id,
-      name: tag.name,
-      category: tag.category
-    }
-  end
-
-  def thumbnail_url post
-    return nil unless post.thumbnail.attached?
-
-    rails_storage_proxy_url(post.thumbnail, only_path: false)
-  rescue
-    nil
-  end
-end

backend/app/controllers/gekanator_question_suggestions_controller.rb

@@ -1,95 +0,0 @@
-class GekanatorQuestionSuggestionsController < ApplicationController
-  def create
-    return head :unauthorized unless current_user
-
-    game = GekanatorGame.find_by(id: params.require(:gekanator_game_id))
-    return head :not_found unless game
-    if !current_user.admin? && game.user_id != current_user.id
-      return head :not_found
-    end
-
-    existing_question_id = params[:existing_question_id].presence
-    if existing_question_id
-      question = GekanatorQuestion.accepted.find_by(id: existing_question_id)
-      return head :not_found unless question
-      unless learnable_existing_question?(question)
-        return render_validation_error fields: { existing_question_id: ['質問が不正です．'] }
-      end
-
-      example =
-          GekanatorQuestionExample.find_or_initialize_by(
-              gekanator_question: question,
-              post: game.correct_post,
-              user: current_user)
-      example.record_answer!(
-          answer: params.require(:answer),
-          source: 'post_game_extra',
-          gekanator_game: game)
-
-      if example.save
-        render json: {
-          id: question.id,
-          count: game.question_suggestions.count
-        }, status: :created
-      else
-        render_validation_error example
-      end
-      return
-    end
-
-    suggestion = GekanatorQuestionSuggestion.new(
-        gekanator_game: game,
-        user: current_user,
-        question_text: params.require(:question_text),
-        answer: params.require(:answer))
-
-    if suggestion.valid?
-      ActiveRecord::Base.transaction do
-        suggestion.save!
-        Gekanator::QuestionSuggestionPromoter.call(
-            suggestion: suggestion,
-            user: current_user)
-      end
-
-      render json: {
-        id: suggestion.id,
-        count: game.question_suggestions.count
-      }, status: :created
-    else
-      render_validation_error suggestion
-    end
-  end
-
-  def ai_convert
-    return head :not_found unless current_user&.admin?
-
-    suggestion = GekanatorQuestionSuggestion.find_by(id: params[:id])
-    return head :not_found unless suggestion
-    if Gekanator::AiRunBudget.exceeded_after_next_run?
-      suggestion.gekanator_ai_runs.create!(
-          model: 'budget_guard',
-          status: 'blocked_budget',
-          input_tokens: 0,
-          output_tokens: 0,
-          estimated_cost_jpy: 0)
-      return head :payment_required
-    end
-
-    Gekanator::QuestionSuggestionAiConverter.call(
-        suggestion: suggestion,
-        user: current_user)
-    head :no_content
-  rescue NotImplementedError
-    head :not_implemented
-  end
-
-  private
-
-  def learnable_existing_question? question
-    return true if question.kind == 'post_similarity'
-    return false unless question.kind == 'tag'
-
-    key = question.condition.as_json['key'].to_s
-    !key.start_with?('nico:')
-  end
-end

backend/app/controllers/gekanator_questions_controller.rb

@@ -1,147 +0,0 @@
-class GekanatorQuestionsController < ApplicationController
-  def index
-    questions =
-        GekanatorQuestion
-        .accepted
-        .includes(:gekanator_question_examples)
-        .order(priority_weight: :desc, id: :asc)
-        .to_a
-    deprecated_tag_keys = deprecated_tag_keys_for(questions)
-
-    render json: {
-      questions: questions.filter_map { |question|
-        json = question_json(question)
-        next if hidden_question?(json[:condition], deprecated_tag_keys)
-
-        json
-      }
-    }
-  end
-
-  private
-
-  def question_json question
-    condition = condition_json(question.condition).deep_symbolize_keys
-    json = {
-      record_id: question.id,
-      id: question_id_for(question, condition),
-      text: question_text_for(question, condition),
-      kind: question.kind,
-      condition: condition,
-      source: question.source,
-      priority_weight: question.priority_weight
-    }
-    if question.kind == 'post_similarity' || question.kind == 'tag'
-      json[:example_answers] = example_answers_json(question)
-    end
-    json
-  end
-
-  def question_id_for question, condition
-    case condition[:type]
-    when 'tag'
-      "tag:#{ condition[:key] }"
-    when 'source'
-      "source:#{ condition[:host] }"
-    when 'original-year'
-      "original-year:#{ condition[:year] }"
-    when 'original-month'
-      "original-month:#{ condition[:month] }"
-    when 'original-month-day'
-      "original-month-day:#{ condition[:monthDay] || condition[:month_day] }"
-    when 'title-length-at-least'
-      "title:length-at-least:#{ condition[:length] }"
-    when 'title-length-greater-than'
-      "title:length-at-least:#{ condition[:length].to_i + 1 }"
-    when 'title-has-ascii'
-      'title:ascii'
-    when 'title-contains'
-      "title:contains:#{ condition[:text] }"
-    when 'post-similarity'
-      "post-similarity:#{ question.id }"
-    else
-      "catalog:#{ question.id }"
-    end
-  end
-
-  def condition_json condition
-    json = condition.deep_dup.as_json
-
-    if json['type'] == 'original-month-day' && json['monthDay'].blank?
-      json['monthDay'] = json.delete('month_day')
-    end
-
-    if json['type'] == 'title-length-greater-than'
-      json['type'] = 'title-length-at-least'
-      json['length'] = json['length'].to_i + 1
-    end
-
-    json
-  end
-
-  def question_text_for question, condition
-    return question.text unless question.kind == 'title'
-
-    case condition[:type]
-    when 'title-length-at-least'
-      "タイトルは #{ condition[:length] } 文字以上?"
-    when 'title-contains'
-      "題名に「#{ condition[:text] }」が含まれる?"
-    else
-      question.text
-    end
-  end
-
-  def example_answers_json question
-    question
-        .gekanator_question_examples
-        .group_by(&:post_id)
-        .transform_values { |examples| aggregate_answer(examples) }
-  end
-
-  def aggregate_answer examples
-    examples
-        .group_by(&:answer)
-        .map { |answer, grouped| [answer, grouped.sum(&:weight), grouped.max_by(&:updated_at)&.updated_at] }
-        .sort_by { |(_answer, weight, updated_at)| [-weight, -(updated_at&.to_f || 0)] }
-        .first
-        &.first
-  end
-
-  def deprecated_tag_keys_for questions
-    tag_keys = questions.filter_map { |question|
-      condition = condition_json(question.condition)
-      next unless condition['type'] == 'tag'
-
-      condition['key'].to_s.presence
-    }.uniq
-    return {} if tag_keys.empty?
-
-    categories = []
-    names = []
-    tag_keys.each do |key|
-      category, name = parse_tag_key(key)
-      categories << category
-      names << name
-    end
-
-    Tag
-        .joins(:tag_name)
-        .where(category: categories.uniq)
-        .where(tag_names: { name: names.uniq })
-        .where.not(deprecated_at: nil)
-        .pluck('tags.category', 'tag_names.name')
-        .each_with_object({ }) do |(category, name), h|
-          h["#{ category }:#{ name }"] = true
-        end
-  end
-
-  def hidden_question? condition, deprecated_tag_keys
-    condition[:type] == 'tag' && deprecated_tag_keys[condition[:key].to_s]
-  end
-
-  def parse_tag_key key
-    parts = key.to_s.split(':')
-    [parts.first.to_s, parts.drop(1).join(':')]
-  end
-end

backend/app/controllers/material_sync_suppressions_controller.rb

@@ -1,49 +0,0 @@
-class MaterialSyncSuppressionsController < ApplicationController
-  def index
-    return head :unauthorized unless current_user
-    return head :forbidden unless current_user.gte_member?
-
-    suppressions =
-        MaterialSyncSuppression
-        .includes(:created_by_user)
-        .order(created_at: :desc, id: :desc)
-
-    render json: { suppressions: suppressions.map { |s| repr(s) } }
-  end
-
-  def create
-    return head :unauthorized unless current_user
-    return head :forbidden unless current_user.gte_member?
-
-    suppression =
-        MaterialSyncSuppressionRegistrar.create!(suppression_params,
-                                                 created_by_user: current_user)
-
-    render json: repr(suppression), status: :created
-  rescue ActiveRecord::RecordInvalid => e
-    render_validation_error e.record
-  end
-
-  private
-
-  def suppression_params
-    params.permit(:source_kind,
-                  :source_uri,
-                  :drive_path,
-                  :drive_file_id,
-                  :reason)
-  end
-
-  def repr suppression
-    { id: suppression.id,
-      source_kind: suppression.source_kind,
-      source_uri: suppression.source_uri,
-      drive_path: suppression.drive_path,
-      drive_file_id: suppression.drive_file_id,
-      normalized_source_key: suppression.normalized_source_key,
-      reason: suppression.reason,
-      created_by_user: suppression.created_by_user&.as_json(UserRepr::BASE),
-      created_at: suppression.created_at,
-      updated_at: suppression.updated_at }
-  end
-end

backend/app/controllers/material_versions_controller.rb

@@ -1,54 +0,0 @@
-class MaterialVersionsController < ApplicationController
-  def index
-    page = (params[:page].presence || 1).to_i
-    limit = (params[:limit].presence || 20).to_i
-
-    page = 1 if page < 1
-    limit = 1 if limit < 1
-
-    offset = (page - 1) * limit
-
-    q = MaterialVersion.includes(:created_by_user)
-    q = q.where(material_id: params[:material_id]) if params[:material_id].present?
-    q = q.where(tag_name: params[:tag].to_s.strip) if params[:tag].present?
-    q = q.where(event_type: params[:event_type]) if params[:event_type].present?
-
-    count = q.except(:order, :limit, :offset).count
-    versions =
-        q
-        .order(Arel.sql('material_versions.created_at DESC, material_versions.id DESC'))
-        .limit(limit)
-        .offset(offset)
-
-    render json: { versions: serialise_versions(versions), count: }
-  end
-
-  private
-
-  def serialise_versions rows
-    rows.map do |row|
-      { id: row.id,
-        material_id: row.material_id,
-        version_no: row.version_no,
-        event_type: row.event_type,
-        tag_id: row.tag_id,
-        tag_name: row.tag_name,
-        tag_category: row.tag_category,
-        url: row.url,
-        source_kind: row.source_kind,
-        source_uri: row.source_uri,
-        source_path: row.source_path,
-        source_file_id: row.source_file_id,
-        normalized_source_key: row.normalized_source_key,
-        file_blob_id: row.file_blob_id,
-        file_filename: row.file_filename,
-        file_content_type: row.file_content_type,
-        file_byte_size: row.file_byte_size,
-        file_sha256: row.file_sha256,
-        export_paths_json: row.export_paths_hash,
-        discarded_at: row.discarded_at,
-        created_by_user: row.created_by_user&.as_json(UserRepr::BASE),
-        created_at: row.created_at }
-    end
-  end
-end

backend/app/controllers/materials_controller.rb

@@ -1,11 +1,4 @@
-require 'set'
-
-
 class MaterialsController < ApplicationController
-  rescue_from MaterialZipExporter::EmptyExportError, with: :render_zip_empty
-  rescue_from MaterialZipExporter::DuplicatePathError, with: :render_zip_duplicate_path
-  rescue_from MaterialZipExporter::MissingFileError, with: :render_zip_missing_file
-
   def index
     page = (params[:page].presence || 1).to_i
     limit = (params[:limit].presence || 20).to_i
@@ -15,100 +8,54 @@ class MaterialsController < ApplicationController
 
     offset = (page - 1) * limit
 
-    filters = material_index_filters
-    tag_graph = material_index_tag_graph(filters)
-    q = Material.includes(:material_export_items,
-                          thumbnail_attachment: :blob,
-                          file_attachment: :blob,
-                          tag: :tag_name)
-    q = q.where(tag_id: nil) if filters[:tag_state] == 'untagged'
-    q = q.where.not(tag_id: nil) if filters[:tag_state] == 'tagged'
-    q = apply_material_tag_filter(q, filters, tag_graph)
-    q = q.where('materials.created_at >= ?', filters[:created_from]) if filters[:created_from]
-    q = q.where('materials.created_at <= ?', filters[:created_to]) if filters[:created_to]
-    q = q.where('materials.updated_at >= ?', filters[:updated_from]) if filters[:updated_from]
-    q = q.where('materials.updated_at <= ?', filters[:updated_to]) if filters[:updated_to]
+    tag_id = params[:tag_id].presence
+    parent_id = params[:parent_id].presence
 
-    q = material_index_join_tag_name(q) if material_index_needs_tag_name?(filters)
-    q = material_index_join_file_blob(q) if material_index_needs_file_blob?(filters)
-    q = apply_material_query(q, filters[:q]) if filters[:q].present?
-    q = apply_material_media_kind(q, filters[:media_kind])
+    q = Material.includes(:tag, :created_by_user).with_attached_file
+    q = q.where(tag_id:) if tag_id
+    q = q.where(parent_id:) if parent_id
 
-    count = q.distinct.count(:id)
-    materials =
-        q
-        .order(Arel.sql(material_index_order_sql(filters)))
-        .limit(limit)
-        .offset(offset)
-        .to_a
+    count = q.count
+    materials = q.order(created_at: :desc, id: :desc).limit(limit).offset(offset)
 
-    response = { materials: MaterialRepr.list_many(materials, host: request.base_url),
-                 count: }
-    if filters[:tag_id]
-      response[:tag_scope] = material_index_tag_scope(filters, tag_graph)
-    end
-    if filters[:group_by] == 'parent_tag'
-      response[:groups] = material_index_groups(materials, tag_graph)
-    end
-
-    render json: response
+    render json: { materials: MaterialRepr.many(materials, host: request.base_url), count: count }
   end
 
   def show
     material =
         Material
-        .includes(:tag, :material_export_items)
-        .with_attached_thumbnail
+        .includes(:tag)
         .with_attached_file
         .find_by(id: params[:id])
     return head :not_found unless material
 
-    wiki_page_body = material.tag&.tag_name&.wiki_page&.current_revision&.body
+    wiki_page_body = material.tag.tag_name.wiki_page&.current_revision&.body
 
     render json: MaterialRepr.base(material, host: request.base_url).merge(wiki_page_body:)
   end
 
   def create
     return head :unauthorized unless current_user
-    return head :forbidden unless current_user.gte_member?
 
     tag_name_raw = params[:tag].to_s.strip
     file = params[:file]
-    file_sha256 = MaterialFileSha256.from_upload(file)
     url = params[:url].to_s.strip.presence
     return render_unprocessable_entity('タグは必須です．', field: :tag) if tag_name_raw.blank?
     if file.blank? && url.blank?
       return render_validation_error fields: { file: ['ファイルまたは URL は必須です．'],
                                                url: ['ファイルまたは URL は必須です．'] }
     end
-    block = MaterialImportBlockMatcher.match_for_sha256(file_sha256)
-    return render_material_import_block(block) if block
 
-    uploaded_blob = build_uploaded_material_blob!(file, file_sha256)
-    material = nil
+    tag_name = TagName.find_undiscard_or_create_by!(name: tag_name_raw)
+    tag = tag_name.tag
+    tag = Tag.create!(tag_name:, category: :material) unless tag
 
-    begin
-      Material.transaction do
-        tag_name = TagName.find_undiscard_or_create_by!(name: tag_name_raw)
-        tag = tag_name.tag
-        tag = Tag.create!(tag_name:, category: :material) unless tag
+    material = Material.new(tag:, url:,
+                            created_by_user: current_user,
+                            updated_by_user: current_user)
+    material.file.attach(file)
 
-        material = Material.new(tag:, url:,
-                                created_by_user: current_user,
-                                updated_by_user: current_user)
-        material.file.attach(uploaded_blob) if uploaded_blob
-        material.save!
-        upsert_export_paths!(material)
-        MaterialVersionRecorder.record!(material:, event_type: :create,
-                                        created_by_user: current_user)
-      end
-    rescue StandardError
-      uploaded_blob&.purge_later
-      raise
-    end
-
-    if material
-      log_thumbnail_generation(material, MaterialThumbnailGenerator.generate!(material))
+    if material.save
       render json: MaterialRepr.base(material, host: request.base_url), status: :created
     else
       render_validation_error material
@@ -124,44 +71,29 @@ class MaterialsController < ApplicationController
 
     tag_name_raw = params[:tag].to_s.strip
     file = params[:file]
-    file_sha256 = MaterialFileSha256.from_upload(file)
-    url = params.key?(:url) ? params[:url].to_s.strip.presence : material.url
+    url = params[:url].to_s.strip.presence
     return render_unprocessable_entity('タグは必須です．', field: :tag) if tag_name_raw.blank?
-    if file.blank? && url.blank? && !material.file.attached?
+    if file.blank? && url.blank?
       return render_validation_error fields: { file: ['ファイルまたは URL は必須です．'],
                                                url: ['ファイルまたは URL は必須です．'] }
     end
-    block = MaterialImportBlockMatcher.match_for_sha256(file_sha256)
-    return render_material_import_block(block) if block
 
-    uploaded_blob = build_uploaded_material_blob!(file, file_sha256)
+    tag_name = TagName.find_undiscard_or_create_by!(name: tag_name_raw)
+    tag = tag_name.tag
+    tag = Tag.create!(tag_name:, category: :material) unless tag
 
-    begin
-      Material.transaction do
-        MaterialVersionRecorder.ensure_snapshot!(material, created_by_user: current_user)
-        tag_name = TagName.find_undiscard_or_create_by!(name: tag_name_raw)
-        tag = tag_name.tag
-        tag = Tag.create!(tag_name:, category: :material) unless tag
-
-        material.assign_attributes(tag:, url:, updated_by_user: current_user)
-        if uploaded_blob
-          material.file.attach(uploaded_blob)
-        elsif params.key?(:url) && url.present? && file.blank?
-          material.file.detach
-        end
-        material.save!
-        upsert_export_paths!(material)
-        MaterialVersionRecorder.record!(material:, event_type: :update,
-                                        created_by_user: current_user)
-      end
-    rescue StandardError
-      uploaded_blob&.purge_later
-      raise
+    material.update!(tag:, url:, updated_by_user: current_user)
+    if file
+      material.file.attach(file)
+    else
+      material.file.purge
     end
 
-    log_thumbnail_generation(material, MaterialThumbnailGenerator.generate!(material))
-
-    render json: MaterialRepr.base(material, host: request.base_url)
+    if material.save
+      render json: MaterialRepr.base(material, host: request.base_url)
+    else
+      render_validation_error material
+    end
   end
 
   def destroy
@@ -171,375 +103,7 @@ class MaterialsController < ApplicationController
     material = Material.find_by(id: params[:id])
     return head :not_found unless material
 
-    Material.transaction do
-      MaterialVersionRecorder.ensure_snapshot!(material, created_by_user: current_user)
-      material.discard!
-      MaterialVersionRecorder.record!(material:, event_type: :discard,
-                                      created_by_user: current_user)
-    end
+    material.discard
     head :no_content
   end
-
-  def download
-    zip = MaterialZipExporter.new(profile: params[:profile],
-                                  tag_id: params[:tag_id]).export
-    profile = params[:profile].presence || 'legacy_drive'
-    send_data zip,
-              type: 'application/zip',
-              disposition: 'attachment',
-              filename: "btrc-materials-#{ profile }.zip"
-  end
-
-  private
-
-  def material_index_filters
-    tag_state = params[:tag_state].to_s.presence
-    tag_state = 'untagged' if bool?(:unclassified)
-    tag_state = 'all' unless ['all', 'tagged', 'untagged'].include?(tag_state)
-
-    media_kind = params[:media_kind].to_s.presence
-    unless ['all', 'image', 'video', 'audio', 'file_other', 'url_only'].include?(media_kind)
-      media_kind = 'all'
-    end
-
-    sort = params[:sort].to_s.presence
-    unless ['created_at', 'updated_at', 'tag_name', 'media_kind', 'file_byte_size',
-            'version_no', 'id'].include?(sort)
-      sort = 'created_at'
-    end
-
-    direction = params[:direction].to_s.downcase
-    direction = 'desc' unless ['asc', 'desc'].include?(direction)
-
-    group_by = params[:group_by].to_s.presence
-    group_by = 'none' unless ['none', 'parent_tag'].include?(group_by)
-
-    tag_id = params[:tag_id].to_i
-    tag_id = nil if tag_id <= 0
-
-    { q: params[:q].to_s.strip.presence,
-      tag_state:,
-      media_kind:,
-      tag_id:,
-      include_descendants: bool?(:include_descendants),
-      group_by:,
-      created_from: parse_time_param(:created_from),
-      created_to: parse_time_param(:created_to),
-      updated_from: parse_time_param(:updated_from),
-      updated_to: parse_time_param(:updated_to),
-      sort:,
-      direction: }
-  end
-
-  def parse_time_param name
-    value = params[name].to_s.strip
-    return nil if value.blank?
-
-    Time.zone.parse(value)
-  rescue ArgumentError
-    nil
-  end
-
-  def material_index_needs_tag_name? filters
-    filters[:q].present? || filters[:sort] == 'tag_name'
-  end
-
-  def material_index_needs_file_blob? filters
-    filters[:q].present? ||
-        filters[:media_kind] != 'all' ||
-        ['media_kind', 'file_byte_size'].include?(filters[:sort])
-  end
-
-  def material_index_join_tag_name q
-    q.left_joins(tag: :tag_name)
-  end
-
-  def material_index_join_file_blob q
-    q.joins(<<~SQL.squish)
-      LEFT JOIN active_storage_attachments material_file_attachments
-        ON material_file_attachments.record_type = 'Material'
-       AND material_file_attachments.record_id = materials.id
-       AND material_file_attachments.name = 'file'
-      LEFT JOIN active_storage_blobs material_file_blobs
-        ON material_file_blobs.id = material_file_attachments.blob_id
-    SQL
-  end
-
-  def apply_material_query q, term
-    like = "%#{ ActiveRecord::Base.sanitize_sql_like(term) }%"
-    q.where('tag_names.name LIKE :q OR materials.url LIKE :q OR ' \
-            'material_file_blobs.filename LIKE :q',
-            q: like)
-  end
-
-  def apply_material_media_kind q, media_kind
-    case media_kind
-    when 'image'
-      q.where('material_file_blobs.content_type LIKE ?', 'image/%')
-    when 'video'
-      q.where('material_file_blobs.content_type LIKE ?', 'video/%')
-    when 'audio'
-      q.where('material_file_blobs.content_type LIKE ?', 'audio/%')
-    when 'file_other'
-      q.where('material_file_attachments.id IS NOT NULL')
-       .where.not('material_file_blobs.content_type LIKE ?', 'image/%')
-       .where.not('material_file_blobs.content_type LIKE ?', 'video/%')
-       .where.not('material_file_blobs.content_type LIKE ?', 'audio/%')
-    when 'url_only'
-      q.where('material_file_attachments.id IS NULL').where.not(url: [nil, ''])
-    else
-      q
-    end
-  end
-
-  def apply_material_tag_filter q, filters, tag_graph
-    return q unless filters[:tag_id]
-
-    tag_ids =
-        if tag_graph
-          tag_graph[:scope_tag_ids]
-        else
-          [filters[:tag_id]]
-        end
-
-    q.where(tag_id: tag_ids)
-  end
-
-  def material_index_tag_graph filters
-    return nil unless filters[:tag_id]
-
-    children_by_parent_id = Hash.new { |h, k| h[k] = [] }
-    TagImplication.pluck(:parent_tag_id, :tag_id).each do |parent_id, child_id|
-      children_by_parent_id[parent_id] << child_id
-    end
-
-    scope_tag_ids =
-        if filters[:include_descendants]
-          collect_material_descendant_ids(filters[:tag_id], children_by_parent_id)
-        else
-          Set.new([filters[:tag_id]])
-        end
-    tags_by_id =
-        Tag
-        .joins(:tag_name)
-        .where(id: scope_tag_ids)
-        .pluck('tags.id', 'tag_names.name', 'tags.category', 'tags.deprecated_at')
-        .each_with_object({ }) do |(id, name, category, deprecated_at), hash|
-          hash[id] = { id:, name:, category:, deprecated: deprecated_at.present? }
-        end
-
-    selected_tag = tags_by_id[filters[:tag_id]]
-    return nil unless selected_tag
-
-    group_tag_id_by_tag_id = { }
-    children_by_parent_id[filters[:tag_id]].each do |child_tag_id|
-      assign_material_group_branch(child_tag_id,
-                                   children_by_parent_id:,
-                                   tags_by_id:,
-                                   group_tag_id_by_tag_id:,
-                                   current_group_tag_id: nil,
-                                   seen: Set.new([filters[:tag_id]]))
-    end
-
-    { selected_tag_id: filters[:tag_id],
-      selected_tag:,
-      scope_tag_ids: scope_tag_ids.to_a,
-      tags_by_id:,
-      group_tag_id_by_tag_id: }
-  end
-
-  def collect_material_descendant_ids selected_tag_id, children_by_parent_id
-    ids = Set.new([selected_tag_id])
-    stack = [selected_tag_id]
-
-    until stack.empty?
-      tag_id = stack.pop
-      children_by_parent_id[tag_id].each do |child_tag_id|
-        next if ids.include?(child_tag_id)
-
-        ids << child_tag_id
-        stack << child_tag_id
-      end
-    end
-
-    ids
-  end
-
-  def assign_material_group_branch tag_id, children_by_parent_id:, tags_by_id:,
-                                   group_tag_id_by_tag_id:, current_group_tag_id:, seen:
-    return if seen.include?(tag_id)
-
-    tag = tags_by_id[tag_id]
-    return unless tag
-
-    seen = seen.dup << tag_id
-    next_group_tag_id = current_group_tag_id
-    next_group_tag_id = tag_id if next_group_tag_id.nil? && !tag[:deprecated]
-    group_tag_id_by_tag_id[tag_id] = next_group_tag_id if next_group_tag_id
-
-    children_by_parent_id[tag_id].each do |child_tag_id|
-      assign_material_group_branch(child_tag_id,
-                                   children_by_parent_id:,
-                                   tags_by_id:,
-                                   group_tag_id_by_tag_id:,
-                                   current_group_tag_id: next_group_tag_id,
-                                   seen:)
-    end
-  end
-
-  def material_index_groups materials, tag_graph
-    return [] unless tag_graph
-
-    groups_by_key = { }
-
-    materials.each do |material|
-      next unless material.tag_id
-
-      group_tag_id =
-          if material.tag_id == tag_graph[:selected_tag_id]
-            tag_graph[:selected_tag_id]
-          else
-            tag_graph[:group_tag_id_by_tag_id][material.tag_id] || tag_graph[:selected_tag_id]
-          end
-
-      group_tag = tag_graph[:tags_by_id][group_tag_id]
-      next unless group_tag
-
-      key = "tag:#{ group_tag_id }"
-      group =
-          groups_by_key[key] ||= { key:,
-                                   tag: group_tag_repr(group_tag),
-                                   material_ids: [],
-                                   count: 0 }
-      group[:material_ids] << material.id
-      group[:count] += 1
-    end
-
-    groups_by_key.values.sort_by { |group| group[:tag][:name] }
-  end
-
-  def material_index_tag_scope filters, tag_graph
-    return nil unless tag_graph
-
-    {
-      tag: group_tag_repr(tag_graph[:selected_tag]),
-      include_descendants: filters[:include_descendants]
-    }
-  end
-
-  def group_tag_repr group_tag
-    { id: group_tag[:id],
-      name: group_tag[:name],
-      category: group_tag[:category] }
-  end
-
-  def material_index_order_sql filters
-    direction = filters[:direction] == 'asc' ? 'ASC' : 'DESC'
-    sort_sql =
-        case filters[:sort]
-        when 'tag_name'
-          'tag_names.name'
-        when 'media_kind'
-          material_media_kind_sql
-        when 'file_byte_size'
-          'material_file_blobs.byte_size'
-        when 'updated_at'
-          'materials.updated_at'
-        when 'version_no'
-          'materials.version_no'
-        when 'id'
-          'materials.id'
-        else
-          'materials.created_at'
-        end
-
-    "#{ sort_sql } #{ direction }, materials.id #{ direction }"
-  end
-
-  def material_media_kind_sql
-    "CASE " \
-      "WHEN material_file_attachments.id IS NULL AND materials.url IS NOT NULL THEN 5 " \
-      "WHEN material_file_blobs.content_type LIKE 'image/%' THEN 1 " \
-      "WHEN material_file_blobs.content_type LIKE 'video/%' THEN 2 " \
-      "WHEN material_file_blobs.content_type LIKE 'audio/%' THEN 3 " \
-      "WHEN material_file_attachments.id IS NOT NULL THEN 4 " \
-      "ELSE 6 END"
-  end
-
-  def upsert_export_paths! material
-    raw = params[:export_paths]
-    return if raw.blank?
-
-    export_paths = raw.respond_to?(:to_unsafe_h) ? raw.to_unsafe_h : raw.to_h
-    export_paths.each do |profile, export_path|
-      profile = profile.to_s
-      export_path = export_path.to_s.strip
-      item = material.material_export_items.find_or_initialize_by(profile:)
-
-      if export_path.blank?
-        item.destroy! if item.persisted?
-        next
-      end
-
-      item.export_path = export_path
-      item.enabled = true
-      item.created_by_user ||= current_user
-      item.save!
-    end
-  end
-
-  def render_zip_empty
-    render_unprocessable_entity('ZIP export 対象の素材がありません．')
-  end
-
-  def render_zip_duplicate_path error
-    render_unprocessable_entity("ZIP export path が重複してゐます: #{ error.message }")
-  end
-
-  def render_zip_missing_file error
-    missing_files = error.missing_files.map do |missing_file|
-      { material_id: missing_file.material_id,
-        export_path: missing_file.export_path,
-        blob_id: missing_file.blob_id,
-        filename: missing_file.filename }
-    end
-
-    render json: { type: 'validation_error',
-                   message: 'ZIP export に必要な素材ファイルが欠損しています．',
-                   errors: { },
-                   base_errors: ['ZIP export に必要な素材ファイルが欠損しています．'],
-                   missing_files: },
-           status: :unprocessable_entity
-  end
-
-  def build_uploaded_material_blob! file, file_sha256
-    return nil unless file
-
-    file.tempfile.rewind
-
-    blob = ActiveStorage::Blob.create_and_upload!(
-        io: file.tempfile,
-        filename: file.original_filename,
-        content_type: file.content_type,
-    )
-
-    MaterialFileSha256.assign_metadata_sha256!(blob, file_sha256)
-
-    blob
-  ensure
-    file.tempfile.rewind if file&.tempfile
-  end
-
-  def render_material_import_block block
-    render_validation_error fields: { file: ["抑止された素材です: #{ block.reason }"] }
-  end
-
-  def log_thumbnail_generation material, result
-    material.reload
-    Rails.logger.info(
-        "Material thumbnail generation: material_id=#{ material.id } " \
-        "result=#{ result } " \
-        "thumbnail_attached=#{ material.thumbnail.attached? } " \
-        "content_type=#{ material.content_type }")
-  end
 end

backend/app/controllers/post_versions_controller.rb

@@ -25,7 +25,6 @@ class PostVersionsController < ApplicationController
         SQL
         .select('post_versions.*', 'prev.title AS prev_title', 'prev.url AS prev_url',
                 'prev.thumbnail_base AS prev_thumbnail_base', 'prev.tags AS prev_tags',
-                'prev.video_ms AS prev_video_ms',
                 'prev.original_created_from AS prev_original_created_from',
                 'prev.original_created_before AS prev_original_created_before')
     q = q.where('post_versions.post_id = ?', post_id) if post_id
@@ -75,10 +74,6 @@ class PostVersionsController < ApplicationController
           current: row.thumbnail_base,
           prev: row.attributes['prev_thumbnail_base']
         },
-        video_ms: {
-          current: row.video_ms,
-          prev: row.attributes['prev_video_ms']
-        },
         tags: build_version_tags(cur_tags, prev_tags),
         original_created_from: {
           current: row.original_created_from&.iso8601,

backend/app/controllers/posts_controller.rb

@@ -1,10 +1,6 @@
 class PostsController < ApplicationController
   Event = Struct.new(:post, :tag, :user, :change_type, :timestamp, keyword_init: true)
 
-  class VideoMsParseError < ArgumentError
-    ;
-  end
-
   def index
     url = params[:url].presence
     title = params[:title].presence
@@ -49,9 +45,7 @@ class PostsController < ApplicationController
         .joins("LEFT JOIN (#{ pt_max_sql }) pt_max ON pt_max.post_id = posts.id")
         .reselect('posts.*', Arel.sql("#{ updated_at_all_sql } AS updated_at_all"))
         .preload(:uploaded_user, :parents, :children,
-                 active_post_tags: [:sections,
-                                    { tag: [:deerjikists, :materials,
-                                            { tag_name: :wiki_page }] }])
+                 tags: [:deerjikists, :materials, { tag_name: :wiki_page }])
         .with_attached_thumbnail
 
     q = q.where('posts.url LIKE ?', "%#{ url }%") if url
@@ -103,9 +97,7 @@ class PostsController < ApplicationController
 
   def random
     post = filtered_posts.preload(:uploaded_user, :parents, :children,
-                                  active_post_tags: [:sections,
-                                                     { tag: [:deerjikists, :materials,
-                                                             { tag_name: :wiki_page }] }])
+                                  tags: [:deerjikists, :materials, { tag_name: :wiki_page }])
                          .with_attached_thumbnail
                          .order('RAND()')
                          .first
@@ -118,9 +110,7 @@ class PostsController < ApplicationController
     post =
         Post
         .includes(:uploaded_user, :parents, :children,
-                  active_post_tags: [:sections,
-                                     { tag: [:deerjikists, :materials,
-                                             { tag_name: :wiki_page }] }])
+                  tags: [:deerjikists, :materials, { tag_name: :wiki_page }])
         .with_attached_thumbnail
         .find_by(id: params[:id])
     return head :not_found unless post
@@ -135,7 +125,7 @@ class PostsController < ApplicationController
                                  child_posts:,
                                  sibling_posts:,
                                  related:)
-                         .merge(tags: build_tag_tree_for(post))
+                         .merge(tags: build_tag_tree_for(post.tags))
   end
 
   def create
@@ -150,27 +140,24 @@ class PostsController < ApplicationController
     original_created_from = params[:original_created_from]
     original_created_before = params[:original_created_before]
     parent_post_ids = parse_parent_post_ids
-    resized_thumbnail = thumbnail.present? ? Post.resized_thumbnail_attachment(thumbnail) : nil
 
     post = Post.new(title:, url:, thumbnail_base: nil, uploaded_user: current_user,
                     original_created_from:, original_created_before:)
-    post.thumbnail.attach(resized_thumbnail) if resized_thumbnail
+    post.thumbnail.attach(thumbnail) if thumbnail.present?
 
     ApplicationRecord.transaction do
       post.save!
 
-      Tag.normalise_tags!(tag_names, deny_deprecated: true, with_sections: true) =>
-          { tags:, sections: }
+      tags = Tag.normalise_tags!(tag_names)
       TagVersioning.record_tag_snapshots!(tags, created_by_user: current_user)
 
-      tags = Tag.expand_parent_tags(tags).reject(&:deprecated?)
-      post.video_ms = normalise_video_ms(tags)
-      validate_video_sections!(post.video_ms, sections)
-      post.save!
-      sync_post_tags!(post, tags, sections)
+      tags = Tag.expand_parent_tags(tags)
+      sync_post_tags!(post, tags)
 
       sync_parent_posts!(post, parent_post_ids)
 
+      post.resized_thumbnail!
+
       PostVersionRecorder.record!(post:, event_type: :create, created_by_user: current_user)
     end
 
@@ -178,14 +165,6 @@ class PostsController < ApplicationController
     render json: PostRepr.base(post), status: :created
   rescue Tag::NicoTagNormalisationError
     render_validation_error fields: { tags: 'ニコニコ・タグは直接指定できません．' }
-  rescue Tag::DeprecatedTagNormalisationError
-    render_unprocessable_entity '廃止済みタグは付与できません．', field: :tags
-  rescue Tag::SectionLiteralParseError
-    render_validation_error fields: { tags: ['タグ区間の記法が不正です．'] }
-  rescue VideoMsParseError
-    render_validation_error fields: { video_ms: ['動画時間の記法が不正です．'] }
-  rescue MiniMagick::Error
-    render_validation_error fields: { thumbnail: ['サムネイル画像の変換に失敗しました．'] }
   rescue ArgumentError => e
     render_validation_error fields: { parent_post_ids: [e.message] }
   rescue ActiveRecord::RecordInvalid => e
@@ -242,8 +221,6 @@ class PostsController < ApplicationController
                                                  original_created_from:,
                                                  original_created_before:,
                                                  tag_names:,
-                                                 video_ms_param: params[:video_ms],
-                                                 duration_param: params[:duration],
                                                  parent_post_ids:)
 
       snapshot_to_apply =
@@ -274,16 +251,10 @@ class PostsController < ApplicationController
 
     post.reload
     json = PostRepr.base(post, current_user)
-    json['tags'] = build_tag_tree_for(post)
+    json['tags'] = build_tag_tree_for(post.tags)
     render json:, status: :ok
   rescue Tag::NicoTagNormalisationError
     render_validation_error fields: { tags: ['ニコニコ・タグは直接指定できません．'] }
-  rescue Tag::DeprecatedTagNormalisationError
-    render_unprocessable_entity '廃止済みタグは付与できません．', field: :tags
-  rescue Tag::SectionLiteralParseError
-    render_validation_error fields: { tags: ['タグ区間の記法が不正です．'] }
-  rescue VideoMsParseError
-    render_validation_error fields: { video_ms: ['動画時間の記法が不正です．'] }
   rescue ArgumentError => e
     render_validation_error fields: { parent_post_ids: [e.message] }
   rescue ActiveRecord::RecordInvalid => e
@@ -382,7 +353,7 @@ class PostsController < ApplicationController
   def tagged_post_ids_for(name) =
       Post.joins(tags: :tag_name).where(tag_names: { name: }).select(:id)
 
-  def sync_post_tags! post, desired_tags, sections
+  def sync_post_tags! post, desired_tags
     desired_tags.each do |t|
       t.save! if t.new_record?
     end
@@ -401,21 +372,13 @@ class PostsController < ApplicationController
       end
     end
 
-    PostTagSection.where(post_id: post.id).destroy_all
-    sections.each do |tag_id, ranges|
-      ranges.each do |begin_ms, end_ms|
-        PostTagSection.create!(post_id: post.id, tag_id:, begin_ms:, end_ms:)
-      end
-    end
-
     PostTag.where(post_id: post.id, tag_id: to_remove.to_a).kept.find_each do |pt|
       pt.discard_by!(current_user)
     end
   end
 
-  def build_tag_tree_for post
-    post_tags = post.active_post_tags.reject { |post_tag| post_tag.tag.deprecated? }
-    tags = post_tags.map(&:tag)
+  def build_tag_tree_for tags
+    tags = tags.to_a
     tag_ids = tags.map(&:id)
 
     implications = TagImplication.where(parent_tag_id: tag_ids, tag_id: tag_ids)
@@ -430,9 +393,6 @@ class PostsController < ApplicationController
     root_ids = tag_ids - child_ids
 
     tags_by_id = tags.index_by(&:id)
-    sections_by_tag_id = post_tags.to_h { |post_tag|
-      [post_tag.tag_id, post_tag.sections.as_json(only: [:begin_ms, :end_ms])]
-    }
 
     memo = { }
 
@@ -440,10 +400,8 @@ class PostsController < ApplicationController
       tag = tags_by_id[tag_id]
       return nil unless tag
 
-      sections = sections_by_tag_id.fetch(tag_id, [])
-
       if path.include?(tag_id)
-        return TagRepr.inline(tag).merge(children: [], sections:)
+        return TagRepr.inline(tag).merge(children: [])
       end
 
       if memo.key?(tag_id)
@@ -455,7 +413,7 @@ class PostsController < ApplicationController
 
       children = child_ids.filter_map { |cid| build_node.(cid, new_path) }
 
-      memo[tag_id] = TagRepr.inline(tag).merge(children:, sections:)
+      memo[tag_id] = TagRepr.inline(tag).merge(children:)
     end
 
     root_ids.filter_map { |id| build_node.call(id, []) }
@@ -524,7 +482,6 @@ class PostsController < ApplicationController
 
   def post_snapshot_from_version version
     { title: version.title,
-      video_ms: version.respond_to?(:video_ms) ? version.video_ms : nil,
       original_created_from: snapshot_time(version.original_created_from),
       original_created_before: snapshot_time(version.original_created_before),
       tag_names: editable_tag_names_from_version(version),
@@ -537,7 +494,6 @@ class PostsController < ApplicationController
 
   def post_snapshot_from_record post
     { title: post.title,
-      video_ms: post.video_ms,
       original_created_from: snapshot_time(post.original_created_from),
       original_created_before: snapshot_time(post.original_created_before),
       tag_names: editable_tag_names_from_post(post),
@@ -545,41 +501,15 @@ class PostsController < ApplicationController
   end
 
   def editable_tag_names_from_post post
-    post
-        .post_tags
-        .kept
-        .joins(tag: :tag_name)
-        .merge(Tag.not_nico)
-        .merge(Tag.where(deprecated_at: nil))
-        .includes(:sections, tag: :tag_name)
-        .order('tag_names.name')
-        .map do |post_tag|
-      name = post_tag.tag.tag_name.name
-      sections = post_tag.sections.sort_by(&:begin_ms)
-
-      next name if sections.empty?
-
-      "#{ name }#{ sections.map { Post.section_literal(_1) }.join }"
-    end
+    post.tags.not_nico.joins(:tag_name).order('tag_names.name').pluck('tag_names.name')
   end
 
   def post_incoming_snapshot title:, original_created_from:, original_created_before:,
-                             tag_names:, video_ms_param:, duration_param:, parent_post_ids:
-    Tag.normalise_tags!(tag_names, with_tagme: false, deny_deprecated: true,
-                                        with_sections: true) =>
-        { tags:, sections: }
-
-    tags = Tag.expand_parent_tags(tags).reject(&:deprecated?)
-    video_ms = normalise_video_ms(tags, video_ms_param:, duration_param:)
-    validate_video_sections!(video_ms, sections)
-
+                             tag_names:, parent_post_ids:
     { title:,
-      video_ms:,
       original_created_from: snapshot_time(original_created_from),
       original_created_before: snapshot_time(original_created_before),
-      tag_names: tags.uniq(&:id).map { |tag|
-        "#{ tag.name }#{ sections[tag.id].to_a.map { section_literal(_1) }.join }"
-      }.sort,
+      tag_names: incoming_tag_names_for_snapshot(tag_names),
       parent_post_ids: parent_post_ids.sort }
   end
 
@@ -602,8 +532,10 @@ class PostsController < ApplicationController
     value.to_s
   end
 
-  def section_literal section
-    "[#{ Post.ms_to_time(section[0]) }-#{ section[1] ? Post.ms_to_time(section[1]) : '' }]"
+  def incoming_tag_names_for_snapshot raw_tag_names
+    tags = Tag.normalise_tags!(raw_tag_names, with_tagme: false)
+
+    Tag.expand_parent_tags(tags).map(&:name).uniq.sort
   end
 
   def post_conflict_json post:, base_version_no:, base_snapshot:,
@@ -624,8 +556,6 @@ class PostsController < ApplicationController
   def post_snapshot_changes base_snapshot, current_snapshot, incoming_snapshot
     [scalar_snapshot_change(:title, 'タイトル',
                             base_snapshot, current_snapshot, incoming_snapshot),
-     scalar_snapshot_change(:video_ms, '動画時間',
-                            base_snapshot, current_snapshot, incoming_snapshot),
      scalar_snapshot_change(:original_created_from, 'オリジナルの作成日時（以降）',
                             base_snapshot, current_snapshot, incoming_snapshot),
      scalar_snapshot_change(:original_created_before, 'オリジナルの作成日時（より前）',
@@ -689,32 +619,25 @@ class PostsController < ApplicationController
     PostVersionRecorder.ensure_snapshot!(post, created_by_user: current_user)
 
     post.update!(title: snapshot[:title],
-                 video_ms: snapshot[:video_ms],
                  original_created_from: snapshot[:original_created_from],
                  original_created_before: snapshot[:original_created_before])
 
-    Tag.normalise_tags!(snapshot[:tag_names], with_tagme: false,
-                                               deny_deprecated: true,
-                                               with_sections: true) =>
-        { tags: editable_tags, sections: }
+    editable_tags = Tag.normalise_tags!(snapshot[:tag_names], with_tagme: false)
     TagVersioning.record_tag_snapshots!(editable_tags, created_by_user: current_user)
 
     readonly_tags = post.tags.nico.to_a
 
     tags = readonly_tags + editable_tags
-    tags = Tag.expand_parent_tags(tags).reject(&:deprecated?)
+    tags = Tag.expand_parent_tags(tags)
 
-    post.video_ms = tags.any? { _1.id == Tag.video.id } ? snapshot[:video_ms] : nil
-    validate_video_sections!(post.video_ms, sections)
-    post.save!
-    sync_post_tags!(post, tags, sections)
+    sync_post_tags!(post, tags)
     sync_parent_posts!(post, snapshot[:parent_post_ids])
 
     PostVersionRecorder.record!(post:, event_type: :update, created_by_user: current_user)
   end
 
   def merge_post_snapshots base_snapshot, current_snapshot, incoming_snapshot
-    [:title, :video_ms, :original_created_from, :original_created_before].map {
+    [:title, :original_created_from, :original_created_before].map {
       [_1, merge_scalar_snapshot_value(base_snapshot[_1],
                                        current_snapshot[_1],
                                        incoming_snapshot[_1])]
@@ -758,44 +681,4 @@ class PostsController < ApplicationController
       render_validation_error record
     end
   end
-
-  def normalise_video_ms tags, video_ms_param: params[:video_ms], duration_param: params[:duration]
-    return nil unless tags.any? { _1.id == Tag.video.id }
-
-    if video_ms_param.present?
-      video_ms = Integer(video_ms_param, exception: false)
-      raise VideoMsParseError unless video_ms&.positive?
-
-      return video_ms
-    end
-
-    return nil if duration_param.blank?
-
-    video_ms = Tag.time_to_ms!(duration_param.to_s, tag_name: '動画時間')
-    raise VideoMsParseError unless video_ms.positive?
-
-    video_ms
-  rescue Tag::SectionLiteralParseError
-    raise VideoMsParseError
-  end
-
-  def validate_video_sections! video_ms, sections
-    return unless video_ms
-
-    sections.each_value do |ranges|
-      ranges.each do |begin_ms, end_ms|
-        if begin_ms >= video_ms
-          post = Post.new
-          post.errors.add :video_ms, 'タグ区間の開始が動画時間以上です．'
-          raise ActiveRecord::RecordInvalid, post
-        end
-
-        if end_ms && end_ms > video_ms
-          post = Post.new
-          post.errors.add :video_ms, 'タグ区間の終端が動画時間を超えてゐます．'
-          raise ActiveRecord::RecordInvalid, post
-        end
-      end
-    end
-  end
 end

backend/app/controllers/tag_versions_controller.rb

@@ -17,7 +17,6 @@ class TagVersionsController < ApplicationController
               AND prev.version_no = tag_versions.version_no - 1
         SQL
       .select('tag_versions.*', 'prev.name AS prev_name', 'prev.category AS prev_category',
-              'prev.deprecated_at AS prev_deprecated_at',
               'prev.aliases AS prev_aliases', 'prev.parent_tag_ids AS prev_parent_tag_ids')
     q = q.where('tag_versions.tag_id = ?', tag_id) if tag_id
 
@@ -63,8 +62,6 @@ class TagVersionsController < ApplicationController
         event_type: row.event_type,
         name: { current: row.name, prev: row.attributes['prev_name'] },
         category: { current: row.category, prev: row.attributes['prev_category'] },
-        deprecated_at: { current: row.deprecated_at&.iso8601,
-                         prev: row.attributes['prev_deprecated_at']&.iso8601 },
         aliases: build_version_values(cur_aliases, prev_aliases, key: :name),
         parent_tags:,
         created_at: row.created_at.iso8601,

backend/app/controllers/tags_controller.rb

@@ -1,6 +1,5 @@
 require 'net/http'
 require 'uri'
-require 'set'
 
 
 class TagsController < ApplicationController
@@ -15,8 +14,6 @@ class TagsController < ApplicationController
     post_count_between[1] = nil if post_count_between[1] < 0
     created_between = params[:created_from].presence, params[:created_to].presence
     updated_between = params[:updated_from].presence, params[:updated_to].presence
-    deprecated_given = params.key?(:deprecated)
-    deprecated = bool?(:deprecated)
 
     order = params[:order].to_s.split(':', 2).map(&:strip)
     unless order[0].in?(['name', 'category', 'post_count', 'created_at', 'updated_at'])
@@ -51,9 +48,6 @@ class TagsController < ApplicationController
     q = q.where('tags.created_at <= ?', created_between[1]) if created_between[1]
     q = q.where('tags.updated_at >= ?', updated_between[0]) if updated_between[0]
     q = q.where('tags.updated_at <= ?', updated_between[1]) if updated_between[1]
-    if deprecated_given
-      q = deprecated ? q.where.not(deprecated_at: nil) : q.where(deprecated_at: nil)
-    end
 
     sort_sql =
         case order[0]
@@ -82,20 +76,39 @@ class TagsController < ApplicationController
   def with_depth
     parent_tag_id = params[:parent].to_i
     parent_tag_id = nil if parent_tag_id <= 0
-    material_filter = material_filter_param(default: 'any')
-
-    graph = build_with_depth_graph(material_filter)
 
     tag_ids =
         if parent_tag_id
-          visible_child_tag_ids(parent_tag_id, graph)
+          TagImplication.where(parent_tag_id:).select(:tag_id)
         else
-          visible_root_tag_ids(graph)
+          Tag.where.not(id: TagImplication.select(:tag_id)).select(:id)
         end
 
-    render json: tag_ids
-                 .sort_by { |tag_id| graph[:tags_by_id][tag_id][:name] }
-                 .map { |tag_id| with_depth_lightweight_repr(tag_id, graph) }
+    tags =
+        Tag
+        .joins(:tag_name)
+        .includes(:tag_name, :materials, tag_name: :wiki_page)
+        .where(category: [:meme, :character, :material])
+        .where(id: tag_ids)
+        .order('tag_names.name')
+        .distinct
+        .to_a
+
+    has_children_tag_ids =
+        if tags.empty?
+          []
+        else
+          TagImplication
+              .joins(:tag)
+              .where(parent_tag_id: tags.map(&:id),
+                     tags: { category: [:meme, :character, :material] })
+              .distinct
+              .pluck(:parent_tag_id)
+        end
+
+    render json: tags.map { |tag|
+      TagRepr.base(tag).merge(has_children: has_children_tag_ids.include?(tag.id), children: [])
+    }
   end
 
   def autocomplete
@@ -120,7 +133,6 @@ class TagsController < ApplicationController
 
     base = Tag.joins(:tag_name)
               .includes(:tag_name, :materials, tag_name: :wiki_page)
-              .where(deprecated_at: nil)
     base = base.where('tags.post_count > 0') if present_only
 
     canonical_hit =
@@ -220,16 +232,13 @@ class TagsController < ApplicationController
   def materials_by_name
     name = params[:name].to_s.strip
     return render_bad_request('name は必須です．') if name.blank?
-    material_filter = material_filter_param(default: 'any')
 
     tag = Tag.joins(:tag_name)
              .includes(:tag_name, :materials, tag_name: :wiki_page)
              .find_by(tag_names: { name: })
     return head :not_found unless tag
 
-    graph = build_with_depth_graph(material_filter)
-
-    render json: build_tag_children(tag, graph:)
+    render json: build_tag_children(tag)
   end
 
   def update_all
@@ -243,22 +252,19 @@ class TagsController < ApplicationController
     category = params[:category].to_s.strip
     return render_unprocessable_entity('名前は必須です．', field: :name) if name.blank?
     return render_unprocessable_entity('カテゴリは必須です．', field: :category) if category.blank?
-    return render_unprocessable_entity '廃止状態は必須です．', field: :deprecated unless params.key?(:deprecated)
 
-    return unless validate_tag_rename(tag, name)
-
-    alias_names = params[:aliases].to_s.split.uniq
-    parent_names = params[:parent_tags].to_s.split.uniq
-    deprecated = bool?(:deprecated)
-
-    if tag.nico? && deprecated
-      return render_unprocessable_entity 'ニコタグは廃止できません．', field: :deprecated
+    if name != tag.name &&
+        tag.in?([Tag.tagme, Tag.bot, Tag.no_deerjikist, Tag.video, Tag.niconico])
+      return render_unprocessable_entity('システム・タグの名称は変更できません．', field: :name)
     end
 
     if tag.nico? || category == 'nico'
-      return render_unprocessable_entity 'ニコタグは変更できません．', field: :category
+      return render_unprocessable_entity('ニコタグは変更できません．', field: :category)
     end
 
+    alias_names = params[:aliases].to_s.split.uniq
+    parent_names = params[:parent_tags].to_s.split.uniq
+
     ApplicationRecord.transaction do
       TagVersioning.ensure_snapshot!(tag, created_by_user: current_user)
 
@@ -266,12 +272,8 @@ class TagsController < ApplicationController
       name_changed = name != old_name
       wiki_page = tag.tag_name.wiki_page if name_changed
 
-      if tag.deprecated? == deprecated
-        tag.update!(category:)
-      else
-        tag.update!(category:, deprecated_at: deprecated ? Time.current : nil)
-      end
-      rename_tag_name!(tag, name) if name_changed
+      tag.update!(category:)
+      tag.tag_name.update!(name:)
 
       alias_names << old_name if name_changed
       alias_names.delete(name)
@@ -298,19 +300,11 @@ class TagsController < ApplicationController
 
     name = params[:name].presence
     category = params[:category].presence
-    deprecated_given = params.key?(:deprecated)
-    deprecated = bool?(:deprecated)
 
     tag = Tag.find(params[:id])
 
-    if tag.nico? && deprecated_given && deprecated
-      return render_unprocessable_entity 'ニコタグは廃止できません．', field: :deprecated
-    end
-
-    return unless validate_tag_rename(tag, name)
-
     if tag.nico? || (category.present? && category == 'nico')
-      return render_unprocessable_entity 'ニコタグは変更できません．', field: :category
+      return render_unprocessable_entity('ニコタグは変更できません．', field: :category)
     end
 
     ApplicationRecord.transaction do
@@ -320,11 +314,8 @@ class TagsController < ApplicationController
       name_changed = name.present? && name != old_name
       wiki_page = tag.tag_name.wiki_page if name_changed
 
-      rename_tag_name!(tag, name) if name_changed
+      tag.tag_name.update!(name:) if name.present?
       tag.update!(category:) if category.present?
-      if deprecated_given && tag.deprecated? != deprecated
-        tag.update!(deprecated_at: deprecated ? Time.current : nil)
-      end
 
       tag.reload
 
@@ -341,178 +332,18 @@ class TagsController < ApplicationController
 
   private
 
-  def material_filter_param default:
-    value = params[:material_filter].to_s.presence
-    return default unless ['present', 'missing', 'any'].include?(value)
-
-    value
-  end
-
-  def build_with_depth_graph material_filter
-    children_by_parent_id = Hash.new { |h, k| h[k] = [] }
-    parent_ids_by_child_id = Hash.new { |h, k| h[k] = [] }
-
-    TagImplication.pluck(:parent_tag_id, :tag_id).each do |parent_id, child_id|
-      children_by_parent_id[parent_id] << child_id
-      parent_ids_by_child_id[child_id] << parent_id
-    end
-
-    tag_ids = (children_by_parent_id.keys +
-               parent_ids_by_child_id.keys +
-               Tag.where(category: ['meme', 'character', 'material']).pluck(:id)).uniq
-
-    material_tag_ids = Material.unscoped.kept.where.not(tag_id: nil).distinct.pluck(:tag_id).to_set
-
-    tags_by_id = Tag.joins(:tag_name)
-                    .where(id: tag_ids)
-                    .pluck('tags.id', 'tag_names.name', 'tags.category', 'tags.deprecated_at')
-                    .each_with_object({ }) do |(id, name, category, deprecated_at), h|
-      h[id] = { name:, category:, deprecated: deprecated_at.present?,
-                has_material: material_tag_ids.include?(id) }
-    end
-
-    { children_by_parent_id:, parent_ids_by_child_id:, tags_by_id:,
-      visible_child_tag_ids_by_parent_id: { },
-      visible_subtree_by_tag_id: { },
-      material_filter: }
-  end
-
-  def visible_root_tag_ids graph
-    root_ids = Set.new
-
-    graph[:tags_by_id].each do |tag_id, attrs|
-      next unless visible_root_tag?(tag_id, graph)
-      next unless visible_subtree?(tag_id, graph)
-
-      if attrs[:deprecated]
-        collect_visible_child_tag_ids(tag_id, graph, root_ids, Set.new)
-      else
-        root_ids << tag_id
-      end
-    end
-
-    root_ids.to_a
-  end
-
-  def visible_root_tag? tag_id, graph
-    seen = Set.new([tag_id])
-    stack = graph[:parent_ids_by_child_id][tag_id].dup
-
-    until stack.empty?
-      parent_id = stack.pop
-      next if seen.include?(parent_id)
-
-      seen << parent_id
-
-      parent = graph[:tags_by_id][parent_id]
-      next unless parent
-
-      return false unless parent[:deprecated]
-
-      stack.concat(graph[:parent_ids_by_child_id][parent_id])
-    end
-
-    true
-  end
-
-  def visible_child_tag_ids parent_tag_id, graph
-    cache = graph[:visible_child_tag_ids_by_parent_id]
-    return cache[parent_tag_id] if cache.key?(parent_tag_id)
-
-    visible_ids = Set.new
-
-    graph[:children_by_parent_id][parent_tag_id].each do |child_tag_id|
-      collect_visible_child_tag_ids(child_tag_id, graph, visible_ids, Set.new([parent_tag_id]))
-    end
-
-    cache[parent_tag_id] = visible_ids.to_a
-  end
-
-  def collect_visible_child_tag_ids tag_id, graph, visible_ids, seen
-    return if seen.include?(tag_id)
-
-    seen = seen.dup << tag_id
-    tag = graph[:tags_by_id][tag_id]
-    return unless tag
-
-    if tag[:deprecated]
-      graph[:children_by_parent_id][tag_id].each do |child_tag_id|
-        collect_visible_child_tag_ids(child_tag_id, graph, visible_ids, seen)
-      end
-      return
-    end
-
-    if with_depth_visible_tag?(tag, graph[:material_filter])
-      visible_ids << tag_id
-      return
-    end
-
-    visible_ids << tag_id if graph[:children_by_parent_id][tag_id].any? { |child_tag_id|
-      visible_subtree?(child_tag_id, graph)
-    }
-  end
-
-  def with_depth_visible_tag? tag, material_filter
-    return false unless tag[:category].in?(['meme', 'character', 'material']) && !tag[:deprecated]
-
-    case material_filter
-    when 'present'
-      tag[:has_material]
-    when 'missing'
-      !tag[:has_material]
-    else
-      true
-    end
-  end
-
-  def visible_subtree? tag_id, graph
-    cache = graph[:visible_subtree_by_tag_id]
-    return cache[tag_id] if cache.key?(tag_id)
-
-    tag = graph[:tags_by_id][tag_id]
-    return cache[tag_id] = false unless tag
-
-    if tag[:deprecated]
-      return cache[tag_id] =
-                 graph[:children_by_parent_id][tag_id].any? { |child_tag_id|
-                   visible_subtree?(child_tag_id, graph)
-                 }
-    end
-
-    cache[tag_id] =
-        with_depth_visible_tag?(tag, graph[:material_filter]) ||
-        graph[:children_by_parent_id][tag_id].any? { |child_tag_id|
-          visible_subtree?(child_tag_id, graph)
-        }
-  end
-
-  def with_depth_lightweight_repr tag_id, graph
-    tag = graph[:tags_by_id][tag_id]
-
-    { id: tag_id,
-      name: tag[:name],
-      category: tag[:category],
-      deprecated: tag[:deprecated],
-      has_material: tag[:has_material],
-      has_children: visible_child_tag_ids(tag_id, graph).present?,
-      children: [] }
-  end
-
-  def build_tag_children tag, graph: nil
+  def build_tag_children tag
     material = tag.materials.first
-    tag_graph = graph && graph[:tags_by_id][tag.id]
-    material =
-        nil if tag_graph && !with_depth_visible_tag?(tag_graph, graph[:material_filter])
-
-    children = tag.children.sort_by(&:name)
-    if graph
-      children = children.filter { |child_tag| visible_subtree?(child_tag.id, graph) }
+    file = nil
+    content_type = nil
+    if material&.file&.attached?
+      file = rails_storage_proxy_url(material.file, only_path: false)
+      content_type = material.file.blob.content_type
     end
 
     TagRepr.base(tag).merge(
-        children: children.map { build_tag_children(_1, graph:) },
-        has_material: tag_graph ? tag_graph[:has_material] : material.present?,
-        material: material && MaterialRepr.base(material, host: request.base_url))
+        children: tag.children.sort_by { _1.name }.map { build_tag_children(_1) },
+        material: material.as_json&.merge(file:, content_type:))
   end
 
   def record_tag_version! tag, event_type:, created_by_user:, name_changed: false, wiki_page: nil
@@ -534,67 +365,6 @@ class TagsController < ApplicationController
         created_by_user:)
   end
 
-  def validate_tag_rename tag, name
-    return true if name.blank? || name == tag.name
-
-    if tag.in?([Tag.tagme, Tag.bot, Tag.no_deerjikist, Tag.video, Tag.niconico])
-      render_unprocessable_entity 'システム・タグの名称は変更できません．', field: :name
-      return false
-    end
-
-    target_tag_name = TagName.with_discarded.find_by(name:)
-    return true if target_tag_name.nil?
-    return true if target_tag_name.canonical_id?
-
-    render_unprocessable_entity 'その名前は既に使はれてゐます．', field: :name
-    false
-  end
-
-  def rename_tag_name! tag, name
-    return if name == tag.name
-
-    current_tag_name = tag.tag_name
-    target_tag_name = TagName.with_discarded.find_by(name:)
-
-    if target_tag_name.nil?
-      current_tag_name.update!(name:)
-      return
-    end
-
-    promote_tag_alias!(
-        tag,
-        current_tag_name:,
-        promoted_tag_name: target_tag_name)
-  end
-
-  def promote_tag_alias! tag, current_tag_name:, promoted_tag_name:
-    old_owner_tag = promoted_tag_name.canonical&.tag
-
-    if old_owner_tag && old_owner_tag != tag
-      TagVersioning.ensure_snapshot!(old_owner_tag, created_by_user: current_user)
-    end
-
-    promoted_tag_name.undiscard! if promoted_tag_name.discarded?
-    promoted_tag_name.update!(canonical: nil)
-
-    TagName.with_discarded
-           .where(canonical_id: current_tag_name.id)
-           .where.not(id: promoted_tag_name.id)
-           .find_each do |alias_tag_name|
-      alias_tag_name.update!(canonical: promoted_tag_name)
-    end
-
-    current_tag_name.wiki_page&.update!(tag_name: promoted_tag_name)
-    tag.update!(tag_name: promoted_tag_name)
-    current_tag_name.association(:wiki_page).reset
-    current_tag_name.association(:tag).reset
-    current_tag_name.reload.update!(canonical: promoted_tag_name)
-
-    return unless old_owner_tag && old_owner_tag != tag
-
-    record_tag_version!(old_owner_tag.reload, event_type: :update, created_by_user: current_user)
-  end
-
   def update_aliases! tag, alias_names
     alias_names = alias_names.uniq
 

backend/app/controllers/user_settings_controller.rb

@@ -1,61 +0,0 @@
-class UserSettingsController < ApplicationController
-  wrap_parameters false
-
-  def show
-    return head :unauthorized unless current_user
-
-    render json: current_setting.serializable_hash
-  end
-
-  def update
-    return head :unauthorized unless current_user
-
-    raw_attributes = editable_raw_attributes
-    field_errors = validate_raw_attributes(raw_attributes)
-    return render_validation_error fields: field_errors if field_errors.present?
-
-    setting = current_setting
-    setting.assign_attributes(raw_attributes)
-
-    if setting.save
-      render json: setting.serializable_hash, status: :ok
-    else
-      render_validation_error setting
-    end
-  end
-
-  private
-
-  def current_setting
-    Setting.find_or_create_by!(user: current_user) do |setting|
-      setting.assign_attributes(Setting.defaults)
-    end
-  rescue ActiveRecord::RecordNotUnique
-    Setting.find_by!(user: current_user)
-  end
-
-  def editable_raw_attributes
-    request.request_parameters.slice(*Setting::EDITABLE_ATTRIBUTES)
-  end
-
-  def validate_raw_attributes raw_attributes
-    raw_attributes.each_with_object({ }) do |(key, value), errors|
-      next if value_matches_type?(key, value)
-
-      errors[key.to_sym] = ['値の型が不正です．']
-    end
-  end
-
-  def value_matches_type? key, value
-    case Setting::TYPE_BY_ATTRIBUTE.fetch(key)
-    when :string
-      value.is_a?(String)
-    when :integer
-      value.is_a?(Integer)
-    when :boolean
-      value == true || value == false
-    else
-      false
-    end
-  end
-end

backend/app/controllers/user_theme_slots_controller.rb

@@ -1,38 +0,0 @@
-class UserThemeSlotsController < ApplicationController
-  wrap_parameters false
-
-  def index
-    return head :unauthorized unless current_user
-
-    render json: current_user
-                 .theme_slots
-                 .order(:base_theme, :slot_no)
-                 .map { |slot| slot.serializable_hash }
-  end
-
-  def update
-    return head :unauthorized unless current_user
-
-    base_theme = params[:base_theme].to_s
-    slot_no = params[:slot_no].to_i
-    tokens = params[:tokens]
-
-    unless UserThemeSlot::BASE_THEMES.include?(base_theme)
-      return render_validation_error fields: { base_theme: ['値が不正です．'] }
-    end
-    unless UserThemeSlot::SLOT_NOS.include?(slot_no)
-      return render_validation_error fields: { slot_no: ['値が不正です．'] }
-    end
-    unless tokens.is_a?(ActionController::Parameters) || tokens.is_a?(Hash)
-      return render_validation_error fields: { tokens: ['JSON object で指定してください．'] }
-    end
-
-    slot = UserThemeSlot.find_or_initialize_by(user: current_user,
-                                               base_theme:,
-                                               slot_no:)
-    slot.tokens = tokens.is_a?(ActionController::Parameters) ? tokens.to_unsafe_h : tokens
-    slot.save!
-
-    render json: slot.serializable_hash, status: :ok
-  end
-end

backend/app/controllers/wiki_pages_controller.rb

@@ -4,18 +4,17 @@ class WikiPagesController < ApplicationController
   def index
     title = params[:title].to_s.strip
     if title.blank?
-      return render json: WikiPageRepr.base(
-          WikiPage.joins(:tag_name).includes(tag_name: :tag))
+      return render json: WikiPageRepr.base(WikiPage.joins(:tag_name).includes(:tag_name))
     end
 
-    q = WikiPage.joins(:tag_name).includes(tag_name: :tag)
+    q = WikiPage.joins(:tag_name).includes(:tag_name)
         .where('tag_names.name LIKE ?', "%#{ WikiPage.sanitize_sql_like(title) }%")
     render json: WikiPageRepr.base(q.limit(20))
   end
 
   def show
     page = WikiPage.joins(:tag_name)
-                   .includes(tag_name: :tag)
+                   .includes(:tag_name)
                    .find_by(id: params[:id])
     render_wiki_page_or_404 page
   end
@@ -23,7 +22,7 @@ class WikiPagesController < ApplicationController
   def show_by_title
     title = params[:title].to_s.strip
     page = WikiPage.joins(:tag_name)
-                   .includes(tag_name: :tag)
+                   .includes(:tag_name)
                    .find_by(tag_name: { name: title })
     render_wiki_page_or_404 page
   end
@@ -52,7 +51,7 @@ class WikiPagesController < ApplicationController
     from = params[:from].presence
     to = params[:to].presence
 
-    page = WikiPage.joins(:tag_name).includes(tag_name: :tag).find(id)
+    page = WikiPage.joins(:tag_name).includes(:tag_name).find(id)
 
     from_rev = from && page.wiki_revisions.find(from)
     to_rev = to ? page.wiki_revisions.find(to) : page.current_revision
@@ -77,7 +76,6 @@ class WikiPagesController < ApplicationController
 
     render json: { wiki_page_id:      page.id,
                    title:             page.title,
-                   deprecated_at:     page.deprecated_at,
                    older_revision_id: from_rev&.id,
                    newer_revision_id: to_rev.id,
                    diff:              diff_json }
@@ -159,7 +157,7 @@ class WikiPagesController < ApplicationController
   def changes
     id = params[:id].presence
     q = WikiRevision.joins(wiki_page: :tag_name)
-                    .includes(:created_user, wiki_page: { tag_name: :tag })
+                    .includes(:created_user, wiki_page: :tag_name)
                     .order(id: :desc)
     q = q.where(wiki_page_id: id) if id
 
@@ -167,9 +165,7 @@ class WikiPagesController < ApplicationController
       { revision_id:  rev.id,
         pred:         rev.base_revision_id,
         succ:         nil,
-        wiki_page:    { id: rev.wiki_page_id,
-                        title: rev.wiki_page.title,
-                        deprecated_at: rev.wiki_page.deprecated_at },
+        wiki_page:    { id: rev.wiki_page_id, title: rev.wiki_page.title },
         user:         rev.created_user && { id: rev.created_user.id, name: rev.created_user.name },
         kind:         rev.kind,
         message:      rev.message,

backend/app/models/gekanator_ai_run.rb

@@ -1,21 +0,0 @@
-class GekanatorAiRun < ApplicationRecord
-  STATUSES = ['pending', 'running', 'succeeded', 'failed', 'blocked_budget'].freeze
-
-  belongs_to :gekanator_question_suggestion
-
-  validates :model, presence: true, length: { maximum: 255 }
-  validates :status, presence: true, inclusion: { in: STATUSES }
-  validates :input_tokens,
-            presence: true,
-            numericality: { only_integer: true, greater_than_or_equal_to: 0 }
-  validates :output_tokens,
-            presence: true,
-            numericality: { only_integer: true, greater_than_or_equal_to: 0 }
-  validates :estimated_cost_jpy,
-            presence: true,
-            numericality: { greater_than_or_equal_to: 0 }
-
-  scope :this_month, lambda {
-    where(created_at: Time.current.beginning_of_month..Time.current.end_of_month)
-  }
-end

backend/app/models/gekanator_game.rb

@@ -1,15 +0,0 @@
-class GekanatorGame < ApplicationRecord
-  belongs_to :user
-  belongs_to :guessed_post, class_name: 'Post'
-  belongs_to :correct_post, class_name: 'Post'
-  has_many :question_suggestions,
-           class_name: 'GekanatorQuestionSuggestion',
-           dependent: :delete_all
-  has_many :question_examples,
-           class_name: 'GekanatorQuestionExample',
-           dependent: :delete_all
-
-  validates :answers, presence: true
-  validates :question_count, numericality: { greater_than_or_equal_to: 0 }
-  validates :won, inclusion: { in: [true, false] }
-end

backend/app/models/gekanator_question.rb

@@ -1,23 +0,0 @@
-class GekanatorQuestion < ApplicationRecord
-  KINDS = ['tag', 'source', 'title', 'original_date', 'post_similarity'].freeze
-  SOURCES = ['user_suggested', 'ai_generated', 'admin_curated'].freeze
-  STATUSES = ['pending', 'accepted', 'rejected', 'disabled'].freeze
-
-  belongs_to :gekanator_question_suggestion, optional: true
-  belongs_to :created_by, class_name: 'User', optional: true
-  has_many :gekanator_question_examples, dependent: :delete_all
-
-  validates :kind, presence: true, inclusion: { in: KINDS }
-  validates :source, presence: true, inclusion: { in: SOURCES }
-  validates :status, presence: true, inclusion: { in: STATUSES }
-  validates :text, presence: true, length: { maximum: 1000 }
-  validates :condition, presence: true
-  validates :priority_weight,
-            presence: true,
-            numericality: {
-              greater_than: 0,
-              less_than_or_equal_to: 3
-            }
-
-  scope :accepted, -> { where(status: 'accepted') }
-end

backend/app/models/gekanator_question_example.rb

@@ -1,97 +0,0 @@
-class GekanatorQuestionExample < ApplicationRecord
-  ANSWERS = GekanatorQuestionSuggestion::ANSWERS
-  NON_UNKNOWN_ANSWERS = ANSWERS - ['unknown']
-  SOURCES = ['initial_suggestion', 'post_game_answer', 'post_game_extra'].freeze
-
-  belongs_to :gekanator_question
-  belongs_to :post
-  belongs_to :user
-  belongs_to :gekanator_game, optional: true
-
-  validates :answer, presence: true, inclusion: { in: ANSWERS }
-  validates :answer_counts, presence: true
-  validates :sample_count,
-            presence: true,
-            numericality: {
-              only_integer: true,
-              greater_than: 0
-            }
-  validates :source, presence: true, inclusion: { in: SOURCES }
-  validates :weight,
-            presence: true,
-            numericality: {
-              greater_than: 0
-            }
-
-  before_validation :normalize_learning_state
-
-  def record_answer!(answer:, source:, gekanator_game: nil)
-    answer = answer.to_s
-    raise ArgumentError, 'invalid answer' unless ANSWERS.include?(answer)
-
-    counts = normalized_answer_counts
-    counts[answer] += 1
-
-    self.answer_counts = counts
-    self.sample_count = counts.values.sum
-    self.gekanator_game = gekanator_game if gekanator_game.present?
-    self.source = source
-
-    apply_aggregated_answer!(preferred_answer: answer)
-    self
-  end
-
-  private
-
-  def normalize_learning_state
-    counts = normalized_answer_counts
-
-    if counts.values.sum.zero? && answer.present?
-      counts[answer] = 1
-    end
-
-    self.answer_counts = counts
-    self.sample_count = counts.values.sum
-
-    apply_aggregated_answer!
-  end
-
-  def apply_aggregated_answer!(preferred_answer: nil)
-    counts = normalized_answer_counts
-    known_counts = counts.slice(*NON_UNKNOWN_ANSWERS)
-    known_total = known_counts.values.sum
-
-    if known_total.zero?
-      self.answer = 'unknown'
-      self.weight = 0.1
-      return
-    else
-      max_count = known_counts.values.max
-      candidates = known_counts.select { |_answer, count| count == max_count }.keys
-      self.answer =
-          if preferred_answer.present? && candidates.include?(preferred_answer)
-            preferred_answer
-          elsif answer.present? && candidates.include?(answer)
-            answer
-          else
-            candidates.first
-          end
-    end
-
-    consensus = max_count.to_f / known_total
-    self.weight = Math.sqrt(known_total) * consensus
-  end
-
-  def normalized_answer_counts
-    base = ANSWERS.index_with(0)
-
-    answer_counts.to_h.each do |key, value|
-      answer_key = key.to_s
-      next unless ANSWERS.include?(answer_key)
-
-      base[answer_key] = value.to_i
-    end
-
-    base
-  end
-end

backend/app/models/gekanator_question_suggestion.rb

@@ -1,12 +0,0 @@
-class GekanatorQuestionSuggestion < ApplicationRecord
-  ANSWERS = ['yes', 'no', 'partial', 'probably_no', 'unknown'].freeze
-
-  belongs_to :gekanator_game
-  belongs_to :user
-  has_many :gekanator_questions, dependent: :nullify
-  has_many :gekanator_ai_runs, dependent: :destroy
-
-  validates :question_text, presence: true, length: { maximum: 1000 }
-  validates :answer, presence: true, inclusion: { in: ANSWERS }
-  validates :processed, inclusion: { in: [true, false] }
-end

backend/app/models/material.rb

@@ -1,9 +1,6 @@
 class Material < ApplicationRecord
   include MyDiscard
 
-  SOURCE_KINDS = ['uri', 'google_drive_path', 'google_drive_file',
-                  'legacy_drive_path'].freeze
-
   default_scope -> { kept }
 
   belongs_to :parent, class_name: 'Material', optional: true
@@ -13,18 +10,9 @@ class Material < ApplicationRecord
   belongs_to :created_by_user, class_name: 'User', optional: true
   belongs_to :updated_by_user, class_name: 'User', optional: true
 
-  has_many :material_versions, dependent: :destroy
-  has_many :material_export_items, dependent: :destroy
-
   has_one_attached :file, dependent: :purge
-  has_one_attached :thumbnail, dependent: :purge
 
-  before_validation :assign_normalized_source_key
-
-  validates :tag_id, uniqueness: true, allow_nil: true
-  validates :source_kind,
-            inclusion: { in: SOURCE_KINDS },
-            allow_blank: true
+  validates :tag_id, presence: true, uniqueness: true
 
   validate :file_must_be_attached
   validate :tag_must_be_material_category
@@ -35,37 +23,8 @@ class Material < ApplicationRecord
     file.blob.content_type
   end
 
-  def file_byte_size
-    return nil unless file&.attached?
-
-    file.blob.byte_size
-  end
-
-  def file_filename
-    return nil unless file&.attached?
-
-    file.blob.filename.to_s
-  end
-
-  def snapshot_export_paths
-    material_export_items.order(:profile).pluck(:profile, :export_path).to_h
-  end
-
   private
 
-  def assign_normalized_source_key
-    if source_kind.blank?
-      self.normalized_source_key = nil
-      return
-    end
-
-    self.normalized_source_key =
-        MaterialSyncSuppression.normalize_source_key(source_kind:,
-                                                     source_uri:,
-                                                     drive_path: source_path,
-                                                     drive_file_id: source_file_id)
-  end
-
   def file_must_be_attached
     return if url.present? || file.attached?
 

backend/app/models/material_export_item.rb

@@ -1,48 +0,0 @@
-class MaterialExportItem < ApplicationRecord
-  VALID_PROFILES = ['legacy_drive'].freeze
-
-  belongs_to :material
-  belongs_to :created_by_user, class_name: 'User', optional: true
-
-  validates :profile, presence: true, inclusion: { in: VALID_PROFILES }
-  validates :export_path, presence: true, uniqueness: { scope: :profile }
-  validates :material_id, uniqueness: { scope: :profile }
-  validate :export_path_must_be_relative_safe_path
-
-  scope :enabled, -> { where(enabled: true) }
-
-  private
-
-  def export_path_must_be_relative_safe_path
-    return if export_path.blank?
-
-    if export_path.start_with?('/')
-      errors.add(:export_path, '絶対パスは使へません．')
-    end
-
-    if export_path.match?(/\A[A-Za-z]:\//)
-      errors.add(:export_path, '絶対パスは使へません．')
-    end
-
-    if export_path.include?('\\')
-      errors.add(:export_path, '/ 区切りで指定してください．')
-    end
-
-    if export_path.include?("\0")
-      errors.add(:export_path, 'NUL は使へません．')
-    end
-
-    parts = export_path.split('/')
-    if export_path.include?('//')
-      errors.add(:export_path, '空の path segment は使へません．')
-    end
-
-    if parts.any? { |part| part.in?(['.', '..']) }
-      errors.add(:export_path, '.. は使へません．')
-    end
-
-    if export_path.end_with?('/')
-      errors.add(:export_path, 'directory path は使へません．')
-    end
-  end
-end

backend/app/models/material_import_block.rb

@@ -1,29 +0,0 @@
-class MaterialImportBlock < ApplicationRecord
-  MATCH_KINDS = ['sha256', 'exact_path', 'path_prefix', 'manual'].freeze
-  REASONS = [
-    'copyright_high_risk',
-    'copyright_takedown',
-    'adult_or_sensitive',
-    'personal_information',
-    'malware_or_dangerous_file',
-    'duplicate_or_low_quality',
-    'source_owner_request',
-    'other'
-  ].freeze
-
-  belongs_to :created_by_user, class_name: 'User', optional: true
-
-  validates :match_kind, presence: true, inclusion: { in: MATCH_KINDS }
-  validates :reason, presence: true, inclusion: { in: REASONS }
-  validates :sha256, length: { is: 64 }, allow_blank: true
-  validate :match_value_must_be_present
-
-  private
-
-  def match_value_must_be_present
-    return if match_kind == 'manual'
-    return if sha256.present? || external_path_pattern.present?
-
-    errors.add(:base, 'sha256 または external_path_pattern は必須です．')
-  end
-end

backend/app/models/material_sync_source.rb

@@ -1,45 +0,0 @@
-class MaterialSyncSource < ApplicationRecord
-  SOURCE_KINDS = ['uri', 'google_drive_path', 'google_drive_file', 'legacy_drive_path'].freeze
-
-  belongs_to :created_by_user, class_name: 'User', optional: true
-  belongs_to :updated_by_user, class_name: 'User', optional: true
-
-  validates :name, presence: true
-  validates :source_kind,
-            presence: true,
-            inclusion: { in: SOURCE_KINDS }
-  validates :profile, presence: true, inclusion: { in: MaterialExportItem::VALID_PROFILES }
-  validate :source_value_must_be_present
-
-  scope :enabled, -> { where(enabled: true) }
-
-  def normalized_source_key
-    MaterialSyncSuppression.normalize_source_key(source_kind:,
-                                                 source_uri:,
-                                                 source_path:,
-                                                 source_file_id:)
-  end
-
-  private
-
-  def source_value_must_be_present
-    return if source_value_present?
-
-    errors.add(:base, '同期元を指定してください．')
-  end
-
-  def source_value_present?
-    case source_kind
-    when 'uri'
-      source_uri.present?
-    when 'google_drive_file'
-      source_file_id.present? || source_uri.present?
-    when 'google_drive_path'
-      source_file_id.present? || source_uri.present?
-    when 'legacy_drive_path'
-      source_path.present?
-    else
-      normalized_source_key.present?
-    end
-  end
-end

backend/app/models/material_sync_suppression.rb

@@ -1,105 +0,0 @@
-class MaterialSyncSuppression < ApplicationRecord
-  SOURCE_KINDS = [
-    'uri',
-    'google_drive_path',
-    'google_drive_path_prefix',
-    'google_drive_file',
-    'legacy_drive_path',
-    'legacy_drive_path_prefix'
-  ].freeze
-
-  REASONS = [
-    'copyright_high_risk',
-    'copyright_takedown',
-    'adult_or_sensitive',
-    'personal_information',
-    'malware_or_dangerous_file',
-    'duplicate_or_low_quality',
-    'source_owner_request',
-    'other'
-  ].freeze
-
-  belongs_to :created_by_user, class_name: 'User', optional: true
-
-  before_validation :assign_normalized_source_key
-
-  validates :source_kind, presence: true, inclusion: { in: SOURCE_KINDS }
-  validates :reason, presence: true, inclusion: { in: REASONS }
-  validates :normalized_source_key, presence: true, uniqueness: true
-  validate :source_value_must_be_present
-  validate :drive_path_must_be_safe_relative_path
-
-  def self.normalize_source_key source_kind:,
-                                source_uri: nil,
-                                drive_path: nil,
-                                drive_file_id: nil,
-                                source_path: nil,
-                                source_file_id: nil
-    kind = source_kind.to_s
-    value =
-        case kind
-        when 'uri'
-          source_uri.to_s.strip
-        when 'google_drive_path', 'google_drive_path_prefix',
-             'legacy_drive_path', 'legacy_drive_path_prefix'
-          (source_path || drive_path).to_s.strip.gsub(%r{/+}, '/')
-        when 'google_drive_file'
-          (source_file_id || drive_file_id).to_s.strip
-        else
-          ''
-        end
-
-    return nil if kind.blank? || value.blank?
-
-    "#{ kind }:#{ value }"
-  end
-
-  private
-
-  def assign_normalized_source_key
-    normalize_path_fields!
-    self.normalized_source_key =
-        self.class.normalize_source_key(source_kind:,
-                                        source_uri:,
-                                        drive_path:,
-                                        drive_file_id:)
-  end
-
-  def source_value_must_be_present
-    return if normalized_source_key.present?
-
-    errors.add(:base, '同期元を指定してください．')
-  end
-
-  def drive_path_must_be_safe_relative_path
-    return unless source_kind.in?(
-        ['google_drive_path', 'google_drive_path_prefix',
-         'legacy_drive_path', 'legacy_drive_path_prefix'])
-
-    value = drive_path.to_s
-    return if value.blank?
-
-    if value.start_with?('/') || value.match?(/\A[A-Za-z]:\//)
-      errors.add(:drive_path, '相対 path を指定してください．')
-    end
-    if value.start_with?('My Drive/', 'マイドライブ/')
-      errors.add(:drive_path, '同期元フォルダからの相対 path を指定してください．')
-    end
-    errors.add(:drive_path, 'NUL は使へません．') if value.include?("\0")
-    errors.add(:drive_path, '連続スラッシュは使へません．') if value.include?('//')
-    errors.add(:drive_path, '末尾スラッシュは使へません．') if value.end_with?('/')
-
-    parts = value.split('/')
-    if parts.any? { |part| part.in?(['.', '..']) }
-      errors.add(:drive_path, '. や .. は使へません．')
-    end
-  end
-
-  def normalize_path_fields!
-    return unless source_kind.in?(
-        ['google_drive_path', 'google_drive_path_prefix',
-         'legacy_drive_path', 'legacy_drive_path_prefix'])
-
-    self.drive_path = drive_path.to_s.tr('\\', '/').strip.presence
-  end
-end

backend/app/models/material_version.rb

@@ -1,17 +0,0 @@
-class MaterialVersion < ApplicationRecord
-  EVENT_TYPE_MAP = { create: 'create',
-                     update: 'update',
-                     discard: 'discard',
-                     restore: 'restore' }.freeze
-
-  include VersionRecord
-
-  belongs_to :material
-  belongs_to :tag, optional: true
-  belongs_to :parent, class_name: 'Material', optional: true
-  belongs_to :updated_by_user, class_name: 'User', optional: true
-
-  def export_paths_hash
-    export_paths_json || {}
-  end
-end

backend/app/models/post.rb

@@ -1,19 +1,5 @@
 class Post < ApplicationRecord
   require 'mini_magick'
-  require 'stringio'
-
-  def self.resized_thumbnail_attachment(upload)
-    upload.rewind
-    image = MiniMagick::Image.read(upload.read)
-    image.resize '180x180'
-    image.format 'jpg'
-
-    { io: StringIO.new(image.to_blob),
-      filename: 'resized_thumbnail.jpg',
-      content_type: 'image/jpeg' }
-  ensure
-    upload.rewind
-  end
 
   belongs_to :uploaded_user, class_name: 'User', optional: true
 
@@ -21,23 +7,10 @@ class Post < ApplicationRecord
   has_many :active_post_tags, -> { kept }, class_name: 'PostTag', inverse_of: :post
   has_many :post_tags_with_discarded, -> { with_discarded }, class_name: 'PostTag'
   has_many :tags, through: :active_post_tags
-  has_many :active_tags, -> { where(tags: { deprecated_at: nil }) },
-           through: :active_post_tags, source: :tag
 
   has_many :user_post_views, dependent: :delete_all
   has_many :post_similarities, dependent: :delete_all
   has_many :post_versions
-  has_many :gekanator_guessed_games,
-           class_name: 'GekanatorGame',
-           foreign_key: :guessed_post_id,
-           dependent: :delete_all,
-           inverse_of: :guessed_post
-  has_many :gekanator_correct_games,
-           class_name: 'GekanatorGame',
-           foreign_key: :correct_post_id,
-           dependent: :delete_all,
-           inverse_of: :correct_post
-  has_many :gekanator_question_examples, dependent: :delete_all
 
   has_many :parent_post_implications,
            class_name: 'PostImplication',
@@ -60,7 +33,6 @@ class Post < ApplicationRecord
   before_validation :normalise_url
 
   validates :url, presence: true, uniqueness: true
-  validates :video_ms, numericality: { only_integer: true, greater_than: 0 }, allow_nil: true
 
   validate :validate_original_created_range
   validate :url_must_be_http_url
@@ -84,42 +56,7 @@ class Post < ApplicationRecord
     super(options).merge(thumbnail: nil)
   end
 
-  def snapshot_tag_names
-    post_tags
-        .kept
-        .joins(tag: :tag_name)
-        .includes(:sections, tag: :tag_name)
-        .order('tag_names.name')
-        .map do |post_tag|
-      name = post_tag.tag.tag_name.name
-      sections = post_tag.sections.sort_by(&:begin_ms)
-
-      next name if sections.empty?
-
-      "#{ name }#{ sections.map { Post.section_literal(_1) }.join }"
-    end
-  end
-
-  def self.section_literal section
-    "[#{ Post.ms_to_time(section.begin_ms) }-#{ section.end_ms ? Post.ms_to_time(section.end_ms) : '' }]"
-  end
-
-  def self.ms_to_time ms
-    total_s = ms / 1_000
-    s = total_s % 60
-    min = (total_s / 60) % 60
-    h = total_s / 3_600
-    remainder_ms = ms % 1_000
-
-    base =
-        if h.positive?
-          '%d:%02d:%02d' % [h, min, s]
-        else
-          '%d:%02d' % [min, s]
-        end
-
-    remainder_ms.positive? ? "#{ base }.#{ remainder_ms.to_s.rjust(3, '0') }" : base
-  end
+  def snapshot_tag_names = tags.joins(:tag_name).order('tag_names.name').pluck('tag_names.name')
 
   def snapshot_parent_post_ids = parents.order(:id).pluck(:id)
 
@@ -137,7 +74,12 @@ class Post < ApplicationRecord
   def resized_thumbnail!
     return unless thumbnail.attached?
 
-    thumbnail.attach(self.class.resized_thumbnail_attachment(StringIO.new(thumbnail.download)))
+    image = MiniMagick::Image.read(thumbnail.download)
+    image.resize '180x180'
+    thumbnail.purge
+    thumbnail.attach(io:            File.open(image.path),
+                     filename:      'resized_thumbnail.jpg',
+                     content_type:  'image/jpeg')
   end
 
   private

backend/app/models/post_tag.rb

@@ -10,12 +10,6 @@ class PostTag < ApplicationRecord
   belongs_to :created_user, class_name: 'User', optional: true
   belongs_to :deleted_user, class_name: 'User', optional: true
 
-  has_many :sections, -> { order(:begin_ms) }, class_name: 'PostTagSection',
-                                               foreign_key: [:post_id, :tag_id],
-                                               primary_key: [:post_id, :tag_id],
-                                               dependent: :delete_all,
-                                               inverse_of: :post_tag
-
   validates :post_id, presence: true
   validates :tag_id, presence: true
   validates :post_id, uniqueness: {

backend/app/models/post_tag_section.rb

@@ -1,20 +0,0 @@
-class PostTagSection < ApplicationRecord
-  self.primary_key = :post_id, :tag_id, :begin_ms
-
-  belongs_to :post
-  belongs_to :tag
-
-  belongs_to :post_tag, -> { kept }, foreign_key: [:post_id, :tag_id],
-                                     primary_key: [:post_id, :tag_id],
-                                     inverse_of: :sections,
-                                     optional: true
-
-  validates :post_id, presence: true
-  validates :tag_id, presence: true
-
-  validates :begin_ms, presence: true,
-                       numericality: { only_integer: true, greater_than_or_equal_to: 0 }
-
-  validates :end_ms, numericality: { only_integer: true, greater_than: :begin_ms },
-                     allow_nil: true
-end

backend/app/models/post_version.rb

@@ -5,7 +5,6 @@ class PostVersion < ApplicationRecord
   belongs_to :parent, class_name: 'Post', optional: true
 
   validates :url, presence: true
-  validates :video_ms, numericality: { only_integer: true, greater_than: 0 }, allow_nil: true
 
   validate :validate_original_created_range
 

backend/app/models/setting.rb

@@ -1,52 +1,7 @@
 class Setting < ApplicationRecord
-  THEMES = ['system', 'light', 'dark'].freeze
-
-  # These remain in the typed settings schema to preserve existing backend
-  # work. The common `/users/settings` page currently surfaces only `theme`.
-  AUTO_FETCH_MODES = ['auto', 'manual', 'off'].freeze
-  WIKI_EDITOR_MODES = ['split', 'write', 'preview'].freeze
-
-  STRING_ATTRIBUTES = [
-    'theme',
-    'auto_fetch_title',
-    'auto_fetch_thumbnail',
-    'wiki_editor_mode',
-  ].freeze
-  INTEGER_ATTRIBUTES = [].freeze
-  BOOLEAN_ATTRIBUTES = [].freeze
-  EDITABLE_ATTRIBUTES =
-      (STRING_ATTRIBUTES + INTEGER_ATTRIBUTES + BOOLEAN_ATTRIBUTES).freeze
-  TYPE_BY_ATTRIBUTE = {
-    'theme' => :string,
-    'auto_fetch_title' => :string,
-    'auto_fetch_thumbnail' => :string,
-    'wiki_editor_mode' => :string,
-  }.freeze
-
   belongs_to :user
 
   validates :user_id, presence: true
-  validates :user_id, uniqueness: true
-
-  validates :theme, inclusion: { in: THEMES }
-  validates :auto_fetch_title, inclusion: { in: AUTO_FETCH_MODES }
-  validates :auto_fetch_thumbnail, inclusion: { in: AUTO_FETCH_MODES }
-  validates :wiki_editor_mode, inclusion: { in: WIKI_EDITOR_MODES }
-
-  def self.defaults
-    {
-      theme: 'system',
-      auto_fetch_title: 'manual',
-      auto_fetch_thumbnail: 'manual',
-      wiki_editor_mode: 'split',
-    }
-  end
-
-  def self.serializable_attributes
-    EDITABLE_ATTRIBUTES.map(&:to_sym)
-  end
-
-  def serializable_hash(options = nil)
-    super({ only: self.class.serializable_attributes }.merge(options || { }))
-  end
+  validates :key, presence: true, length: { maximum: 255 }
+  validates :value, presence: true
 end

backend/app/models/tag.rb

@@ -8,25 +8,6 @@ class Tag < ApplicationRecord
     ;
   end
 
-  class DeprecatedTagNormalisationError < ArgumentError
-    attr_reader :tag_names
-
-    def initialize tag_names
-      @tag_names = Array(tag_names)
-      super('deprecated tags are not allowed')
-    end
-  end
-
-  class SectionLiteralParseError < ArgumentError
-    attr_reader :tag_name, :literal
-
-    def initialize tag_name, literal
-      @tag_name = tag_name
-      @literal = literal
-      super("invalid section literal for tag #{ tag_name }: #{ literal }")
-    end
-  end
-
   has_many :post_tags, inverse_of: :tag
   has_many :active_post_tags, -> { kept }, class_name: 'PostTag', inverse_of: :tag
   has_many :post_tags_with_discarded, -> { with_discarded }, class_name: 'PostTag'
@@ -77,7 +58,6 @@ class Tag < ApplicationRecord
   validate :nico_tag_name_must_start_with_nico
   validate :tag_name_must_be_canonical
   validate :category_must_be_deerjikist_with_deerjikists
-  validate :nico_tags_cannot_be_deprecated
 
   scope :nico_tags, -> { nico }
 
@@ -97,8 +77,6 @@ class Tag < ApplicationRecord
     (self.tag_name ||= build_tag_name).name = val
   end
 
-  def deprecated? = deprecated_at?
-
   def has_wiki = wiki_page.present?
 
   def material_id = materials.first&.id
@@ -114,61 +92,22 @@ class Tag < ApplicationRecord
 
   def self.normalise_tags! tag_names, with_tagme: true,
                                       with_no_deerjikist: true,
-                                      deny_nico: true,
-                                      deny_deprecated: false,
-                                      with_sections: false
+                                      deny_nico: true
     if deny_nico && tag_names.any? { |n| n.downcase.start_with?('nico:') }
       raise NicoTagNormalisationError
     end
 
-    sections = { }
     tags = tag_names.map do |name|
-      raw_name = name
       pf, cat = CATEGORY_PREFIXES.find { |p, _| name.downcase.start_with?(p) } || ['', nil]
-
-      name = name.sub(/\A#{ pf }/i, '')
-
-      sections_by_tag = []
-      while (match = name.match(/\A(\S*?)\[([^\[\]\s]*)-([^\[\]\s]*)\](\S*)\z/))
-        name = "#{ match[1] }#{ match[4] }"
-        next if match[2].empty? && match[3].empty?
-
-        sections_by_tag << normalise_section_range!(
-            begin_raw: match[2],
-            end_raw: match[3],
-            tag_name: name)
-      end
-
-      if name.include?('[') || name.include?(']')
-        raise SectionLiteralParseError.new(raw_name, raw_name)
-      end
-
-      name = TagName.canonicalise(name).first
-
+      name = TagName.canonicalise(name.sub(/\A#{ pf }/i, '')).first
       find_or_create_by_tag_name!(name, category: (cat || :general)).tap do |tag|
-        if deny_deprecated && tag.deprecated?
-          raise DeprecatedTagNormalisationError, [tag.name]
-        end
-
         tag.update!(category: cat) if cat && tag.category != cat
-        next if sections_by_tag.empty?
-
-        sections[tag.id] ||= []
-        sections[tag.id].concat(sections_by_tag)
-        sections[tag.id] = merge_section_ranges(sections[tag.id])
-        sections.delete(tag.id) if sections[tag.id] == [[0, nil]]
       end
     end
 
     tags << Tag.tagme if with_tagme && tags.size < 10 && tags.none?(Tag.tagme)
     tags << Tag.no_deerjikist if with_no_deerjikist && tags.all? { |t| !(t.deerjikist?) }
-    tags.uniq!(&:id)
-
-    if with_sections
-      { tags:, sections: }
-    else
-      tags
-    end
+    tags.uniq(&:id)
   end
 
   def self.expand_parent_tags tags
@@ -194,45 +133,6 @@ class Tag < ApplicationRecord
     (result + tags).uniq { |t| t.id }
   end
 
-  def self.normalise_section_range! begin_raw:, end_raw:, tag_name:
-    begin_ms = begin_raw.empty? ? 0 : time_to_ms!(begin_raw, tag_name:)
-    end_ms = end_raw.empty? ? nil : time_to_ms!(end_raw, tag_name:)
-
-    if end_ms
-      begin_ms, end_ms = end_ms, begin_ms if begin_ms > end_ms
-      end_ms = begin_ms + 1 if begin_ms == end_ms
-    end
-
-    [begin_ms, end_ms]
-  end
-
-  def self.merge_section_ranges ranges
-    sorted_ranges = ranges.sort_by { |begin_ms, end_ms| [begin_ms, end_ms || Float::INFINITY] }
-    merged = []
-
-    sorted_ranges.each do |begin_ms, end_ms|
-      if merged.empty?
-        merged << [begin_ms, end_ms]
-        next
-      end
-
-      last_begin_ms, last_end_ms = merged[-1]
-      if last_end_ms.nil? || begin_ms <= last_end_ms
-        merged[-1] = [last_begin_ms, merge_section_end(last_end_ms, end_ms)]
-      else
-        merged << [begin_ms, end_ms]
-      end
-    end
-
-    merged
-  end
-
-  def self.merge_section_end left_end_ms, right_end_ms
-    return nil if left_end_ms.nil? || right_end_ms.nil?
-
-    [left_end_ms, right_end_ms].max
-  end
-
   def self.find_or_create_by_tag_name! name, category:
     tn = TagName.find_undiscard_or_create_by!(name: name.to_s.strip)
     tn = tn.canonical if tn.canonical_id?
@@ -328,36 +228,4 @@ class Tag < ApplicationRecord
       errors.add :category, 'ニジラーと紐づいてゐるタグはニジラー・カテゴリである必要があります．'
     end
   end
-
-  def self.time_to_ms! str, tag_name:
-    match =
-        case str
-        when /\A(?<seconds>\d+)(?:\.(?<ms>\d{1,3}))?\z/
-          { hours: nil, minutes: nil, seconds: Regexp.last_match[:seconds],
-            ms: Regexp.last_match[:ms] }
-        when /\A(?<minutes>\d+):(?<seconds>[0-5]?\d)(?:\.(?<ms>\d{1,3}))?\z/
-          { hours: nil, minutes: Regexp.last_match[:minutes],
-            seconds: Regexp.last_match[:seconds],
-            ms: Regexp.last_match[:ms] }
-        when /\A(?<hours>\d+):(?<minutes>[0-5]?\d):(?<seconds>[0-5]?\d)(?:\.(?<ms>\d{1,3}))?\z/
-          { hours: Regexp.last_match[:hours],
-            minutes: Regexp.last_match[:minutes],
-            seconds: Regexp.last_match[:seconds],
-            ms: Regexp.last_match[:ms] }
-        end
-
-    raise SectionLiteralParseError.new(tag_name, str) unless match
-
-    total_s = match[:seconds].to_i
-    total_s += match[:minutes].to_i * 60 if match[:minutes]
-    total_s += match[:hours].to_i * 3_600 if match[:hours]
-
-    total_s * 1_000 + match[:ms].to_s.ljust(3, '0')[0, 3].to_i
-  end
-
-  def nico_tags_cannot_be_deprecated
-    if nico? && deprecated_at.present?
-      errors.add :deprecated_at, 'ニコタグは廃止できません．'
-    end
-  end
 end

backend/app/models/tag_implication.rb

@@ -6,7 +6,6 @@ class TagImplication < ApplicationRecord
   validates :parent_tag_id, presence: true
 
   validate :parent_tag_mustnt_be_itself
-  validate :parent_tag_mustnt_create_cycle
 
   private
 
@@ -15,27 +14,4 @@ class TagImplication < ApplicationRecord
       errors.add :parent_tag_id, '親タグは子タグと同一であってはなりません．'
     end
   end
-
-  def parent_tag_mustnt_create_cycle
-    return if tag_id.blank? || parent_tag_id.blank?
-    return if errors[:parent_tag_id].present?
-
-    seen = { }
-    stack = [parent_tag_id]
-
-    until stack.empty?
-      current_id = stack.pop
-      next if seen[current_id]
-
-      seen[current_id] = true
-
-      if current_id == tag_id
-        errors.add :parent_tag_id, '親タグに子孫タグを指定すると循環します．'
-        errors.add :base, 'タグの親子関係が循環します．'
-        return
-      end
-
-      stack.concat(TagImplication.where(tag_id: current_id).pluck(:parent_tag_id))
-    end
-  end
 end

backend/app/models/user.rb

@@ -7,8 +7,7 @@ class User < ApplicationRecord
 
   has_many :created_posts,
            class_name: 'Post', foreign_key: :uploaded_user_id, dependent: :nullify
-  has_one :setting, dependent: :destroy
-  has_many :theme_slots, class_name: 'UserThemeSlot', dependent: :destroy
+  has_many :settings
   has_many :user_ips, dependent: :destroy
   has_many :ip_addresses, through: :user_ips
   has_many :user_post_views, dependent: :destroy

backend/app/models/user_theme_slot.rb

@@ -1,27 +0,0 @@
-class UserThemeSlot < ApplicationRecord
-  BASE_THEMES = ['light', 'dark'].freeze
-  SLOT_NOS = [1, 2, 3].freeze
-
-  belongs_to :user
-
-  validates :user_id, presence: true
-  validates :base_theme, presence: true, inclusion: { in: BASE_THEMES }
-  validates :slot_no, presence: true, inclusion: { in: SLOT_NOS }
-  validates :tokens, presence: true
-  validates :user_id, uniqueness: { scope: [:base_theme, :slot_no] }
-
-  validate :tokens_must_be_object
-
-  def serializable_hash(options = nil)
-    hash = { only: [:base_theme, :slot_no, :tokens, :created_at, :updated_at] }
-    super(hash.merge(options || {}))
-  end
-
-  private
-
-  def tokens_must_be_object
-    return if tokens.is_a?(Hash)
-
-    errors.add(:tokens, 'は JSON object で指定してください．')
-  end
-end

backend/app/models/version_record.rb

@@ -1,23 +1,15 @@
 module VersionRecord
   extend ActiveSupport::Concern
 
-  DEFAULT_EVENT_TYPE_MAP = { create: 'create',
-                             update: 'update',
-                             discard: 'discard',
-                             restore: 'restore' }.freeze
-
   def readonly? = persisted?
 
   included do
-    event_type_map = if const_defined?(:EVENT_TYPE_MAP, false)
-                       const_get(:EVENT_TYPE_MAP)
-                     else
-                       DEFAULT_EVENT_TYPE_MAP
-                     end
-
     belongs_to :created_by_user, class_name: 'User', optional: true
 
-    enum :event_type, event_type_map, prefix: true, validate: true
+    enum :event_type, { create: 'create',
+                        update: 'update',
+                        discard: 'discard',
+                        restore: 'restore' }, prefix: true, validate: true
 
     validates :version_no, presence: true, numericality: { only_integer: true, greater_than: 0 }
     validates :event_type, presence: true

backend/app/models/wiki_page.rb

@@ -22,7 +22,6 @@ class WikiPage < ApplicationRecord
   validates :body, presence: true
 
   def title = tag_name.name
-  def deprecated_at = tag_name.tag&.deprecated_at
 
   def title= val
     (self.tag_name ||= build_tag_name).name = val

backend/app/representations/material_repr.rb

@@ -2,9 +2,7 @@
 
 
 module MaterialRepr
-  BASE = { only: [:id, :url, :version_no, :source_kind, :source_uri,
-                  :source_path, :source_file_id, :normalized_source_key,
-                  :created_at, :updated_at],
+  BASE = { only: [:id, :url, :created_at, :updated_at],
            methods: [:content_type],
            include: { tag: TagRepr::BASE,
                       created_by_user: UserRepr::BASE,
@@ -17,93 +15,10 @@ module MaterialRepr
         file: if material.file.attached?
                 Rails.application.routes.url_helpers.rails_storage_proxy_url(
                     material.file, host:)
-              end,
-        thumbnail: thumbnail_url(material, host:),
-        thumbnail_fallback_text: thumbnail_fallback_text(material),
-        thumbnail_fallback_kind: thumbnail_fallback_kind(material),
-        media_kind: media_kind(material),
-        file_byte_size: material.file_byte_size,
-        export_paths: export_paths(material),
-        export_items: export_items(material))
+              end)
   end
 
   def many materials, host:
     materials.map { |m| base(m, host:) }
   end
-
-  def list material, host:
-    { id: material.id,
-      version_no: material.version_no,
-      url: material.url,
-      source_kind: material.source_kind,
-      source_uri: material.source_uri,
-      source_path: material.source_path,
-      source_file_id: material.source_file_id,
-      normalized_source_key: material.normalized_source_key,
-      tag: compact_tag(material.tag),
-      thumbnail: thumbnail_url(material, host:),
-      thumbnail_fallback_text: thumbnail_fallback_text(material),
-      thumbnail_fallback_kind: thumbnail_fallback_kind(material),
-      media_kind: media_kind(material),
-      content_type: material.content_type,
-      file_byte_size: material.file_byte_size,
-      created_at: material.created_at,
-      updated_at: material.updated_at,
-      export_paths: export_paths(material),
-      export_items: export_items(material) }
-  end
-
-  def list_many materials, host:
-    materials.map { |m| list(m, host:) }
-  end
-
-  def export_paths material
-    material.material_export_items.each_with_object({ }) do |item, hash|
-      hash[item.profile] = item.enabled ? item.export_path : ''
-    end
-  end
-
-  def export_items material
-    material.material_export_items.map do |item|
-      { id: item.id,
-        profile: item.profile,
-        export_path: item.export_path,
-        enabled: item.enabled }
-    end
-  end
-
-  def thumbnail_url material, host:
-    return nil unless material.thumbnail.attached?
-
-    Rails.application.routes.url_helpers.rails_storage_proxy_url(
-        material.thumbnail, host:)
-  end
-
-  def thumbnail_fallback_text material
-    material.tag&.name || material.created_at&.strftime('%Y-%m-%d')
-  end
-
-  def thumbnail_fallback_kind material
-    material.tag.present? ? 'tag_name' : 'created_at'
-  end
-
-  def media_kind material
-    return 'url_only' unless material.file.attached?
-
-    content_type = material.file.blob.content_type.to_s
-    return 'image' if content_type.start_with?('image/')
-    return 'video' if content_type.start_with?('video/')
-    return 'audio' if content_type.start_with?('audio/')
-
-    'file_other'
-  end
-
-  def compact_tag tag
-    return nil unless tag
-
-    { id: tag.id,
-      name: tag.name,
-      category: tag.category,
-      deprecated_at: tag.deprecated_at }
-  end
 end

backend/app/representations/post_repr.rb

@@ -8,7 +8,6 @@ module PostRepr
       :url,
       :title,
       :thumbnail_base,
-      :video_ms,
       :original_created_from,
       :original_created_before,
       :created_at,
@@ -19,7 +18,7 @@ module PostRepr
 
   def base post, current_user = nil
     json = common(post)
-    json['tags'] = tag_json(post)
+    json['tags'] = tag_json(post.tags)
     json['uploaded_user'] = post.uploaded_user && UserRepr.base(post.uploaded_user)
     json['viewed'] = current_user ? current_user.viewed?(post) : false
     json
@@ -53,16 +52,8 @@ module PostRepr
                .merge('thumbnail' => thumbnail_url(post))
   end
 
-  def tag_json post
-    post
-        .active_post_tags
-        .reject { _1.tag.deprecated? }
-        .sort_by { _1.tag.name }
-        .map { |post_tag|
-      TagRepr.inline(post_tag.tag).merge(
-          'children' => [],
-          'sections' => post_tag.sections.as_json(only: [:begin_ms, :end_ms]))
-    }
+  def tag_json tags
+    tags.map { |tag| TagRepr.inline(tag) }
   end
 
   def thumbnail_url post

backend/app/representations/tag_repr.rb

@@ -2,7 +2,7 @@
 
 
 module TagRepr
-  BASE = { only: [:id, :category, :post_count, :created_at, :updated_at, :deprecated_at],
+  BASE = { only: [:id, :category, :post_count, :created_at, :updated_at],
            methods: [:name, :has_wiki, :material_id, :has_deerjikists] }.freeze
 
   module_function

backend/app/representations/wiki_page_repr.rb

@@ -2,7 +2,7 @@
 
 
 module WikiPageRepr
-  BASE = { methods: [:title, :deprecated_at] }.freeze
+  BASE = { methods: [:title] }.freeze
 
   module_function
 

backend/app/services/gekanator/ai_run_budget.rb

@@ -1,22 +0,0 @@
-module Gekanator
-  class AiRunBudget
-    MONTHLY_LIMIT_JPY = BigDecimal('450').freeze
-    MAX_RUN_ESTIMATED_COST_JPY = BigDecimal('5').freeze
-
-    def self.remaining_monthly_budget_jpy
-      MONTHLY_LIMIT_JPY - monthly_cost_jpy
-    end
-
-    def self.monthly_cost_jpy
-      GekanatorAiRun.this_month.sum(:estimated_cost_jpy)
-    end
-
-    def self.exceeded?
-      monthly_cost_jpy >= MONTHLY_LIMIT_JPY
-    end
-
-    def self.exceeded_after_next_run?
-      monthly_cost_jpy + MAX_RUN_ESTIMATED_COST_JPY >= MONTHLY_LIMIT_JPY
-    end
-  end
-end

backend/app/services/gekanator/question_suggestion_ai_converter.rb

@@ -1,168 +0,0 @@
-module Gekanator
-  class QuestionSuggestionAiConverter
-    # Temporary heuristic converter for #361.
-    # This creates pending ai_generated questions without external LLM calls;
-    # accepted questions are still distributed only after admin approval.
-    TITLE_LENGTH_RE = /\Aタイトルは\s*(\d+)\s*文字以上[？?]\z/
-    ORIGINAL_YEAR_RE = /\Aオリジナルの投稿年は\s*(\d{4})\s*年[？?]\z/
-    ORIGINAL_MONTH_RE = /\Aオリジナルの投稿月は\s*(\d{1,2})\s*月[？?]\z/
-    ORIGINAL_MONTH_DAY_RE = /\Aオリジナルの投稿日は\s*(\d{1,2})\s*月\s*(\d{1,2})\s*日[？?]\z/
-    TITLE_CONTAINS_RE = /\A題名に「(.+?)」が含まれる[？?]\z/
-    SOURCE_RE = /\A(.+?)\s+の投稿を思[ひい]浮かべて[ゐい]る[？?]\z/
-
-    def self.call(...) = new(...).call
-
-    def initialize suggestion:, user:
-      @suggestion = suggestion
-      @user = user
-    end
-
-    def call
-      suggestion.with_lock do
-        existing = existing_generated_question
-        return existing if existing
-
-        run = suggestion.gekanator_ai_runs.create!(
-            model: 'heuristic_converter_v1',
-            status: 'running',
-            input_tokens: 0,
-            output_tokens: 0,
-            estimated_cost_jpy: 0)
-
-        question_attributes = build_question
-        question =
-            question_attributes &&
-            GekanatorQuestion.create!(
-                **question_attributes,
-                source: 'ai_generated',
-                status: 'pending',
-                gekanator_question_suggestion: suggestion,
-                created_by: user)
-
-        run.update!(status: question ? 'succeeded' : 'failed')
-        question
-      end
-    rescue => error
-      run&.update!(status: 'failed') if run&.persisted? && run.status != 'failed'
-      raise error
-    end
-
-    private
-
-    attr_reader :suggestion, :user
-
-    def existing_generated_question
-      suggestion
-          .gekanator_questions
-          .where(source: 'ai_generated')
-          .order(id: :desc)
-          .first
-    end
-
-    def build_question
-      text = normalized_text
-      return nil if text.blank?
-
-      structured_question_for(text) || post_similarity_question_for(text)
-    end
-
-    def normalized_text
-      suggestion.question_text.to_s.gsub(/[[:space:]]+/, ' ').strip
-    end
-
-    def structured_question_for text
-      case text
-      when TITLE_LENGTH_RE
-        length = Regexp.last_match(1).to_i
-        return nil if length <= 0
-
-        {
-          text:,
-          kind: 'title',
-          condition: {
-            type: 'title-length-at-least',
-            length:
-          },
-          priority_weight: 0.95
-        }
-      when /\A題名に英数字が混じって[ゐい]る[？?]\z/
-        {
-          text: '題名に英数字が混じってゐる?',
-          kind: 'title',
-          condition: { type: 'title-has-ascii' },
-          priority_weight: 0.95
-        }
-      when ORIGINAL_YEAR_RE
-        year = Regexp.last_match(1).to_i
-        {
-          text:,
-          kind: 'original_date',
-          condition: { type: 'original-year', year: },
-          priority_weight: 0.95
-        }
-      when ORIGINAL_MONTH_RE
-        month = Regexp.last_match(1).to_i
-        return nil unless month.between?(1, 12)
-
-        {
-          text:,
-          kind: 'original_date',
-          condition: { type: 'original-month', month: },
-          priority_weight: 0.95
-        }
-      when ORIGINAL_MONTH_DAY_RE
-        month = Regexp.last_match(1).to_i
-        day = Regexp.last_match(2).to_i
-        return nil unless month.between?(1, 12) && day.between?(1, 31)
-
-        {
-          text:,
-          kind: 'original_date',
-          condition: {
-            type: 'original-month-day',
-            monthDay: "#{ month }-#{ day }"
-          },
-          priority_weight: 0.95
-        }
-      when TITLE_CONTAINS_RE
-        title_text = Regexp.last_match(1).to_s.strip
-        return nil if title_text.blank?
-
-        {
-          text: "題名に「#{ title_text }」が含まれる?",
-          kind: 'title',
-          condition: { type: 'title-contains', text: title_text },
-          priority_weight: 0.95
-        }
-      when SOURCE_RE
-        host = Regexp.last_match(1).to_s.strip
-        return nil if host.blank?
-
-        {
-          text:,
-          kind: 'source',
-          condition: { type: 'source', host: },
-          priority_weight: 0.95
-        }
-      else
-        nil
-      end
-    end
-
-    def post_similarity_question_for text
-      return nil if suggestion.answer == 'unknown'
-
-      {
-        text:,
-        kind: 'post_similarity',
-        condition: {
-          type: 'post-similarity',
-          postId: suggestion.gekanator_game.correct_post_id,
-          answer: suggestion.answer,
-          threshold: 0.65
-        },
-        priority_weight: 1.0
-      }
-    end
-  end
-end

backend/app/services/gekanator/question_suggestion_promoter.rb

@@ -1,52 +0,0 @@
-module Gekanator
-  class QuestionSuggestionPromoter
-    def self.call(...) = new(...).call
-
-    def initialize suggestion:, user:
-      @suggestion = suggestion
-      @user = user
-    end
-
-    def call
-      suggestion.with_lock do
-        return promoted_question if suggestion.processed?
-        return suggestion if suggestion.answer == 'unknown'
-
-        question = GekanatorQuestion.create!(
-            text: suggestion.question_text,
-            kind: 'post_similarity',
-            source: 'user_suggested',
-            status: 'accepted',
-            priority_weight: 1.2,
-            condition: {
-              type: 'post-similarity',
-              postId: suggestion.gekanator_game.correct_post_id,
-              answer: suggestion.answer,
-              threshold: 0.65
-            },
-            gekanator_question_suggestion: suggestion,
-            created_by: user)
-        example =
-            GekanatorQuestionExample.new(
-                gekanator_question: question,
-                post: suggestion.gekanator_game.correct_post,
-                user: user)
-        example.record_answer!(
-            answer: suggestion.answer,
-            source: 'initial_suggestion',
-            gekanator_game: suggestion.gekanator_game)
-        example.save!
-        suggestion.update!(processed: true)
-        question
-      end
-    end
-
-    private
-
-    attr_reader :suggestion, :user
-
-    def promoted_question
-      suggestion.gekanator_questions.order(id: :desc).first
-    end
-  end
-end

backend/app/services/google_drive/api_client.rb

@@ -1,233 +0,0 @@
-require 'json'
-require 'jwt'
-require 'net/http'
-require 'openssl'
-require 'tempfile'
-require 'uri'
-
-
-module GoogleDrive
-  class ApiClient
-    DRIVE_ENDPOINT = 'https://www.googleapis.com/drive/v3'
-    TOKEN_ENDPOINT = 'https://oauth2.googleapis.com/token'
-    FOLDER_MIME_TYPE = 'application/vnd.google-apps.folder'
-    NATIVE_FILE_MIME_TYPE_PREFIX = 'application/vnd.google-apps.'
-    DRIVE_SCOPE = 'https://www.googleapis.com/auth/drive.readonly'
-
-    def initialize service_account_email: ENV['GOOGLE_DRIVE_SERVICE_ACCOUNT_EMAIL'],
-                   private_key: ENV['GOOGLE_DRIVE_PRIVATE_KEY'],
-                   private_key_path: ENV['GOOGLE_DRIVE_PRIVATE_KEY_PATH'],
-                   subject: ENV['GOOGLE_DRIVE_SUBJECT']
-      @service_account_email = service_account_email.to_s
-      @private_key = load_private_key(private_key, private_key_path)
-      @subject = subject.to_s.presence
-      @access_token = nil
-    end
-
-    def list_material_files_under_folder folder_id
-      files = []
-      each_material_file_under_folder(folder_id) { |entry| files << entry }
-      files
-    end
-
-    def each_material_file_under_folder folder_id
-      return enum_for(__method__, folder_id) unless block_given?
-
-      walk_folder(folder_id, nil) do |entry, relative_path|
-        next if entry['mimeType'] == FOLDER_MIME_TYPE
-        next if native_file?(entry['mimeType'])
-
-        yield build_file_entry(entry, relative_path)
-      end
-    end
-
-    def fetch_material_file file_id
-      metadata = get_file(file_id)
-      return nil if native_file?(metadata['mimeType'])
-
-      build_file_entry(metadata, metadata['name'])
-    end
-
-    def download_to_tempfile file_id, filename:
-      tempfile = Tempfile.new(['material-sync', File.extname(filename.to_s)])
-      tempfile.binmode
-      request_binary("/files/#{ file_id }",
-                     { alt: 'media', supportsAllDrives: true }) do |chunk|
-        tempfile.write(chunk.b)
-      end
-      tempfile.rewind
-      tempfile
-    rescue StandardError
-      tempfile&.close!
-      raise
-    end
-
-    def extract_file_id value
-      raw = value.to_s.strip
-      return nil if raw.blank?
-      return raw unless raw.include?('/')
-
-      uri = URI.parse(raw)
-      return uri.query.to_s[%r{(?:^|&)id=([^&]+)}, 1] if uri.query.present?
-      return uri.path[%r{/folders/([^/]+)}, 1] if uri.path.include?('/folders/')
-
-      uri.path[%r{/d/([^/]+)}, 1]
-    rescue URI::InvalidURIError
-      nil
-    end
-
-    private
-
-    def walk_folder folder_id, prefix, &block
-      list_children(folder_id).each do |entry|
-        relative_path = MaterialSyncExportPath.build(prefix:,
-                                                     relative_path: entry['name'])
-        if entry['mimeType'] == FOLDER_MIME_TYPE
-          walk_folder(entry['id'], relative_path, &block)
-          next
-        end
-
-        block.call(entry, relative_path)
-      end
-    end
-
-    def build_file_entry entry, relative_path
-      { id: entry['id'],
-        name: entry['name'],
-        mime_type: entry['mimeType'],
-        relative_path: MaterialSyncExportPath.normalize_path(relative_path),
-        sha256_checksum: entry['sha256Checksum'],
-        web_view_link: entry['webViewLink'],
-        web_content_link: entry['webContentLink'] }
-    end
-
-    def list_children folder_id
-      files = []
-      page_token = nil
-
-      loop do
-        response =
-            request_json('/files', {
-                q: "'#{ folder_id }' in parents and trashed = false",
-                fields: 'nextPageToken,files(id,name,mimeType,sha256Checksum,' \
-                        'webViewLink,webContentLink)',
-                orderBy: 'folder,name',
-                pageSize: 1000,
-                supportsAllDrives: true,
-                includeItemsFromAllDrives: true,
-                pageToken: page_token }.compact)
-        files.concat(response.fetch('files'))
-        page_token = response['nextPageToken']
-        break if page_token.blank?
-      end
-
-      files
-    end
-
-    def get_file file_id
-      request_json("/files/#{ file_id }",
-                   fields: 'id,name,mimeType,sha256Checksum,webViewLink,webContentLink',
-                   supportsAllDrives: true)
-    end
-
-    def request_json path, params = {}
-      response = request(:get, path, params:)
-      unless response.is_a?(Net::HTTPSuccess)
-        raise "Google Drive API error: #{ response.code } #{ response.body }"
-      end
-
-      JSON.parse(response.body)
-    end
-
-    def request_binary path, params = {}
-      request(:get, path, params:) do |response|
-        unless response.is_a?(Net::HTTPSuccess)
-          raise "Google Drive download error: #{ response.code } #{ response.body }"
-        end
-
-        response.read_body do |chunk|
-          yield chunk.b
-        end
-      end
-    end
-
-    def request method, path, params: nil
-      uri = URI(DRIVE_ENDPOINT + path)
-      uri.query = URI.encode_www_form(params) if params.present?
-
-      klass =
-          case method
-          when :get
-            Net::HTTP::Get
-          else
-            raise ArgumentError, "Unsupported Google Drive request method: #{ method }"
-          end
-      request = klass.new(uri)
-      request['Authorization'] = "Bearer #{ access_token }"
-
-      Net::HTTP.start(uri.host,
-                      uri.port,
-                      use_ssl: true,
-                      open_timeout: 10,
-                      read_timeout: 60) do |http|
-        if block_given?
-          http.request(request) do |response|
-            return yield response
-          end
-        else
-          http.request(request)
-        end
-      end
-    end
-
-    def access_token
-      @access_token ||= fetch_access_token
-    end
-
-    def fetch_access_token
-      raise 'GOOGLE_DRIVE_SERVICE_ACCOUNT_EMAIL is required' if @service_account_email.blank?
-      raise 'Google Drive private key is required' if @private_key.blank?
-
-      payload = { iss: @service_account_email,
-                  scope: DRIVE_SCOPE,
-                  aud: TOKEN_ENDPOINT,
-                  exp: 1.hour.from_now.to_i,
-                  iat: Time.current.to_i }
-      payload[:sub] = @subject if @subject.present?
-
-      assertion = JWT.encode(payload, @private_key, 'RS256')
-      uri = URI(TOKEN_ENDPOINT)
-      request = Net::HTTP::Post.new(uri)
-      request.set_form_data(
-          grant_type: 'urn:ietf:params:oauth:grant-type:jwt-bearer',
-          assertion:)
-
-      response =
-          Net::HTTP.start(uri.host,
-                          uri.port,
-                          use_ssl: true,
-                          open_timeout: 10,
-                          read_timeout: 30) do |http|
-            http.request(request)
-          end
-      unless response.is_a?(Net::HTTPSuccess)
-        raise "Google OAuth error: #{ response.code } #{ response.body }"
-      end
-
-      JSON.parse(response.body).fetch('access_token')
-    end
-
-    def load_private_key private_key, private_key_path
-      raw = private_key.to_s
-      raw = raw.gsub('\n', "\n") if raw.present?
-      raw = File.read(private_key_path) if raw.blank? && private_key_path.present?
-      return nil if raw.blank?
-
-      OpenSSL::PKey::RSA.new(raw)
-    end
-
-    def native_file? mime_type
-      mime_type.to_s.start_with?(NATIVE_FILE_MIME_TYPE_PREFIX)
-    end
-  end
-end

backend/app/services/material_file_sha256.rb

@@ -1,57 +0,0 @@
-require 'digest'
-require 'json'
-
-class MaterialFileSha256
-  def self.blob_metadata blob
-    metadata = blob.metadata
-    return metadata if metadata.is_a?(Hash)
-    return { } if metadata.blank?
-
-    JSON.parse(metadata)
-  rescue JSON::ParserError
-    { }
-  end
-
-  def self.metadata_sha256 blob
-    blob_metadata(blob)['sha256'].presence
-  end
-
-  def self.assign_metadata_sha256! blob, sha256
-    return if sha256.blank?
-
-    metadata = blob_metadata(blob)
-    metadata['sha256'] = sha256
-    blob.metadata = metadata
-    blob.save! if blob.changed?
-  end
-
-  def self.from_blob blob, allow_download: false
-    sha256 = metadata_sha256(blob)
-    return sha256 if sha256.present?
-    return nil unless allow_download
-
-    begin
-      blob.open do |file|
-        sha256 = Digest::SHA256.file(file.path).hexdigest
-        assign_metadata_sha256!(blob, sha256)
-        sha256
-      end
-    rescue ActiveStorage::FileNotFoundError, ArgumentError => error
-      Rails.logger.warn(
-          "MaterialFileSha256.from_blob failed for blob_id=#{blob.id}: " \
-          "#{error.class}: #{error.message}",
-      )
-      nil
-    end
-  end
-
-  def self.from_upload upload
-    tempfile = upload&.tempfile
-    return nil unless tempfile
-
-    tempfile.rewind
-    Digest::SHA256.file(tempfile.path).hexdigest.tap do
-      tempfile.rewind
-    end
-  end
-end

backend/app/services/material_import_block_matcher.rb

@@ -1,7 +0,0 @@
-class MaterialImportBlockMatcher
-  def self.match_for_sha256 sha256
-    return nil if sha256.blank?
-
-    MaterialImportBlock.find_by(match_kind: 'sha256', sha256:)
-  end
-end

backend/app/services/material_sync_export_path.rb

@@ -1,56 +0,0 @@
-class MaterialSyncExportPath
-  class << self
-    def build prefix: nil, relative_path: nil, filename: nil, source_file_id: nil
-      path = normalize_path(relative_path)
-      path = fallback_filename(filename, source_file_id) if path.blank?
-
-      normalized_prefix = normalize_path(prefix)
-      return path if normalized_prefix.blank?
-      return normalized_prefix if path.blank?
-
-      [normalized_prefix, path].join('/')
-    end
-
-    def normalize_path path
-      raw = path.to_s.delete("\0").tr('\\', '/').strip
-      raw = raw.sub(%r{\A[A-Za-z]:/+}, '')
-      raw = raw.sub(%r{\A/+}, '')
-      return nil if raw.blank?
-
-      segments = raw.split('/').filter_map do |segment|
-        normalized = normalize_segment(segment)
-        normalized.presence
-      end
-      return nil if segments.empty?
-
-      segments.join('/')
-    end
-
-    def uniquify path, source_file_id
-      normalized = normalize_path(path)
-      return normalized if normalized.blank? || source_file_id.blank?
-
-      ext = File.extname(normalized)
-      base = ext.present? ? normalized.delete_suffix(ext) : normalized
-      "#{ base }--#{ source_file_id }#{ ext }"
-    end
-
-    private
-
-    def fallback_filename filename, source_file_id
-      name = normalize_path(filename)
-      return name if name.present?
-      return nil if source_file_id.blank?
-
-      source_file_id.to_s
-    end
-
-    def normalize_segment segment
-      cleaned = segment.to_s.delete("\0").tr('\\/', '_').strip
-      return nil if cleaned.blank? || cleaned == '.'
-      return '__' if cleaned == '..'
-
-      cleaned
-    end
-  end
-end

backend/app/services/material_sync_importer.rb

@@ -1,259 +0,0 @@
-require 'digest'
-
-class MaterialSyncImporter
-  Result = Struct.new(:material, :action, :suppressed, :suppression, keyword_init: true)
-
-  def self.import! attributes
-    new(attributes).import!
-  end
-
-  def initialize attributes
-    @attributes = attributes
-  end
-
-  def import!
-    source = source_attributes
-    key = normalized_source_key(source)
-    raise ArgumentError, 'normalized_source_key is required for material sync' if key.blank?
-
-    suppression = suppression_for(source)
-    if suppression
-      return Result.new(material: nil,
-                        action: :suppressed,
-                        suppressed: true,
-                        suppression:)
-    end
-
-    material =
-        Material
-        .unscoped
-        .find_or_initialize_by(normalized_source_key: key)
-    if unchanged?(material, source)
-      return Result.new(material:,
-                        action: :unchanged,
-                        suppressed: false,
-                        suppression: nil)
-    end
-
-    event_type =
-        if material.new_record?
-          :create
-        elsif material.discarded?
-          :restore
-        else
-          :update
-        end
-    uploaded_blob = uploaded_blob!
-    if @import_block
-      return Result.new(material: nil,
-                        action: :suppressed,
-                        suppressed: true,
-                        suppression: @import_block)
-    end
-
-    Material.transaction do
-      if material.persisted?
-        MaterialVersionRecorder.ensure_snapshot!(material,
-                                                 created_by_user: @attributes[:updated_by_user])
-      end
-      material.assign_attributes(material_attributes_for(material).merge(source))
-      material.discarded_at = nil if material.respond_to?(:discarded_at=)
-      material.file.attach(uploaded_blob) if uploaded_blob
-      material.save!
-      upsert_export_item!(material)
-      MaterialVersionRecorder.record!(material:,
-                                      event_type:,
-                                      created_by_user: @attributes[:updated_by_user])
-    end
-    MaterialThumbnailGenerator.generate!(material)
-
-    Result.new(material:,
-               action: event_type == :create ? :imported : :updated,
-               suppressed: false,
-               suppression: nil)
-  rescue StandardError
-    uploaded_blob&.purge_later
-    raise
-  ensure
-    close_tempfile!
-  end
-
-  private
-
-  def source_attributes
-    { source_kind: @attributes[:source_kind],
-      source_uri: @attributes[:source_uri],
-      source_path: @attributes[:source_path],
-      source_file_id: @attributes[:source_file_id] }
-  end
-
-  def normalized_source_key source
-    MaterialSyncSuppression.normalize_source_key(source_kind: source[:source_kind],
-                                                 source_uri: source[:source_uri],
-                                                 source_path: source[:source_path],
-                                                 source_file_id: source[:source_file_id])
-  end
-
-  def material_attributes_for material
-    attrs =
-        @attributes
-        .except(:source_kind, :source_uri, :source_path, :source_file_id,
-                :file_blob, :file_tempfile, :file_downloader,
-                :filename, :content_type,
-                :file_sha256, :export_path, :profile, :tag, :url)
-
-    if material.new_record?
-      attrs[:tag] = @attributes[:tag] if @attributes.key?(:tag)
-      attrs[:url] = @attributes[:url] if @attributes.key?(:url)
-      return attrs
-    end
-
-    if @attributes.key?(:tag) && @attributes[:tag].present?
-      attrs[:tag] = @attributes[:tag]
-    end
-    if @attributes.key?(:url) && @attributes[:url].present?
-      attrs[:url] = @attributes[:url]
-    end
-
-    attrs
-  end
-
-  def suppression_for source
-    if source[:source_kind] == 'google_drive_file' && source[:source_path].present?
-      return MaterialSyncSuppressionMatcher.match_google_drive_candidate(
-          drive_file_id: source[:source_file_id],
-          relative_path: source[:source_path])
-    end
-
-    MaterialSyncSuppressionMatcher.match(**source)
-  end
-
-  def uploaded_blob!
-    return @attributes[:file_blob] if @attributes[:file_blob]
-
-    tempfile = upload_tempfile
-    return nil unless tempfile
-
-    tempfile.rewind
-    file_sha256 = @attributes[:file_sha256] || Digest::SHA256.file(tempfile.path).hexdigest
-    @attributes[:file_sha256] = file_sha256
-
-    @import_block = MaterialImportBlockMatcher.match_for_sha256(file_sha256)
-    if @import_block
-      tempfile.rewind
-      return nil
-    end
-
-    blob = ActiveStorage::Blob.create_and_upload!(
-        io: tempfile,
-        filename: @attributes[:filename],
-        content_type: @attributes[:content_type])
-    MaterialFileSha256.assign_metadata_sha256!(blob, file_sha256)
-    tempfile.rewind
-    blob
-  end
-
-  def upload_tempfile
-    return @upload_tempfile if defined?(@upload_tempfile)
-
-    @upload_tempfile = @attributes[:file_tempfile]
-    if @upload_tempfile.blank? && @attributes[:file_downloader]
-      @upload_tempfile = @attributes[:file_downloader].call
-    end
-    @upload_tempfile
-  end
-
-  def upsert_export_item! material
-    export_path = resolved_export_path(material)
-    return if export_path.blank?
-
-    item = material.material_export_items.find_or_initialize_by(profile: effective_profile)
-    item.export_path = export_path
-    item.enabled = true
-    item.created_by_user ||= @attributes[:created_by_user]
-    item.save!
-  end
-
-  def export_path_taken_by_other? material, profile, export_path
-    MaterialExportItem
-      .where(profile:, export_path:)
-      .where.not(material_id: material.id)
-      .exists?
-  end
-
-  def close_tempfile!
-    tempfile = upload_tempfile
-    return unless tempfile
-
-    tempfile.close! unless tempfile.closed?
-  rescue StandardError
-    nil
-  end
-
-  def unchanged? material, source
-    return false if material.new_record? || material.discarded?
-    return false unless same_source_attributes?(material, source)
-    return false unless same_export_path?(material)
-    return false unless same_material_attributes?(material)
-
-    same_file_snapshot?(material)
-  end
-
-  def same_source_attributes? material, source
-    material.source_kind == source[:source_kind] \
-      && material.source_uri == source[:source_uri] \
-      && material.source_path == source[:source_path] \
-      && material.source_file_id == source[:source_file_id]
-  end
-
-  def same_export_path? material
-    expected = resolved_export_path(material)
-    current = material.material_export_items.find { |item| item.profile == effective_profile }
-
-    return current.blank? if expected.blank?
-
-    current&.enabled && current.export_path == expected
-  end
-
-  def same_material_attributes? material
-    same_tag_attribute?(material) && same_url_attribute?(material)
-  end
-
-  def same_file_snapshot? material
-    expected_sha256 = @attributes[:file_sha256].to_s.presence
-
-    if expected_sha256.present?
-      return false unless material.file.attached?
-
-      return MaterialFileSha256.metadata_sha256(material.file.blob) == expected_sha256
-    end
-
-    !material.file.attached?
-  end
-
-  def effective_profile
-    @attributes[:profile].presence || 'legacy_drive'
-  end
-
-  def resolved_export_path material
-    export_path = @attributes[:export_path].to_s.strip
-    return export_path if export_path.blank?
-    return export_path unless export_path_taken_by_other?(material, effective_profile, export_path)
-
-    MaterialSyncExportPath.uniquify(export_path, @attributes[:source_file_id])
-  end
-
-  def same_tag_attribute? material
-    return true unless @attributes.key?(:tag)
-    return true if @attributes[:tag].blank?
-
-    material.tag_id == @attributes[:tag].id
-  end
-
-  def same_url_attribute? material
-    return true unless @attributes.key?(:url)
-    return true if @attributes[:url].blank?
-
-    material.url == @attributes[:url]
-  end
-end

backend/app/services/material_sync_runner.rb

@@ -1,251 +0,0 @@
-class MaterialSyncRunner
-  Result = Struct.new(:imported, :updated, :unchanged, :suppressed, :failed,
-                      :errors, keyword_init: true)
-
-  def self.sync_enabled!
-    results = MaterialSyncSource.enabled.order(:id).map { |source| new(source).sync! }
-
-    Result.new(imported: results.sum(&:imported),
-               updated: results.sum(&:updated),
-               unchanged: results.sum(&:unchanged),
-               suppressed: results.sum(&:suppressed),
-               failed: results.sum(&:failed),
-               errors: results.flat_map(&:errors))
-  end
-
-  def initialize source
-    @source = source
-  end
-
-  def sync!
-    result = Result.new(imported: 0, updated: 0, unchanged: 0,
-                        suppressed: 0, failed: 0, errors: [])
-
-    if @source.source_kind == 'google_drive_path'
-      sync_google_drive_path!(result)
-    else
-      candidates.each do |candidate|
-        next if candidate.blank?
-
-        sync_candidate!(candidate, result)
-      end
-    end
-
-    @source.update!(last_synced_at: Time.current)
-    log_result(result)
-    result
-  rescue NotImplementedError, StandardError => e
-    result.failed += 1
-    result.errors << { source_id: @source.id, error: e.message }
-    log_result(result)
-    result
-  end
-
-  private
-
-  def candidates
-    case @source.source_kind
-    when 'uri'
-      [uri_candidate]
-    when 'google_drive_file'
-      [google_drive_file_candidate]
-    when 'legacy_drive_path'
-      raise NotImplementedError, 'legacy_drive_path material sync is not implemented'
-    else
-      raise NotImplementedError, "Unsupported material sync source_kind: #{ @source.source_kind }"
-    end
-  end
-
-  def uri_candidate
-    { source_kind: @source.source_kind,
-      source_uri: @source.source_uri,
-      source_path: @source.source_path,
-      source_file_id: @source.source_file_id,
-      url: @source.source_uri,
-      tag: nil,
-      created_by_user: @source.created_by_user,
-      updated_by_user: @source.updated_by_user || @source.created_by_user }
-  end
-
-  def sync_candidate! candidate, result
-    block = MaterialImportBlockMatcher.match_for_sha256(candidate[:file_sha256])
-    if block
-      result.suppressed += 1
-      Rails.logger.info(
-          material_sync_log(action: 'suppressed',
-                            reason: block.reason,
-                            normalized_source_key: candidate_normalized_source_key(candidate)))
-      return
-    end
-
-    suppression = suppression_for(candidate)
-
-    if suppression
-      result.suppressed += 1
-      Rails.logger.info(
-          material_sync_log(action: 'suppressed',
-                            normalized_source_key: suppression.normalized_source_key))
-      return
-    end
-
-    import = MaterialSyncImporter.import!(candidate)
-    result.public_send("#{ import.action }=", result.public_send(import.action) + 1)
-  rescue StandardError => e
-    result.failed += 1
-    result.errors << { source_id: @source.id,
-                       normalized_source_key: candidate_normalized_source_key(candidate),
-                       error: e.message }
-    Rails.logger.warn(
-        material_sync_log(action: 'failed',
-                          error: e.message,
-                          normalized_source_key: candidate_normalized_source_key(candidate)))
-  ensure
-    close_candidate_tempfile(candidate)
-  end
-
-  def google_drive_path_candidates
-    folder_id = google_drive_folder_id
-    Enumerator.new do |entries|
-      drive_client.each_material_file_under_folder(folder_id).each do |entry|
-        entries << build_google_drive_candidate(entry)
-      end
-    end
-  end
-
-  def sync_google_drive_path! result
-    folder_id = google_drive_folder_id
-    scanned_count = 0
-
-    drive_client.each_material_file_under_folder(folder_id) do |entry|
-      scanned_count += 1
-      sync_candidate!(build_google_drive_candidate(entry), result)
-      log_google_drive_progress(folder_id, scanned_count, result) if progress_log_scan_count?(scanned_count)
-    end
-
-    log_google_drive_progress(folder_id, scanned_count, result, summary: true)
-  end
-
-  def google_drive_file_candidate
-    entry = drive_client.fetch_material_file(google_drive_file_id)
-    return nil unless entry
-
-    build_google_drive_candidate(entry, single_file: true)
-  end
-
-  def build_google_drive_candidate entry, single_file: false
-    relative_path =
-        if single_file
-          nil
-        else
-          entry[:relative_path]
-        end
-    export_path =
-        MaterialSyncExportPath.build(prefix: @source.export_path_prefix,
-                                     relative_path:,
-                                     filename: entry[:name],
-                                     source_file_id: entry[:id])
-
-    { source_kind: 'google_drive_file',
-      source_uri: entry[:web_view_link] || google_drive_file_url(entry[:id]),
-      source_path: relative_path.presence || MaterialSyncExportPath.normalize_path(entry[:name]),
-      source_file_id: entry[:id],
-      filename: entry[:name],
-      content_type: entry[:mime_type],
-      file_downloader: lambda {
-        drive_client.download_to_tempfile(entry[:id], filename: entry[:name])
-      },
-      file_sha256: entry[:sha256_checksum],
-      export_path:,
-      profile: @source.profile,
-      tag: nil,
-      url: nil,
-      created_by_user: @source.created_by_user,
-      updated_by_user: @source.updated_by_user || @source.created_by_user }
-  end
-
-  def candidate_normalized_source_key candidate
-    MaterialSyncSuppression.normalize_source_key(source_kind: candidate[:source_kind],
-                                                 source_uri: candidate[:source_uri],
-                                                 source_path: candidate[:source_path],
-                                                 source_file_id: candidate[:source_file_id])
-  end
-
-  def suppression_for candidate
-    if candidate[:source_kind] == 'google_drive_file' && candidate[:source_path].present?
-      return MaterialSyncSuppressionMatcher.match_google_drive_candidate(
-          drive_file_id: candidate[:source_file_id],
-          relative_path: candidate[:source_path])
-    end
-
-    MaterialSyncSuppressionMatcher.match(source_kind: candidate[:source_kind],
-                                         source_uri: candidate[:source_uri],
-                                         source_path: candidate[:source_path],
-                                         source_file_id: candidate[:source_file_id])
-  end
-
-  def drive_client
-    @drive_client ||= GoogleDrive::ApiClient.new
-  end
-
-  def google_drive_folder_id
-    google_drive_target_id.tap do |id|
-      if id.blank?
-        raise ArgumentError, 'google_drive_path source_file_id or source_uri is required'
-      end
-    end
-  end
-
-  def google_drive_file_id
-    google_drive_target_id.tap do |id|
-      if id.blank?
-        raise ArgumentError, 'google_drive_file source_file_id or source_uri is required'
-      end
-    end
-  end
-
-  def google_drive_target_id
-    @source.source_file_id.presence || drive_client.extract_file_id(@source.source_uri)
-  end
-
-  def google_drive_file_url file_id
-    "https://drive.google.com/file/d/#{ file_id }/view"
-  end
-
-  def close_candidate_tempfile candidate
-    tempfile = candidate[:file_tempfile]
-    return unless tempfile
-
-    tempfile.close! unless tempfile.closed?
-  rescue StandardError
-    nil
-  end
-
-  def log_result result
-    Rails.logger.info(material_sync_log(imported: result.imported,
-                                        updated: result.updated,
-                                        unchanged: result.unchanged,
-                                        suppressed: result.suppressed,
-                                        failed: result.failed))
-  end
-
-  def progress_log_scan_count? scanned_count
-    scanned_count == 1 || (scanned_count % 50).zero?
-  end
-
-  def log_google_drive_progress folder_id, scanned_count, result, summary: false
-    Rails.logger.info(
-        material_sync_log(folder_id:,
-                          scanned_count:,
-                          imported: result.imported,
-                          updated: result.updated,
-                          unchanged: result.unchanged,
-                          suppressed: result.suppressed,
-                          failed: result.failed,
-                          progress: summary ? 'summary' : 'scan'))
-  end
-
-  def material_sync_log fields
-    { material_sync_source_id: @source.id,
-      material_sync_source_name: @source.name }.merge(fields).to_json
-  end
-end

backend/app/services/material_sync_suppression_matcher.rb

@@ -1,68 +0,0 @@
-class MaterialSyncSuppressionMatcher
-  def self.match source_kind:,
-                 source_uri: nil,
-                 drive_path: nil,
-                 drive_file_id: nil,
-                 source_path: nil,
-                 source_file_id: nil
-    key = MaterialSyncSuppression.normalize_source_key(source_kind:,
-                                                       source_uri:,
-                                                       drive_path:,
-                                                       drive_file_id:,
-                                                       source_path:,
-                                                       source_file_id:)
-    return nil if key.blank?
-
-    MaterialSyncSuppression.find_by(normalized_source_key: key)
-  end
-
-  def self.match_google_drive_candidate drive_file_id:, relative_path:
-    normalized_path = validate_relative_path!(relative_path)
-
-    exact = [
-      normalize_key('google_drive_file', drive_file_id),
-      normalize_key('google_drive_path', normalized_path),
-      normalize_key('legacy_drive_path', normalized_path),
-    ].compact
-
-    suppression =
-        MaterialSyncSuppression.find_by(normalized_source_key: exact)
-    return suppression if suppression
-
-    MaterialSyncSuppression
-      .where(source_kind: ['google_drive_path_prefix', 'legacy_drive_path_prefix'])
-      .where('drive_path = :path OR :path LIKE CONCAT(drive_path, "/%")', path: normalized_path)
-      .order(:id)
-      .first
-  end
-
-  def self.suppressed?(...)
-    match(...).present?
-  end
-
-  def self.validate_relative_path! relative_path
-    raw = relative_path.to_s.delete("\0").tr('\\', '/').strip
-    raise ArgumentError, 'relative_path is required' if raw.blank?
-    raise ArgumentError, 'relative_path must be relative' if raw.start_with?('/')
-    raise ArgumentError, 'relative_path must be relative' if raw.match?(/\A[A-Za-z]:\//)
-    if raw.start_with?('My Drive/', 'マイドライブ/')
-      raise ArgumentError, 'relative_path must be relative to source folder'
-    end
-    raise ArgumentError, 'relative_path must not contain //' if raw.include?('//')
-    raise ArgumentError, 'relative_path must not end with /' if raw.end_with?('/')
-
-    parts = raw.split('/')
-    if parts.any? { |part| part.in?(['.', '..']) }
-      raise ArgumentError, 'relative_path must not contain dot segments'
-    end
-
-    raw
-  end
-
-  def self.normalize_key source_kind, value
-    return nil if value.blank?
-
-    MaterialSyncSuppression.normalize_source_key(source_kind:, source_path: value,
-                                                 source_file_id: value)
-  end
-end

backend/app/services/material_sync_suppression_registrar.rb

@@ -1,51 +0,0 @@
-class MaterialSyncSuppressionRegistrar
-  def self.create! attributes, created_by_user:
-    new(attributes, created_by_user:).create!
-  end
-
-  def initialize attributes, created_by_user:
-    @attributes = attributes
-    @created_by_user = created_by_user
-  end
-
-  def create!
-    suppression = nil
-
-    MaterialSyncSuppression.transaction do
-      suppression = MaterialSyncSuppression.create!(
-          @attributes.merge(created_by_user: @created_by_user))
-      discard_existing_materials!(suppression)
-    end
-
-    suppression
-  end
-
-  private
-
-  def discard_existing_materials! suppression
-    matching_materials(suppression).find_each do |material|
-      MaterialVersionRecorder.ensure_snapshot!(material, created_by_user: @created_by_user)
-      material.discard!
-      MaterialVersionRecorder.record!(material:,
-                                      event_type: :discard,
-                                      created_by_user: @created_by_user)
-    end
-  end
-
-  def matching_materials suppression
-    materials = Material.unscoped.kept
-
-    case suppression.source_kind
-    when 'google_drive_path', 'legacy_drive_path'
-      materials.where(source_path: suppression.drive_path)
-    when 'google_drive_path_prefix', 'legacy_drive_path_prefix'
-      path = suppression.drive_path.to_s
-      materials.where(
-          'source_path = :path OR source_path LIKE :prefix',
-          path:,
-          prefix: "#{ path }/%")
-    else
-      materials.where(normalized_source_key: suppression.normalized_source_key)
-    end
-  end
-end

backend/app/services/material_thumbnail_generator.rb

@@ -1,126 +0,0 @@
-# frozen_string_literal: true
-
-require 'mini_magick'
-require 'open3'
-require 'tempfile'
-
-
-class MaterialThumbnailGenerator
-  SIZE = '180x180'
-
-  class << self
-    def generate! material
-      new(material).generate!
-    end
-  end
-
-  def initialize material
-    @material = material
-    @ffmpeg_stderr = []
-  end
-
-  def generate!
-    return log_result(:no_file) unless @material.file.attached?
-    return log_result(:unsupported_content_type) unless image? || video?
-
-    @material.file.blob.open do |file|
-      thumbnail = image? ? image_thumbnail(file.path) : video_thumbnail(file.path)
-      return log_result(:generation_failed) unless thumbnail
-
-      return attach_thumbnail(thumbnail)
-    end
-  rescue ActiveStorage::FileNotFoundError => e
-    log_result(:file_not_found, error: e)
-  rescue MiniMagick::Error => e
-    log_result(:mini_magick_error, error: e)
-  rescue ArgumentError, StandardError => e
-    log_result(:generation_failed, error: e)
-  end
-
-  private
-
-  def image? = content_type.start_with?('image/')
-
-  def video? = content_type.start_with?('video/')
-
-  def content_type
-    return nil unless @material.file.attached?
-
-    @material.file.blob.content_type.to_s
-  end
-
-  def image_thumbnail path
-    image = MiniMagick::Image.open(path)
-    image.resize(SIZE)
-    image.format('jpg')
-    image
-  end
-
-  def video_thumbnail path
-    [1, 0].each do |seconds|
-      tempfile = Tempfile.new(['material-thumbnail', '.jpg'])
-      tempfile.close
-      ok = extract_video_frame(path, tempfile.path, seconds)
-      next unless ok && File.size?(tempfile.path)
-
-      return image_thumbnail(tempfile.path)
-    ensure
-      tempfile&.unlink
-    end
-
-    nil
-  end
-
-  def extract_video_frame input_path, output_path, seconds
-    _stdout, stderr, status =
-        Open3.capture3('ffmpeg',
-                       '-y',
-                       '-ss', seconds.to_s,
-                       '-i', input_path,
-                       '-frames:v', '1',
-                       '-f', 'image2',
-                       output_path)
-    @ffmpeg_stderr << stderr if stderr.present?
-    status.success?
-  rescue Errno::ENOENT => e
-    @ffmpeg_stderr << "ffmpeg unavailable: #{ e.message }"
-    false
-  end
-
-  def attach_thumbnail image
-    blob = nil
-    File.open(image.path) do |io|
-      blob = ActiveStorage::Blob.create_and_upload!(
-          io:,
-          filename: 'material-thumbnail.jpg',
-          content_type: 'image/jpeg')
-    end
-    @material.thumbnail.attach(blob)
-    log_result(:attached)
-  rescue StandardError => e
-    blob&.purge_later
-    log_result(:attach_failed, error: e)
-  end
-
-  def log_result result, error: nil
-    log_payload = { material_id: @material.id,
-                    file_blob_id: file_blob_id,
-                    content_type:,
-                    result:,
-                    error_class: error&.class&.name,
-                    error_message: error&.message,
-                    ffmpeg_stderr: @ffmpeg_stderr.join("\n").presence }
-    if [:attached, :no_file, :unsupported_content_type].include?(result)
-      Rails.logger.info("Material thumbnail generation: #{ log_payload.to_json }")
-    else
-      Rails.logger.warn("Material thumbnail generation: #{ log_payload.to_json }")
-    end
-    result
-  end
-
-  def file_blob_id
-    return nil unless @material.file.attached?
-
-    @material.file.blob.id
-  end
-end

backend/app/services/material_version_recorder.rb

@@ -1,73 +0,0 @@
-class MaterialVersionRecorder < VersionRecorder
-  EVENT_TYPES = ['create', 'update', 'discard', 'restore'].freeze
-
-  def self.record! material:, event_type:, created_by_user:, file_snapshot: nil
-    new(material:, event_type:, created_by_user:, file_snapshot:).record!
-  end
-
-  def initialize material:, event_type:, created_by_user:, file_snapshot: nil
-    @file_snapshot = file_snapshot
-
-    super(record: material, event_type:, created_by_user:)
-  end
-
-  def self.ensure_snapshot! material, created_by_user:
-    return if material.material_versions.exists?
-
-    record!(material:, event_type: :create,
-            created_by_user: material.created_by_user || created_by_user)
-  end
-
-  private
-
-  def version_class = MaterialVersion
-  def version_association = :material_versions
-  def record_key = :material
-
-  def snapshot_attributes
-    blob = @record.file.attached? ? @record.file.blob : nil
-    file_snapshot = build_file_snapshot(blob)
-
-    { url: @record.url,
-      parent: @record.parent,
-      tag: @record.tag,
-      tag_name: @record.tag&.name,
-      tag_category: @record.tag&.category,
-      source_kind: @record.source_kind,
-      source_uri: @record.source_uri,
-      source_path: @record.source_path,
-      source_file_id: @record.source_file_id,
-      normalized_source_key: @record.normalized_source_key,
-      export_paths_json: @record.snapshot_export_paths,
-      discarded_at: @record.discarded_at,
-      file_blob_id: file_snapshot[:file_blob_id],
-      file_filename: file_snapshot[:file_filename],
-      file_content_type: file_snapshot[:file_content_type],
-      file_byte_size: file_snapshot[:file_byte_size],
-      file_checksum: file_snapshot[:file_checksum],
-      file_sha256: file_snapshot[:file_sha256] }
-  end
-
-  def build_file_snapshot blob
-    return @file_snapshot if @file_snapshot
-    return empty_file_snapshot unless blob
-
-    { file_blob_id: blob.id,
-      file_filename: blob.filename.to_s,
-      file_content_type: blob.content_type,
-      file_byte_size: blob.byte_size,
-      file_checksum: blob.checksum,
-      file_sha256: MaterialFileSha256.metadata_sha256(blob) }
-  end
-
-  def empty_file_snapshot
-    { file_blob_id: nil,
-      file_filename: nil,
-      file_content_type: nil,
-      file_byte_size: nil,
-      file_checksum: nil,
-      file_sha256: nil }
-  end
-
-  def event_types = self.class::EVENT_TYPES
-end

backend/app/services/material_zip_exporter.rb

@@ -1,148 +0,0 @@
-require 'stringio'
-require 'zlib'
-
-# Initial implementation keeps every file payload and the final ZIP in memory.
-# Keep this service boundary stable so job/cached export paths can replace it later.
-class MaterialZipExporter
-  Entry = Struct.new(:path, :data, :mtime, keyword_init: true)
-  MissingFile = Struct.new(:material_id, :export_path, :blob_id, :filename, keyword_init: true)
-
-  class EmptyExportError < StandardError; end
-  class DuplicatePathError < StandardError; end
-  class MissingFileError < StandardError
-    attr_reader :missing_files
-
-    def initialize missing_files
-      @missing_files = missing_files
-
-      super("Missing files: #{missing_files.map(&:export_path).join(', ')}")
-    end
-  end
-
-  def initialize profile: 'legacy_drive', tag_id: nil
-    @profile = profile.presence || 'legacy_drive'
-    @tag_id = tag_id.presence
-  end
-
-  def export
-    entries = build_entries
-    raise EmptyExportError if entries.empty?
-
-    ZipWriter.write(entries)
-  end
-
-  private
-
-  def build_entries
-    rows = MaterialExportItem
-           .enabled
-           .includes(material: { file_attachment: :blob })
-           .joins(:material)
-           .merge(Material.kept)
-           .where(profile: @profile)
-           .order(:export_path)
-
-    rows = rows.where(materials: { tag_id: @tag_id }) if @tag_id
-
-    missing_files = []
-
-    entries = rows.filter_map do |item|
-      material = item.material
-      next unless material.file.attached?
-
-      data = download_blob(item, missing_files)
-      next unless data
-
-      Entry.new(path: item.export_path,
-                data:,
-                mtime: material.updated_at || Time.current)
-    end
-
-    raise MissingFileError.new(missing_files) if missing_files.any?
-
-    paths = entries.map(&:path)
-    duplicated = paths.find { |path| paths.count(path) > 1 }
-    raise DuplicatePathError, duplicated if duplicated
-
-    entries
-  end
-
-  def download_blob item, missing_files
-    blob = item.material.file.blob
-
-    blob.download
-  rescue ActiveStorage::FileNotFoundError
-    missing_files << MissingFile.new(
-        material_id: item.material_id,
-        export_path: item.export_path,
-        blob_id: blob.id,
-        filename: blob.filename.to_s,
-    )
-    nil
-  end
-
-  class ZipWriter
-    VERSION_NEEDED = 20
-    GP_FLAG = 0x0800
-    COMPRESSION_STORE = 0
-
-    def self.write entries
-      new(entries).write
-    end
-
-    def initialize entries
-      @entries = entries
-      @central_directory = []
-    end
-
-    def write
-      io = StringIO.new(''.b)
-
-      @entries.each do |entry|
-        write_entry(io, entry)
-      end
-
-      central_start = io.pos
-      @central_directory.each { |header| io.write(header) }
-      central_size = io.pos - central_start
-
-      io.write([0x06054b50, 0, 0, @entries.size, @entries.size,
-                central_size, central_start, 0].pack('VvvvvVVv'))
-      io.string
-    end
-
-    private
-
-    def write_entry io, entry
-      path = entry.path.b
-      data = entry.data.b
-      crc32 = Zlib.crc32(data)
-      dos_time, dos_date = dos_timestamp(entry.mtime)
-      offset = io.pos
-
-      local_header = [0x04034b50, VERSION_NEEDED, GP_FLAG, COMPRESSION_STORE,
-                      dos_time, dos_date, crc32, data.bytesize, data.bytesize,
-                      path.bytesize, 0].pack('VvvvvvVVVvv')
-
-      io.write(local_header)
-      io.write(path)
-      io.write(data)
-
-      @central_directory << central_header(path:, crc32:, size: data.bytesize,
-                                           dos_time:, dos_date:, offset:)
-    end
-
-    def central_header path:, crc32:, size:, dos_time:, dos_date:, offset:
-      [0x02014b50, VERSION_NEEDED, VERSION_NEEDED, GP_FLAG, COMPRESSION_STORE,
-       dos_time, dos_date, crc32, size, size, path.bytesize, 0, 0, 0, 0, 0,
-       offset].pack('VvvvvvvVVVvvvvvVV') + path
-    end
-
-    def dos_timestamp time
-      local = time.to_time
-      dos_time = (local.hour << 11) | (local.min << 5) | (local.sec / 2)
-      dos_date = ((local.year - 1980) << 9) | (local.month << 5) | local.day
-      [dos_time, dos_date]
-    end
-  end
-end

backend/app/services/post_version_recorder.rb

@@ -23,7 +23,6 @@ class PostVersionRecorder < VersionRecorder
     { title: @record.title,
       url: @record.url,
       thumbnail_base: @record.thumbnail_base,
-      video_ms: @record.video_ms,
       tags: @record.snapshot_tag_names.join(' '),
       parent_post_ids: @record.snapshot_parent_post_ids.join(' '),
       original_created_from: @record.original_created_from,

backend/app/services/similarity/calc.rb

@@ -1,6 +1,6 @@
 module Similarity
   class Calc
-    def self.call model, tgt, scope: nil
+    def self.call model, tgt
       similarity_model = "#{ model.name }Similarity".constantize
 
       # 最大保存件数
@@ -8,8 +8,7 @@ module Similarity
 
       similarity_model.delete_all
 
-      scope ||= model.all
-      posts = scope.includes(tgt).select(:id).to_a
+      posts = model.includes(tgt).select(:id).to_a
 
       tag_ids = { }
       tag_cnts = { }

backend/app/services/tag_version_recorder.rb

@@ -16,7 +16,6 @@ class TagVersionRecorder < VersionRecorder
   def snapshot_attributes
     { name: @record.name,
       category: @record.category,
-      deprecated_at: @record.deprecated_at,
       aliases: @record.snapshot_aliases.join(' '),
       parent_tag_ids: @record.snapshot_parent_tag_ids.join(' ') }
   end

backend/app/services/version_recorder.rb

@@ -73,7 +73,7 @@ class VersionRecorder
   end
 
   def validate_event_type!
-    return if event_types.include?(@event_type)
+    return if EVENT_TYPES.include?(@event_type)
 
     raise ArgumentError, "Invalid event_type: #{ @event_type }"
   end
@@ -84,5 +84,4 @@ class VersionRecorder
   def snapshot_attributes = raise NotImplementedError
 
   def record_class = @record.class
-  def event_types = self.class::EVENT_TYPES
 end

backend/config/routes.rb

@@ -63,29 +63,6 @@ Rails.application.routes.draw do
     end
   end
 
-  namespace :gekanator do
-    resources :games, only: [:create], controller: '/gekanator_games' do
-      member do
-        get :extra_questions
-        post :extra_question_answers
-      end
-    end
-    resources :posts, only: [:index], controller: '/gekanator_posts'
-    resources :questions, only: [:index], controller: '/gekanator_questions'
-    resources :question_suggestions,
-              only: [:create],
-              controller: '/gekanator_question_suggestions' do
-      member do
-        post :ai_convert
-      end
-    end
-  end
-
-  get 'users/settings', to: 'user_settings#show'
-  patch 'users/settings', to: 'user_settings#update'
-  get 'users/theme_slots', to: 'user_theme_slots#index'
-  put 'users/theme_slots/:base_theme/:slot_no', to: 'user_theme_slots#update'
-
   resources :users, only: [:create, :update] do
     collection do
       post :verify
@@ -118,8 +95,5 @@ Rails.application.routes.draw do
     resources :skip_events, controller: :theatre_skip_events, only: [:index]
   end
 
-  get 'materials/download.zip', to: 'materials#download'
-  get 'materials/versions', to: 'material_versions#index'
-  resources :material_sync_suppressions, path: 'materials/suppressions', only: [:index, :create]
   resources :materials, only: [:index, :show, :create, :update, :destroy]
 end

backend/db/migrate/20260519013100_add_video_ms_to_posts.rb

@@ -1,9 +0,0 @@
-class AddVideoMsToPosts < ActiveRecord::Migration[8.0]
-  def change
-    add_column :posts, :video_ms, :integer
-    add_index :posts, [:video_ms, :id], name: 'idx_posts_video_ms_id'
-
-    add_check_constraint :posts, 'video_ms IS NULL OR video_ms > 0',
-                         name: 'chk_posts_video_ms_positive'
-  end
-end

backend/db/migrate/20260607000000_create_gekanator_games.rb

@@ -1,18 +0,0 @@
-class CreateGekanatorGames < ActiveRecord::Migration[8.0]
-  def change
-    create_table :gekanator_games do |t|
-      t.references :user, null: false, foreign_key: true
-      t.references :guessed_post, null: false, foreign_key: { to_table: :posts }
-      t.references :correct_post, null: false, foreign_key: { to_table: :posts }
-      t.boolean :won, null: false
-      t.integer :question_count, null: false
-      t.json :answers, null: false
-
-      t.timestamps
-    end
-
-    add_check_constraint :gekanator_games,
-                         'question_count >= 0',
-                         name: 'chk_gekanator_games_question_count_nonnegative'
-  end
-end

backend/db/migrate/20260608000000_create_gekanator_question_suggestions.rb

@@ -1,14 +0,0 @@
-class CreateGekanatorQuestionSuggestions < ActiveRecord::Migration[8.0]
-  def change
-    create_table :gekanator_question_suggestions do |t|
-      t.references :gekanator_game,
-                   null: false,
-                   foreign_key: { on_delete: :cascade }
-      t.references :user, null: false, foreign_key: true
-      t.text :question_text, null: false
-      t.boolean :processed, null: false, default: false
-
-      t.timestamps
-    end
-  end
-end

backend/db/migrate/20260608002000_add_answer_to_gekanator_question_suggestions.rb

@@ -1,5 +0,0 @@
-class AddAnswerToGekanatorQuestionSuggestions < ActiveRecord::Migration[8.0]
-  def change
-    add_column :gekanator_question_suggestions, :answer, :string, null: false
-  end
-end

backend/db/migrate/20260609000000_create_gekanator_questions.rb

@@ -1,19 +0,0 @@
-class CreateGekanatorQuestions < ActiveRecord::Migration[8.0]
-  def change
-    create_table :gekanator_questions do |t|
-      t.string :text, null: false
-      t.string :kind, null: false
-      t.json :condition, null: false
-      t.string :source, null: false, default: 'ai_generated'
-      t.string :status, null: false, default: 'pending'
-      t.float :priority_weight, null: false, default: 1.0
-      t.references :gekanator_question_suggestion,
-                   null: true,
-                   foreign_key: true
-      t.references :created_by,
-                   null: true,
-                   foreign_key: { to_table: :users }
-      t.timestamps
-    end
-  end
-end

backend/db/migrate/20260609001000_create_gekanator_ai_runs.rb

@@ -1,13 +0,0 @@
-class CreateGekanatorAiRuns < ActiveRecord::Migration[8.0]
-  def change
-    create_table :gekanator_ai_runs do |t|
-      t.string :model, null: false
-      t.integer :input_tokens, null: false, default: 0
-      t.integer :output_tokens, null: false, default: 0
-      t.decimal :estimated_cost_jpy, precision: 8, scale: 3, null: false, default: 0
-      t.string :status, null: false, default: 'pending'
-      t.references :gekanator_question_suggestion, null: false, foreign_key: true
-      t.timestamps
-    end
-  end
-end

backend/db/migrate/20260610000000_create_gekanator_question_examples.rb

@@ -1,19 +0,0 @@
-class CreateGekanatorQuestionExamples < ActiveRecord::Migration[8.0]
-  def change
-    create_table :gekanator_question_examples do |t|
-      t.references :gekanator_question, null: false, foreign_key: true
-      t.references :post, null: false, foreign_key: true
-      t.references :user, null: false, foreign_key: true
-      t.references :gekanator_game, null: true, foreign_key: true
-      t.string :answer, null: false
-      t.string :source, null: false, default: 'post_game_extra'
-      t.float :weight, null: false, default: 1.0
-      t.timestamps
-    end
-
-    add_index :gekanator_question_examples,
-              [:gekanator_question_id, :post_id, :user_id],
-              unique: true,
-              name: 'idx_gekanator_question_examples_on_question_post_user'
-  end
-end

backend/db/migrate/20260612000000_add_answer_statistics_to_gekanator_question_examples.rb

@@ -1,40 +0,0 @@
-class AddAnswerStatisticsToGekanatorQuestionExamples < ActiveRecord::Migration[8.0]
-  class MigrationGekanatorQuestionExample < ApplicationRecord
-    self.table_name = 'gekanator_question_examples'
-  end
-
-  def up
-    add_column :gekanator_question_examples,
-               :answer_counts,
-               :json,
-               null: true
-    add_column :gekanator_question_examples,
-               :sample_count,
-               :integer,
-               null: false,
-               default: 1
-
-    MigrationGekanatorQuestionExample.reset_column_information
-    MigrationGekanatorQuestionExample.find_each do |example|
-      counts = {
-        'yes' => 0,
-        'no' => 0,
-        'partial' => 0,
-        'probably_no' => 0,
-        'unknown' => 0
-      }
-      counts[example.answer] = 1 if counts.key?(example.answer)
-
-      example.update_columns(
-        answer_counts: counts,
-        sample_count: 1)
-    end
-
-    change_column_null :gekanator_question_examples, :answer_counts, false
-  end
-
-  def down
-    remove_column :gekanator_question_examples, :sample_count
-    remove_column :gekanator_question_examples, :answer_counts
-  end
-end

backend/db/migrate/20260621000000_add_deprecated_at_to_tags.rb

@@ -1,20 +0,0 @@
-class AddDeprecatedAtToTags < ActiveRecord::Migration[8.0]
-  def up
-    add_column :tags, :deprecated_at, :datetime, after: :category
-    add_column :tag_versions, :deprecated_at, :datetime, after: :parent_tag_ids
-
-    add_index :tags, :deprecated_at
-
-    add_check_constraint :tags, "deprecated_at IS NULL OR category <> 'nico'",
-                         name: 'chk_tags_deprecated_at_not_nico'
-  end
-
-  def down
-    remove_check_constraint :tags, name: 'chk_tags_deprecated_at_not_nico'
-
-    remove_index :tags, :deprecated_at
-
-    remove_column :tag_versions, :deprecated_at, :datetime
-    remove_column :tags, :deprecated_at
-  end
-end

backend/db/migrate/20260622010000_create_post_tag_sections.rb

@@ -1,19 +0,0 @@
-class CreatePostTagSections < ActiveRecord::Migration[8.0]
-  def change
-    create_table :post_tag_sections, primary_key: [:post_id, :tag_id, :begin_ms] do |t|
-      t.references :post, null: false, foreign_key: true, index: false
-      t.references :tag, null: false, foreign_key: true, index: false
-      t.integer :begin_ms, null: false
-      t.integer :end_ms, null: true
-      t.timestamps
-
-      t.index [:post_id, :begin_ms], name: 'idx_post_tag_sections_post_id_begin_ms'
-
-      t.check_constraint 'begin_ms >= 0',
-                         name: 'chk_post_tag_sections_begin_ms_natural'
-
-      t.check_constraint 'end_ms IS NULL OR begin_ms < end_ms',
-                         name: 'chk_post_tag_sections_end_ms_after_begin_ms'
-    end
-  end
-end

backend/db/migrate/20260622020000_add_video_ms_to_post_versions.rb

@@ -1,9 +0,0 @@
-class AddVideoMsToPostVersions < ActiveRecord::Migration[8.0]
-  def change
-    add_column :post_versions, :video_ms, :integer
-    add_index :post_versions, [:video_ms, :post_id], name: 'idx_post_versions_video_ms_post_id'
-
-    add_check_constraint :post_versions, 'video_ms IS NULL OR video_ms > 0',
-                         name: 'chk_post_versions_video_ms_positive'
-  end
-end

backend/db/migrate/20260623000000_enhance_material_management.rb

@@ -1,88 +0,0 @@
-class EnhanceMaterialManagement < ActiveRecord::Migration[8.0]
-  def up
-    change_table :materials, bulk: true do |t|
-      t.integer :version_no, null: false, default: 1
-    end
-
-    change_table :material_versions, bulk: true do |t|
-      t.string :event_type
-      t.string :tag_name
-      t.string :tag_category
-      t.json :export_paths_json
-      t.bigint :file_blob_id
-      t.string :file_filename
-      t.string :file_content_type
-      t.bigint :file_byte_size
-      t.string :file_checksum
-      t.string :file_sha256
-    end
-
-    execute <<~SQL.squish
-      UPDATE material_versions
-      SET event_type = CASE
-                       WHEN version_no = 1 THEN 'create'
-                       ELSE 'update'
-                       END
-      WHERE event_type IS NULL
-    SQL
-
-    change_column_null :material_versions, :event_type, false
-    add_index :material_versions, :file_blob_id
-
-    add_check_constraint :material_versions,
-                         "event_type IN ('create', 'update', 'discard', 'restore')",
-                         name: 'material_versions_event_type_valid'
-
-    create_table :material_export_items do |t|
-      t.references :material, null: false, foreign_key: true
-      t.string :profile, null: false, default: 'legacy_drive'
-      t.string :export_path, null: false
-      t.boolean :enabled, null: false, default: true
-      t.references :created_by_user, foreign_key: { to_table: :users }
-      t.timestamps
-
-      t.index [:profile, :export_path], unique: true
-      t.index [:material_id, :profile], unique: true
-    end
-
-    create_table :material_import_blocks do |t|
-      t.string :match_kind, null: false
-      t.string :sha256
-      t.string :external_path_pattern
-      t.string :reason, null: false
-      t.text :note
-      t.references :created_by_user, foreign_key: { to_table: :users }
-      t.timestamps
-    end
-
-    execute <<~SQL.squish
-      UPDATE materials
-      SET version_no = COALESCE(
-        (SELECT MAX(material_versions.version_no)
-         FROM material_versions
-         WHERE material_versions.material_id = materials.id),
-        1)
-    SQL
-  end
-
-  def down
-    drop_table :material_import_blocks
-    drop_table :material_export_items
-
-    remove_check_constraint :material_versions, name: 'material_versions_event_type_valid'
-
-    remove_index :material_versions, :file_blob_id
-    remove_column :material_versions, :event_type
-    remove_column :material_versions, :tag_name
-    remove_column :material_versions, :tag_category
-    remove_column :material_versions, :export_paths_json
-    remove_column :material_versions, :file_blob_id
-    remove_column :material_versions, :file_filename
-    remove_column :material_versions, :file_content_type
-    remove_column :material_versions, :file_byte_size
-    remove_column :material_versions, :file_checksum
-    remove_column :material_versions, :file_sha256
-
-    remove_column :materials, :version_no
-  end
-end

backend/db/migrate/20260625000000_reconcile_material_sync_suppressions.rb

@@ -1,118 +0,0 @@
-class ReconcileMaterialSyncSuppressions < ActiveRecord::Migration[8.0]
-  MATERIAL_VERSION_EVENT_CONSTRAINT = 'material_versions_event_type_valid'
-
-  def up
-    ensure_material_sync_suppressions!
-    ensure_material_source_columns!
-    ensure_material_active_source_key!
-    remove_material_file_suppression!
-    remove_material_version_file_suppression!
-    reconcile_material_version_event_constraint!
-  end
-
-  def down
-    raise ActiveRecord::IrreversibleMigration
-  end
-
-  private
-
-  def ensure_material_sync_suppressions!
-    return if table_exists?(:material_sync_suppressions)
-
-    create_table :material_sync_suppressions do |t|
-      t.string :source_kind, null: false
-      t.string :source_uri
-      t.string :drive_path
-      t.string :drive_file_id
-      t.string :normalized_source_key, null: false
-      t.string :reason, null: false
-      t.references :created_by_user, foreign_key: { to_table: :users }
-      t.timestamps
-
-      t.index :normalized_source_key, unique: true
-      t.index :source_kind
-      t.index :drive_file_id
-    end
-  end
-
-  def ensure_material_source_columns!
-    add_column :materials, :source_kind, :string unless column_exists?(:materials, :source_kind)
-    add_column :materials, :source_uri, :string unless column_exists?(:materials, :source_uri)
-    add_column :materials, :source_path, :string unless column_exists?(:materials, :source_path)
-    unless column_exists?(:materials, :source_file_id)
-      add_column :materials, :source_file_id, :string
-    end
-    unless column_exists?(:materials, :normalized_source_key)
-      add_column :materials, :normalized_source_key, :string
-    end
-
-    if index_exists?(:materials, :normalized_source_key)
-      remove_index :materials, column: :normalized_source_key
-    end
-  end
-
-  def ensure_material_active_source_key!
-    unless column_exists?(:materials, :active_normalized_source_key)
-      change_table :materials do |t|
-        t.virtual :active_normalized_source_key,
-                  type: :string,
-                  as: 'IF(discarded_at IS NULL, normalized_source_key, NULL)',
-                  stored: false
-      end
-    end
-
-    return if index_exists?(:materials,
-                            :active_normalized_source_key,
-                            name: 'index_materials_on_active_normalized_source_key')
-
-    add_index :materials,
-              :active_normalized_source_key,
-              unique: true,
-              name: 'index_materials_on_active_normalized_source_key'
-  end
-
-  def remove_material_file_suppression!
-    if foreign_key_exists?(:materials, :users, column: :file_suppressed_by_user_id)
-      remove_foreign_key :materials, column: :file_suppressed_by_user_id
-    end
-
-    if index_exists?(:materials,
-                    :file_suppressed_by_user_id,
-                    name: 'index_materials_on_file_suppressed_by_user_id')
-      remove_index :materials, name: 'index_materials_on_file_suppressed_by_user_id'
-    end
-
-    remove_column :materials, :file_suppressed_at if column_exists?(
-        :materials,
-        :file_suppressed_at)
-    remove_column :materials, :file_suppressed_by_user_id if column_exists?(
-        :materials,
-        :file_suppressed_by_user_id)
-    remove_column :materials, :file_suppression_reason if column_exists?(
-        :materials,
-        :file_suppression_reason)
-  end
-
-  def remove_material_version_file_suppression!
-    remove_column :material_versions, :file_suppressed_at if column_exists?(
-        :material_versions,
-        :file_suppressed_at)
-    remove_column :material_versions, :file_suppression_reason if column_exists?(
-        :material_versions,
-        :file_suppression_reason)
-  end
-
-  def reconcile_material_version_event_constraint!
-    constraint = check_constraints(:material_versions).find do |candidate|
-      candidate.name == MATERIAL_VERSION_EVENT_CONSTRAINT
-    end
-    return if constraint && !constraint.expression.include?('suppress')
-
-    if constraint
-      remove_check_constraint :material_versions, name: MATERIAL_VERSION_EVENT_CONSTRAINT
-    end
-    add_check_constraint :material_versions,
-                         "event_type IN ('create', 'update', 'discard', 'restore')",
-                         name: MATERIAL_VERSION_EVENT_CONSTRAINT
-  end
-end

backend/db/migrate/20260625010000_create_material_sync_sources.rb

@@ -1,22 +0,0 @@
-class CreateMaterialSyncSources < ActiveRecord::Migration[8.0]
-  def change
-    create_table :material_sync_sources do |t|
-      t.string :name, null: false
-      t.string :source_kind, null: false
-      t.string :source_uri
-      t.string :source_path
-      t.string :source_file_id
-      t.string :profile, null: false, default: 'legacy_drive'
-      t.boolean :enabled, null: false, default: true
-      t.string :default_tag_name
-      t.string :export_path_prefix
-      t.datetime :last_synced_at
-      t.references :created_by_user, foreign_key: { to_table: :users }
-      t.references :updated_by_user, foreign_key: { to_table: :users }
-      t.timestamps
-
-      t.index :enabled
-      t.index :source_kind
-    end
-  end
-end

backend/db/migrate/20260626000000_add_source_snapshot_to_material_versions.rb

@@ -1,19 +0,0 @@
-class AddSourceSnapshotToMaterialVersions < ActiveRecord::Migration[8.0]
-  def change
-    unless column_exists?(:material_versions, :source_kind)
-      add_column :material_versions, :source_kind, :string
-    end
-    unless column_exists?(:material_versions, :source_uri)
-      add_column :material_versions, :source_uri, :string
-    end
-    unless column_exists?(:material_versions, :source_path)
-      add_column :material_versions, :source_path, :string
-    end
-    unless column_exists?(:material_versions, :source_file_id)
-      add_column :material_versions, :source_file_id, :string
-    end
-    unless column_exists?(:material_versions, :normalized_source_key)
-      add_column :material_versions, :normalized_source_key, :string
-    end
-  end
-end

backend/db/migrate/20260626010000_backfill_initial_material_versions.rb

@@ -1,171 +0,0 @@
-require 'json'
-
-class BackfillInitialMaterialVersions < ActiveRecord::Migration[8.0]
-  class MigrationMaterial < ActiveRecord::Base
-    self.table_name = 'materials'
-  end
-
-  class MigrationMaterialExportItem < ActiveRecord::Base
-    self.table_name = 'material_export_items'
-  end
-
-  class MigrationMaterialVersion < ActiveRecord::Base
-    self.table_name = 'material_versions'
-  end
-
-  class MigrationStorageAttachment < ActiveRecord::Base
-    self.table_name = 'active_storage_attachments'
-  end
-
-  class MigrationStorageBlob < ActiveRecord::Base
-    self.table_name = 'active_storage_blobs'
-  end
-
-  class MigrationTag < ActiveRecord::Base
-    self.table_name = 'tags'
-  end
-
-  class MigrationTagName < ActiveRecord::Base
-    self.table_name = 'tag_names'
-  end
-
-  def up
-    say_with_time 'Backfilling initial material versions' do
-      materials_without_versions.find_in_batches(batch_size: 500) do |materials|
-        material_ids = materials.map(&:id)
-        tags_by_id = load_tags(materials.map(&:tag_id).compact.uniq)
-        export_paths_by_material_id = load_export_paths(material_ids)
-        file_snapshots_by_material_id = load_file_snapshots(material_ids)
-
-        rows = materials.map do |material|
-          tag = tags_by_id[material.tag_id]
-          file_snapshot = file_snapshots_by_material_id[material.id] || empty_file_snapshot
-
-          { material_id: material.id,
-            version_no: 1,
-            event_type: 'create',
-            url: material.url,
-            parent_id: material.parent_id,
-            tag_id: material.tag_id,
-            tag_name: tag&.fetch(:name, nil),
-            tag_category: tag&.fetch(:category, nil),
-            source_kind: material.source_kind,
-            source_uri: material.source_uri,
-            source_path: material.source_path,
-            source_file_id: material.source_file_id,
-            normalized_source_key: material.normalized_source_key,
-            export_paths_json: export_paths_by_material_id[material.id] || { },
-            discarded_at: material.discarded_at,
-            file_blob_id: file_snapshot[:file_blob_id],
-            file_filename: file_snapshot[:file_filename],
-            file_content_type: file_snapshot[:file_content_type],
-            file_byte_size: file_snapshot[:file_byte_size],
-            file_checksum: file_snapshot[:file_checksum],
-            file_sha256: file_snapshot[:file_sha256],
-            created_by_user_id: material.created_by_user_id,
-            updated_by_user_id: material.updated_by_user_id,
-            created_at: material.created_at,
-            updated_at: material.created_at }
-        end
-
-        MigrationMaterialVersion.insert_all!(rows) if rows.present?
-      end
-    end
-
-    execute <<~SQL.squish
-      UPDATE materials
-      SET version_no = COALESCE(
-        (
-          SELECT MAX(material_versions.version_no)
-          FROM material_versions
-          WHERE material_versions.material_id = materials.id
-        ),
-        1
-      )
-    SQL
-  end
-
-  def down
-    raise ActiveRecord::IrreversibleMigration
-  end
-
-  private
-
-  def materials_without_versions
-    MigrationMaterial.where.not(id: MigrationMaterialVersion.select(:material_id))
-  end
-
-  def load_tags tag_ids
-    return { } if tag_ids.empty?
-
-    tag_name_ids_by_tag_id = MigrationTag.where(id: tag_ids).pluck(:id, :tag_name_id).to_h
-    tag_names_by_id =
-        MigrationTagName
-        .where(id: tag_name_ids_by_tag_id.values.uniq)
-        .pluck(:id, :name)
-        .to_h
-    categories_by_tag_id = MigrationTag.where(id: tag_ids).pluck(:id, :category).to_h
-
-    tag_ids.each_with_object({ }) do |tag_id, hash|
-      hash[tag_id] = { name: tag_names_by_id[tag_name_ids_by_tag_id[tag_id]],
-                       category: categories_by_tag_id[tag_id] }
-    end
-  end
-
-  def load_export_paths material_ids
-    MigrationMaterialExportItem
-      .where(material_id: material_ids)
-      .order(:material_id, :profile)
-      .pluck(:material_id, :profile, :export_path)
-      .each_with_object({ }) do |(material_id, profile, export_path), hash|
-        hash[material_id] ||= { }
-        hash[material_id][profile] = export_path
-      end
-  end
-
-  def load_file_snapshots material_ids
-    attachments_by_material_id =
-        MigrationStorageAttachment
-        .where(record_type: 'Material', name: 'file', record_id: material_ids)
-        .pluck(:record_id, :blob_id)
-        .to_h
-
-    blobs_by_id =
-        MigrationStorageBlob
-        .where(id: attachments_by_material_id.values.uniq)
-        .index_by(&:id)
-
-    attachments_by_material_id.each_with_object({ }) do |(material_id, blob_id), hash|
-      blob = blobs_by_id[blob_id]
-      next unless blob
-
-      hash[material_id] = {
-        file_blob_id: blob.id,
-        file_filename: blob.filename.to_s,
-        file_content_type: blob.content_type,
-        file_byte_size: blob.byte_size,
-        file_checksum: blob.checksum,
-        file_sha256: blob_metadata(blob)['sha256']
-      }
-    end
-  end
-
-  def empty_file_snapshot
-    { file_blob_id: nil,
-      file_filename: nil,
-      file_content_type: nil,
-      file_byte_size: nil,
-      file_checksum: nil,
-      file_sha256: nil }
-  end
-
-  def blob_metadata blob
-    metadata = blob.metadata
-    return metadata if metadata.is_a?(Hash)
-    return { } if metadata.blank?
-
-    JSON.parse(metadata)
-  rescue JSON::ParserError
-    { }
-  end
-end

backend/db/migrate/20260704000000_rebuild_settings_as_typed_user_settings.rb

@@ -1,31 +0,0 @@
-class RebuildSettingsAsTypedUserSettings < ActiveRecord::Migration[8.0]
-  def change
-    remove_foreign_key :settings, :users if foreign_key_exists?(:settings, :users)
-    remove_index :settings, :user_id if index_exists?(:settings, :user_id)
-
-    remove_column :settings, :key, :string if column_exists?(:settings, :key)
-    remove_column :settings, :value, :json if column_exists?(:settings, :value)
-
-    change_column_null :settings, :user_id, false
-
-    add_column :settings, :theme, :string, null: false, default: 'system'
-    add_column :settings,
-               :auto_fetch_title,
-               :string,
-               null: false,
-               default: 'manual'
-    add_column :settings,
-               :auto_fetch_thumbnail,
-               :string,
-               null: false,
-               default: 'manual'
-    add_column :settings,
-               :wiki_editor_mode,
-               :string,
-               null: false,
-               default: 'split'
-
-    add_index :settings, :user_id, unique: true
-    add_foreign_key :settings, :users
-  end
-end

backend/db/migrate/20260705000000_create_user_theme_slots.rb

@@ -1,22 +0,0 @@
-class CreateUserThemeSlots < ActiveRecord::Migration[8.0]
-  def change
-    create_table :user_theme_slots do |t|
-      t.references :user, null: false, foreign_key: true
-      t.string :base_theme, null: false
-      t.integer :slot_no, null: false
-      t.json :tokens, null: false
-      t.timestamps
-    end
-
-    add_index :user_theme_slots,
-              [:user_id, :base_theme, :slot_no],
-              unique: true,
-              name: 'index_user_theme_slots_on_user_theme_and_slot'
-    add_check_constraint :user_theme_slots,
-                         "base_theme IN ('light', 'dark')",
-                         name: 'user_theme_slots_base_theme_valid'
-    add_check_constraint :user_theme_slots,
-                         'slot_no BETWEEN 1 AND 3',
-                         name: 'user_theme_slots_slot_no_valid'
-  end
-end

backend/db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[8.0].define(version: 2026_07_05_000000) do
+ActiveRecord::Schema[8.0].define(version: 2026_06_06_000000) do
   create_table "active_storage_attachments", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.string "name", null: false
     t.string "record_type", null: false
@@ -48,79 +48,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_07_05_000000) do
     t.index ["tag_id"], name: "index_deerjikists_on_tag_id"
   end
 
-  create_table "gekanator_ai_runs", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.string "model", null: false
-    t.integer "input_tokens", default: 0, null: false
-    t.integer "output_tokens", default: 0, null: false
-    t.decimal "estimated_cost_jpy", precision: 8, scale: 3, default: "0.0", null: false
-    t.string "status", default: "pending", null: false
-    t.bigint "gekanator_question_suggestion_id", null: false
-    t.datetime "created_at", null: false
-    t.datetime "updated_at", null: false
-    t.index ["gekanator_question_suggestion_id"], name: "index_gekanator_ai_runs_on_gekanator_question_suggestion_id"
-  end
-
-  create_table "gekanator_games", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.bigint "user_id", null: false
-    t.bigint "guessed_post_id", null: false
-    t.bigint "correct_post_id", null: false
-    t.boolean "won", null: false
-    t.integer "question_count", null: false
-    t.json "answers", null: false
-    t.datetime "created_at", null: false
-    t.datetime "updated_at", null: false
-    t.index ["correct_post_id"], name: "index_gekanator_games_on_correct_post_id"
-    t.index ["guessed_post_id"], name: "index_gekanator_games_on_guessed_post_id"
-    t.index ["user_id"], name: "index_gekanator_games_on_user_id"
-    t.check_constraint "`question_count` >= 0", name: "chk_gekanator_games_question_count_nonnegative"
-  end
-
-  create_table "gekanator_question_examples", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.bigint "gekanator_question_id", null: false
-    t.bigint "post_id", null: false
-    t.bigint "user_id", null: false
-    t.bigint "gekanator_game_id"
-    t.string "answer", null: false
-    t.string "source", default: "post_game_extra", null: false
-    t.float "weight", default: 1.0, null: false
-    t.datetime "created_at", null: false
-    t.datetime "updated_at", null: false
-    t.json "answer_counts", null: false
-    t.integer "sample_count", default: 1, null: false
-    t.index ["gekanator_game_id"], name: "index_gekanator_question_examples_on_gekanator_game_id"
-    t.index ["gekanator_question_id", "post_id", "user_id"], name: "idx_gekanator_question_examples_on_question_post_user", unique: true
-    t.index ["gekanator_question_id"], name: "index_gekanator_question_examples_on_gekanator_question_id"
-    t.index ["post_id"], name: "index_gekanator_question_examples_on_post_id"
-    t.index ["user_id"], name: "index_gekanator_question_examples_on_user_id"
-  end
-
-  create_table "gekanator_question_suggestions", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.bigint "gekanator_game_id", null: false
-    t.bigint "user_id", null: false
-    t.text "question_text", null: false
-    t.boolean "processed", default: false, null: false
-    t.datetime "created_at", null: false
-    t.datetime "updated_at", null: false
-    t.string "answer", null: false
-    t.index ["gekanator_game_id"], name: "index_gekanator_question_suggestions_on_gekanator_game_id"
-    t.index ["user_id"], name: "index_gekanator_question_suggestions_on_user_id"
-  end
-
-  create_table "gekanator_questions", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.string "text", null: false
-    t.string "kind", null: false
-    t.json "condition", null: false
-    t.string "source", default: "ai_generated", null: false
-    t.string "status", default: "pending", null: false
-    t.float "priority_weight", default: 1.0, null: false
-    t.bigint "gekanator_question_suggestion_id"
-    t.bigint "created_by_id"
-    t.datetime "created_at", null: false
-    t.datetime "updated_at", null: false
-    t.index ["created_by_id"], name: "index_gekanator_questions_on_created_by_id"
-    t.index ["gekanator_question_suggestion_id"], name: "index_gekanator_questions_on_gekanator_question_suggestion_id"
-  end
-
   create_table "ip_addresses", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.binary "ip_address", limit: 16, null: false
     t.datetime "banned_at"
@@ -130,69 +57,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_07_05_000000) do
     t.index ["ip_address"], name: "index_ip_addresses_on_ip_address", unique: true
   end
 
-  create_table "material_export_items", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.bigint "material_id", null: false
-    t.string "profile", default: "legacy_drive", null: false
-    t.string "export_path", null: false
-    t.boolean "enabled", default: true, null: false
-    t.bigint "created_by_user_id"
-    t.datetime "created_at", null: false
-    t.datetime "updated_at", null: false
-    t.index ["created_by_user_id"], name: "index_material_export_items_on_created_by_user_id"
-    t.index ["material_id", "profile"], name: "index_material_export_items_on_material_id_and_profile", unique: true
-    t.index ["material_id"], name: "index_material_export_items_on_material_id"
-    t.index ["profile", "export_path"], name: "index_material_export_items_on_profile_and_export_path", unique: true
-  end
-
-  create_table "material_import_blocks", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.string "match_kind", null: false
-    t.string "sha256"
-    t.string "external_path_pattern"
-    t.string "reason", null: false
-    t.text "note"
-    t.bigint "created_by_user_id"
-    t.datetime "created_at", null: false
-    t.datetime "updated_at", null: false
-    t.index ["created_by_user_id"], name: "index_material_import_blocks_on_created_by_user_id"
-  end
-
-  create_table "material_sync_sources", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.string "name", null: false
-    t.string "source_kind", null: false
-    t.string "source_uri"
-    t.string "source_path"
-    t.string "source_file_id"
-    t.string "profile", default: "legacy_drive", null: false
-    t.boolean "enabled", default: true, null: false
-    t.string "default_tag_name"
-    t.string "export_path_prefix"
-    t.datetime "last_synced_at"
-    t.bigint "created_by_user_id"
-    t.bigint "updated_by_user_id"
-    t.datetime "created_at", null: false
-    t.datetime "updated_at", null: false
-    t.index ["created_by_user_id"], name: "index_material_sync_sources_on_created_by_user_id"
-    t.index ["enabled"], name: "index_material_sync_sources_on_enabled"
-    t.index ["source_kind"], name: "index_material_sync_sources_on_source_kind"
-    t.index ["updated_by_user_id"], name: "index_material_sync_sources_on_updated_by_user_id"
-  end
-
-  create_table "material_sync_suppressions", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.string "source_kind", null: false
-    t.string "source_uri"
-    t.string "drive_path"
-    t.string "drive_file_id"
-    t.string "normalized_source_key", null: false
-    t.string "reason", null: false
-    t.bigint "created_by_user_id"
-    t.datetime "created_at", null: false
-    t.datetime "updated_at", null: false
-    t.index ["created_by_user_id"], name: "index_material_sync_suppressions_on_created_by_user_id"
-    t.index ["drive_file_id"], name: "index_material_sync_suppressions_on_drive_file_id"
-    t.index ["normalized_source_key"], name: "index_material_sync_suppressions_on_normalized_source_key", unique: true
-    t.index ["source_kind"], name: "index_material_sync_suppressions_on_source_kind"
-  end
-
   create_table "material_versions", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.bigint "material_id", null: false
     t.integer "version_no", null: false
@@ -204,31 +68,14 @@ ActiveRecord::Schema[8.0].define(version: 2026_07_05_000000) do
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
     t.datetime "discarded_at"
-    t.string "event_type", null: false
-    t.string "tag_name"
-    t.string "tag_category"
-    t.json "export_paths_json"
-    t.bigint "file_blob_id"
-    t.string "file_filename"
-    t.string "file_content_type"
-    t.bigint "file_byte_size"
-    t.string "file_checksum"
-    t.string "file_sha256"
-    t.string "source_kind"
-    t.string "source_uri"
-    t.string "source_path"
-    t.string "source_file_id"
-    t.string "normalized_source_key"
     t.index ["created_by_user_id"], name: "index_material_versions_on_created_by_user_id"
     t.index ["discarded_at"], name: "index_material_versions_on_discarded_at"
-    t.index ["file_blob_id"], name: "index_material_versions_on_file_blob_id"
     t.index ["material_id", "version_no"], name: "index_material_versions_on_material_id_and_version_no", unique: true
     t.index ["material_id"], name: "index_material_versions_on_material_id"
     t.index ["parent_id"], name: "index_material_versions_on_parent_id"
     t.index ["tag_id"], name: "index_material_versions_on_tag_id"
     t.index ["updated_by_user_id"], name: "index_material_versions_on_updated_by_user_id"
     t.index ["url"], name: "index_material_versions_on_url"
-    t.check_constraint "`event_type` in (_utf8mb4'create',_utf8mb4'update',_utf8mb4'discard',_utf8mb4'restore')", name: "material_versions_event_type_valid"
   end
 
   create_table "materials", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
@@ -241,14 +88,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_07_05_000000) do
     t.datetime "updated_at", null: false
     t.datetime "discarded_at"
     t.virtual "active_url", type: :string, as: "if((`discarded_at` is null),`url`,NULL)"
-    t.integer "version_no", default: 1, null: false
-    t.string "source_kind"
-    t.string "source_uri"
-    t.string "source_path"
-    t.string "source_file_id"
-    t.string "normalized_source_key"
-    t.virtual "active_normalized_source_key", type: :string, as: "if((`discarded_at` is null),`normalized_source_key`,NULL)"
-    t.index ["active_normalized_source_key"], name: "index_materials_on_active_normalized_source_key", unique: true
     t.index ["active_url"], name: "index_materials_on_active_url", unique: true
     t.index ["created_by_user_id"], name: "index_materials_on_created_by_user_id"
     t.index ["discarded_at"], name: "index_materials_on_discarded_at"
@@ -298,19 +137,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_07_05_000000) do
     t.index ["target_post_id"], name: "index_post_similarities_on_target_post_id"
   end
 
-  create_table "post_tag_sections", primary_key: ["post_id", "tag_id", "begin_ms"], charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.bigint "post_id", null: false
-    t.bigint "tag_id", null: false
-    t.integer "begin_ms", null: false
-    t.integer "end_ms"
-    t.datetime "created_at", null: false
-    t.datetime "updated_at", null: false
-    t.index ["post_id", "begin_ms"], name: "idx_post_tag_sections_post_id_begin_ms"
-    t.index ["tag_id"], name: "fk_rails_8be3847903"
-    t.check_constraint "(`end_ms` is null) or (`begin_ms` < `end_ms`)", name: "chk_post_tag_sections_end_ms_after_begin_ms"
-    t.check_constraint "`begin_ms` >= 0", name: "chk_post_tag_sections_begin_ms_natural"
-  end
-
   create_table "post_tags", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.bigint "post_id", null: false
     t.bigint "tag_id", null: false
@@ -344,12 +170,9 @@ ActiveRecord::Schema[8.0].define(version: 2026_07_05_000000) do
     t.datetime "original_created_before"
     t.datetime "created_at", null: false
     t.bigint "created_by_user_id"
-    t.integer "video_ms"
     t.index ["created_by_user_id"], name: "index_post_versions_on_created_by_user_id"
     t.index ["post_id", "version_no"], name: "index_post_versions_on_post_id_and_version_no", unique: true
     t.index ["post_id"], name: "index_post_versions_on_post_id"
-    t.index ["video_ms", "post_id"], name: "idx_post_versions_video_ms_post_id"
-    t.check_constraint "(`video_ms` is null) or (`video_ms` > 0)", name: "chk_post_versions_video_ms_positive"
     t.check_constraint "`event_type` in (_utf8mb4'create',_utf8mb4'update',_utf8mb4'discard',_utf8mb4'restore')", name: "post_versions_event_type_valid"
     t.check_constraint "`version_no` > 0", name: "post_versions_version_no_positive"
   end
@@ -364,36 +187,18 @@ ActiveRecord::Schema[8.0].define(version: 2026_07_05_000000) do
     t.datetime "original_created_before"
     t.datetime "updated_at", null: false
     t.integer "version_no", null: false
-    t.integer "video_ms"
     t.index ["uploaded_user_id"], name: "index_posts_on_uploaded_user_id"
     t.index ["url"], name: "index_posts_on_url", unique: true
-    t.index ["video_ms", "id"], name: "idx_posts_video_ms_id"
-    t.check_constraint "(`video_ms` is null) or (`video_ms` > 0)", name: "chk_posts_video_ms_positive"
     t.check_constraint "`version_no` > 0", name: "chk_posts_version_no_positive"
   end
 
   create_table "settings", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.bigint "user_id", null: false
+    t.string "key", null: false
+    t.json "value", null: false
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
-    t.string "theme", default: "system", null: false
-    t.string "auto_fetch_title", default: "manual", null: false
-    t.string "auto_fetch_thumbnail", default: "manual", null: false
-    t.string "wiki_editor_mode", default: "split", null: false
-    t.index ["user_id"], name: "index_settings_on_user_id", unique: true
-  end
-
-  create_table "wiki_assets", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.bigint "wiki_page_id", null: false
-    t.integer "no", null: false
-    t.string "alt_text"
-    t.binary "sha256", limit: 32, null: false
-    t.bigint "created_by_user_id", null: false
-    t.datetime "created_at", null: false
-    t.datetime "updated_at", null: false
-    t.index ["created_by_user_id"], name: "index_wiki_assets_on_created_by_user_id"
-    t.index ["wiki_page_id", "no"], name: "index_wiki_assets_on_wiki_page_id_and_no", unique: true
-    t.index ["wiki_page_id", "sha256"], name: "index_wiki_assets_on_wiki_page_id_and_sha256", unique: true
+    t.index ["user_id"], name: "index_settings_on_user_id"
   end
 
   create_table "tag_implications", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
@@ -443,7 +248,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_07_05_000000) do
     t.string "category", null: false
     t.text "aliases", null: false
     t.text "parent_tag_ids", null: false
-    t.datetime "deprecated_at"
     t.datetime "created_at", null: false
     t.bigint "created_by_user_id"
     t.index ["created_at"], name: "index_tag_versions_on_created_at"
@@ -456,16 +260,13 @@ ActiveRecord::Schema[8.0].define(version: 2026_07_05_000000) do
   create_table "tags", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.bigint "tag_name_id", null: false
     t.string "category", default: "general", null: false
-    t.datetime "deprecated_at"
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
     t.integer "post_count", default: 0, null: false
     t.datetime "discarded_at"
     t.integer "version_no", null: false
-    t.index ["deprecated_at"], name: "index_tags_on_deprecated_at"
     t.index ["discarded_at"], name: "index_tags_on_discarded_at"
     t.index ["tag_name_id"], name: "index_tags_on_tag_name_id", unique: true
-    t.check_constraint "(`deprecated_at` is null) or (`category` <> _utf8mb4'nico')", name: "chk_tags_deprecated_at_not_nico"
     t.check_constraint "`version_no` > 0", name: "chk_tags_version_no_positive"
   end
 
@@ -581,19 +382,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_07_05_000000) do
     t.index ["post_id"], name: "index_user_post_views_on_post_id"
   end
 
-  create_table "user_theme_slots", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.bigint "user_id", null: false
-    t.string "base_theme", null: false
-    t.integer "slot_no", null: false
-    t.json "tokens", null: false
-    t.datetime "created_at", null: false
-    t.datetime "updated_at", null: false
-    t.index ["user_id", "base_theme", "slot_no"], name: "index_user_theme_slots_on_user_theme_and_slot", unique: true
-    t.index ["user_id"], name: "index_user_theme_slots_on_user_id"
-    t.check_constraint "`base_theme` in (_utf8mb4'light',_utf8mb4'dark')", name: "user_theme_slots_base_theme_valid"
-    t.check_constraint "`slot_no` between 1 and 3", name: "user_theme_slots_slot_no_valid"
-  end
-
   create_table "users", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.string "name"
     t.string "inheritance_code", limit: 64, null: false
@@ -604,6 +392,19 @@ ActiveRecord::Schema[8.0].define(version: 2026_07_05_000000) do
     t.index ["banned_at"], name: "index_users_on_banned_at"
   end
 
+  create_table "wiki_assets", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
+    t.bigint "wiki_page_id", null: false
+    t.integer "no", null: false
+    t.string "alt_text"
+    t.binary "sha256", limit: 32, null: false
+    t.bigint "created_by_user_id", null: false
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["created_by_user_id"], name: "index_wiki_assets_on_created_by_user_id"
+    t.index ["wiki_page_id", "no"], name: "index_wiki_assets_on_wiki_page_id_and_no", unique: true
+    t.index ["wiki_page_id", "sha256"], name: "index_wiki_assets_on_wiki_page_id_and_sha256", unique: true
+  end
+
   create_table "wiki_lines", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.string "sha256", limit: 64, null: false
     t.text "body", null: false
@@ -677,24 +478,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_07_05_000000) do
 
   add_foreign_key "active_storage_attachments", "active_storage_blobs", column: "blob_id"
   add_foreign_key "active_storage_variant_records", "active_storage_blobs", column: "blob_id"
-  add_foreign_key "gekanator_ai_runs", "gekanator_question_suggestions"
-  add_foreign_key "gekanator_games", "posts", column: "correct_post_id"
-  add_foreign_key "gekanator_games", "posts", column: "guessed_post_id"
-  add_foreign_key "gekanator_games", "users"
-  add_foreign_key "gekanator_question_examples", "gekanator_games"
-  add_foreign_key "gekanator_question_examples", "gekanator_questions"
-  add_foreign_key "gekanator_question_examples", "posts"
-  add_foreign_key "gekanator_question_examples", "users"
-  add_foreign_key "gekanator_question_suggestions", "gekanator_games", on_delete: :cascade
-  add_foreign_key "gekanator_question_suggestions", "users"
-  add_foreign_key "gekanator_questions", "gekanator_question_suggestions"
-  add_foreign_key "gekanator_questions", "users", column: "created_by_id"
-  add_foreign_key "material_export_items", "materials"
-  add_foreign_key "material_export_items", "users", column: "created_by_user_id"
-  add_foreign_key "material_import_blocks", "users", column: "created_by_user_id"
-  add_foreign_key "material_sync_sources", "users", column: "created_by_user_id"
-  add_foreign_key "material_sync_sources", "users", column: "updated_by_user_id"
-  add_foreign_key "material_sync_suppressions", "users", column: "created_by_user_id"
   add_foreign_key "material_versions", "materials"
   add_foreign_key "material_versions", "materials", column: "parent_id"
   add_foreign_key "material_versions", "tags"
@@ -712,8 +495,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_07_05_000000) do
   add_foreign_key "post_implications", "posts", column: "parent_post_id"
   add_foreign_key "post_similarities", "posts"
   add_foreign_key "post_similarities", "posts", column: "target_post_id"
-  add_foreign_key "post_tag_sections", "posts"
-  add_foreign_key "post_tag_sections", "tags"
   add_foreign_key "post_tags", "posts"
   add_foreign_key "post_tags", "tags"
   add_foreign_key "post_tags", "users", column: "created_user_id"
@@ -753,7 +534,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_07_05_000000) do
   add_foreign_key "user_ips", "users"
   add_foreign_key "user_post_views", "posts"
   add_foreign_key "user_post_views", "users"
-  add_foreign_key "user_theme_slots", "users"
   add_foreign_key "wiki_assets", "users", column: "created_by_user_id"
   add_foreign_key "wiki_assets", "wiki_pages"
   add_foreign_key "wiki_pages", "tag_names"

backend/db/seeds.rb

@@ -7,21 +7,3 @@
 #   ["Action", "Comedy", "Drama", "Horror"].each do |genre_name|
 #     MovieGenre.find_or_create_by!(name: genre_name)
 #   end
-
-material_sync_source_uri = ENV['MATERIAL_SYNC_SOURCE_URI']
-material_sync_source_file_id = ENV['MATERIAL_SYNC_SOURCE_FILE_ID']
-
-if material_sync_source_uri.present? || material_sync_source_file_id.present?
-  source = MaterialSyncSource.find_or_initialize_by(
-      name: ENV.fetch('MATERIAL_SYNC_SOURCE_NAME', 'Legacy URI material sync'))
-  source.assign_attributes(
-      source_kind: ENV.fetch('MATERIAL_SYNC_SOURCE_KIND', 'uri'),
-      source_uri: material_sync_source_uri,
-      source_path: ENV['MATERIAL_SYNC_SOURCE_PATH'],
-      source_file_id: material_sync_source_file_id,
-      profile: ENV.fetch('MATERIAL_SYNC_SOURCE_PROFILE', 'legacy_drive'),
-      enabled: ENV.fetch('MATERIAL_SYNC_SOURCE_ENABLED', 'true') != 'false',
-      default_tag_name: ENV['MATERIAL_SYNC_SOURCE_TAG_NAME'],
-      export_path_prefix: ENV['MATERIAL_SYNC_EXPORT_PATH_PREFIX'])
-  source.save!
-end

backend/lib/tasks/calc_post_similarities.rake

@@ -1,6 +1,6 @@
 namespace :post_similarity do
   desc '関聯投稿テーブル作成'
   task calc: :environment do
-    Similarity::Calc.call(Post, :active_tags)
+    Similarity::Calc.call(Post, :tags)
   end
 end

backend/lib/tasks/calc_tag_similarities.rake

@@ -1,6 +1,6 @@
 namespace :tag_similarity do
   desc '関聯タグ・テーブル作成'
   task calc: :environment do
-    Similarity::Calc.call(Tag, :posts, scope: Tag.where(deprecated_at: nil))
+    Similarity::Calc.call(Tag, :posts)
   end
 end

backend/lib/tasks/sync_materials.rake

@@ -1,51 +0,0 @@
-namespace :materials do
-  desc '素材同期'
-  task sync: :environment do
-    result = MaterialSyncRunner.sync_enabled!
-    message = [
-      "materials:sync imported=#{ result.imported }",
-      "updated=#{ result.updated }",
-      "unchanged=#{ result.unchanged }",
-      "suppressed=#{ result.suppressed }",
-      "failed=#{ result.failed }"
-    ].join(' ')
-
-    Rails.logger.info(message)
-    puts message
-
-    result.errors.each do |error|
-      Rails.logger.warn(error.to_json)
-      warn error.to_json
-    end
-  end
-
-  namespace :thumbnails do
-    desc '素材サムネールを補完'
-    task backfill: :environment do
-      counts = Hash.new(0)
-
-      Material
-        .with_attached_file
-        .with_attached_thumbnail
-        .find_each do |material|
-          next unless material.file.attached?
-          next if material.thumbnail.attached?
-
-          result = MaterialThumbnailGenerator.generate!(material)
-          counts[result] += 1
-        end
-
-      message =
-          "materials:thumbnails:backfill " \
-          "attached=#{ counts[:attached] } " \
-          "no_file=#{ counts[:no_file] } " \
-          "unsupported_content_type=#{ counts[:unsupported_content_type] } " \
-          "generation_failed=#{ counts[:generation_failed] } " \
-          "attach_failed=#{ counts[:attach_failed] } " \
-          "file_not_found=#{ counts[:file_not_found] } " \
-          "mini_magick_error=#{ counts[:mini_magick_error] }"
-      Rails.logger.info(message)
-      puts message
-    end
-  end
-end

backend/spec/factories/post_tag_sections.rb

@@ -1,8 +0,0 @@
-FactoryBot.define do
-  factory :post_tag_section do
-    association :post
-    association :tag
-    begin_ms { 1_000 }
-    end_ms { 2_000 }
-  end
-end

backend/spec/factories/post_tags.rb

@@ -1,6 +0,0 @@
-FactoryBot.define do
-  factory :post_tag do
-    association :post
-    association :tag
-  end
-end

backend/spec/factories/posts.rb

@@ -1,8 +0,0 @@
-FactoryBot.define do
-  factory :post do
-    sequence(:url) { |n| "https://example.com/factory-post-#{ n }" }
-    title { 'factory post' }
-    thumbnail_base { nil }
-    uploaded_user { nil }
-  end
-end

backend/spec/models/material_export_item_spec.rb

@@ -1,57 +0,0 @@
-require 'rails_helper'
-
-RSpec.describe MaterialExportItem, type: :model do
-  let(:user) { create(:user, :member) }
-  let(:tag) { Tag.create!(tag_name: TagName.create!(name: 'export_item'), category: :material) }
-  let(:material) do
-    Material.create!(tag:, url: 'https://example.com/material',
-                     created_by_user: user, updated_by_user: user)
-  end
-
-  it 'rejects blank export_path' do
-    item = described_class.new(material:, profile: 'legacy_drive', export_path: '')
-
-    expect(item).not_to be_valid
-    expect(item.errors[:export_path]).to be_present
-  end
-
-  it 'rejects absolute export_path' do
-    item = described_class.new(material:, profile: 'legacy_drive',
-                               export_path: '/素材/a.png')
-
-    expect(item).not_to be_valid
-    expect(item.errors[:export_path]).to be_present
-  end
-
-  it 'rejects parent traversal export_path' do
-    item = described_class.new(material:, profile: 'legacy_drive',
-                               export_path: '素材/../a.png')
-
-    expect(item).not_to be_valid
-    expect(item.errors[:export_path]).to be_present
-  end
-
-  it 'rejects double slash export_path' do
-    item = described_class.new(material:, profile: 'legacy_drive',
-                               export_path: '素材//a.png')
-
-    expect(item).not_to be_valid
-    expect(item.errors[:export_path]).to be_present
-  end
-
-  it 'rejects dot segment export_path' do
-    item = described_class.new(material:, profile: 'legacy_drive',
-                               export_path: './素材/a.png')
-
-    expect(item).not_to be_valid
-    expect(item.errors[:export_path]).to be_present
-  end
-
-  it 'rejects trailing slash export_path' do
-    item = described_class.new(material:, profile: 'legacy_drive',
-                               export_path: '素材/a/')
-
-    expect(item).not_to be_valid
-    expect(item.errors[:export_path]).to be_present
-  end
-end

backend/spec/models/material_spec.rb

@@ -1,19 +0,0 @@
-require 'rails_helper'
-
-RSpec.describe Material, type: :model do
-  let(:user) { create(:user, :member) }
-
-  it 'allows only material source kinds, not suppression prefix kinds' do
-    material = described_class.new(url: 'https://example.com/material',
-                                   source_kind: 'google_drive_path_prefix',
-                                   source_path: '素材/危険',
-                                   created_by_user: user,
-                                   updated_by_user: user)
-
-    expect(material).not_to be_valid
-    expect(material.errors[:source_kind]).to be_present
-
-    material.source_kind = 'google_drive_path'
-    expect(material).to be_valid
-  end
-end

backend/spec/models/post_tag_spec.rb

@@ -1,41 +0,0 @@
-RSpec.describe PostTag, type: :model do
-  describe '#sections' do
-    it 'loads sections by post_id and tag_id' do
-      post_tag = create(:post_tag)
-      section = create(:post_tag_section,
-                       post: post_tag.post,
-                       tag: post_tag.tag,
-                       begin_ms: 1000,
-                       end_ms: 2000)
-
-      expect(post_tag.sections).to contain_exactly(section)
-    end
-
-    it 'does not load sections for another tag on the same post' do
-      post = create(:post)
-      tag = create(:tag)
-      other_tag = create(:tag)
-
-      post_tag = create(:post_tag, post:, tag:)
-      create(:post_tag_section,
-             post:,
-             tag: other_tag,
-             begin_ms: 1000,
-             end_ms: 2000)
-
-      expect(post_tag.sections).to be_empty
-    end
-
-    it 'allows open-ended sections' do
-      post_tag = create(:post_tag)
-      section = create(:post_tag_section,
-                       post: post_tag.post,
-                       tag: post_tag.tag,
-                       begin_ms: 1000,
-                       end_ms: nil)
-
-      expect(section).to be_valid
-      expect(post_tag.sections).to contain_exactly(section)
-    end
-  end
-end

backend/spec/models/setting_spec.rb

@@ -1,34 +0,0 @@
-require 'rails_helper'
-
-RSpec.describe Setting, type: :model do
-  it 'accepts the default typed user settings' do
-    setting = described_class.new({ user: create(:user) }.merge(described_class.defaults))
-
-    expect(setting).to be_valid
-  end
-
-  it 'requires one settings row per user' do
-    user = create(:user)
-    described_class.create!({ user: }.merge(described_class.defaults))
-
-    duplicate = described_class.new({ user: }.merge(described_class.defaults))
-
-    expect(duplicate).not_to be_valid
-    expect(duplicate.errors[:user_id]).to be_present
-  end
-
-  it 'validates enum-like settings columns' do
-    setting = described_class.new(
-        { user: create(:user),
-          theme: 'neon',
-          auto_fetch_title: 'sometimes',
-          auto_fetch_thumbnail: 'sometimes',
-          wiki_editor_mode: 'sideways' })
-
-    expect(setting).not_to be_valid
-    expect(setting.errors[:theme]).to be_present
-    expect(setting.errors[:auto_fetch_title]).to be_present
-    expect(setting.errors[:auto_fetch_thumbnail]).to be_present
-    expect(setting.errors[:wiki_editor_mode]).to be_present
-  end
-end

backend/spec/models/tag_implication_spec.rb

@@ -1,36 +0,0 @@
-require 'rails_helper'
-
-RSpec.describe TagImplication, type: :model do
-  it 'rejects a parent tag that would create a cycle' do
-    child = create(:tag, name: 'tag_implication_cycle_child')
-    parent = create(:tag, name: 'tag_implication_cycle_parent')
-
-    described_class.create!(tag: child, parent_tag: parent)
-
-    implication = described_class.new(tag: parent, parent_tag: child)
-
-    expect(implication).not_to be_valid
-    expect(implication.errors[:parent_tag_id]).to include(
-      '親タグに子孫タグを指定すると循環します．'
-    )
-    expect(implication.errors[:base]).to be_present
-  end
-
-  it 'terminates even when existing data already contains a cycle' do
-    child = create(:tag, name: 'tag_implication_existing_cycle_child')
-    parent = create(:tag, name: 'tag_implication_existing_cycle_parent')
-    ancestor = create(:tag, name: 'tag_implication_existing_cycle_ancestor')
-
-    described_class.create!(tag: parent, parent_tag: ancestor)
-    described_class.insert_all!(
-      [
-        { tag_id: ancestor.id, parent_tag_id: parent.id,
-          created_at: Time.current, updated_at: Time.current }
-      ]
-    )
-
-    implication = described_class.new(tag: child, parent_tag: parent)
-
-    expect(implication).to be_valid
-  end
-end

backend/spec/models/tag_name_sanitisation_rule_spec.rb

@@ -1,10 +1,6 @@
 require 'rails_helper'
 
 RSpec.describe TagNameSanitisationRule, type: :model do
-  before do
-    described_class.unscoped.delete_all
-  end
-
   describe '.sanitise' do
     before do
       described_class.create!(priority: 10, source_pattern: '_', replacement: '')

backend/spec/models/tag_spec.rb

@@ -1,178 +1,6 @@
 require 'rails_helper'
 
 RSpec.describe Tag, type: :model do
-  describe '.normalise_tags!' do
-    it 'rejects deprecated tags when deny_deprecated is enabled' do
-      tag_name = TagName.create!(name: 'normalise deprecated tag')
-      deprecated_tag = Tag.create!(
-        tag_name:,
-        category: :general,
-        deprecated_at: 1.day.from_now
-      )
-
-      expect {
-        described_class.normalise_tags!(
-          [deprecated_tag.name],
-          deny_deprecated: true
-        )
-      }.to raise_error(Tag::DeprecatedTagNormalisationError) { |error|
-        expect(error.tag_names).to eq([deprecated_tag.name])
-      }
-    end
-
-    it 'rejects invalid section literals instead of treating them as zero' do
-      expect {
-        described_class.normalise_tags!(
-          ['normalise_invalid_section[1:aa-2:00]'],
-          with_sections: true
-        )
-      }.to raise_error(Tag::SectionLiteralParseError)
-    end
-
-    it 'parses open-ended section literals' do
-      result = described_class.normalise_tags!(
-        ['伊地知ニジカ[1:00-]'],
-        with_sections: true
-      )
-
-      tag = result.fetch(:tags).find { _1.name == '伊地知ニジカ' }
-      expect(result.fetch(:sections).fetch(tag.id)).to eq([[60_000, nil]])
-    end
-
-    it 'parses omitted begin as zero' do
-      result = described_class.normalise_tags!(
-        ['伊地知ニジカ[-1:00]'],
-        with_sections: true
-      )
-
-      tag = result.fetch(:tags).find { _1.name == '伊地知ニジカ' }
-      expect(result.fetch(:sections).fetch(tag.id)).to eq([[0, 60_000]])
-    end
-
-    it 'treats fully open section literals as plain tags' do
-      result = described_class.normalise_tags!(
-        ['伊地知ニジカ[-]'],
-        with_sections: true
-      )
-
-      tag = result.fetch(:tags).find { _1.name == '伊地知ニジカ' }
-      expect(result.fetch(:sections)[tag.id]).to be_nil
-    end
-
-    it 'treats [0:00-] as a plain tag' do
-      result = described_class.normalise_tags!(
-        ['伊地知ニジカ[0:00-]'],
-        with_sections: true
-      )
-
-      tag = result.fetch(:tags).find { _1.name == '伊地知ニジカ' }
-      expect(result.fetch(:sections)[tag.id]).to be_nil
-    end
-
-    it 'expands zero-width sections to one millisecond' do
-      result = described_class.normalise_tags!(
-        ['伊地知ニジカ[1:00-1:00]'],
-        with_sections: true
-      )
-
-      tag = result.fetch(:tags).find { _1.name == '伊地知ニジカ' }
-      expect(result.fetch(:sections).fetch(tag.id)).to eq([[60_000, 60_001]])
-    end
-
-    it 'swaps reversed section boundaries' do
-      result = described_class.normalise_tags!(
-        ['伊地知ニジカ[2:00-1:00]'],
-        with_sections: true
-      )
-
-      tag = result.fetch(:tags).find { _1.name == '伊地知ニジカ' }
-      expect(result.fetch(:sections).fetch(tag.id)).to eq([[60_000, 120_000]])
-    end
-
-    it 'merges open-ended sections over later bounded sections' do
-      result = described_class.normalise_tags!(
-        ['伊地知ニジカ[1:00-][2:00-3:00]'],
-        with_sections: true
-      )
-
-      tag = result.fetch(:tags).find { _1.name == '伊地知ニジカ' }
-      expect(result.fetch(:sections).fetch(tag.id)).to eq([[60_000, nil]])
-    end
-
-    it 'merges adjacent bounded and open-ended sections' do
-      result = described_class.normalise_tags!(
-        ['伊地知ニジカ[1:00-3:00][3:00-]'],
-        with_sections: true
-      )
-
-      tag = result.fetch(:tags).find { _1.name == '伊地知ニジカ' }
-      expect(result.fetch(:sections).fetch(tag.id)).to eq([[60_000, nil]])
-    end
-  end
-
-  describe '.expand_parent_tags' do
-    it 'expands through multiple deprecated parents to an active ancestor' do
-      child = create(:tag, name: 'expand_child')
-      deprecated_parent = create(
-        :tag,
-        name: 'expand_deprecated_parent',
-        deprecated_at: Time.current
-      )
-      deprecated_grandparent = create(
-        :tag,
-        name: 'expand_deprecated_grandparent',
-        deprecated_at: Time.current
-      )
-      active_ancestor = create(:tag, name: 'expand_active_ancestor')
-      TagImplication.create!(tag: child, parent_tag: deprecated_parent)
-      TagImplication.create!(tag: deprecated_parent, parent_tag: deprecated_grandparent)
-      TagImplication.create!(tag: deprecated_grandparent, parent_tag: active_ancestor)
-
-      expanded = described_class.expand_parent_tags([child])
-
-      expect(expanded).to include(
-        child,
-        deprecated_parent,
-        deprecated_grandparent,
-        active_ancestor
-      )
-      expect(expanded.reject(&:deprecated?)).to contain_exactly(child, active_ancestor)
-    end
-
-    it 'terminates when implications contain a cycle' do
-      first = create(:tag, name: 'expand_cycle_first')
-      second = create(:tag, name: 'expand_cycle_second')
-      TagImplication.create!(tag: first, parent_tag: second)
-      now = Time.current
-      TagImplication.insert_all!(
-        [
-          {
-            tag_id: second.id,
-            parent_tag_id: first.id,
-            created_at: now,
-            updated_at: now
-          }
-        ]
-      )
-
-      expect(described_class.expand_parent_tags([first])).to contain_exactly(first, second)
-    end
-  end
-
-  describe 'deprecated validation' do
-    it 'rejects deprecated nico tags' do
-      tag = build(
-        :tag,
-        name: 'nico:deprecated_validation',
-        category: :nico,
-        deprecated_at: Time.current
-      )
-
-      expect(tag).not_to be_valid
-      expect(tag.errors[:deprecated_at]).to include('ニコタグは廃止できません．')
-    end
-  end
-
   describe '.merge_tags!' do
     let!(:target_tag) { create(:tag, category: :general) }
     let!(:source_tag) { create(:tag, category: :general) }

backend/spec/models/user_theme_slot_spec.rb

@@ -1,40 +0,0 @@
-require 'rails_helper'
-
-RSpec.describe UserThemeSlot, type: :model do
-  it 'accepts a theme slot for one user, base theme, and slot number' do
-    slot = described_class.new(user: create(:user),
-                               base_theme: 'light',
-                               slot_no: 1,
-                               tokens: { 'background' => '0 0% 100%' })
-
-    expect(slot).to be_valid
-  end
-
-  it 'requires unique slot numbers per user and base theme' do
-    user = create(:user)
-    described_class.create!(user:,
-                            base_theme: 'dark',
-                            slot_no: 2,
-                            tokens: { 'background' => '222.2 84% 4.9%' })
-
-    duplicate = described_class.new(user:,
-                                    base_theme: 'dark',
-                                    slot_no: 2,
-                                    tokens: { 'background' => '0 0% 100%' })
-
-    expect(duplicate).not_to be_valid
-    expect(duplicate.errors[:user_id]).to be_present
-  end
-
-  it 'validates base theme, slot number, and token object shape' do
-    slot = described_class.new(user: create(:user),
-                               base_theme: 'system',
-                               slot_no: 4,
-                               tokens: 'not-object')
-
-    expect(slot).not_to be_valid
-    expect(slot.errors[:base_theme]).to be_present
-    expect(slot.errors[:slot_no]).to be_present
-    expect(slot.errors[:tokens]).to be_present
-  end
-end

backend/spec/requests/gekanator_games_spec.rb

@@ -1,76 +0,0 @@
-require 'rails_helper'
-
-RSpec.describe 'Gekanator games API', type: :request do
-  let!(:admin) { create_admin_user! }
-  let!(:user) { create_member_user! }
-  let!(:guessed_post) { Post.create!(title: 'guess', url: 'https://example.com/guess') }
-  let!(:correct_post) { Post.create!(title: 'correct', url: 'https://example.com/correct') }
-
-  describe 'POST /gekanator/games' do
-    it 'stores a won game' do
-      sign_in_as admin
-
-      post '/gekanator/games', params: {
-          guessed_post_id: guessed_post.id,
-          correct_post_id: guessed_post.id,
-          answers: [{ question_id: 'tag:1', answer: 'yes' }] }
-
-      expect(response).to have_http_status(:created)
-      game = GekanatorGame.find(json['id'])
-      expect(game.user).to eq(admin)
-      expect(game.guessed_post).to eq(guessed_post)
-      expect(game.correct_post).to eq(guessed_post)
-      expect(game.won).to eq(true)
-      expect(game.question_count).to eq(1)
-      expect(game.answers).to eq([{ 'question_id' => 'tag:1', 'answer' => 'yes' }])
-    end
-
-    it 'stores a lost game with the correct post' do
-      sign_in_as admin
-
-      post '/gekanator/games', params: {
-          guessed_post_id: guessed_post.id,
-          correct_post_id: correct_post.id,
-          question_count: 4,
-          answers: [{ question_id: 'tag:1', answer: 'no' }] }
-
-      expect(response).to have_http_status(:created)
-      game = GekanatorGame.find(json['id'])
-      expect(game.correct_post).to eq(correct_post)
-      expect(game.won).to eq(false)
-      expect(game.question_count).to eq(1)
-    end
-
-    it 'rejects a game without the correct post' do
-      sign_in_as admin
-
-      post '/gekanator/games', params: {
-          guessed_post_id: guessed_post.id,
-          question_count: 4,
-          answers: [{ question_id: 'tag:1', answer: 'no' }] }
-
-      expect(response).to have_http_status(:unprocessable_entity)
-    end
-
-    it 'returns unauthorized without a user' do
-      post '/gekanator/games', params: {
-          guessed_post_id: guessed_post.id,
-          correct_post_id: guessed_post.id,
-          answers: [] }
-
-      expect(response).to have_http_status(:unauthorized)
-    end
-
-    it 'stores a game for a non-admin user' do
-      sign_in_as user
-
-      post '/gekanator/games', params: {
-          guessed_post_id: guessed_post.id,
-          correct_post_id: guessed_post.id,
-          answers: [{ question_id: 'tag:1', answer: 'yes' }] }
-
-      expect(response).to have_http_status(:created)
-      expect(GekanatorGame.find(json['id']).user).to eq(user)
-    end
-  end
-end

backend/spec/requests/gekanator_posts_spec.rb

@@ -1,33 +0,0 @@
-require 'rails_helper'
-
-
-RSpec.describe 'Gekanator posts API', type: :request do
-  describe 'GET /gekanator/posts' do
-    it 'omits deprecated tags and returns the stored similarity cosine' do
-      active_tag = Tag.create!(name: 'active tag', category: :general)
-      deprecated_tag = Tag.create!(
-        name: 'deprecated tag',
-        category: :general,
-        deprecated_at: Time.current
-      )
-      post_record = Post.create!(title: 'source', url: 'https://example.com/source')
-      target_post = Post.create!(title: 'target', url: 'https://example.com/target')
-
-      PostTag.create!(post: post_record, tag: active_tag)
-      PostTag.create!(post: post_record, tag: deprecated_tag)
-      PostTag.create!(post: target_post, tag: deprecated_tag)
-      PostSimilarity.create!(post: post_record, target_post:, cos: 0.375)
-
-      get '/gekanator/posts'
-
-      expect(response).to have_http_status(:ok)
-
-      post_json = json.fetch('posts').find { |post| post.fetch('id') == post_record.id }
-      expect(post_json.fetch('tags').map { |tag| tag.fetch('name') }).to eq(['active tag'])
-      expect(post_json.fetch('post_similarity_edges')).to contain_exactly(
-        'target_post_id' => target_post.id,
-        'cos' => 0.375
-      )
-    end
-  end
-end

backend/spec/requests/materials_spec.rb

@@ -1,10 +1,7 @@
 require 'rails_helper'
 
 RSpec.describe 'Materials API', type: :request do
-  include ActiveJob::TestHelper
-
   let!(:member_user) { create(:user, :member) }
-  let!(:admin_user)  { create(:user, :admin) }
   let!(:guest_user)  { create(:user) }
 
   def dummy_upload(filename: 'dummy.png', type: 'image/png', body: 'dummy')
@@ -16,29 +13,22 @@ RSpec.describe 'Materials API', type: :request do
   end
 
   def build_material(tag:, user:, parent: nil, file: dummy_upload, url: nil)
-    Material.new(tag:, parent:, url:,
-                 created_by_user: user,
-                 updated_by_user: user).tap do |material|
+    Material.new(tag:, parent:, url:, created_by_user: user, updated_by_user: user).tap do |material|
       material.file.attach(file) if file
       material.save!
     end
   end
 
   describe 'GET /materials' do
-    let!(:tag_a) do
-      Tag.create!(tag_name: TagName.create!(name: 'material_index_a'), category: :material)
-    end
-    let!(:tag_b) do
-      Tag.create!(tag_name: TagName.create!(name: 'material_index_b'), category: :material)
-    end
+    let!(:tag_a) { Tag.create!(tag_name: TagName.create!(name: 'material_index_a'), category: :material) }
+    let!(:tag_b) { Tag.create!(tag_name: TagName.create!(name: 'material_index_b'), category: :material) }
 
     let!(:material_a) do
       build_material(tag: tag_a, user: member_user, file: dummy_upload(filename: 'a.png'))
     end
 
     let!(:material_b) do
-      build_material(tag: tag_b, user: member_user, parent: material_a,
-                     file: dummy_upload(filename: 'b.png'))
+      build_material(tag: tag_b, user: member_user, parent: material_a, file: dummy_upload(filename: 'b.png'))
     end
 
     before do
@@ -64,36 +54,27 @@ RSpec.describe 'Materials API', type: :request do
         'name' => 'material_index_b',
         'category' => 'material'
       )
+      expect(row['created_by_user']).to include(
+        'id' => member_user.id,
+        'name' => member_user.name
+      )
       expect(row['content_type']).to eq('image/png')
-      expect(row['media_kind']).to eq('image')
     end
 
-    it 'filters materials by q' do
-      get '/materials', params: { q: 'material_index_a' }
+    it 'filters materials by tag_id' do
+      get '/materials', params: { tag_id: material_a.tag_id }
 
       expect(response).to have_http_status(:ok)
       expect(json['count']).to eq(1)
       expect(response_materials.map { |m| m['id'] }).to eq([material_a.id])
     end
 
-    it 'filters materials by tag_state' do
-      untagged =
-          build_material(tag: nil, user: member_user,
-                         file: dummy_upload(filename: 'untagged.png'))
-
-      get '/materials', params: { tag_state: 'untagged' }
+    it 'filters materials by parent_id' do
+      get '/materials', params: { parent_id: material_a.id }
 
       expect(response).to have_http_status(:ok)
       expect(json['count']).to eq(1)
-      expect(response_materials.map { |m| m['id'] }).to eq([untagged.id])
-    end
-
-    it 'filters materials by media_kind' do
-      get '/materials', params: { media_kind: 'image' }
-
-      expect(response).to have_http_status(:ok)
-      expect(json['count']).to eq(2)
-      expect(response_materials.map { |m| m['media_kind'] }).to all(eq('image'))
+      expect(response_materials.map { |m| m['id'] }).to eq([material_b.id])
     end
 
     it 'paginates and keeps total count' do
@@ -113,74 +94,10 @@ RSpec.describe 'Materials API', type: :request do
       expect(response_materials.size).to eq(1)
       expect(response_materials.first['id']).to eq(material_b.id)
     end
-
-    it 'filters by descendant tags and returns stable parent tag groups' do
-      root =
-          Tag.create!(tag_name: TagName.create!(name: 'material_scope_root'),
-                      category: :material)
-      child_b =
-          Tag.create!(tag_name: TagName.create!(name: 'material_scope_b'),
-                      category: :material)
-      child_a =
-          Tag.create!(tag_name: TagName.create!(name: 'material_scope_a'),
-                      category: :material)
-      deprecated =
-          Tag.create!(tag_name: TagName.create!(name: 'material_scope_old'),
-                      category: :material,
-                      deprecated_at: Time.current)
-      grandchild =
-          Tag.create!(tag_name: TagName.create!(name: 'material_scope_grandchild'),
-                      category: :material)
-      root_material =
-          build_material(tag: root, user: member_user,
-                         file: dummy_upload(filename: 'root.png'))
-      child_a_material =
-          build_material(tag: child_a, user: member_user,
-                         file: dummy_upload(filename: 'child_a.png'))
-      grandchild_material =
-          build_material(tag: grandchild, user: member_user,
-                         file: dummy_upload(filename: 'grandchild.png'))
-
-      TagImplication.create!(parent_tag: root, tag: child_b)
-      TagImplication.create!(parent_tag: root, tag: child_a)
-      TagImplication.create!(parent_tag: child_b, tag: deprecated)
-      TagImplication.create!(parent_tag: deprecated, tag: grandchild)
-
-      get '/materials',
-          params: { tag_id: root.id, include_descendants: '1',
-                    group_by: 'parent_tag', sort: 'id', direction: 'asc' }
-
-      expect(response).to have_http_status(:ok)
-      expect(response_materials.map { |m| m['id'] })
-        .to include(root_material.id, child_a_material.id, grandchild_material.id)
-      expect(json['tag_scope']).to eq(
-        'tag' => {
-          'id' => root.id,
-          'name' => 'material_scope_root',
-          'category' => 'material'
-        },
-        'include_descendants' => true
-      )
-      expect(json['groups'].map { |group| group.dig('tag', 'name') })
-        .to eq(['material_scope_a', 'material_scope_b', 'material_scope_root'])
-      expect(json['groups'].find { |group| group.dig('tag', 'id') == child_b.id }
-        .fetch('material_ids')).to eq([grandchild_material.id])
-    end
-
-    it 'returns nil tag_scope when tag_id is unknown' do
-      get '/materials', params: { tag_id: 999_999, group_by: 'parent_tag' }
-
-      expect(response).to have_http_status(:ok)
-      expect(json['tag_scope']).to be_nil
-      expect(json['groups']).to eq([])
-      expect(response_materials).to eq([])
-    end
   end
 
   describe 'GET /materials/:id' do
-    let!(:tag) do
-      Tag.create!(tag_name: TagName.create!(name: 'material_show'), category: :material)
-    end
+    let!(:tag) { Tag.create!(tag_name: TagName.create!(name: 'material_show'), category: :material) }
     let!(:material) do
       build_material(tag:, user: member_user, file: dummy_upload(filename: 'show.png'))
     end
@@ -221,22 +138,9 @@ RSpec.describe 'Materials API', type: :request do
       end
     end
 
-    context 'when logged in but not member' do
+    context 'when logged in' do
       before { sign_in_as(guest_user) }
 
-      it 'returns 403' do
-        post '/materials', params: {
-          tag: 'material_create_guest_forbidden',
-          file: dummy_upload
-        }
-
-        expect(response).to have_http_status(:forbidden)
-      end
-    end
-
-    context 'when member' do
-      before { sign_in_as(member_user) }
-
       it 'returns 422 when tag is blank' do
         post '/materials', params: { tag: '   ', file: dummy_upload }
 
@@ -258,49 +162,24 @@ RSpec.describe 'Materials API', type: :request do
         expect do
           post '/materials', params: {
             tag: 'material_create_new',
-            file: dummy_upload(filename: 'created.png'),
-            export_paths: { legacy_drive: '伊地知ニジカ/created.png' }
+            file: dummy_upload(filename: 'created.png')
           }
         end.to change(Material, :count).by(1)
           .and change(Tag, :count).by(1)
           .and change(TagName, :count).by(1)
-          .and change(MaterialVersion, :count).by(1)
 
         expect(response).to have_http_status(:created)
 
         material = Material.order(:id).last
         expect(material.tag.name).to eq('material_create_new')
         expect(material.tag.category).to eq('material')
-        expect(material.created_by_user).to eq(member_user)
-        expect(material.updated_by_user).to eq(member_user)
+        expect(material.created_by_user).to eq(guest_user)
+        expect(material.updated_by_user).to eq(guest_user)
         expect(material.file.attached?).to be(true)
-        expect(material.version_no).to eq(1)
-        expect(material.material_versions.first.event_type).to eq('create')
-        expect(material.material_export_items.first.export_path).to eq('伊地知ニジカ/created.png')
-        expect(material.material_versions.first.export_paths_json).to eq(
-          'legacy_drive' => '伊地知ニジカ/created.png'
-        )
 
         expect(json['id']).to eq(material.id)
         expect(json.dig('tag', 'name')).to eq('material_create_new')
         expect(json['content_type']).to eq('image/png')
-        expect(json.dig('export_paths', 'legacy_drive')).to eq('伊地知ニジカ/created.png')
-      end
-
-      it 'snapshots attached file metadata and sha256' do
-        post '/materials', params: {
-          tag: 'material_create_file_version',
-          file: dummy_upload(filename: 'created.png', body: 'sha-body')
-        }
-
-        expect(response).to have_http_status(:created)
-
-        version = Material.order(:id).last.material_versions.first
-        expect(version.file_blob_id).to be_present
-        expect(version.file_filename).to eq('created.png')
-        expect(version.file_content_type).to eq('image/png')
-        expect(version.file_byte_size).to eq('sha-body'.bytesize)
-        expect(version.file_sha256).to eq(Digest::SHA256.hexdigest('sha-body'))
       end
 
       it 'returns 422 when the existing tag is not material/character' do
@@ -340,33 +219,11 @@ RSpec.describe 'Materials API', type: :request do
         expect(response).to have_http_status(:created)
         expect(json['url']).to eq('https://example.com/material-source')
       end
-
-      it 'rejects sha256-blocked file upload' do
-        sha256 = Digest::SHA256.hexdigest('blocked-body')
-        MaterialImportBlock.create!(match_kind: 'sha256',
-                                    sha256:,
-                                    reason: 'copyright_high_risk',
-                                    created_by_user: admin_user)
-
-        expect do
-          post '/materials', params: {
-            tag: 'material_blocked_create',
-            file: dummy_upload(filename: 'blocked.png', body: 'blocked-body')
-          }
-        end.not_to change(Material, :count)
-
-        expect(response).to have_http_status(:unprocessable_entity)
-        expect(json.fetch('errors')).to include(
-          'file' => ['抑止された素材です: copyright_high_risk']
-        )
-      end
     end
   end
 
   describe 'PUT /materials/:id' do
-    let!(:tag) do
-      Tag.create!(tag_name: TagName.create!(name: 'material_update_old'), category: :material)
-    end
+    let!(:tag) { Tag.create!(tag_name: TagName.create!(name: 'material_update_old'), category: :material) }
     let!(:material) do
       build_material(tag:, user: member_user, file: dummy_upload(filename: 'old.png'))
     end
@@ -420,26 +277,25 @@ RSpec.describe 'Materials API', type: :request do
             'tag' => ['タグは必須です．'])
       end
 
-      it 'keeps the existing file when file and url are omitted' do
+      it 'returns 422 when both file and url are blank' do
         put "/materials/#{ material.id }", params: {
           tag: 'material_update_no_payload'
         }
 
-        expect(response).to have_http_status(:ok)
-        expect(material.reload.file.attached?).to be(true)
+        expect(response).to have_http_status(:unprocessable_entity)
+        expect(json.fetch('errors')).to include(
+            'file' => ['ファイルまたは URL は必須です．'],
+            'url' => ['ファイルまたは URL は必須です．'])
       end
 
       it 'updates tag, url, file, and updated_by_user' do
         old_blob_id = material.file.blob.id
 
-        expect do
-          put "/materials/#{ material.id }", params: {
-            tag: 'material_update_new',
-            url: 'https://example.com/updated-source',
-            file: dummy_upload(filename: 'updated.jpg', type: 'image/jpeg'),
-            export_paths: { legacy_drive: '伊地知ニジカ/updated.jpg' }
-          }
-        end.to change(MaterialVersion, :count).by(2)
+        put "/materials/#{ material.id }", params: {
+          tag: 'material_update_new',
+          url: 'https://example.com/updated-source',
+          file: dummy_upload(filename: 'updated.jpg', type: 'image/jpeg')
+        }
 
         expect(response).to have_http_status(:ok)
 
@@ -450,15 +306,8 @@ RSpec.describe 'Materials API', type: :request do
         expect(material.updated_by_user).to eq(member_user)
         expect(material.file.attached?).to be(true)
         expect(material.file.blob.id).not_to eq(old_blob_id)
-        expect(ActiveStorage::Blob.where(id: old_blob_id).exists?).to be(true)
         expect(material.file.blob.filename.to_s).to eq('updated.jpg')
         expect(material.file.blob.content_type).to eq('image/jpeg')
-        expect(material.version_no).to eq(2)
-        expect(material.material_versions.order(:version_no).last.event_type).to eq('update')
-        expect(material.material_export_items.first.export_path).to eq('伊地知ニジカ/updated.jpg')
-        expect(material.material_versions.order(:version_no).last.export_paths_json).to eq(
-          'legacy_drive' => '伊地知ニジカ/updated.jpg'
-        )
 
         expect(json['id']).to eq(material.id)
         expect(json['file']).to be_present
@@ -466,7 +315,7 @@ RSpec.describe 'Materials API', type: :request do
         expect(json.dig('tag', 'name')).to eq('material_update_new')
       end
 
-      it 'detaches the existing file without purging blob when url replaces file' do
+      it 'purges the existing file when file is omitted and url is provided' do
         old_blob_id = material.file.blob.id
 
         put "/materials/#{ material.id }", params: {
@@ -482,7 +331,9 @@ RSpec.describe 'Materials API', type: :request do
         expect(material.updated_by_user).to eq(member_user)
         expect(material.file.attached?).to be(false)
 
-        expect(ActiveStorage::Blob.where(id: old_blob_id).exists?).to be(true)
+        expect(
+          ActiveStorage::Blob.where(id: old_blob_id).exists?
+        ).to be(false)
 
         expect(json['id']).to eq(material.id)
         expect(json['file']).to be_nil
@@ -490,205 +341,11 @@ RSpec.describe 'Materials API', type: :request do
         expect(json.dig('tag', 'name')).to eq('material_update_remove_file')
         expect(json['url']).to eq('https://example.com/updated-source')
       end
-
-      it 'does not increase version for the same snapshot update' do
-        MaterialVersionRecorder.record!(material:, event_type: :create,
-                                        created_by_user: member_user)
-
-        expect do
-          put "/materials/#{ material.id }", params: {
-            tag: 'material_update_old'
-          }
-        end.not_to change(MaterialVersion, :count)
-
-        expect(response).to have_http_status(:ok)
-        expect(material.reload.version_no).to eq(1)
-      end
-
-      it 'records update version when only export_path changes' do
-        MaterialVersionRecorder.record!(material:, event_type: :create,
-                                        created_by_user: member_user)
-
-        expect do
-          put "/materials/#{ material.id }", params: {
-            tag: 'material_update_old',
-            export_paths: { legacy_drive: '素材/only-path.png' }
-          }
-        end.to change(MaterialVersion, :count).by(1)
-
-        expect(response).to have_http_status(:ok)
-        expect(material.reload.material_export_items.first.export_path).to eq('素材/only-path.png')
-        expect(material.material_versions.order(:version_no).last.export_paths_json).to eq(
-          'legacy_drive' => '素材/only-path.png'
-        )
-      end
-
-      it 'removes export_path item when blank is submitted' do
-        MaterialExportItem.create!(material:, profile: 'legacy_drive',
-                                   export_path: '素材/remove.png',
-                                   created_by_user: member_user)
-        MaterialVersionRecorder.record!(material:, event_type: :create,
-                                        created_by_user: member_user)
-
-        expect do
-          put "/materials/#{ material.id }", params: {
-            tag: 'material_update_old',
-            export_paths: { legacy_drive: '' }
-          }
-        end.to change(MaterialExportItem, :count).by(-1)
-          .and change(MaterialVersion, :count).by(1)
-
-        expect(response).to have_http_status(:ok)
-        expect(material.reload.material_export_items).to be_empty
-        expect(material.material_versions.order(:version_no).last.export_paths_json).to eq({})
-      end
-
-      it 'rejects sha256-blocked replacement file' do
-        sha256 = Digest::SHA256.hexdigest('blocked-update')
-        MaterialImportBlock.create!(match_kind: 'sha256',
-                                    sha256:,
-                                    reason: 'source_owner_request',
-                                    created_by_user: admin_user)
-
-        put "/materials/#{ material.id }", params: {
-          tag: 'material_update_old',
-          file: dummy_upload(filename: 'blocked.png', body: 'blocked-update')
-        }
-
-        expect(response).to have_http_status(:unprocessable_entity)
-        expect(material.reload.file.blob.filename.to_s).to eq('old.png')
-      end
-    end
-  end
-
-  describe 'GET /materials/download.zip' do
-    let!(:tag_a) { Tag.create!(tag_name: TagName.create!(name: 'zip_a'), category: :material) }
-    let!(:tag_b) { Tag.create!(tag_name: TagName.create!(name: 'zip_b'), category: :material) }
-    let!(:material_a) do
-      build_material(tag: tag_a, user: member_user,
-                     file: dummy_upload(filename: 'a.png', body: 'zip-a'))
-    end
-    let!(:material_b) do
-      build_material(tag: tag_b, user: member_user,
-                     file: dummy_upload(filename: 'b.png', body: 'zip-b'))
-    end
-
-    before do
-      MaterialExportItem.create!(material: material_a, profile: 'legacy_drive',
-                                 export_path: '素材/a.png',
-                                 created_by_user: member_user)
-      MaterialExportItem.create!(material: material_b, profile: 'legacy_drive',
-                                 export_path: '素材/b.png',
-                                 created_by_user: member_user)
-    end
-
-    it 'uses material_export_items.export_path as ZIP entry paths' do
-      get '/materials/download.zip', params: { profile: 'legacy_drive' }
-
-      expect(response).to have_http_status(:ok)
-      expect(response.media_type).to eq('application/zip')
-      expect(response.body.b).to include('素材/a.png'.b)
-      expect(response.body.b).to include('素材/b.png'.b)
-    end
-
-    it 'filters by tag_id' do
-      get '/materials/download.zip', params: { profile: 'legacy_drive', tag_id: tag_a.id }
-
-      expect(response).to have_http_status(:ok)
-      expect(response.body.b).to include('素材/a.png'.b)
-      expect(response.body.b).not_to include('素材/b.png'.b)
-    end
-
-    it 'does not include disabled export items' do
-      material_b.material_export_items.first.update!(enabled: false)
-
-      get '/materials/download.zip', params: { profile: 'legacy_drive' }
-
-      expect(response).to have_http_status(:ok)
-      expect(response.body.b).to include('素材/a.png'.b)
-      expect(response.body.b).not_to include('素材/b.png'.b)
-    end
-  end
-
-  describe 'GET /materials/versions' do
-    let!(:tag) do
-      Tag.create!(tag_name: TagName.create!(name: 'material_history'), category: :material)
-    end
-    let!(:material) do
-      build_material(tag:, user: member_user, file: dummy_upload(filename: 'history.png'))
-    end
-
-    it 'returns material versions in reverse chronological order' do
-      MaterialVersionRecorder.record!(material:, event_type: :create,
-                                      created_by_user: member_user)
-      material.update!(url: 'https://example.com/history')
-      MaterialVersionRecorder.record!(material:, event_type: :update,
-                                      created_by_user: admin_user)
-
-      get '/materials/versions', params: { material_id: material.id }
-
-      expect(response).to have_http_status(:ok)
-      expect(json['count']).to eq(2)
-      versions = json.fetch('versions')
-      expect(versions.map { |v| v['version_no'] }).to eq([2, 1])
-      expect(versions.first).to include(
-        'material_id' => material.id,
-        'event_type' => 'update',
-        'tag_name' => 'material_history',
-        'file_filename' => 'history.png',
-        'url' => 'https://example.com/history'
-      )
-      expect(versions.first['created_by_user']).to include('id' => admin_user.id)
-    end
-
-    it 'filters material versions by tag and event_type' do
-      MaterialVersionRecorder.record!(material:, event_type: :create,
-                                      created_by_user: member_user)
-
-      get '/materials/versions', params: {
-        tag: 'material_history',
-        event_type: 'create'
-      }
-
-      expect(response).to have_http_status(:ok)
-      expect(json.fetch('versions').map { |v| v['material_id'] }).to include(material.id)
-      expect(json.fetch('versions').map { |v| v['event_type'] }).to all(eq('create'))
-    end
-  end
-
-  describe 'material sync suppressions' do
-    it 'requires member permission for index' do
-      sign_out
-
-      get '/materials/suppressions'
-
-      expect(response).to have_http_status(:unauthorized)
-    end
-
-    it 'creates source suppression as member' do
-      sign_in_as(member_user)
-
-      expect do
-        post '/materials/suppressions', params: {
-          source_kind: 'google_drive_path_prefix',
-          drive_path: '伊地知ニジカ/危険素材',
-          reason: 'copyright_high_risk'
-        }
-      end.to change(MaterialSyncSuppression, :count).by(1)
-
-      expect(response).to have_http_status(:created)
-      expect(json).to include(
-        'source_kind' => 'google_drive_path_prefix',
-        'drive_path' => '伊地知ニジカ/危険素材',
-        'normalized_source_key' => 'google_drive_path_prefix:伊地知ニジカ/危険素材'
-      )
     end
   end
 
   describe 'DELETE /materials/:id' do
-    let!(:tag) do
-      Tag.create!(tag_name: TagName.create!(name: 'material_destroy'), category: :material)
-    end
+    let!(:tag) { Tag.create!(tag_name: TagName.create!(name: 'material_destroy'), category: :material) }
     let!(:material) do
       build_material(tag:, user: member_user, file: dummy_upload(filename: 'destroy.png'))
     end

backend/spec/requests/posts_spec.rb

@@ -1,5 +1,4 @@
 require 'rails_helper'
-require 'base64'
 require 'set'
 
 include ActiveSupport::Testing::TimeHelpers
@@ -9,11 +8,6 @@ RSpec.describe 'Posts API', type: :request do
   # resized_thumbnail! が MiniMagick 依存でコケやすいので request spec ではスタブしとくのが無難。
   before do
     allow_any_instance_of(Post).to receive(:resized_thumbnail!).and_return(true)
-    allow(Post).to receive(:resized_thumbnail_attachment).and_return(
-      io: StringIO.new('dummy'),
-      filename: 'resized_thumbnail.jpg',
-      content_type: 'image/jpeg'
-    )
   end
 
   def create_nico_tag!(name)
@@ -25,18 +19,6 @@ RSpec.describe 'Posts API', type: :request do
     Rack::Test::UploadedFile.new(StringIO.new('dummy'), 'image/jpeg', original_filename: 'dummy.jpg')
   end
 
-  def real_thumbnail_upload
-    gif =
-        Base64.decode64(
-            'R0lGODdhAQABAIABAP///wAAACwAAAAAAQABAAACAkQBADs=')
-
-    Rack::Test::UploadedFile.new(
-      StringIO.new(gif),
-      'image/gif',
-      original_filename: 'thumbnail.gif'
-    )
-  end
-
   def post_write_params params = { }
     { parent_post_ids: '' }.merge(params)
   end
@@ -54,7 +36,6 @@ RSpec.describe 'Posts API', type: :request do
             title: post.title,
             url: post.url,
             thumbnail_base: post.thumbnail_base,
-            video_ms: post.video_ms,
             tags: post.snapshot_tag_names.join(' '),
             parent_post_ids: post.snapshot_parent_post_ids.join(' '),
             original_created_from: post.original_created_from,
@@ -146,22 +127,6 @@ RSpec.describe 'Posts API', type: :request do
       expect(all_tag_names).to include("spec_tag")
     end
 
-    it 'keeps children and sections keys in non-detail tag responses' do
-      PostTagSection.create!(post: hit_post, tag:, begin_ms: 1_000, end_ms: nil)
-
-      get '/posts'
-
-      expect(response).to have_http_status(:ok)
-
-      hit_json = json.fetch('posts').find { |post| post['id'] == hit_post.id }
-      tag_json = hit_json.fetch('tags').find { |item| item['name'] == 'spec_tag' }
-
-      expect(tag_json.fetch('children')).to eq([])
-      expect(tag_json.fetch('sections')).to eq([
-        { 'begin_ms' => 1_000, 'end_ms' => nil }
-      ])
-    end
-
     context "when q is provided" do
       it "filters posts by q (hit case)" do
         get "/posts", params: { tags: "spec_tag" }
@@ -552,24 +517,6 @@ RSpec.describe 'Posts API', type: :request do
         expect([true, false]).to include(json['viewed'])
       end
 
-      it 'omits deprecated tags' do
-        deprecated_tag = Tag.create!(
-          name: 'deprecated_post_tag',
-          category: :general,
-          deprecated_at: Time.current
-        )
-        PostTag.create!(post: post_record, tag: deprecated_tag)
-
-        request
-
-        expect(response).to have_http_status(:ok)
-        tag_names = json.fetch('tags').flat_map { |node|
-          [node.fetch('name')] + node.fetch('children').map { |child| child.fetch('name') }
-        }
-        expect(tag_names).to include('spec_tag')
-        expect(tag_names).not_to include('deprecated_post_tag')
-      end
-
       context 'when post has parent, child, and sibling posts' do
         let!(:parent_post) do
           create_parent_post!(
@@ -731,66 +678,6 @@ RSpec.describe 'Posts API', type: :request do
       expect(json['tags'][0]).to have_key('name')
     end
 
-    it '201 when posting manually with a thumbnail' do
-      sign_in_as(member)
-      allow(Post).to receive(:resized_thumbnail_attachment).and_call_original
-
-      post '/posts', params: post_write_params(
-        title: 'thumbnail post',
-        url: 'https://example.com/thumbnail-post',
-        tags: 'spec_tag',
-        thumbnail: real_thumbnail_upload
-      )
-
-      expect(response).to have_http_status(:created)
-      post_record = Post.find(json.fetch('id'))
-      expect(post_record.thumbnail).to be_attached
-      expect(post_record.thumbnail.blob.content_type).to eq('image/jpeg')
-      expect { post_record.thumbnail.download }.not_to raise_error
-    end
-
-    it 'resizes the thumbnail before the create transaction begins' do
-      sign_in_as(member)
-
-      open_transactions = []
-      baseline_open_transactions = Post.connection.open_transactions
-      allow(Post).to receive(:resized_thumbnail_attachment) do |_upload|
-        open_transactions << Post.connection.open_transactions
-        { io: StringIO.new('dummy'),
-          filename: 'resized_thumbnail.jpg',
-          content_type: 'image/jpeg' }
-      end
-
-      post '/posts', params: post_write_params(
-        title: 'transaction post',
-        url: 'https://example.com/transaction-post',
-        tags: 'spec_tag',
-        thumbnail: dummy_upload
-      )
-
-      expect(response).to have_http_status(:created)
-      expect(open_transactions).to eq([baseline_open_transactions])
-    end
-
-    it 'returns 422 and does not create a post when thumbnail resize fails' do
-      sign_in_as(member)
-      allow(Post).to receive(:resized_thumbnail_attachment).and_raise(MiniMagick::Error)
-
-      expect {
-        post '/posts', params: post_write_params(
-          title: 'broken thumbnail post',
-          url: 'https://example.com/broken-thumbnail-post',
-          tags: 'spec_tag',
-          thumbnail: dummy_upload
-        )
-      }.not_to change(Post, :count)
-
-      expect(response).to have_http_status(:unprocessable_entity)
-      expect(json.fetch('errors')).to include(
-        'thumbnail' => ['サムネイル画像の変換に失敗しました．']
-      )
-    end
-
     it '201 and creates post + tags when member and tags have aliases' do
       sign_in_as(member)
 
@@ -810,250 +697,6 @@ RSpec.describe 'Posts API', type: :request do
       expect(names).not_to include('manko')
     end
 
-    it 'rejects a deprecated tag specified directly' do
-      Tag.create!(
-        name: 'deprecated_direct_tag',
-        category: :general,
-        deprecated_at: Time.current
-      )
-      sign_in_as(member)
-
-      post '/posts', params: post_write_params(
-        title: 'new post',
-        url: 'https://example.com/deprecated-direct-tag',
-        tags: 'deprecated_direct_tag',
-        thumbnail: dummy_upload
-      )
-
-      expect(response).to have_http_status(:unprocessable_entity)
-      expect(json.fetch('errors')).to include(
-        'tags' => ['廃止済みタグは付与できません．']
-      )
-    end
-
-    it 'expands through multiple deprecated parent tags and saves active ancestors' do
-      child = Tag.create!(name: 'active_child', category: :general)
-      deprecated_parent = Tag.create!(
-        name: 'deprecated_parent',
-        category: :general,
-        deprecated_at: Time.current
-      )
-      deprecated_grandparent = Tag.create!(
-        name: 'deprecated_grandparent',
-        category: :general,
-        deprecated_at: Time.current
-      )
-      active_grandparent = Tag.create!(name: 'active_grandparent', category: :general)
-      TagImplication.create!(tag: child, parent_tag: deprecated_parent)
-      TagImplication.create!(tag: deprecated_parent, parent_tag: deprecated_grandparent)
-      TagImplication.create!(tag: deprecated_grandparent, parent_tag: active_grandparent)
-      sign_in_as(member)
-
-      post '/posts', params: post_write_params(
-        title: 'expanded post',
-        url: 'https://example.com/expanded-deprecated-parent',
-        tags: 'active_child',
-        thumbnail: dummy_upload
-      )
-
-      expect(response).to have_http_status(:created)
-      saved_names = Post.find(json.fetch('id')).tags.map(&:name)
-      expect(saved_names).to include('active_child', 'active_grandparent')
-      expect(saved_names).not_to include('deprecated_parent', 'deprecated_grandparent')
-    end
-
-    it 'returns validation error for an invalid section literal' do
-      sign_in_as(member)
-
-      post '/posts', params: post_write_params(
-        title: 'invalid section literal',
-        url: 'https://example.com/invalid-section-literal',
-        tags: 'spec_tag[1:aa-2:00]',
-        thumbnail: dummy_upload
-      )
-
-      expect(response).to have_http_status(:unprocessable_entity)
-      expect(json).to include(
-        'type' => 'validation_error',
-        'message' => '入力内容を確認してください．'
-      )
-      expect(json.fetch('errors')).to include(
-        'tags' => ['タグ区間の記法が不正です．']
-      )
-    end
-
-    it 'creates a video post with duration' do
-      sign_in_as(member)
-
-      post '/posts', params: post_write_params(
-        title: 'video post',
-        url: 'https://example.com/video-post',
-        tags: '動画 spec_tag',
-        duration: '3:00.500',
-        thumbnail: dummy_upload
-      )
-
-      expect(response).to have_http_status(:created)
-      expect(Post.find(json.fetch('id')).video_ms).to eq(180_500)
-      expect(json.fetch('video_ms')).to eq(180_500)
-    end
-
-    it 'creates a video post with number input duration seconds' do
-      sign_in_as(member)
-
-      post '/posts', params: post_write_params(
-        title: 'video post seconds',
-        url: 'https://example.com/video-post-seconds',
-        tags: '動画 spec_tag',
-        duration: '180.5',
-        thumbnail: dummy_upload
-      )
-
-      expect(response).to have_http_status(:created)
-      expect(Post.find(json.fetch('id')).video_ms).to eq(180_500)
-      expect(json.fetch('video_ms')).to eq(180_500)
-    end
-
-    it 'clears video_ms when the saved tags do not include 動画' do
-      sign_in_as(member)
-
-      post '/posts', params: post_write_params(
-        title: 'non video post',
-        url: 'https://example.com/non-video-post',
-        tags: 'spec_tag',
-        duration: '3:00',
-        thumbnail: dummy_upload
-      )
-
-      expect(response).to have_http_status(:created)
-      expect(Post.find(json.fetch('id')).video_ms).to be_nil
-    end
-
-    it 'returns validation error when a bounded section exceeds duration' do
-      sign_in_as(member)
-
-      post '/posts', params: post_write_params(
-        title: 'too long section',
-        url: 'https://example.com/too-long-section',
-        tags: '動画 伊地知ニジカ[2:50-3:10]',
-        duration: '3:00',
-        thumbnail: dummy_upload
-      )
-
-      expect(response).to have_http_status(:unprocessable_entity)
-      expect(json.fetch('errors')).to include(
-        'video_ms' => ['タグ区間の終端が動画時間を超えてゐます．']
-      )
-    end
-
-    it 'saves open-ended sections with end_ms NULL' do
-      sign_in_as(member)
-
-      post '/posts', params: post_write_params(
-        title: 'open ended section literal',
-        url: 'https://example.com/open-ended-section-literal',
-        tags: '動画 伊地知ニジカ[1:00-]',
-        duration: '3:00',
-        thumbnail: dummy_upload
-      )
-
-      expect(response).to have_http_status(:created)
-
-      created_post = Post.find(json.fetch('id'))
-      tag = Tag.joins(:tag_name).find_by!(tag_names: { name: '伊地知ニジカ' })
-      section = PostTagSection.find_by!(post: created_post, tag:)
-
-      expect(section.begin_ms).to eq(60_000)
-      expect(section.end_ms).to be_nil
-    end
-
-    it 'does not save sections for [-]' do
-      sign_in_as(member)
-
-      post '/posts', params: post_write_params(
-        title: 'fully open section literal',
-        url: 'https://example.com/fully-open-section-literal',
-        tags: '伊地知ニジカ[-]',
-        thumbnail: dummy_upload
-      )
-
-      expect(response).to have_http_status(:created)
-
-      created_post = Post.find(json.fetch('id'))
-      tag = Tag.joins(:tag_name).find_by!(tag_names: { name: '伊地知ニジカ' })
-      expect(PostTagSection.find_by(post: created_post, tag:)).to be_nil
-    end
-
-    it 'does not save sections for [0:00-]' do
-      sign_in_as(member)
-
-      post '/posts', params: post_write_params(
-        title: 'zero open ended section literal',
-        url: 'https://example.com/zero-open-ended-section-literal',
-        tags: '伊地知ニジカ[0:00-]',
-        thumbnail: dummy_upload
-      )
-
-      expect(response).to have_http_status(:created)
-
-      created_post = Post.find(json.fetch('id'))
-      tag = Tag.joins(:tag_name).find_by!(tag_names: { name: '伊地知ニジカ' })
-      expect(PostTagSection.find_by(post: created_post, tag:)).to be_nil
-    end
-
-    it 'returns end_ms null for open-ended sections in show response' do
-      sign_in_as(member)
-
-      post '/posts', params: post_write_params(
-        title: 'show open ended section literal',
-        url: 'https://example.com/show-open-ended-section-literal',
-        tags: '動画 伊地知ニジカ[1:00-]',
-        duration: '3:00',
-        thumbnail: dummy_upload
-      )
-
-      expect(response).to have_http_status(:created)
-
-      get "/posts/#{ json.fetch('id') }"
-
-      expect(response).to have_http_status(:ok)
-      tag_json = json.fetch('tags').find { |item| item['name'] == '伊地知ニジカ' }
-      expect(tag_json.fetch('sections')).to eq([
-        { 'begin_ms' => 60_000, 'end_ms' => nil }
-      ])
-    end
-
-    it 'allows open-ended sections when begin is within duration' do
-      sign_in_as(member)
-
-      post '/posts', params: post_write_params(
-        title: 'valid open ended section literal',
-        url: 'https://example.com/valid-open-ended-section-literal',
-        tags: '動画 伊地知ニジカ[1:00-]',
-        duration: '3:00',
-        thumbnail: dummy_upload
-      )
-
-      expect(response).to have_http_status(:created)
-    end
-
-    it 'rejects open-ended sections when begin equals duration' do
-      sign_in_as(member)
-
-      post '/posts', params: post_write_params(
-        title: 'invalid open ended section literal',
-        url: 'https://example.com/invalid-open-ended-section-literal',
-        tags: '動画 伊地知ニジカ[3:00-]',
-        duration: '3:00',
-        thumbnail: dummy_upload
-      )
-
-      expect(response).to have_http_status(:unprocessable_entity)
-      expect(json.fetch('errors')).to include(
-        'video_ms' => ['タグ区間の開始が動画時間以上です．']
-      )
-    end
-
     context "when nico tag already exists in tags" do
       before do
         Tag.find_undiscard_or_create_by!(
@@ -1287,26 +930,6 @@ RSpec.describe 'Posts API', type: :request do
       expect(names).to include('spec_tag_2')
     end
 
-    it 'rejects a deprecated tag specified directly' do
-      Tag.create!(
-        name: 'deprecated_update_tag',
-        category: :general,
-        deprecated_at: Time.current
-      )
-      sign_in_as(member)
-
-      put "/posts/#{ post_record.id }", params: post_update_params(
-        post_record,
-        title: 'updated title',
-        tags: 'deprecated_update_tag'
-      )
-
-      expect(response).to have_http_status(:unprocessable_entity)
-      expect(json.fetch('errors')).to include(
-        'tags' => ['廃止済みタグは付与できません．']
-      )
-    end
-
     context "when nico tag already exists in tags" do
       before do
         Tag.find_undiscard_or_create_by!(