#351

AGENTS.md

@@ -12,21 +12,16 @@ BTRC Hub / タグ広場 is a split Rails API and React frontend repository.
 ## Stack
 
 - Backend: Ruby `3.2.2` from `backend/.ruby-version`, Rails `~> 8.0.2`.
-- Backend dependencies include `mysql2`, `sqlite3`, `rspec-rails`,
+- Backend dependencies include `mysql2`, `sqlite3`, `rspec-rails`, `factory_bot_rails`, `rack-cors`, `jwt`, `discard`, `gollum`, `whenever`, `aws-sdk-s3`, `brakeman`, and `rubocop-rails-omakase`.
-  `factory_bot_rails`, `rack-cors`, `jwt`, `discard`, `gollum`, `whenever`,
-  `aws-sdk-s3`, `brakeman`, and `rubocop-rails-omakase`.
 - Frontend: React `^19.1.0`, TypeScript `~5.8.3`, Vite `^6.3.5`.
-- Frontend data/UI dependencies include Axios, TanStack Query, Tailwind CSS,
+- Frontend data/UI dependencies include Axios, TanStack Query, Tailwind CSS, Framer Motion, Radix UI components, lucide-react, MDX/Markdown tooling, and Zustand.
-  Framer Motion, Radix UI components, lucide-react, MDX/Markdown tooling, and
-  Zustand.
 
 ## Main directories
 
 - `backend/app/controllers`: Rails API controllers.
 - `backend/app/models`: Active Record models.
 - `backend/app/representations`: API response representation classes.
-- `backend/app/services`: domain services such as version recording,
+- `backend/app/services`: domain services such as version recording, wiki commit, YouTube sync, and similarity calculation.
-  wiki commit, YouTube sync, and similarity calculation.
 - `backend/config/routes.rb`: API routes.
 - `backend/db/migrate`: migrations.
 - `backend/db/schema.rb`: current schema snapshot.
@@ -89,147 +84,52 @@ cd frontend
 npm run dev
 npm run build
 npm run lint
-npm run test
-npm run test:run
 npm run preview
 ```
 
-`npm run build` runs `tsc -b && vite build`, then `postbuild` runs
+`npm run build` runs `tsc -b && vite build`, then `postbuild` runs `node scripts/generate-sitemap.js`.
-`node scripts/generate-sitemap.js`.
 
-`npm run test` runs Vitest in watch mode. Use `npm run test:run` for a non-watch frontend test run.
+Do not write or report `npm test` as a repository command unless a `test` script is added to `frontend/package.json`.
 
 ## Coding style
 
 - Prefer precise, minimal changes.
 - Do not flatter or over-explain.
 - Explain risks directly.
-- Prefer single quotes for strings unless interpolation or escaping makes
+- Prefer single quotes for strings unless interpolation or escaping makes double quotes better.
-  double quotes better.
 - Ruby: never put a space before method-call parentheses.
-- Ruby: never put a line break immediately before `)`.
 - Ruby: do not use `%w` or `%i`.
-- Ruby hashes are not blocks; keep `}` on the same line as the final pair.
+- TypeScript and Python: use GNU-style spacing before parentheses where syntactically valid.
-- Ruby hashes keep the first pair on the same line as `{` unless line length
-  requires a break.
-- Ruby blocks use separate `{ ... }` rules from hashes, with 2-space body
-  indentation.
-- For arrays, never put whitespace or a line break immediately before `]`.
-- Keep the first element on the same line as `[` by default.
-- If an array would exceed the line limit, break after `[` and indent
-  elements by 4 spaces.
-- TypeScript and Python: use GNU-style spacing before parentheses where
-  syntactically valid.
-- Never write Ruby, TypeScript, or TSX lines longer than 99 characters.
-- Aim to keep Ruby, TypeScript, and TSX lines within 79 characters where practical.
-- 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.
 - 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
+- Inspect existing routes, controllers, models, services, and specs before editing backend behavior.
-  editing backend behavior.
+- For API behavior changes, add or update request specs under `backend/spec/requests`.
-- For API behavior changes, add or update request specs under
+- Prefer RSpec for new backend tests; existing minitest files under `backend/test` do not make minitest the default for new coverage.
-  `backend/spec/requests` only when the user explicitly asks for tests.
-- 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
+- Preserve the `X-Transfer-Code` user identification flow unless the task explicitly changes authentication.
-  explicitly changes authentication.
+- Be careful with version tables, `version_no`, optimistic concurrency, wiki revisions, and restore/diff behavior.
-- Be careful with version tables, `version_no`, optimistic concurrency,
-  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.
 
 ## Frontend rules
 
 - Use `frontend/src/lib/api.ts` for API calls so headers and camelCase conversion stay consistent.
-- Add or reuse TanStack Query keys through `frontend/src/lib/queryKeys.ts`;
+- Add or reuse TanStack Query keys through `frontend/src/lib/queryKeys.ts`; avoid ad hoc query key arrays.
-  avoid ad hoc query key arrays.
 - Encode URL path-segment values with `encodeURIComponent`.
 - React hooks must be called unconditionally.
-- Keep page-level code under `frontend/src/pages` and shared UI/feature code
+- Keep page-level code under `frontend/src/pages` and shared UI/feature code under `frontend/src/components` unless existing patterns point elsewhere.
-  under `frontend/src/components` unless existing patterns point elsewhere.
 - Match existing Tailwind, component, and import alias conventions.
-- 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, prefer modern kana usage and natural current
-  phrasing over historical spellings or awkward literal wording.
-- For user-facing Japanese ellipses, prefer `……` over ASCII `...`.
-
-### Frontend TSX style
-
-- Preserve the local TSX formatting style.
-- Do not normalize TSX to common Prettier-style React formatting unless
-  explicitly asked.
-- 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.
-- A leading tab is exactly equivalent to 8 leading spaces.
-- 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
-  does so.
-- Keep JSX closing parentheses in the existing compact style, for example
-  `</div>)` rather than moving `)` onto a separate line.
-- Do not add braces around `if`, `else`, or `for` bodies when the body is a
-  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`.
-
-Preferred:
-
-```tsx
-const PostFormTagsArea: FC<Props> = ({ tags, setTags, errors, ...rest }) => {
-  return (
-      <TextArea
-	  {...rest}
-	  ref={ref}
-	  value={tags}
-	  invalid={errors && errors.length > 0}
-	  onChange={ev => setTags (ev.target.value)}/>)
-}
-```
-
-Avoid:
-
-```tsx
-function PostFormTagsArea ({ tags, setTags }: Props) {
-  return (
-    <TextArea
-      value={tags}
-      onChange={ev => setTags (ev.target.value)}
-    />
-  )
-}
-```
 
 ## Codex workflow
 
 - First inspect existing patterns; do not invent new architecture when a local convention exists.
 - Keep changes scoped to the requested issue.
-- Do not scan or summarize dependency/generated/runtime directories such as
+- Do not scan or summarize dependency/generated/runtime directories such as `node_modules`, `dist`, `tmp`, `log`, and `storage` unless explicitly needed.
-  `node_modules`, `dist`, `tmp`, `log`, and `storage` unless explicitly needed.
+- Before touching wiki, tag, versioning, BAN, IP BAN, or authentication behavior, inspect the related request specs and service objects.
-- Before touching wiki, tag, versioning, BAN, IP BAN, or authentication
+- If frontend code changes, run the existing frontend verification commands that apply: `npm run build` and `npm run lint`.
-  behavior, inspect the related request specs and service objects.
+- If backend code changes, run the relevant RSpec command; for broad backend changes, run `bundle exec rspec`.
-- 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.
 - If a verification command cannot be run or fails, report the exact command and failure.
 
 ## Completion criteria
@@ -237,8 +137,7 @@ function PostFormTagsArea ({ tags, setTags }: Props) {
 A task is complete only when:
 
 - implementation is complete,
-- relevant non-test verification commands pass, or failures are clearly
+- relevant verification commands pass, or failures are clearly explained,
-  explained,
 - unrelated files are not changed,
 - migrations and schema are consistent when schema changes are made,
 - user-facing behavior is documented when needed.

backend/AGENTS.md

@@ -4,9 +4,7 @@
 
 These rules apply to work under `backend/`.
 
-This is a Rails API app using Active Record, RSpec, request specs,
+This is a Rails API app using Active Record, RSpec, request specs, service objects, representation classes, and version tables for post/tag/wiki history.
-service objects, representation classes, and version tables for post/tag/wiki
-history.
 
 ## Commands
 
@@ -47,66 +45,37 @@ 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.
 - `app/models`: Active Record models and concerns.
 - `app/representations`: JSON response shaping.
-- `app/services`: domain services such as version recorders, wiki commit,
+- `app/services`: domain services such as version recorders, wiki commit, YouTube sync, and similarity calculation.
-  YouTube sync, and similarity calculation.
 - `config/routes.rb`: public API routes.
 - `db/migrate`: migrations.
 - `db/schema.rb`: schema snapshot.
 - `lib/tasks`: custom Rake tasks.
 - `spec`: RSpec tests.
 
-Before changing behavior, inspect the matching route, controller, model,
+Before changing behavior, inspect the matching route, controller, model, service, representation, and spec.
-service, representation, and spec.
 
 ## Ruby style
 
 - 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.
-- 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.
-- 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.
-- 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
-  dense.
-- For Ruby arrays, never put whitespace or a line break immediately before `]`.
-- Keep the first element on the same line as `[` by default.
-- If an array would exceed the line limit, break after `[` and indent
-  elements by 4 spaces.
-- For Ruby blocks, use 2-space indentation for the block body.
 - Keep comments short and useful; avoid narrating obvious code.
 - Do not add production dependencies without approval.
 
 ## Authentication and authorization
 
-- Authentication is handled through the `X-Transfer-Code` header in
+- Authentication is handled through the `X-Transfer-Code` header in `ApplicationController#authenticate_user`.
-  `ApplicationController#authenticate_user`.
 - `current_user` is set by looking up `User.inheritance_code`.
-- Do not bypass or weaken the `X-Transfer-Code` flow unless the task
+- Do not bypass or weaken the `X-Transfer-Code` flow unless the task explicitly changes authentication.
-  explicitly changes authentication.
+- Unauthenticated write actions should return `:unauthorized` consistently with existing controllers.
-- Unauthenticated write actions should return `:unauthorized` consistently
-  with existing controllers.
 - Role checks use `User` enum roles: `guest`, `member`, and `admin`.
-- Use `current_user.gte_member?` for member-or-admin write permissions where
+- Use `current_user.gte_member?` for member-or-admin write permissions where existing controllers do so.
-  existing controllers do so.
 - Use `current_user.admin?` only for admin-only paths, such as tag child relationship changes.
 - Do not replace role checks with looser presence checks.
 
@@ -119,9 +88,7 @@ service, representation, and spec.
 - User and IP bans use `banned_at`, not a boolean `banned` column.
 - `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
+- If changing request authentication or controller before actions, add or update request specs covering banned users and banned IP addresses.
-  update request specs covering banned users and banned IP addresses only when
-  the user explicitly asks for tests.
 
 ## RSpec
 
@@ -132,88 +99,49 @@ service, representation, and spec.
 - Put Rake task coverage under `spec/tasks`.
 - `spec/rails_helper.rb` loads `spec/support/**/*.rb`.
 - Request specs include `AuthHelper` and `JsonHelper`.
-- `AuthHelper#sign_in_as(user)` stubs
+- `AuthHelper#sign_in_as(user)` stubs `ApplicationController#current_user`; use it when matching existing request spec style.
-  `ApplicationController#current_user`; use it when matching existing
+- Add or update request specs for API behavior changes, especially status codes, permissions, response shape, and version conflict behavior.
-  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.
 
 ## Migrations
 
 - Keep migrations and `db/schema.rb` consistent.
 - Use reversible migrations where practical; otherwise define explicit `up` and `down`.
-- For data backfills inside migrations, follow the existing pattern of
+- For data backfills inside migrations, follow the existing pattern of defining migration-local `ActiveRecord::Base` classes with `self.table_name`.
-  defining migration-local `ActiveRecord::Base` classes with
-  `self.table_name`.
 - Preserve existing indexes, foreign keys, check constraints, and null constraints.
 - Be careful with MySQL-specific options already present in migrations, such as `after:`.
-- Do not edit old migrations just to change current behavior unless
+- Do not edit old migrations just to change current behavior unless explicitly requested; add a new migration.
-  explicitly requested; add a new migration.
 
 ## Version tables
 
 - Versioned records include posts, tags, nico tags, and wiki pages.
-- Current records have `version_no`; version tables have positive
+- Current records have `version_no`; version tables have positive `version_no` with unique indexes scoped to the parent record.
-  `version_no` with unique indexes scoped to the parent record.
 - Version event types are `create`, `update`, `discard`, and `restore`.
 - Version rows are readonly through the `VersionRecord` concern.
-- Use the existing recorder services instead of manually inserting version
+- Use the existing recorder services instead of manually inserting version rows in application code:
-  rows in application code:
   - `PostVersionRecorder`
   - `TagVersionRecorder`
   - `NicoTagVersionRecorder`
   - `WikiVersionRecorder`
   - `TagVersioning`
-- `VersionRecorder` locks the current record, validates sequence consistency,
+- `VersionRecorder` locks the current record, validates sequence consistency, skips unchanged update snapshots, creates the next version row, and updates the record `version_no`.
-  skips unchanged update snapshots, creates the next version row, and updates
-  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
+- For optimistic concurrency paths, preserve `base_version_no`, `force`, and `merge` semantics and cover conflicts in request specs.
-  `merge` semantics. Cover conflicts in request specs only when the user
-  explicitly asks for tests.
 
 ## Domain cautions
 
-- Posts have tag snapshots, parent post implications, original-created ranges,
+- Posts have tag snapshots, parent post implications, original-created ranges, viewed state, and version conflict behavior.
-  viewed state, and version conflict behavior.
+- Tags have canonical names, aliases through `TagName`, categories, parent implications, discard behavior, and version snapshots.
-- Tags have canonical names, aliases through `TagName`, categories, parent
+- Nico tags have separate relation/version behavior; do not treat them like normal editable tags without checking existing code.
-  implications, discard behavior, and version snapshots.
+- Wiki pages involve page content, revisions/history, version rows, title/tag-name behavior, and diff/restore paths.
-- Nico tags have separate relation/version behavior; do not treat them like
+- Materials, theatres, and comments have user and permission checks; inspect the controller before changing them.
-  normal editable tags without checking existing code.
-- Wiki pages involve page content, revisions/history, version rows,
-  title/tag-name behavior, and diff/restore paths.
-- Materials, theatres, and comments have user and permission checks; inspect
-  the controller before changing them.
 
 ## API responses
 
 - Use representation classes under `app/representations` when existing endpoints do.
-- Keep response keys consistent with existing JSON contracts.
+- Keep response keys consistent with existing JSON contracts; frontend code expects camelCase conversion client-side, while Rails params and JSON keys are generally snake_case.
-- Frontend code expects camelCase conversion client-side, while Rails params
+- Preserve existing HTTP status conventions: `:unauthorized` for no user, `:forbidden` for insufficient role or banned user, `:not_found` for missing records, and `:unprocessable_entity` for validation failures.
-  and JSON keys are generally snake_case.
-- Preserve existing HTTP status conventions:
-  `:unauthorized` for no user, `:forbidden` for insufficient role or banned
-  user, `:not_found` for missing records, and `:unprocessable_entity` for
-  validation failures.
-- For diagnostic or internal helper JSON, prefer a deliberately light response
-  shape over full representation classes when callers only need identifiers,
-  labels, URLs, or weights.
-
-## Active Record performance
-
-- When a controller action serializes nested associations, preload the
-  associations it will touch instead of allowing N+1 queries.
-- Be sensitive to N+1 queries in all backend work.
-- Avoid introducing N+1 queries, and proactively fix existing N+1 issues when
-  you find them in the code path you are editing.
-- When an association may already be preloaded, prefer loaded-association
-  checks that reuse the preloaded data without losing the efficient database
-  path.
 
 ## Files to avoid in routine work
 
-- Do not inspect or edit `tmp/`, `log/`, `storage/`, `vendor/`, or dependency
+- Do not inspect or edit `tmp/`, `log/`, `storage/`, `vendor/`, or dependency directories unless explicitly needed.
-  directories unless explicitly needed.
+- Do not modify generated schema or migration output without the corresponding migration when schema changes are made.
-- Do not modify generated schema or migration output without the corresponding
-  migration when schema changes are made.

backend/Gemfile

@@ -69,5 +69,3 @@ gem 'discard'
 gem "rspec-rails", "~> 8.0", :groups => [:development, :test]
 
 gem 'aws-sdk-s3', require: false
-
-gem 'rails-i18n', '~> 8.0.0'

backend/Gemfile.lock

@@ -306,9 +306,6 @@ GEM
     rails-html-sanitizer (1.6.2)
       loofah (~> 2.21)
       nokogiri (>= 1.15.7, != 1.16.7, != 1.16.6, != 1.16.5, != 1.16.4, != 1.16.3, != 1.16.2, != 1.16.1, != 1.16.0.rc1, != 1.16.0)
-    rails-i18n (8.0.2)
-      i18n (>= 0.7, < 2)
-      railties (>= 8.0.0, < 9)
     railties (8.0.2)
       actionpack (= 8.0.2)
       activesupport (= 8.0.2)
@@ -480,7 +477,6 @@ DEPENDENCIES
   puma (>= 5.0)
   rack-cors
   rails (~> 8.0.2)
-  rails-i18n (~> 8.0.0)
   rspec-rails (~> 8.0)
   rubocop-rails-omakase
   sprockets-rails

backend/app/controllers/application_controller.rb

@@ -1,7 +1,4 @@
 class ApplicationController < ActionController::API
-  rescue_from ActiveRecord::RecordInvalid, with: :render_record_invalid
-  rescue_from ActiveRecord::RecordNotUnique, with: :render_record_not_unique
-
   before_action :reject_banned_ip_address!
   before_action :authenticate_user
   before_action :reject_banned_user!
@@ -28,27 +25,6 @@ class ApplicationController < ActionController::API
     end
   end
 
-  def render_bad_request message = 'リクエストが不正です．'
-    render json: { type: 'bad_request',
-                   message:,
-                   errors: { },
-                   base_errors: [message] },
-           status: :bad_request
-  end
-
-  def render_unprocessable_entity message = '入力を確認してください．', field: nil
-    render_validation_error(fields: field ? { field => [message] } : { },
-                            base: field ? [] : [message])
-  end
-
-  def render_record_invalid error
-    render_validation_error error.record
-  end
-
-  def render_record_not_unique _error = nil
-    render_validation_error base: ['すでに存在してゐます．']
-  end
-
   def reject_banned_ip_address!
     ip_address = IpAddress.find_by(ip_address: IPAddr.new(request.remote_ip).hton)
     return unless ip_address&.banned?
@@ -61,28 +37,4 @@ class ApplicationController < ActionController::API
 
     head :forbidden
   end
-
-  def render_validation_error record = nil, fields: { }, base: [], status: :unprocessable_entity
-    errors = { }
-
-    if record
-      record.errors.each do |error|
-        errors[error.attribute] ||= []
-        errors[error.attribute] << error.message
-      end
-    end
-
-    fields.each do |attr, messages|
-      errors[attr.to_sym] ||= []
-      errors[attr.to_sym].concat(Array(messages))
-    end
-
-    base_errors = Array(base) + Array(errors.delete(:base))
-
-    render json: { type: 'validation_error',
-                   message: '入力内容を確認してください．',
-                   errors:,
-                   base_errors: },
-           status:
-  end
 end

backend/app/controllers/deerjikists_controller.rb

@@ -2,8 +2,7 @@ class DeerjikistsController < ApplicationController
   def show
     platform = params[:platform].to_s.strip
     code = params[:code].to_s.strip
-    return render_bad_request('platform は必須です．') if platform.blank?
+    return head :bad_request if platform.blank? || code.blank?
-    return render_bad_request('code は必須です．') if code.blank?
 
     deerjikist = Deerjikist
                  .joins(:tag)
@@ -23,9 +22,7 @@ class DeerjikistsController < ApplicationController
     platform = params[:platform].to_s.strip
     code = params[:code].to_s.strip
     tag_id = params[:tag_id].to_i
-    return render_bad_request('platform は必須です．') if platform.blank?
+    return head :bad_request if platform.blank? || code.blank? || tag_id <= 0
-    return render_bad_request('code は必須です．') if code.blank?
-    return render_bad_request('tag_id が不正です．') if tag_id <= 0
 
     deerjikist = Deerjikist.find_or_initialize_by(platform:, code:).tap do |d|
       d.tag_id = tag_id
@@ -41,8 +38,7 @@ class DeerjikistsController < ApplicationController
 
     platform = params[:platform].to_s.strip
     code = params[:code].to_s.strip
-    return render_bad_request('platform は必須です．') if platform.blank?
+    return head :bad_request if platform.blank? || code.blank?
-    return render_bad_request('code は必須です．') if code.blank?
 
     Deerjikist.find([platform, code]).destroy!
 

backend/app/controllers/gekanator_games_controller.rb

@@ -1,148 +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.save
-      render json: { id: game.id }, status: :created
-    else
-      render json: { errors: game.errors.full_messages }, status: :unprocessable_entity
-    end
-  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 = weighted_sample_questions(
-        questions,
-        post_id: game.correct_post_id,
-        limit: 2)
-
-    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 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
-end

backend/app/controllers/gekanator_posts_controller.rb

@@ -1,44 +0,0 @@
-class GekanatorPostsController < ApplicationController
-  def index
-    posts =
-        Post
-        .preload(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'))
-
-    render json: { posts: posts.map { |post| post_json(post) } }
-  end
-
-  private
-
-  def post_json post
-    {
-      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,
-      tags: post.tags.map { |tag| tag_json(tag) }
-    }
-  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

@@ -1,56 +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
-
-    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
-end

backend/app/controllers/gekanator_questions_controller.rb

@@ -1,102 +0,0 @@
-class GekanatorQuestionsController < ApplicationController
-  def index
-    questions =
-        GekanatorQuestion
-        .accepted
-        .includes(:gekanator_question_examples)
-        .order(priority_weight: :desc, id: :asc)
-
-    render json: {
-      questions: questions.map { |question| question_json(question) }
-    }
-  end
-
-  private
-
-  def question_json question
-    condition = condition_json(question.condition).deep_symbolize_keys
-    json = {
-      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'
-      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
-end

backend/app/controllers/materials_controller.rb

@@ -40,11 +40,7 @@ class MaterialsController < ApplicationController
     tag_name_raw = params[:tag].to_s.strip
     file = params[: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?
+    return head :bad_request if tag_name_raw.blank? || (file.blank? && url.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
 
     tag_name = TagName.find_undiscard_or_create_by!(name: tag_name_raw)
     tag = tag_name.tag
@@ -58,7 +54,7 @@ class MaterialsController < ApplicationController
     if material.save
       render json: MaterialRepr.base(material, host: request.base_url), status: :created
     else
-      render_validation_error material
+      render json: { errors: material.errors.full_messages }, status: :unprocessable_entity
     end
   end
 
@@ -72,11 +68,7 @@ class MaterialsController < ApplicationController
     tag_name_raw = params[:tag].to_s.strip
     file = params[: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?
+    return head :bad_request if tag_name_raw.blank? || (file.blank? && url.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
 
     tag_name = TagName.find_undiscard_or_create_by!(name: tag_name_raw)
     tag = tag_name.tag
@@ -92,7 +84,7 @@ class MaterialsController < ApplicationController
     if material.save
       render json: MaterialRepr.base(material, host: request.base_url)
     else
-      render_validation_error material
+      render json: { errors: material.errors.full_messages }, status: :unprocessable_entity
     end
   end
 

backend/app/controllers/nico_tags_controller.rb

@@ -1,69 +1,26 @@
 class NicoTagsController < ApplicationController
   def index
-    name = params[:name].presence
+    limit = (params[:limit] || 20).to_i
-    linked_tag = params[:linked_tag].presence
+    cursor = params[:cursor].presence
-    link_status = params[:link_status].presence
-    order = params[:order].to_s.split(':', 2).map(&:strip)
-    order[0] = 'updated_at' unless order[0].in?(['name', 'created_at', 'updated_at'])
-    unless order[1].in?(['asc', 'desc'])
-      order[1] = order[0] == 'name' ? 'asc' : 'desc'
-    end
-    page = (params[:page].presence || 1).to_i
-    limit = (params[:limit].presence || 20).to_i
-
-    page = 1 if page < 1
-    limit = 1 if limit < 1
-
-    post_tag_max_sql =
-        PostTag
-        .select('tag_id, MAX(created_at) AS max_created_at')
-        .group('tag_id')
-        .to_sql
 
     q = Tag.nico_tags
-           .joins(:tag_name)
-           .joins("LEFT JOIN (#{ post_tag_max_sql }) post_tag_max " \
-                  'ON post_tag_max.tag_id = tags.id')
            .includes(:tag_name, tag_name: :wiki_page, linked_tags: { tag_name: :wiki_page })
-    q = q.where('tag_names.name LIKE ?', "%#{ name }%") if name
+           .order(updated_at: :desc)
-    if linked_tag
+    q = q.where('tags.updated_at < ?', Time.iso8601(cursor)) if cursor
-      linked_tag_ids =
-        Tag
-        .joins(:tag_name)
-        .where('tag_names.name LIKE ?', "%#{ linked_tag }%")
-        .pluck(:id)
-      linked_nico_tag_ids = NicoTagRelation.where(tag_id: linked_tag_ids).pluck(:nico_tag_id)
-      q = q.where(id: linked_nico_tag_ids)
-    end
-    if link_status.in?(['linked', 'unlinked'])
-      exists_sql =
-          'EXISTS (SELECT 1 FROM nico_tag_relations ' \
-          'WHERE nico_tag_relations.nico_tag_id = tags.id)'
-      q = link_status == 'linked' ? q.where(exists_sql) : q.where("NOT #{ exists_sql }")
-    end
 
-    count = q.count
+    tags = q.limit(limit + 1).to_a
-    sort_sql =
+
-        case order[0]
+    next_cursor = nil
-        when 'name'
+    if tags.size > limit
-          'tag_names.name'
+      next_cursor = tags.last.updated_at.iso8601(6)
-        when 'updated_at'
+      tags = tags.first(limit)
-          'post_tag_max.max_created_at'
+    end
-        else
-          "tags.#{ order[0] }"
-        end
-    tags = q.reselect('tags.*',
-                      Arel.sql('post_tag_max.max_created_at AS recent_post_tag_created_at'))
-            .order(Arel.sql("#{ sort_sql } #{ order[1] }, tags.id #{ order[1] }"))
-            .limit(limit)
-            .offset((page - 1) * limit)
-            .to_a
 
     render json: { tags: tags.map { |tag|
-      TagRepr.base(tag).merge(
+      TagRepr.base(tag).merge(linked_tags: tag.linked_tags.map { |lt|
-          recent_post_tag_created_at: tag.recent_post_tag_created_at,
+        TagRepr.base(lt)
-          linked_tags: tag.linked_tags.map { |lt| TagRepr.base(lt) })
+      })
-    }, count: }
+    }, next_cursor: }
   end
 
   def update
@@ -73,18 +30,14 @@ class NicoTagsController < ApplicationController
     id = params[:id].to_i
 
     tag = Tag.find(id)
-    return render_bad_request('ニコニコ・タグを指定してください．') unless tag.nico?
+    return head :bad_request unless tag.nico?
 
     linked_tag_names = params[:tags].to_s.split
-    linked_tags = nil
+    linked_tags = Tag.normalise_tags!(linked_tag_names, with_tagme: false,
+                                                        with_no_deerjikist: false)
+    return head :bad_request if linked_tags.any? { |t| t.nico? }
 
     ApplicationRecord.transaction do
-      linked_tags = Tag.normalise_tags!(linked_tag_names, with_tagme: false,
-                                                          with_no_deerjikist: false)
-      if linked_tags.any? { |t| t.nico? }
-        raise Tag::NicoTagNormalisationError
-      end
-
       TagVersioning.record_tag_snapshots!(linked_tags, created_by_user: current_user)
 
       tag.linked_tags = linked_tags
@@ -94,21 +47,5 @@ class NicoTagsController < ApplicationController
     end
 
     render json: tag.linked_tags.map { |t| TagRepr.base(t) }, status: :ok
-  rescue Tag::NicoTagNormalisationError
-    render_validation_error fields: { tags: ['ニコニコ・タグ同士は連携できません．'] }
-  rescue ActiveRecord::RecordInvalid => e
-    render_nico_tag_form_record_invalid e.record
-  end
-
-  private
-
-  def render_nico_tag_form_record_invalid record
-    if record.is_a?(TagName) || record.is_a?(Tag)
-      render_validation_error fields: { tags: record.errors.full_messages.map { |message|
-        "タグ名 “#{ record.name }”: #{ message }"
-      } }
-    else
-      render_validation_error record
-    end
   end
 end

backend/app/controllers/posts_controller.rb

@@ -44,8 +44,7 @@ class PostsController < ApplicationController
         filtered_posts
         .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,
+        .preload(tags: [: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
@@ -96,36 +95,22 @@ class PostsController < ApplicationController
   end
 
   def random
-    post = filtered_posts.preload(:uploaded_user, :parents, :children,
+    post = filtered_posts
-                                  tags: [:deerjikists, :materials, { tag_name: :wiki_page }])
+           .preload(tags: [:deerjikists, :materials, { tag_name: :wiki_page }])
-                         .with_attached_thumbnail
+           .order('RAND()')
-                         .order('RAND()')
+           .first
-                         .first
     return head :not_found unless post
 
     render json: PostRepr.base(post, current_user)
   end
 
   def show
-    post =
+    post = Post.includes(tags: [:deerjikists, :materials, { tag_name: :wiki_page }]).find_by(id: params[:id])
-        Post
-        .includes(:uploaded_user, :parents, :children,
-                  tags: [:deerjikists, :materials, { tag_name: :wiki_page }])
-        .with_attached_thumbnail
-        .find_by(id: params[:id])
     return head :not_found unless post
 
-    parent_posts = post.parents.with_attached_thumbnail.order(:id).to_a
+    render json: PostRepr.base(post, current_user)
-    child_posts = post.children.with_attached_thumbnail.order(:id).to_a
+                         .merge(tags: build_tag_tree_for(post),
-    sibling_posts = sibling_posts_by_parent(parent_posts.map(&:id))
+                                related: PostRepr.many(post.related(limit: 20)))
-    related = post.related(limit: 20).to_a
-
-    render json: PostRepr.detail(post, current_user,
-                                 parent_posts:,
-                                 child_posts:,
-                                 sibling_posts:,
-                                 related:)
-                         .merge(tags: build_tag_tree_for(post.tags))
   end
 
   def create
@@ -148,11 +133,11 @@ class PostsController < ApplicationController
     ApplicationRecord.transaction do
       post.save!
 
-      tags = Tag.normalise_tags!(tag_names)
+      Tag.normalise_tags!(tag_names, with_sections: true) => { tags:, sections: }
       TagVersioning.record_tag_snapshots!(tags, created_by_user: current_user)
 
       tags = Tag.expand_parent_tags(tags)
-      sync_post_tags!(post, tags)
+      sync_post_tags!(post, tags, sections)
 
       sync_parent_posts!(post, parent_post_ids)
 
@@ -164,11 +149,11 @@ class PostsController < ApplicationController
     post.reload
     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．' }
+    head :bad_request
   rescue ArgumentError => e
-    render_validation_error fields: { parent_post_ids: [e.message] }
+    render json: { errors: [e.message] }, status: :unprocessable_entity
   rescue ActiveRecord::RecordInvalid => e
-    render_post_form_record_invalid e.record
+    render json: { errors: e.record.errors.full_messages }, status: :unprocessable_entity
   end
 
   def viewed
@@ -191,10 +176,10 @@ class PostsController < ApplicationController
 
     force = bool?(:force)
     merge = bool?(:merge)
-    return render_bad_request('force と merge は同時に指定できません．') if force && merge
+    return head :bad_request if force && merge
 
     base_version_no = parse_base_version_no
-    return render_bad_request('base_version_no は必須です．') if !(force) && !(base_version_no)
+    return head :bad_request if !(force) && !(base_version_no)
 
     title = params[:title].presence
     tag_names = params[:tags].to_s.split
@@ -251,14 +236,14 @@ class PostsController < ApplicationController
 
     post.reload
     json = PostRepr.base(post, current_user)
-    json['tags'] = build_tag_tree_for(post.tags)
+    json['tags'] = build_tag_tree_for(post)
     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．'] }
+    head :bad_request
   rescue ArgumentError => e
-    render_validation_error fields: { parent_post_ids: [e.message] }
+    render json: { errors: [e.message] }, status: :unprocessable_entity
   rescue ActiveRecord::RecordInvalid => e
-    render_post_form_record_invalid e.record
+    render json: { errors: e.record.errors.full_messages }, status: :unprocessable_entity
   end
 
   def changes
@@ -353,7 +338,7 @@ 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
+  def sync_post_tags! post, desired_tags, sections
     desired_tags.each do |t|
       t.save! if t.new_record?
     end
@@ -372,13 +357,20 @@ 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 tags
+  def build_tag_tree_for post
-    tags = tags.to_a
+    tags = post.tags.to_a
     tag_ids = tags.map(&:id)
 
     implications = TagImplication.where(parent_tag_id: tag_ids, tag_id: tag_ids)
@@ -400,8 +392,11 @@ class PostsController < ApplicationController
       tag = tags_by_id[tag_id]
       return nil unless tag
 
+      sections = PostTagSection.where(post_id: post.id, tag_id:)
+                 .as_json(only: [:begin_ms, :end_ms])
+
       if path.include?(tag_id)
-        return TagRepr.inline(tag).merge(children: [])
+        return TagRepr.base(tag).merge(children: [], sections:)
       end
 
       if memo.key?(tag_id)
@@ -413,32 +408,18 @@ class PostsController < ApplicationController
 
       children = child_ids.filter_map { |cid| build_node.(cid, new_path) }
 
-      memo[tag_id] = TagRepr.inline(tag).merge(children:)
+      memo[tag_id] = TagRepr.base(tag).merge(children:, sections:)
     end
 
     root_ids.filter_map { |id| build_node.call(id, []) }
   end
 
-  def sibling_posts_by_parent parent_post_ids
-    return { } if parent_post_ids.blank?
-
-    implications =
-        PostImplication
-        .where(parent_post_id: parent_post_ids)
-        .includes(post: { thumbnail_attachment: :blob })
-        .order(:parent_post_id, :post_id)
-
-    implications.group_by(&:parent_post_id).transform_values { |items|
-      items.map(&:post)
-    }
-  end
-
   def parse_parent_post_ids
     raise ArgumentError, 'parent_post_ids は必須です．' unless params.key?(:parent_post_ids)
 
     params[:parent_post_ids].to_s.split.map { |token|
       id = Integer(token, exception: false)
-      raise ArgumentError, "親投稿 Id. が不正です: #{ token }" if id.nil? || id <= 0
+      raise ArgumentError, "親投稿 Id. が不正です: #{ token }" if !(id) || id <= 0
 
       id
     }.uniq
@@ -446,7 +427,7 @@ class PostsController < ApplicationController
 
   def sync_parent_posts! post, parent_post_ids
     if parent_post_ids.include?(post.id)
-      post.errors.add :parent_post_ids, '自分自身を親投稿にはできません．'
+      post.errors.add(:base, '自分自身を親投稿にはできません．')
       raise ActiveRecord::RecordInvalid, post
     end
 
@@ -454,8 +435,7 @@ class PostsController < ApplicationController
     missing_ids = parent_post_ids - existing_ids
 
     if missing_ids.present?
-      post.errors.add :parent_post_ids,
+      post.errors.add(:base, "存在しない親投稿 ID があります: #{ missing_ids.join(' ') }")
-                      "存在しない親投稿 Id. があります: #{ missing_ids.join(' ') }"
       raise ActiveRecord::RecordInvalid, post
     end
 
@@ -501,7 +481,21 @@ class PostsController < ApplicationController
   end
 
   def editable_tag_names_from_post post
-    post.tags.not_nico.joins(:tag_name).order('tag_names.name').pluck('tag_names.name')
+    post
+        .post_tags
+        .kept
+        .joins(tag: :tag_name)
+        .merge(Tag.not_nico)
+        .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 post_incoming_snapshot title:, original_created_from:, original_created_before:,
@@ -533,9 +527,16 @@ class PostsController < ApplicationController
   end
 
   def incoming_tag_names_for_snapshot raw_tag_names
-    tags = Tag.normalise_tags!(raw_tag_names, with_tagme: false)
+    Tag.normalise_tags!(raw_tag_names, with_tagme: false, with_sections: true) =>
+        { tags:, sections: }
 
-    Tag.expand_parent_tags(tags).map(&:name).uniq.sort
+    Tag.expand_parent_tags(tags).uniq(&:id).map { |tag|
+      "#{ tag.name }#{ sections[tag.id].to_a.map { section_literal(_1) }.join }"
+    }.sort
+  end
+
+  def section_literal section
+    "[#{ Post.ms_to_time(section[0]) }-#{ Post.ms_to_time(section[1]) }]"
   end
 
   def post_conflict_json post:, base_version_no:, base_snapshot:,
@@ -622,7 +623,8 @@ class PostsController < ApplicationController
                  original_created_from: snapshot[:original_created_from],
                  original_created_before: snapshot[:original_created_before])
 
-    editable_tags = Tag.normalise_tags!(snapshot[:tag_names], with_tagme: false)
+    Tag.normalise_tags!(snapshot[:tag_names], with_tagme: false, with_sections: true) =>
+        { tags: editable_tags, sections: }
     TagVersioning.record_tag_snapshots!(editable_tags, created_by_user: current_user)
 
     readonly_tags = post.tags.nico.to_a
@@ -630,7 +632,7 @@ class PostsController < ApplicationController
     tags = readonly_tags + editable_tags
     tags = Tag.expand_parent_tags(tags)
 
-    sync_post_tags!(post, tags)
+    sync_post_tags!(post, tags, sections)
     sync_parent_posts!(post, snapshot[:parent_post_ids])
 
     PostVersionRecorder.record!(post:, event_type: :update, created_by_user: current_user)
@@ -671,14 +673,4 @@ class PostsController < ApplicationController
 
     merged.uniq.sort
   end
-
-  def render_post_form_record_invalid record
-    if record.is_a?(TagName) || record.is_a?(Tag)
-      render_validation_error fields: { tags: record.errors.full_messages.map { |message|
-        "タグ名 “#{ record.name }”: #{ message }"
-      } }
-    else
-      render_validation_error record
-    end
-  end
 end

backend/app/controllers/preview_controller.rb

@@ -4,7 +4,7 @@ class PreviewController < ApplicationController
     return head :unauthorized unless current_user
 
     url = params[:url]
-    return render_bad_request('URL は必須です．') unless url.present?
+    return head :bad_request unless url.present?
 
     unless url.start_with?(/http(s)?:\/\//)
       url = 'http://' + url
@@ -16,7 +16,7 @@ class PreviewController < ApplicationController
 
     render json: { title: title }
   rescue => e
-    render_bad_request(e.message)
+    render json: { error: e.message }, status: :bad_request
   end
 
   def thumbnail
@@ -25,7 +25,7 @@ class PreviewController < ApplicationController
     return head :unauthorized unless current_user
 
     url = params[:url]
-    return render_bad_request('URL は必須です．') if url.blank?
+    return head :bad_request if url.blank?
 
     unless url.start_with?(/http(s)?:\/\//)
       url = 'http://' + url
@@ -40,11 +40,7 @@ class PreviewController < ApplicationController
       File.delete(path) rescue nil
       send_file image.path, type: 'image/png', disposition: 'inline'
     else
-      render json: { type: 'internal_server_error',
+      render json: { error: 'Failed to generate thumbnail' }, status: :internal_server_error
-                     message: 'サムネールを生成できませんでした．',
-                     errors: { },
-                     base_errors: ['サムネールを生成できませんでした．'] },
-             status: :internal_server_error
     end
   end
 end

backend/app/controllers/tag_children_controller.rb

@@ -5,12 +5,11 @@ class TagChildrenController < ApplicationController
 
     parent_id = params[:parent_id]
     child_id = params[:child_id]
-    return render_bad_request('parent_id は必須です．') if parent_id.blank?
+    return head :bad_request if parent_id.blank? || child_id.blank?
-    return render_bad_request('child_id は必須です．') if child_id.blank?
 
     parent = Tag.find(parent_id)
     child = Tag.find(child_id)
-    return render_bad_request('ニコニコ・タグの階層は変更できません．') if parent.nico? || child.nico?
+    return head :bad_request if parent.nico? || child.nico?
 
     ApplicationRecord.transaction do
       TagVersioning.ensure_snapshot!(child, created_by_user: current_user)
@@ -28,12 +27,11 @@ class TagChildrenController < ApplicationController
 
     parent_id = params[:parent_id]
     child_id = params[:child_id]
-    return render_bad_request('parent_id は必須です．') if parent_id.blank?
+    return head :bad_request if parent_id.blank? || child_id.blank?
-    return render_bad_request('child_id は必須です．') if child_id.blank?
 
     parent = Tag.find(parent_id)
     child = Tag.find(child_id)
-    return render_bad_request('ニコニコ・タグの階層は変更できません．') if parent.nico? || child.nico?
+    return head :bad_request if parent.nico? || child.nico?
 
     ApplicationRecord.transaction do
       TagVersioning.ensure_snapshot!(child, created_by_user: current_user)

backend/app/controllers/tags_controller.rb

@@ -168,7 +168,7 @@ class TagsController < ApplicationController
 
   def show_by_name
     name = params[:name].to_s.strip
-    return render_bad_request('name は必須です．') if name.blank?
+    return head :bad_request if name.blank?
 
     tag = Tag.joins(:tag_name)
              .includes(:tag_name, :materials, tag_name: :wiki_page)
@@ -192,7 +192,7 @@ class TagsController < ApplicationController
 
   def deerjikists_by_name
     name = params[:name].to_s.strip
-    return render_bad_request('name は必須です．') if name.blank?
+    return head :bad_request if name.blank?
 
     tag = Tag.joins(:tag_name)
              .includes(:tag_name, tag_name: :wiki_page)
@@ -214,24 +214,21 @@ class TagsController < ApplicationController
 
     ApplicationRecord.transaction do
       tag.deerjikists = []
-      params[:_json].each.with_index do |item, i|
+      params[:_json].each do
-        platform = item[:platform]
+        platform = _1[:platform]
-        code = normalise_deerjikist_code(platform, item[:code])
+        code = normalise_deerjikist_code(platform, _1[:code])
         deerjikist = Deerjikist.find_or_initialize_by(platform:, code:)
         deerjikist.tag = tag
-        render_deerjikist_form_record_invalid(deerjikist, i) unless deerjikist.save
+        deerjikist.save!
-        raise ActiveRecord::Rollback if performed?
       end
     end
 
-    return if performed?
-
     render json: DeerjikistRepr.many(tag.reload.deerjikists)
   end
 
   def materials_by_name
     name = params[:name].to_s.strip
-    return render_bad_request('name は必須です．') if name.blank?
+    return head :bad_request if name.blank?
 
     tag = Tag.joins(:tag_name)
              .includes(:tag_name, :materials, tag_name: :wiki_page)
@@ -250,16 +247,17 @@ class TagsController < ApplicationController
 
     name = params[:name].to_s.strip
     category = params[:category].to_s.strip
-    return render_unprocessable_entity('名前は必須です．', field: :name) if name.blank?
+    return head :unprocessable_entity if name.blank? || category.blank?
-    return render_unprocessable_entity('カテゴリは必須です．', field: :category) if category.blank?
 
     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)
+      return render json: { error: 'システム・タグの名称は変更できません．' },
+                    status: :unprocessable_entity
     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 json: { error: 'ニコタグは変更できません．' },
+                    status: :unprocessable_entity
     end
 
     alias_names = params[:aliases].to_s.split.uniq
@@ -304,7 +302,8 @@ class TagsController < ApplicationController
     tag = Tag.find(params[:id])
 
     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 json: { error: 'ニコタグは変更できません．' },
+                    status: :unprocessable_entity
     end
 
     ApplicationRecord.transaction do
@@ -438,23 +437,4 @@ class TagsController < ApplicationController
   rescue
     nil
   end
-
-  def render_deerjikist_form_record_invalid deerjikist, index
-    fields = { }
-
-    deerjikist.errors.each do |error|
-      field =
-          case error.attribute
-          when :platform, :code
-            "deerjikists.#{ index }.#{ error.attribute }"
-          else
-            :deerjikists
-          end
-
-      fields[field] ||= []
-      fields[field] << error.full_message
-    end
-
-    render_validation_error fields:
-  end
 end

backend/app/controllers/theatre_comments_controller.rb

@@ -1,28 +1,21 @@
 class TheatreCommentsController < ApplicationController
   def index
-    limit = params[:limit].to_i
-    limit = 20 if limit <= 0
-
     no_gt = params[:no_gt].to_i
-    no_gt = 0 if no_gt < 0
+    no_gt = 0 if no_gt.negative?
 
     comments = TheatreComment
                .where(theatre_id: params[:theatre_id])
                .where('no > ?', no_gt)
                .order(no: :desc)
-               .limit(limit)
 
-    render json: comments.map {
+    render json: comments.as_json(include: { user: { only: [:id, :name] } })
-      _1.as_json(include: { user: { only: [:id, :name] } })
-          .merge(content: _1.discarded? ? nil : _1.content, deleted: _1.discarded?)
-    }
   end
 
   def create
     return head :unauthorized unless current_user
 
     content = params[:content]
-    return render_unprocessable_entity('本文は必須です．', field: :content) if content.blank?
+    return head :unprocessable_entity if content.blank?
 
     theatre = Theatre.find_by(id: params[:theatre_id])
     return head :not_found unless theatre
@@ -36,19 +29,4 @@ class TheatreCommentsController < ApplicationController
 
     render json: comment, status: :created
   end
-
-  def destroy
-    return head :unauthorized unless current_user
-
-    theatre_id = params[:theatre_id].to_i
-    no = params[:id].to_i
-
-    comment = TheatreComment.find_by(theatre_id:, no:)
-    return head :not_found unless comment
-    return head :forbidden unless comment.user == current_user
-
-    comment.discard!
-
-    head :no_content
-  end
 end

backend/app/controllers/theatre_programmes_controller.rb

@@ -1,22 +0,0 @@
-class TheatreProgrammesController < ApplicationController
-  def index
-    limit = params[:limit].to_i
-    limit = 100 if limit <= 0
-
-    position_gt = params[:position_gt].to_i
-    position_gt = 0 if position_gt < 0
-
-    programmes = TheatreProgramme
-                 .where(theatre_id: params[:theatre_id])
-                 .where('position > ?', position_gt)
-                 .includes(:post)
-                 .order(position: :desc).limit(100)
-                 .limit(limit)
-
-    render json: programmes.map { |programme|
-      programme.as_json.merge(post: { id: programme.post.id,
-                                      title: programme.post.title,
-                                      url: programme.post.url })
-    }
-  end
-end

backend/app/controllers/theatre_skip_events_controller.rb

@@ -1,22 +0,0 @@
-class TheatreSkipEventsController < ApplicationController
-  def index
-    limit = params[:limit].to_i
-    limit = 50 if limit <= 0
-
-    events =
-        TheatreSkipEvent
-        .where(theatre_id: params[:theatre_id])
-        .includes(:post, tags: :tag_name)
-        .order(created_at: :desc)
-        .limit(limit)
-
-    render json: events.map { |event|
-      { id: event.id,
-        theatre_id: event.theatre_id,
-        post: { id: event.post.id, title: event.post.title, url: event.post.url },
-        tags: event.tags.map { |tag| { id: tag.id, name: tag.name } },
-        programme_position: event.programme_position,
-        created_at: event.created_at }
-    }
-  end
-end

backend/app/controllers/theatres_controller.rb

@@ -31,7 +31,9 @@ class TheatresController < ApplicationController
       post_started_at = theatre.current_post_started_at
     end
 
-    render json: theatre_info_json(theatre, host_flg:, post_id:, post_started_at:)
+    render json: {
+        host_flg:, post_id:, post_started_at:,
+        watching_users: theatre.watching_users.as_json(only: [:id, :name]) }
   end
 
   def next_post
@@ -41,119 +43,12 @@ class TheatresController < ApplicationController
     return head :not_found unless theatre
     return head :forbidden if theatre.host_user != current_user
 
-    ApplicationRecord.transaction do
+    post = Post.where("url LIKE '%nicovideo.jp%'")
-      theatre.lock!
+           .or(Post.where("url LIKE '%youtube.com%'"))
-      TheatrePostAdvancer.call(theatre:)
+           .order('RAND()')
-    end
+           .first
+    theatre.update!(current_post: post, current_post_started_at: Time.current)
 
     head :no_content
   end
-
-  def skip_vote
-    return head :unauthorized unless current_user
-
-    theatre = Theatre.find_by(id: params[:id])
-    return head :not_found unless theatre
-    requested_post_id = params[:post_id].to_i
-    return head :unprocessable_entity if requested_post_id <= 0
-
-    skipped = false
-    conflicted = false
-
-    ApplicationRecord.transaction do
-      theatre.lock!
-      if theatre.current_post
-        TheatreWatchingUser.find_or_initialize_by(theatre:, user: current_user).tap {
-          _1.expires_at = 30.seconds.from_now
-        }.save!
-
-        if theatre.current_post_id != requested_post_id
-          conflicted = true
-          next
-        end
-
-        TheatreSkipVote.find_or_create_by!(theatre:, post_id: requested_post_id, user: current_user)
-
-        vote_status = skip_vote_status(theatre)
-        if vote_status[:votes_count] >= vote_status[:required_count]
-          TheatreSkipFinalizer.call(theatre:, user: current_user)
-          TheatrePostAdvancer.call(theatre:)
-          skipped = true
-        end
-      end
-    end
-
-    theatre.reload
-    return render json: theatre_info_json(theatre, skipped: false), status: :conflict if conflicted
-
-    render json: theatre_info_json(theatre, skipped:)
-  end
-
-  def unskip_vote
-    return head :unauthorized unless current_user
-
-    theatre = Theatre.find_by(id: params[:id])
-    return head :not_found unless theatre
-    requested_post_id = params[:post_id].to_i
-    return head :unprocessable_entity if requested_post_id <= 0
-
-    conflicted = false
-
-    theatre.with_lock do
-      if theatre.current_post
-        if theatre.current_post_id != requested_post_id
-          conflicted = true
-        else
-          TheatreSkipVote.where(theatre:, post_id: requested_post_id, user: current_user).delete_all
-        end
-      end
-    end
-
-    theatre.reload
-    return render json: theatre_info_json(theatre, skipped: false), status: :conflict if conflicted
-
-    render json: theatre_info_json(theatre, skipped: false)
-  end
-
-  def post_selection_weights
-    theatre = Theatre.find_by(id: params[:id])
-    return head :not_found unless theatre
-
-    render json: TheatrePostSelector.new(theatre:).weight_json
-  end
-
-  private
-
-  def theatre_info_json(theatre, host_flg: nil, post_id: nil, post_started_at: nil, skipped: nil)
-    host_flg = theatre.host_user_id == current_user&.id if host_flg.nil?
-    post_id = theatre.current_post_id if post_id.nil?
-    post_started_at = theatre.current_post_started_at if post_started_at.nil?
-
-    json = { host_flg:,
-             post_id:,
-             post_started_at:,
-             post_elapsed_ms: post_started_at ? ((Time.current - post_started_at) * 1000).floor : nil,
-             watching_users: theatre.watching_users.as_json(only: [:id, :name]),
-             skip_vote: skip_vote_status(theatre) }
-    json[:skipped] = skipped unless skipped.nil?
-    json
-  end
-
-  def skip_vote_status(theatre)
-    watching_user_ids = theatre.watching_users.ids
-    watching_users_count = watching_user_ids.size
-    required_count = (watching_users_count / 2) + 1
-    post = theatre.current_post
-    votes =
-        if post
-          TheatreSkipVote.where(theatre:, post:, user_id: watching_user_ids)
-        else
-          TheatreSkipVote.none
-        end
-
-    { votes_count: post ? votes.count : 0,
-      required_count:,
-      watching_users_count:,
-      voted: post && current_user ? votes.exists?(user_id: current_user.id) : false }
-  end
 end

backend/app/controllers/users_controller.rb

@@ -42,12 +42,12 @@ class UsersController < ApplicationController
     return head :unauthorized if user&.id != params[:id].to_i
 
     name = params[:name]
-    return render_unprocessable_entity('名前は必須です．', field: :name) if name.blank?
+    return head :bad_request if name.blank?
 
     if user.update(name:)
       render json: user.slice(:id, :name, :inheritance_code, :role), status: :ok
     else
-      render_validation_error user
+      render json: user.errors, status: :unprocessable_entity
     end
   end
 

backend/app/controllers/wiki_pages_controller.rb

@@ -46,7 +46,7 @@ class WikiPagesController < ApplicationController
 
   def diff
     id = params[:id]
-    return render_bad_request('id は必須です．') if id.blank?
+    return head :bad_request if id.blank?
 
     from = params[:from].presence
     to = params[:to].presence
@@ -56,7 +56,7 @@ class WikiPagesController < ApplicationController
     from_rev = from && page.wiki_revisions.find(from)
     to_rev = to ? page.wiki_revisions.find(to) : page.current_revision
     if ((from_rev && !(from_rev.content?)) || !(to_rev&.content?))
-      return render_unprocessable_entity('差分を表示できない版です．')
+      return head :unprocessable_entity
     end
 
     diffs = Diff::LCS.sdiff(from_rev&.body&.lines || [], to_rev.body.lines)
@@ -89,8 +89,7 @@ class WikiPagesController < ApplicationController
     body = params[:body].to_s
     message = params[:message].presence
 
-    return render_unprocessable_entity('タイトルは必須です．', field: :title) if title.blank?
+    return head :unprocessable_entity if title.blank? || body.blank?
-    return render_unprocessable_entity('本文は必須です．', field: :body) if body.blank?
 
     tag_name = TagName.find_undiscard_or_create_by!(name: title)
 
@@ -102,10 +101,8 @@ class WikiPagesController < ApplicationController
             message:)
 
     render json: WikiPageRepr.base(page), status: :created
-  rescue ActiveRecord::RecordInvalid => e
+  rescue ActiveRecord::RecordInvalid, ActiveRecord::RecordNotUnique
-    render_validation_error e.record
+    head :unprocessable_entity
-  rescue ActiveRecord::RecordNotUnique
-    render_record_not_unique
   end
 
   def update
@@ -115,8 +112,7 @@ class WikiPagesController < ApplicationController
     title = params[:title]&.strip
     body = params[:body].to_s
 
-    return render_unprocessable_entity('タイトルは必須です．', field: :title) if title.blank?
+    return head :unprocessable_entity if title.blank? || body.blank?
-    return render_unprocessable_entity('本文は必須です．', field: :body) if body.blank?
 
     page = WikiPage.find(params[:id])
     base_revision_id = params[:base_revision_id].presence

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_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 if new_record?
-
-    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

@@ -1,25 +0,0 @@
-class GekanatorQuestionSuggestion < ApplicationRecord
-  MAX_QUESTIONS_PER_GAME = 3
-  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] }
-  validate :question_suggestion_limit_per_game, on: :create
-
-  private
-
-  def question_suggestion_limit_per_game
-    return if gekanator_game_id.blank?
-
-    count = GekanatorQuestionSuggestion.where(gekanator_game_id:).count
-    if count >= MAX_QUESTIONS_PER_GAME
-      errors.add(:base, '質問追加数を超えてゐます．')
-    end
-  end
-end

backend/app/models/post.rb

@@ -11,17 +11,6 @@ class Post < ApplicationRecord
   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',
@@ -67,7 +56,38 @@ class Post < ApplicationRecord
     super(options).merge(thumbnail: nil)
   end
 
-  def snapshot_tag_names = tags.joins(:tag_name).order('tag_names.name').pluck('tag_names.name')
+  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) }-#{ 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
+
+    if h.positive?
+      '%d:%02d:%02d' % [h, min, s]
+    else
+      '%d:%02d' % [min, s]
+    end
+  end
 
   def snapshot_parent_post_ids = parents.order(:id).pluck(:id)
 
@@ -105,7 +125,7 @@ class Post < ApplicationRecord
     return if !(f) || !(b)
 
     if f >= b
-      errors.add :original_created_at, 'オリジナルの作成日時の順番がをかしぃです．'
+      errors.add :original_created_before, 'オリジナルの作成日時の順番がをかしぃです．'
     end
   end
 

backend/app/models/post_tag.rb

@@ -10,6 +10,12 @@ 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

@@ -0,0 +1,20 @@
+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, presence: true,
+                     numericality: { only_integer: true, greater_than: :begin_ms }
+end

backend/app/models/tag.rb

@@ -81,7 +81,7 @@ class Tag < ApplicationRecord
 
   def material_id = materials.first&.id
 
-  def has_deerjikists = deerjikists.loaded? ? deerjikists.any? : deerjikists.exists?
+  def has_deerjikists = deerjikists.present?
 
   def self.tagme = find_or_create_by_tag_name!('タグ希望', category: :meta)
   def self.bot = find_or_create_by_tag_name!('bot操作', category: :meta)
@@ -92,22 +92,50 @@ class Tag < ApplicationRecord
 
   def self.normalise_tags! tag_names, with_tagme: true,
                                       with_no_deerjikist: true,
-                                      deny_nico: true
+                                      deny_nico: true,
+                                      with_sections: false
     if deny_nico && tag_names.any? { |n| n.downcase.start_with?('nico:') }
       raise NicoTagNormalisationError
     end
 
+    sections = { }
     tags = tag_names.map do |name|
       pf, cat = CATEGORY_PREFIXES.find { |p, _| name.downcase.start_with?(p) } || ['', nil]
-      name = TagName.canonicalise(name.sub(/\A#{ pf }/i, '')).first
+
+      name = name.sub(/\A#{ pf }/i, '')
+
+      sections_by_tag = []
+      while n = name.sub!(/^(\S*?)\[([0-9:.]*?)-([0-9:.]*?)\](\S*?)$/, '\1\4 \2 \3')
+        name, *section_raw = n.split
+
+        begin_ms, end_ms = section_raw.map { time_to_ms(_1) }
+        next if begin_ms == end_ms
+
+        begin_ms, end_ms = end_ms, begin_ms if begin_ms > end_ms
+
+        sections_by_tag << [begin_ms, end_ms]
+      end
+
+      name = TagName.canonicalise(name).first
+
       find_or_create_by_tag_name!(name, category: (cat || :general)).tap do |tag|
         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)
       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)
+    tags.uniq!(&:id)
+
+    if with_sections
+      { tags:, sections: }
+    else
+      tags
+    end
   end
 
   def self.expand_parent_tags tags
@@ -228,4 +256,23 @@ 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
+    parts = str.split(':')
+
+    s_part = parts.pop
+    s, ms = s_part.split('.')
+
+    total_s = s.to_i
+
+    if parts.length >= 1
+      total_s += parts.pop.to_i * 60
+    end
+
+    if parts.length >= 1
+      total_s += parts.pop.to_i * 3_600
+    end
+
+    total_s * 1_000 + ms.to_s.ljust(3, '0')[0, 3].to_i
+  end
 end

backend/app/models/theatre.rb

@@ -7,10 +7,6 @@ class Theatre < ApplicationRecord
            class_name: 'TheatreWatchingUser', inverse_of: :theatre
   has_many :watching_users, through: :active_theatre_watching_users, source: :user
 
-  has_many :programmes, class_name: 'TheatreProgramme'
-  has_many :skip_votes, class_name: 'TheatreSkipVote', dependent: :delete_all
-  has_many :skip_events, class_name: 'TheatreSkipEvent', dependent: :delete_all
-
   belongs_to :host_user, class_name: 'User', optional: true
   belongs_to :current_post, class_name: 'Post', optional: true
   belongs_to :created_by_user, class_name: 'User'

backend/app/models/theatre_programme.rb

@@ -1,6 +0,0 @@
-class TheatreProgramme < ApplicationRecord
-  self.primary_key = :theatre_id, :position
-
-  belongs_to :theatre
-  belongs_to :post
-end

backend/app/models/theatre_skip_event.rb

@@ -1,10 +0,0 @@
-class TheatreSkipEvent < ApplicationRecord
-  belongs_to :theatre
-  belongs_to :post
-  belongs_to :skipped_by_user, class_name: 'User'
-
-  has_many :voters, class_name: 'TheatreSkipEventVoter', dependent: :delete_all
-  has_many :event_tags, class_name: 'TheatreSkipEventTag', dependent: :delete_all
-  has_many :users, through: :voters
-  has_many :tags, through: :event_tags
-end

backend/app/models/theatre_skip_event_tag.rb

@@ -1,6 +0,0 @@
-class TheatreSkipEventTag < ApplicationRecord
-  self.primary_key = :theatre_skip_event_id, :tag_id
-
-  belongs_to :theatre_skip_event
-  belongs_to :tag
-end

backend/app/models/theatre_skip_event_voter.rb

@@ -1,6 +0,0 @@
-class TheatreSkipEventVoter < ApplicationRecord
-  self.primary_key = :theatre_skip_event_id, :user_id
-
-  belongs_to :theatre_skip_event
-  belongs_to :user
-end

backend/app/models/theatre_skip_vote.rb

@@ -1,7 +0,0 @@
-class TheatreSkipVote < ApplicationRecord
-  self.primary_key = :theatre_id, :post_id, :user_id
-
-  belongs_to :theatre
-  belongs_to :post
-  belongs_to :user
-end

backend/app/representations/post_repr.rb

@@ -2,65 +2,20 @@
 
 
 module PostRepr
-  BASE_FIELDS = [
+  BASE = { include: { tags: TagRepr::BASE, uploaded_user: UserRepr::BASE },
-      :id,
+           methods: [:parent_posts, :child_posts, :sibling_posts] }.freeze
-      :version_no,
-      :url,
-      :title,
-      :thumbnail_base,
-      :original_created_from,
-      :original_created_before,
-      :created_at,
-      :updated_at
-  ].freeze
 
   module_function
 
   def base post, current_user = nil
-    json = common(post)
+    json = post.as_json(BASE)
-    json['tags'] = tag_json(post.tags)
+    return json.merge(viewed: false) unless current_user
-    json['uploaded_user'] = post.uploaded_user && UserRepr.base(post.uploaded_user)
-    json['viewed'] = current_user ? current_user.viewed?(post) : false
-    json
-  end
 
-  def detail post, current_user = nil, parent_posts: [], child_posts: [],
+    viewed = current_user.viewed?(post)
-             sibling_posts: { }, related: []
+    json.merge(viewed:)
-    base(post, current_user).merge(
-        'parent_posts' => cards(parent_posts),
-        'child_posts' => cards(child_posts),
-        'sibling_posts' => sibling_posts.transform_keys(&:to_s).transform_values { |posts|
-          cards(posts)
-        },
-        'related' => cards(related))
-  end
-
-  def card post
-    common(post).merge('parent_posts' => [], 'child_posts' => [])
-  end
-
-  def cards posts
-    posts.map { |post| card(post) }
   end
 
   def many posts, current_user = nil
     posts.map { |p| base(p, current_user) }
   end
-
-  def common post
-    BASE_FIELDS.to_h { |field| [field.to_s, post.public_send(field)] }
-               .merge('thumbnail' => thumbnail_url(post))
-  end
-
-  def tag_json tags
-    tags.map { |tag| TagRepr.inline(tag) }
-  end
-
-  def thumbnail_url post
-    return nil unless post.thumbnail.attached?
-
-    Rails.application.routes.url_helpers.rails_blob_url(post.thumbnail, only_path: false)
-  rescue
-    nil
-  end
 end

backend/app/representations/tag_repr.rb

@@ -12,9 +12,5 @@ module TagRepr
                             parents: tag.parents.map { _1.as_json(BASE) })
   end
 
-  def inline tag
-    tag.as_json(BASE).merge(aliases: [], parents: [])
-  end
-
   def many(tags) = tags.map { |t| base(t) }
 end

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/theatre_post_advancer.rb

@@ -1,29 +0,0 @@
-class TheatrePostAdvancer
-  def self.call(theatre:)
-    new(theatre:).call
-  end
-
-  def initialize(theatre:)
-    @theatre = theatre
-  end
-
-  def call
-    previous_post = theatre.current_post
-    post = TheatrePostSelector.new(theatre:).select
-
-    TheatreSkipVote.where(theatre:, post: previous_post).delete_all if previous_post
-
-    theatre.update!(current_post: post, current_post_started_at: post ? Time.current : nil)
-
-    if post
-      position = (theatre.programmes.maximum(:position) || 0) + 1
-      theatre.programmes.create!(position:, post:)
-    end
-
-    post
-  end
-
-  private
-
-  attr_reader :theatre
-end

backend/app/services/theatre_post_selector.rb

@@ -1,119 +0,0 @@
-class TheatrePostSelector
-  Candidate = Struct.new(:post, :weight, :penalty, :tags, keyword_init: true)
-  ELIGIBLE_POST_URL_CONDITION =
-      ["url LIKE '%nicovideo.jp%'",
-       "url LIKE '%youtube.com/watch%'",
-       "url LIKE '%youtu.be/%'"]
-      .join(' OR ')
-
-  def initialize theatre:
-    @theatre = theatre
-  end
-
-  def select
-    candidates = weighted_candidates
-    return nil if candidates.empty?
-
-    total = candidates.sum(&:weight)
-    target = rand * total
-
-    candidates.each do |candidate|
-      target -= candidate.weight
-      return candidate.post if target <= 0
-    end
-
-    candidates.last.post
-  end
-
-  def weight_json limit: 20
-    candidates = weighted_candidates
-    sorted = candidates.sort_by { |candidate| [candidate.weight, candidate.post.id] }
-
-    { tag_penalties: tag_penalty_json,
-      lightest_posts: post_weight_json(sorted.first(limit)),
-      heaviest_posts: post_weight_json(sorted.reverse.first(limit)) }
-  end
-
-  private
-
-  attr_reader :theatre
-
-  def weighted_candidates
-    @weighted_candidates ||= begin
-      penalties = tag_penalties
-      posts = eligible_posts.includes(tags: :tag_name).to_a
-
-      posts.map do |post|
-        post_tags = post.tags.to_a
-        penalty = post_tags.sum { |tag| penalties[tag.id].to_i }
-
-        Candidate.new(
-            post:,
-            penalty:,
-            tags: post_tags,
-            weight: 1.0 / (1.0 + penalty))
-      end
-    end
-  end
-
-  def eligible_posts
-    posts = Post.where(ELIGIBLE_POST_URL_CONDITION)
-    posts = posts.where.not(id: theatre.current_post_id) if theatre.current_post_id
-    posts
-  end
-
-  def active_user_ids
-    @active_user_ids ||= theatre.watching_users.ids
-  end
-
-  def tag_penalties
-    @tag_penalties ||=
-      if active_user_ids.empty?
-        {}
-      else
-        TheatreSkipEventVoter
-          .joins(theatre_skip_event: :event_tags)
-          .where(user_id: active_user_ids)
-          .group('theatre_skip_event_tags.tag_id')
-          .count
-      end
-  end
-
-  def tag_penalty_json
-    return [] if tag_penalties.empty?
-
-    tags = Tag.where(id: tag_penalties.keys).includes(:tag_name).index_by(&:id)
-
-    tag_penalties
-      .map { |tag_id, penalty|
-        tag = tags[tag_id]
-        next unless tag
-
-        { tag: light_tag_json(tag),
-          penalty: }
-      }
-      .compact
-      .sort_by { |row| [-row[:penalty], row[:tag][:name].to_s] }
-  end
-
-  def post_weight_json candidates
-    candidates.map { |candidate|
-      { post: light_post_json(candidate.post),
-        weight: candidate.weight,
-        penalty: candidate.penalty,
-        tags: candidate.tags.map { |tag| light_tag_json(tag) } }
-    }
-  end
-
-  def light_post_json post
-    { id: post.id,
-      title: post.title,
-      url: post.url }
-  end
-
-  def light_tag_json tag
-    { id: tag.id,
-      name: tag.name,
-      category: tag.category }
-  end
-end

backend/app/services/theatre_skip_finalizer.rb

@@ -1,40 +0,0 @@
-class TheatreSkipFinalizer
-  def self.call(theatre:, user:)
-    new(theatre:, user:).call
-  end
-
-  def initialize(theatre:, user:)
-    @theatre = theatre
-    @user = user
-  end
-
-  def call
-    return unless theatre.current_post
-
-    post = theatre.current_post
-    voters = TheatreSkipVote.where(theatre:, post:).includes(:user).map(&:user)
-    return if voters.empty?
-
-    event = TheatreSkipEvent.create!(
-        theatre:,
-        post:,
-        skipped_by_user: user,
-        programme_position: theatre.programmes.maximum(:position))
-
-    voters.uniq(&:id).each do |voter|
-      TheatreSkipEventVoter.create!(theatre_skip_event: event, user: voter)
-    end
-
-    post.tags.find_each do |tag|
-      TheatreSkipEventTag.create!(theatre_skip_event: event, tag:)
-    end
-
-    TheatreSkipVote.where(theatre:, post:).delete_all
-
-    event
-  end
-
-  private
-
-  attr_reader :theatre, :user
-end

backend/config/routes.rb

@@ -63,24 +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
-
   resources :users, only: [:create, :update] do
     collection do
       post :verify
@@ -103,14 +85,9 @@ Rails.application.routes.draw do
     member do
       put :watching
       patch :next_post
-      put :skip_vote
-      delete :skip_vote, action: :unskip_vote
-      get :post_selection_weights
     end
 
-    resources :comments, controller: :theatre_comments, only: [:index, :create, :destroy]
+    resources :comments, controller: :theatre_comments, only: [:index, :create]
-    resources :programmes, controller: :theatre_programmes, only: [:index]
-    resources :skip_events, controller: :theatre_skip_events, only: [:index]
   end
 
   resources :materials, only: [:index, :show, :create, :update, :destroy]

backend/db/migrate/20260514221900_create_theatre_programmes.rb

@@ -1,10 +0,0 @@
-class CreateTheatreProgrammes < ActiveRecord::Migration[8.0]
-  def change
-    create_table :theatre_programmes, primary_key: [:theatre_id, :position] do |t|
-      t.references :theatre, null: false, foreign_key: true
-      t.integer :position, null: false
-      t.references :post, null: false, foreign_key: true
-      t.datetime :created_at, null: false
-    end
-  end
-end

backend/db/migrate/20260518235300_create_post_tag_sections.rb

@@ -0,0 +1,19 @@
+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: false
+      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 'begin_ms < end_ms',
+                         name: 'chk_post_tag_sections_end_ms_after_begin_ms'
+    end
+  end
+end

backend/db/migrate/20260519013100_add_video_ms_to_posts.rb

@@ -0,0 +1,9 @@
+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/20260606000000_create_theatre_skip_votes_and_events.rb

@@ -1,36 +0,0 @@
-class CreateTheatreSkipVotesAndEvents < ActiveRecord::Migration[8.0]
-  def change
-    create_table :theatre_skip_votes, primary_key: [:theatre_id, :post_id, :user_id] do |t|
-      t.references :theatre, null: false, foreign_key: true
-      t.references :post, null: false, foreign_key: true
-      t.references :user, null: false, foreign_key: true
-      t.timestamps
-    end
-
-    create_table :theatre_skip_events do |t|
-      t.references :theatre, null: false, foreign_key: true
-      t.references :post, null: false, foreign_key: true
-      t.references :skipped_by_user, null: false, foreign_key: { to_table: :users }
-      t.integer :programme_position
-      t.datetime :created_at, null: false
-    end
-
-    create_table :theatre_skip_event_voters, primary_key: [:theatre_skip_event_id, :user_id] do |t|
-      t.references :theatre_skip_event, null: false, foreign_key: true
-      t.references :user, null: false, foreign_key: true
-    end
-
-    create_table :theatre_skip_event_tags, primary_key: [:theatre_skip_event_id, :tag_id] do |t|
-      t.references :theatre_skip_event, null: false, foreign_key: true
-      t.references :tag, null: false, foreign_key: true
-    end
-
-    add_index :theatre_skip_events, [:theatre_id, :created_at]
-    add_index :theatre_skip_votes, [:theatre_id, :post_id, :created_at],
-              name: 'idx_theatre_skip_votes_theatre_post_created'
-    add_index :theatre_skip_event_voters, [:user_id, :theatre_skip_event_id],
-              name: 'idx_theatre_skip_event_voters_user_event'
-    add_index :theatre_skip_event_tags, [:tag_id, :theatre_skip_event_id],
-              name: 'idx_theatre_skip_event_tags_tag_event'
-  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/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_06_12_000000) do
+ActiveRecord::Schema[8.0].define(version: 2026_05_19_013100) 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_06_12_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"
@@ -210,6 +137,19 @@ ActiveRecord::Schema[8.0].define(version: 2026_06_12_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", null: false
+    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 "`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
@@ -260,8 +200,11 @@ ActiveRecord::Schema[8.0].define(version: 2026_06_12_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
 
@@ -356,55 +299,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_06_12_000000) do
     t.index ["user_id"], name: "index_theatre_comments_on_user_id"
   end
 
-  create_table "theatre_programmes", primary_key: ["theatre_id", "position"], charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.bigint "theatre_id", null: false
-    t.integer "position", null: false
-    t.bigint "post_id", null: false
-    t.datetime "created_at", null: false
-    t.index ["post_id"], name: "index_theatre_programmes_on_post_id"
-    t.index ["theatre_id"], name: "index_theatre_programmes_on_theatre_id"
-  end
-
-  create_table "theatre_skip_event_tags", primary_key: ["theatre_skip_event_id", "tag_id"], charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.bigint "theatre_skip_event_id", null: false
-    t.bigint "tag_id", null: false
-    t.index ["tag_id", "theatre_skip_event_id"], name: "idx_theatre_skip_event_tags_tag_event"
-    t.index ["tag_id"], name: "index_theatre_skip_event_tags_on_tag_id"
-    t.index ["theatre_skip_event_id"], name: "index_theatre_skip_event_tags_on_theatre_skip_event_id"
-  end
-
-  create_table "theatre_skip_event_voters", primary_key: ["theatre_skip_event_id", "user_id"], charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.bigint "theatre_skip_event_id", null: false
-    t.bigint "user_id", null: false
-    t.index ["theatre_skip_event_id"], name: "index_theatre_skip_event_voters_on_theatre_skip_event_id"
-    t.index ["user_id", "theatre_skip_event_id"], name: "idx_theatre_skip_event_voters_user_event"
-    t.index ["user_id"], name: "index_theatre_skip_event_voters_on_user_id"
-  end
-
-  create_table "theatre_skip_events", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.bigint "theatre_id", null: false
-    t.bigint "post_id", null: false
-    t.bigint "skipped_by_user_id", null: false
-    t.integer "programme_position"
-    t.datetime "created_at", null: false
-    t.index ["post_id"], name: "index_theatre_skip_events_on_post_id"
-    t.index ["skipped_by_user_id"], name: "index_theatre_skip_events_on_skipped_by_user_id"
-    t.index ["theatre_id", "created_at"], name: "index_theatre_skip_events_on_theatre_id_and_created_at"
-    t.index ["theatre_id"], name: "index_theatre_skip_events_on_theatre_id"
-  end
-
-  create_table "theatre_skip_votes", primary_key: ["theatre_id", "post_id", "user_id"], charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.bigint "theatre_id", null: false
-    t.bigint "post_id", null: false
-    t.bigint "user_id", null: false
-    t.datetime "created_at", null: false
-    t.datetime "updated_at", null: false
-    t.index ["post_id"], name: "index_theatre_skip_votes_on_post_id"
-    t.index ["theatre_id", "post_id", "created_at"], name: "idx_theatre_skip_votes_theatre_post_created"
-    t.index ["theatre_id"], name: "index_theatre_skip_votes_on_theatre_id"
-    t.index ["user_id"], name: "index_theatre_skip_votes_on_user_id"
-  end
-
   create_table "theatre_watching_users", primary_key: ["theatre_id", "user_id"], charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.bigint "theatre_id", null: false
     t.bigint "user_id", null: false
@@ -412,6 +306,7 @@ ActiveRecord::Schema[8.0].define(version: 2026_06_12_000000) do
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
     t.index ["expires_at"], name: "index_theatre_watching_users_on_expires_at"
+    t.index ["theatre_id", "expires_at"], name: "idx_on_theatre_id_skip_expires_at_4c8de1dd42"
     t.index ["theatre_id", "expires_at"], name: "index_theatre_watching_users_on_theatre_id_and_expires_at"
     t.index ["theatre_id"], name: "index_theatre_watching_users_on_theatre_id"
     t.index ["user_id"], name: "index_theatre_watching_users_on_user_id"
@@ -551,18 +446,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_06_12_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_versions", "materials"
   add_foreign_key "material_versions", "materials", column: "parent_id"
   add_foreign_key "material_versions", "tags"
@@ -580,6 +463,8 @@ ActiveRecord::Schema[8.0].define(version: 2026_06_12_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"
@@ -598,18 +483,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_06_12_000000) do
   add_foreign_key "tags", "tag_names"
   add_foreign_key "theatre_comments", "theatres"
   add_foreign_key "theatre_comments", "users"
-  add_foreign_key "theatre_programmes", "posts"
-  add_foreign_key "theatre_programmes", "theatres"
-  add_foreign_key "theatre_skip_event_tags", "tags"
-  add_foreign_key "theatre_skip_event_tags", "theatre_skip_events"
-  add_foreign_key "theatre_skip_event_voters", "theatre_skip_events"
-  add_foreign_key "theatre_skip_event_voters", "users"
-  add_foreign_key "theatre_skip_events", "posts"
-  add_foreign_key "theatre_skip_events", "theatres"
-  add_foreign_key "theatre_skip_events", "users", column: "skipped_by_user_id"
-  add_foreign_key "theatre_skip_votes", "posts"
-  add_foreign_key "theatre_skip_votes", "theatres"
-  add_foreign_key "theatre_skip_votes", "users"
   add_foreign_key "theatre_watching_users", "theatres"
   add_foreign_key "theatre_watching_users", "users"
   add_foreign_key "theatres", "posts", column: "current_post_id"

backend/spec/factories/post_tag_sections.rb

@@ -0,0 +1,8 @@
+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

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

backend/spec/factories/posts.rb

@@ -0,0 +1,8 @@
+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/post_tag_spec.rb

@@ -0,0 +1,29 @@
+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
+  end
+end

backend/spec/requests/error_responses_spec.rb

@@ -1,47 +0,0 @@
-require 'rails_helper'
-
-RSpec.describe 'error responses', type: :request do
-  describe 'manual input errors' do
-    it 'returns a stable payload for bad requests' do
-      get '/tags/name/%20/deerjikists'
-
-      expect(response).to have_http_status(:bad_request)
-      expect(json).to include(
-          'type' => 'bad_request',
-          'message' => be_present,
-          'errors' => {},
-          'base_errors' => [be_present])
-    end
-
-    it 'returns a stable field-error payload for unprocessable requests' do
-      member = create(:user, :member)
-      tag = create(:tag, :general, name: 'error_response_tag')
-      sign_in_as(member)
-
-      patch "/tags/#{ tag.id }", params: { category: 'nico' }
-
-      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．',
-          'base_errors' => [])
-      expect(json.fetch('errors')).to include(
-          'category' => ['ニコタグは変更できません．'])
-    end
-  end
-
-  describe 'model validation errors' do
-    it 'returns field messages for model errors' do
-      user = create(:user)
-      sign_in_as(user)
-
-      put "/users/#{ user.id }", params: { name: 'a' * 256 }
-
-      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').fetch('name')).to include(be_present)
-    end
-  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_learning_spec.rb

@@ -1,786 +0,0 @@
-require 'rails_helper'
-
-RSpec.describe 'Gekanator learning API', type: :request do
-  let(:admin) { create(:user, :admin) }
-  let(:member) { create(:user, :member) }
-  let(:other_user) { create(:user, :member) }
-
-  let!(:guessed_post) do
-    Post.create!(
-      title: 'guessed',
-      url: 'https://example.com/guessed'
-    )
-  end
-
-  let!(:correct_post) do
-    Post.create!(
-      title: 'correct',
-      url: 'https://example.com/correct'
-    )
-  end
-
-  let!(:other_post) do
-    Post.create!(
-      title: 'other',
-      url: 'https://example.com/other'
-    )
-  end
-
-  let!(:game) do
-    GekanatorGame.create!(
-      user: admin,
-      guessed_post: guessed_post,
-      correct_post: correct_post,
-      won: false,
-      question_count: 1,
-      answers: [
-        {
-          'question_id' => 'tag:character:喜多郁代',
-          'question_text' => '喜多ちゃんが関係してる?',
-          'answer' => 'yes',
-          'original_answer' => 'yes'
-        }
-      ]
-    )
-  end
-
-  def create_post_similarity_question!(
-    text: '喜多ちゃんが泣いてる?',
-    post: correct_post,
-    answer: 'yes',
-    status: 'accepted',
-    source: 'user_suggested',
-    priority_weight: 1.2
-  )
-    GekanatorQuestion.create!(
-      text: text,
-      kind: 'post_similarity',
-      source: source,
-      status: status,
-      priority_weight: priority_weight,
-      condition: {
-        type: 'post-similarity',
-        postId: post.id,
-        answer: answer,
-        threshold: 0.65
-      },
-      created_by: admin
-    )
-  end
-
-  describe 'POST /gekanator/games' do
-    it 'stores a game result for an admin user' do
-      sign_in_as admin
-
-      post '/gekanator/games', params: {
-        guessed_post_id: guessed_post.id,
-        correct_post_id: correct_post.id,
-        answers: [
-          {
-            question_id: 'tag:character:喜多郁代',
-            question_text: '喜多ちゃんが関係してる?',
-            answer: 'yes',
-            original_answer: 'yes'
-          }
-        ]
-      }
-
-      expect(response).to have_http_status(:created)
-
-      created = GekanatorGame.find(json['id'])
-      expect(created.user).to eq(admin)
-      expect(created.guessed_post).to eq(guessed_post)
-      expect(created.correct_post).to eq(correct_post)
-      expect(created.won).to eq(false)
-      expect(created.question_count).to eq(1)
-      expect(created.answers).to eq([
-        {
-          'question_id' => 'tag:character:喜多郁代',
-          'question_text' => '喜多ちゃんが関係してる?',
-          'answer' => 'yes',
-          'original_answer' => 'yes'
-        }
-      ])
-    end
-
-    it 'stores a won game when guessed_post_id equals correct_post_id' do
-      sign_in_as admin
-
-      post '/gekanator/games', params: {
-        guessed_post_id: correct_post.id,
-        correct_post_id: correct_post.id,
-        answers: []
-      }
-
-      expect(response).to have_http_status(:created)
-      expect(GekanatorGame.find(json['id']).won).to eq(true)
-    end
-
-    it 'rejects a game without correct_post_id' do
-      sign_in_as admin
-
-      expect {
-        post '/gekanator/games', params: {
-          guessed_post_id: guessed_post.id,
-          answers: []
-        }
-      }.not_to change { GekanatorGame.count }
-
-      expect(response).to have_http_status(:unprocessable_entity)
-    end
-
-    it 'stores a game result for a non-admin user' do
-      sign_in_as member
-
-      post '/gekanator/games', params: {
-        guessed_post_id: guessed_post.id,
-        correct_post_id: correct_post.id,
-        answers: []
-      }
-
-      expect(response).to have_http_status(:created)
-      expect(GekanatorGame.find(json['id']).user).to eq(member)
-    end
-
-    it 'returns unauthorized without a user' do
-      post '/gekanator/games', params: {
-        guessed_post_id: guessed_post.id,
-        correct_post_id: correct_post.id,
-        answers: []
-      }
-
-      expect(response).to have_http_status(:unauthorized)
-    end
-  end
-
-  describe 'POST /gekanator/question_suggestions' do
-    it 'creates a suggestion and promotes yes answer to an accepted post_similarity question' do
-      sign_in_as admin
-
-      expect {
-        post '/gekanator/question_suggestions', params: {
-          gekanator_game_id: game.id,
-          question_text: '喜多ちゃんが泣いてる?',
-          answer: 'yes'
-        }
-      }.to change { GekanatorQuestionSuggestion.count }.by(1)
-        .and change { GekanatorQuestion.count }.by(1)
-        .and change { GekanatorQuestionExample.count }.by(1)
-
-      expect(response).to have_http_status(:created)
-
-      suggestion = GekanatorQuestionSuggestion.last
-      question = GekanatorQuestion.last
-      example = GekanatorQuestionExample.last
-
-      expect(json).to include(
-        'id' => suggestion.id,
-        'count' => 1
-      )
-
-      expect(suggestion).to have_attributes(
-        gekanator_game_id: game.id,
-        user_id: admin.id,
-        question_text: '喜多ちゃんが泣いてる?',
-        answer: 'yes',
-        processed: true
-      )
-
-      expect(question).to have_attributes(
-        text: '喜多ちゃんが泣いてる?',
-        kind: 'post_similarity',
-        source: 'user_suggested',
-        status: 'accepted',
-        priority_weight: 1.2,
-        gekanator_question_suggestion_id: suggestion.id,
-        created_by_id: admin.id
-      )
-      expect(question.condition).to include(
-        'type' => 'post-similarity',
-        'postId' => correct_post.id,
-        'answer' => 'yes',
-        'threshold' => 0.65
-      )
-
-      expect(example).to have_attributes(
-        gekanator_question_id: question.id,
-        post_id: correct_post.id,
-        user_id: admin.id,
-        gekanator_game_id: game.id,
-        answer: 'yes',
-        source: 'initial_suggestion',
-        weight: 1.0
-      )
-    end
-
-    it 'promotes no, partial, and probably_no answers' do
-      sign_in_as admin
-
-      ['no', 'partial', 'probably_no'].each do |answer|
-        expect {
-          post '/gekanator/question_suggestions', params: {
-            gekanator_game_id: game.id,
-            question_text: "answer #{answer} question?",
-            answer: answer
-          }
-        }.to change { GekanatorQuestion.count }.by(1)
-          .and change { GekanatorQuestionExample.count }.by(1)
-
-        expect(response).to have_http_status(:created)
-        expect(GekanatorQuestion.last.condition['answer']).to eq(answer)
-        expect(GekanatorQuestionExample.last.answer).to eq(answer)
-      end
-    end
-
-    it 'does not promote unknown answers' do
-      sign_in_as admin
-
-      expect {
-        post '/gekanator/question_suggestions', params: {
-          gekanator_game_id: game.id,
-          question_text: 'よく分からない質問?',
-          answer: 'unknown'
-        }
-      }.to change { GekanatorQuestionSuggestion.count }.by(1)
-        .and change { GekanatorQuestion.count }.by(0)
-        .and change { GekanatorQuestionExample.count }.by(0)
-
-      expect(response).to have_http_status(:created)
-      expect(GekanatorQuestionSuggestion.last.processed).to eq(false)
-    end
-
-    it 'limits suggestions to three per game' do
-      sign_in_as admin
-
-      3.times do |i|
-        GekanatorQuestionSuggestion.create!(
-          gekanator_game: game,
-          user: admin,
-          question_text: "existing question #{i}",
-          answer: 'unknown'
-        )
-      end
-
-      expect {
-        post '/gekanator/question_suggestions', params: {
-          gekanator_game_id: game.id,
-          question_text: 'fourth question?',
-          answer: 'yes'
-        }
-      }.not_to change { GekanatorQuestionSuggestion.count }
-
-      expect(response).to have_http_status(:unprocessable_entity)
-    end
-
-    it 'allows a non-admin user to suggest a question for their own game' do
-      member_game = GekanatorGame.create!(
-        user: member,
-        guessed_post: guessed_post,
-        correct_post: correct_post,
-        won: false,
-        question_count: 1,
-        answers: [{ 'question_id' => 'tag:1', 'answer' => 'yes' }]
-      )
-      sign_in_as member
-
-      expect {
-        post '/gekanator/question_suggestions', params: {
-          gekanator_game_id: member_game.id,
-          question_text: 'member question?',
-          answer: 'yes'
-        }
-      }.to change { GekanatorQuestionSuggestion.count }.by(1)
-
-      expect(response).to have_http_status(:created)
-      expect(GekanatorQuestionSuggestion.last).to have_attributes(
-        gekanator_game_id: member_game.id,
-        user_id: member.id
-      )
-    end
-
-    it 'returns not found for another user game' do
-      sign_in_as member
-
-      expect {
-        post '/gekanator/question_suggestions', params: {
-          gekanator_game_id: game.id,
-          question_text: 'member question?',
-          answer: 'yes'
-        }
-      }.not_to change { GekanatorQuestionSuggestion.count }
-
-      expect(response).to have_http_status(:not_found)
-    end
-
-    it 'returns unauthorized without a user' do
-      expect {
-        post '/gekanator/question_suggestions', params: {
-          gekanator_game_id: game.id,
-          question_text: 'member question?',
-          answer: 'yes'
-        }
-      }.not_to change { GekanatorQuestionSuggestion.count }
-
-      expect(response).to have_http_status(:unauthorized)
-    end
-  end
-
-  describe 'GET /gekanator/games/:id/extra_questions' do
-    it 'returns at most two accepted user_suggested post_similarity questions without duplicates' do
-      sign_in_as admin
-
-      low = create_post_similarity_question!(
-        text: 'low?',
-        priority_weight: 1.0
-      )
-      high = create_post_similarity_question!(
-        text: 'high?',
-        priority_weight: 3.0
-      )
-      middle = create_post_similarity_question!(
-        text: 'middle?',
-        priority_weight: 2.0
-      )
-
-      get "/gekanator/games/#{game.id}/extra_questions"
-
-      expect(response).to have_http_status(:ok)
-      expect(json['questions'].length).to eq(2)
-      expect(json['questions'].map { _1['id'] }.uniq.length).to eq(2)
-      expect(json['questions'].map { _1['id'] }).to all(be_in([low.id, high.id, middle.id]))
-    end
-
-    it 'can return questions that already have an example for the correct post' do
-      sign_in_as admin
-
-      existing = create_post_similarity_question!(text: 'already learned?')
-
-      GekanatorQuestionExample.create!(
-        gekanator_question: existing,
-        post: correct_post,
-        user: admin,
-        gekanator_game: game,
-        answer: 'yes',
-        source: 'post_game_extra'
-      )
-
-      get "/gekanator/games/#{game.id}/extra_questions"
-
-      expect(response).to have_http_status(:ok)
-      expect(json['questions'].map { _1['id'] }).to include(existing.id)
-    end
-
-    it 'can return questions already asked in the game using snake_case question_id' do
-      sign_in_as admin
-
-      asked = create_post_similarity_question!(text: 'already asked?')
-      game.update!(
-        answers: [
-          {
-            'question_id' => "post-similarity:#{asked.id}",
-            'answer' => 'yes'
-          }
-        ]
-      )
-
-      get "/gekanator/games/#{game.id}/extra_questions"
-
-      expect(response).to have_http_status(:ok)
-      expect(json['questions'].map { _1['id'] }).to include(asked.id)
-    end
-
-    it 'can return questions already asked in the game using camelCase questionId' do
-      sign_in_as admin
-
-      asked = create_post_similarity_question!(text: 'already asked?')
-      game.update!(
-        answers: [
-          {
-            'questionId' => "post-similarity:#{asked.id}",
-            'answer' => 'yes'
-          }
-        ]
-      )
-
-      get "/gekanator/games/#{game.id}/extra_questions"
-
-      expect(response).to have_http_status(:ok)
-      expect(json['questions'].map { _1['id'] }).to include(asked.id)
-    end
-
-    it 'does not return non-accepted, non-user_suggested, or non-post_similarity questions' do
-      sign_in_as admin
-
-      accepted = create_post_similarity_question!(text: 'accepted?')
-      create_post_similarity_question!(text: 'disabled?', status: 'disabled')
-      create_post_similarity_question!(text: 'ai?', source: 'ai_generated')
-      GekanatorQuestion.create!(
-        text: 'tag?',
-        kind: 'tag',
-        source: 'user_suggested',
-        status: 'accepted',
-        priority_weight: 1.0,
-        condition: { type: 'tag', key: 'character:喜多郁代' }
-      )
-
-      get "/gekanator/games/#{game.id}/extra_questions"
-
-      expect(response).to have_http_status(:ok)
-      expect(json['questions'].map { _1['id'] }).to contain_exactly(accepted.id)
-    end
-
-    it 'allows a non-admin user to fetch extra questions for their own game' do
-      member_game = GekanatorGame.create!(
-        user: member,
-        guessed_post: guessed_post,
-        correct_post: correct_post,
-        won: false,
-        question_count: 1,
-        answers: [{ 'question_id' => 'tag:1', 'answer' => 'yes' }]
-      )
-      accepted = create_post_similarity_question!(text: 'accepted?')
-      sign_in_as member
-
-      get "/gekanator/games/#{member_game.id}/extra_questions"
-
-      expect(response).to have_http_status(:ok)
-      expect(json['questions'].map { _1['id'] }).to include(accepted.id)
-    end
-
-    it 'returns not found for another user game' do
-      sign_in_as member
-
-      get "/gekanator/games/#{game.id}/extra_questions"
-
-      expect(response).to have_http_status(:not_found)
-    end
-
-    it 'returns unauthorized without a user' do
-      get "/gekanator/games/#{game.id}/extra_questions"
-
-      expect(response).to have_http_status(:unauthorized)
-    end
-  end
-
-  describe 'POST /gekanator/games/:id/extra_question_answers' do
-    it 'creates examples for extra question answers' do
-      sign_in_as admin
-
-      question = create_post_similarity_question!(text: 'extra?')
-
-      expect {
-        post "/gekanator/games/#{game.id}/extra_question_answers", params: {
-          answers: [
-            {
-              question_id: question.id.to_s,
-              answer: 'partial'
-            }
-          ]
-        }
-      }.to change { GekanatorQuestionExample.count }.by(1)
-
-      expect(response).to have_http_status(:created)
-      expect(json).to include('count' => 1)
-
-      example = GekanatorQuestionExample.last
-      expect(example).to have_attributes(
-        gekanator_question_id: question.id,
-        post_id: correct_post.id,
-        user_id: admin.id,
-        gekanator_game_id: game.id,
-        answer: 'partial',
-        source: 'post_game_extra',
-        weight: 1.0
-      )
-    end
-
-    it 'updates an existing example for the same question, post, and user' do
-      sign_in_as admin
-
-      question = create_post_similarity_question!(text: 'extra?')
-      existing = GekanatorQuestionExample.create!(
-        gekanator_question: question,
-        post: correct_post,
-        user: admin,
-        answer: 'no',
-        source: 'post_game_extra',
-        weight: 1.0
-      )
-
-      expect {
-        post "/gekanator/games/#{game.id}/extra_question_answers", params: {
-          answers: [
-            {
-              question_id: question.id,
-              answer: 'yes'
-            }
-          ]
-        }
-      }.not_to change { GekanatorQuestionExample.count }
-
-      expect(response).to have_http_status(:created)
-      expect(existing.reload).to have_attributes(
-        answer: 'yes',
-        source: 'post_game_extra',
-        gekanator_game_id: game.id
-      )
-    end
-
-    it 'rejects missing questions' do
-      sign_in_as admin
-
-      expect {
-        post "/gekanator/games/#{game.id}/extra_question_answers", params: {
-          answers: [
-            {
-              question_id: 999_999_999,
-              answer: 'yes'
-            }
-          ]
-        }
-      }.not_to change { GekanatorQuestionExample.count }
-
-      expect(response).to have_http_status(:unprocessable_entity)
-    end
-
-    it 'rejects non-accepted questions' do
-      sign_in_as admin
-
-      question = create_post_similarity_question!(
-        text: 'disabled?',
-        status: 'disabled'
-      )
-
-      post "/gekanator/games/#{game.id}/extra_question_answers", params: {
-        answers: [
-          {
-            question_id: question.id,
-            answer: 'yes'
-          }
-        ]
-      }
-
-      expect(response).to have_http_status(:unprocessable_entity)
-    end
-
-    it 'rejects non-post_similarity questions' do
-      sign_in_as admin
-
-      question = GekanatorQuestion.create!(
-        text: 'tag?',
-        kind: 'tag',
-        source: 'user_suggested',
-        status: 'accepted',
-        priority_weight: 1.0,
-        condition: { type: 'tag', key: 'character:喜多郁代' }
-      )
-
-      post "/gekanator/games/#{game.id}/extra_question_answers", params: {
-        answers: [
-          {
-            question_id: question.id,
-            answer: 'yes'
-          }
-        ]
-      }
-
-      expect(response).to have_http_status(:unprocessable_entity)
-    end
-
-    it 'allows a non-admin user to answer extra questions for their own game' do
-      member_game = GekanatorGame.create!(
-        user: member,
-        guessed_post: guessed_post,
-        correct_post: correct_post,
-        won: false,
-        question_count: 1,
-        answers: [{ 'question_id' => 'tag:1', 'answer' => 'yes' }]
-      )
-      question = create_post_similarity_question!(text: 'extra?')
-      sign_in_as member
-
-      expect {
-        post "/gekanator/games/#{member_game.id}/extra_question_answers", params: {
-          answers: [
-            {
-              question_id: question.id,
-              answer: 'yes'
-            }
-          ]
-        }
-      }.to change { GekanatorQuestionExample.count }.by(1)
-
-      expect(response).to have_http_status(:created)
-      expect(GekanatorQuestionExample.last).to have_attributes(
-        user_id: member.id,
-        gekanator_game_id: member_game.id
-      )
-    end
-
-    it 'returns not found for another user game' do
-      question = create_post_similarity_question!(text: 'extra?')
-      sign_in_as member
-
-      expect {
-        post "/gekanator/games/#{game.id}/extra_question_answers", params: {
-          answers: [
-            {
-              question_id: question.id,
-              answer: 'yes'
-            }
-          ]
-        }
-      }.not_to change { GekanatorQuestionExample.count }
-
-      expect(response).to have_http_status(:not_found)
-    end
-
-    it 'returns unauthorized without a user' do
-      question = create_post_similarity_question!(text: 'extra?')
-
-      post "/gekanator/games/#{game.id}/extra_question_answers", params: {
-        answers: [
-          {
-            question_id: question.id,
-            answer: 'yes'
-          }
-        ]
-      }
-
-      expect(response).to have_http_status(:unauthorized)
-    end
-  end
-
-  describe 'GET /gekanator/questions' do
-    it 'returns accepted questions only and includes example_answers for post_similarity questions' do
-      sign_in_as admin
-
-      accepted = create_post_similarity_question!(text: 'accepted?')
-      create_post_similarity_question!(
-        text: 'disabled?',
-        status: 'disabled'
-      )
-
-      GekanatorQuestionExample.create!(
-        gekanator_question: accepted,
-        post: correct_post,
-        user: admin,
-        answer: 'yes',
-        source: 'initial_suggestion',
-        weight: 1.0
-      )
-
-      get '/gekanator/questions'
-
-      expect(response).to have_http_status(:ok)
-      expect(json['questions'].length).to eq(1)
-
-      question_json = json['questions'].first
-      expect(question_json).to include(
-        'id' => "post-similarity:#{accepted.id}",
-        'text' => 'accepted?',
-        'kind' => 'post_similarity',
-        'source' => 'user_suggested',
-        'priority_weight' => 1.2
-      )
-      expect(question_json['condition']).to include(
-        'type' => 'post-similarity',
-        'postId' => correct_post.id,
-        'answer' => 'yes',
-        'threshold' => 0.65
-      )
-      expect(question_json['example_answers']).to include(
-        correct_post.id.to_s => 'yes'
-      )
-    end
-
-    it 'aggregates example_answers by weight' do
-      sign_in_as admin
-
-      question = create_post_similarity_question!(text: 'weighted?')
-
-      GekanatorQuestionExample.create!(
-        gekanator_question: question,
-        post: other_post,
-        user: admin,
-        answer: 'yes',
-        source: 'post_game_extra',
-        weight: 1.0
-      )
-      GekanatorQuestionExample.create!(
-        gekanator_question: question,
-        post: other_post,
-        user: other_user,
-        answer: 'no',
-        source: 'post_game_extra',
-        weight: 2.0
-      )
-
-      get '/gekanator/questions'
-
-      expect(response).to have_http_status(:ok)
-      question_json = json['questions'].find { _1['id'] == "post-similarity:#{question.id}" }
-      expect(question_json['example_answers']).to include(
-        other_post.id.to_s => 'no'
-      )
-    end
-
-    it 'normalizes legacy title length questions' do
-      sign_in_as admin
-
-      GekanatorQuestion.create!(
-        text: '題名が長めの投稿?',
-        kind: 'title',
-        source: 'admin_curated',
-        status: 'accepted',
-        priority_weight: 1.0,
-        condition: {
-          type: 'title-length-greater-than',
-          length: 20
-        },
-        created_by: admin
-      )
-
-      get '/gekanator/questions'
-
-      expect(response).to have_http_status(:ok)
-      question_json = json['questions'].find { _1['id'] == 'title:length-at-least:21' }
-      expect(question_json).to include(
-        'text' => 'タイトルは 21 文字以上?',
-        'kind' => 'title'
-      )
-      expect(question_json['condition']).to include(
-        'type' => 'title-length-at-least',
-        'length' => 21
-      )
-    end
-
-    it 'returns title-contains questions without authentication' do
-      GekanatorQuestion.create!(
-        text: '題名に「結束バンド」が含まれる?',
-        kind: 'title',
-        source: 'ai_generated',
-        status: 'accepted',
-        priority_weight: 0.95,
-        condition: {
-          type: 'title-contains',
-          text: '結束バンド'
-        },
-        created_by: admin
-      )
-
-      get '/gekanator/questions'
-
-      expect(response).to have_http_status(:ok)
-      question_json = json['questions'].find { _1['id'] == 'title:contains:結束バンド' }
-      expect(question_json).to include(
-        'text' => '題名に「結束バンド」が含まれる?',
-        'kind' => 'title'
-      )
-      expect(question_json['condition']).to include(
-        'type' => 'title-contains',
-        'text' => '結束バンド'
-      )
-    end
-  end
-end

backend/spec/requests/materials_spec.rb

@@ -141,21 +141,16 @@ RSpec.describe 'Materials API', type: :request do
     context 'when logged in' do
       before { sign_in_as(guest_user) }
 
-      it 'returns 422 when tag is blank' do
+      it 'returns 400 when tag is blank' do
         post '/materials', params: { tag: '   ', file: dummy_upload }
 
-        expect(response).to have_http_status(:unprocessable_entity)
+        expect(response).to have_http_status(:bad_request)
-        expect(json.fetch('errors')).to include(
-            'tag' => ['タグは必須です．'])
       end
 
-      it 'returns 422 when both file and url are blank' do
+      it 'returns 400 when both file and url are blank' do
         post '/materials', params: { tag: 'material_create_blank' }
 
-        expect(response).to have_http_status(:unprocessable_entity)
+        expect(response).to have_http_status(:bad_request)
-        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 'creates a material with an attached file' do
@@ -266,26 +261,21 @@ RSpec.describe 'Materials API', type: :request do
         expect(response).to have_http_status(:not_found)
       end
 
-      it 'returns 422 when tag is blank' do
+      it 'returns 400 when tag is blank' do
         put "/materials/#{ material.id }", params: {
           tag: '   ',
           file: dummy_upload
         }
 
-        expect(response).to have_http_status(:unprocessable_entity)
+        expect(response).to have_http_status(:bad_request)
-        expect(json.fetch('errors')).to include(
-            'tag' => ['タグは必須です．'])
       end
 
-      it 'returns 422 when both file and url are blank' do
+      it 'returns 400 when both file and url are blank' do
         put "/materials/#{ material.id }", params: {
           tag: 'material_update_no_payload'
         }
 
-        expect(response).to have_http_status(:unprocessable_entity)
+        expect(response).to have_http_status(:bad_request)
-        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

backend/spec/requests/nico_tags_spec.rb

@@ -3,68 +3,12 @@ require 'rails_helper'
 
 RSpec.describe 'NicoTags', type: :request do
   describe 'GET /tags/nico' do
-    it 'returns paginated tags and total count' do
+    it 'returns tags and next_cursor when overflowing limit' do
-      create_list(:tag, 3, :nico)
+      create_list(:tag, 21, :nico)
-
+      get '/tags/nico', params: { limit: 20 }
-      get '/tags/nico', params: { page: 2, limit: 2 }
-
       expect(response).to have_http_status(:ok)
-      expect(json['tags'].size).to eq(1)
+      expect(json['tags'].size).to eq(20)
-      expect(json['count']).to eq(3)
+      expect(json['next_cursor']).to be_present
-    end
-
-    it 'filters by nico tag name, linked tag name, and link status' do
-      linked = create(:tag, :nico)
-      linked.tag_name.update!(name: 'nico:search_linked')
-      unlinked = create(:tag, :nico)
-      unlinked.tag_name.update!(name: 'nico:search_unlinked')
-      other = create(:tag, :nico)
-      other.tag_name.update!(name: 'nico:other')
-      destination = create(:tag, :general)
-      destination.tag_name.update!(name: 'destination_search')
-      NicoTagRelation.create!(nico_tag: linked, tag: destination)
-      NicoTagRelation.create!(nico_tag: other, tag: create(:tag, :general))
-
-      get '/tags/nico', params: {
-        name: 'search_',
-        linked_tag: 'destination_',
-        link_status: 'linked'
-      }
-
-      expect(response).to have_http_status(:ok)
-      expect(json['count']).to eq(1)
-      expect(json.fetch('tags').map { |tag| tag['id'] }).to eq([linked.id])
-
-      get '/tags/nico', params: { name: 'search_', link_status: 'unlinked' }
-
-      expect(json['count']).to eq(1)
-      expect(json.fetch('tags').map { |tag| tag['id'] }).to eq([unlinked.id])
-    end
-
-    it 'sorts by name and timestamps' do
-      older = create(:tag, :nico)
-      older.tag_name.update!(name: 'nico:a')
-      older.update_columns(created_at: 2.days.ago)
-      newer = create(:tag, :nico)
-      newer.tag_name.update!(name: 'nico:b')
-      newer.update_columns(created_at: 1.day.ago)
-      older_post_tag =
-        PostTag.create!(post: Post.create!(url: 'https://example.com/nico-older'), tag: older)
-      older_post_tag.update_columns(created_at: 1.hour.ago)
-      newer_post_tag =
-        PostTag.create!(post: Post.create!(url: 'https://example.com/nico-newer'), tag: newer)
-      newer_post_tag.update_columns(created_at: 2.hours.ago)
-
-      get '/tags/nico', params: { order: 'name:desc' }
-      expect(json.fetch('tags').map { |tag| tag['id'] }).to eq([newer.id, older.id])
-
-      get '/tags/nico', params: { order: 'created_at:asc' }
-      expect(json.fetch('tags').map { |tag| tag['id'] }).to eq([older.id, newer.id])
-
-      get '/tags/nico', params: { order: 'updated_at:desc' }
-      expect(json.fetch('tags').map { |tag| tag['id'] }).to eq([older.id, newer.id])
-      expect(Time.zone.parse(json.fetch('tags').first.fetch('recent_post_tag_created_at')))
-        .to be_within(1.second).of(older_post_tag.created_at)
     end
   end
 
@@ -131,7 +75,7 @@ RSpec.describe 'NicoTags', type: :request do
       expect(versions.last.created_by_user_id).to eq(admin.id)
     end
 
-    it 'returns 422 when linked tag normalises to nico tag' do
+    it '400 when linked tag normalises to nico tag' do
       sign_in_as(member)
 
       other_nico = create(:tag, :nico, name: 'nico:linked_ng')
@@ -143,37 +87,7 @@ RSpec.describe 'NicoTags', type: :request do
         patch "/tags/nico/#{nico_tag.id}", params: { tags: 'linked_ng_alias' }
       }.not_to change(NicoTagVersion, :count)
 
-      expect(response).to have_http_status(:unprocessable_entity)
+      expect(response).to have_http_status(:bad_request)
-      expect(json.fetch('errors')).to include(
-          'tags' => ['ニコニコ・タグ同士は連携できません．'])
-    end
-
-    it 'returns the tags field error when a nico tag is specified directly' do
-      sign_in_as(member)
-
-      patch "/tags/nico/#{nico_tag.id}", params: { tags: 'nico:linked_ng' }
-
-      expect(response).to have_http_status(:unprocessable_entity)
-      expect(json.fetch('errors')).to include(
-          'tags' => ['ニコニコ・タグ同士は連携できません．'])
-    end
-
-    it 'returns tag name validation errors on the tags field and rolls back created tags' do
-      sign_in_as(member)
-      TagNameSanitisationRule.create!(
-        priority: 1,
-        source_pattern: 'invalid',
-        replacement: 'valid'
-      )
-      nico_tag
-
-      expect {
-        patch "/tags/nico/#{nico_tag.id}", params: { tags: 'created_first invalid' }
-      }.not_to change(TagName, :count)
-
-      expect(response).to have_http_status(:unprocessable_entity)
-      expect(json.fetch('errors').fetch('tags')).to include(
-          a_string_including('タグ名 “invalid”:', '名前に使用できない文字が含まれてゐます．'))
     end
   end
 end

backend/spec/requests/posts_spec.rb

@@ -57,23 +57,6 @@ RSpec.describe 'Posts API', type: :request do
     post_write_params({ base_version_no: base_version.version_no }.merge(params))
   end
 
-  def count_sql_queries
-    count = 0
-
-    callback = lambda do |_name, _started, _finished, _id, payload|
-      next if payload[:cached]
-      next if ['SCHEMA', 'TRANSACTION'].include?(payload[:name])
-
-      count += 1
-    end
-
-    ActiveSupport::Notifications.subscribed(callback, 'sql.active_record') do
-      yield
-    end
-
-    count
-  end
-
   let!(:tag_name) { TagName.create!(name: 'spec_tag') }
   let!(:tag)      { Tag.create!(tag_name: tag_name, category: :general) }
 
@@ -575,59 +558,6 @@ RSpec.describe 'Posts API', type: :request do
           expect(sibling_ids).to include(sibling_post.id)
         end
       end
-
-      it 'does not issue a query per tag or related post' do
-        user = create_member_user!
-
-        tags =
-            15.times.map do |i|
-              tag_name = TagName.create!(name: "show_query_tag_#{ i }")
-              tag = Tag.create!(tag_name:, category: :general)
-              TagName.create!(name: "show_query_alias_#{ i }", canonical: tag_name)
-              PostTag.create!(post: post_record, tag:)
-              tag
-            end
-
-        tags.each_cons(2) do |parent_tag, child_tag|
-          TagImplication.create!(parent_tag:, tag: child_tag)
-        end
-
-        parent_post = Post.create!(
-          title: 'query parent post',
-          url: 'https://example.com/query-parent-post'
-        )
-        sibling_post = Post.create!(
-          title: 'query sibling post',
-          url: 'https://example.com/query-sibling-post'
-        )
-        child_post = Post.create!(
-          title: 'query child post',
-          url: 'https://example.com/query-child-post'
-        )
-
-        PostImplication.create!(post: post_record, parent_post:)
-        PostImplication.create!(post: sibling_post, parent_post:)
-        PostImplication.create!(post: child_post, parent_post: post_record)
-
-        20.times do |i|
-          related_post = Post.create!(
-            title: "query related post #{ i }",
-            url: "https://example.com/query-related-post-#{ i }"
-          )
-          PostSimilarity.create!(post: post_record,
-                                 target_post: related_post,
-                                 cos: 1.0 - (i / 100.0))
-        end
-
-        query_count =
-            count_sql_queries do
-              get "/posts/#{ post_record.id }",
-                  headers: { 'X-Transfer-Code' => user.inheritance_code }
-            end
-
-        expect(response).to have_http_status(:ok)
-        expect(query_count).to be <= 45
-      end
     end
 
     context 'when post does not exist' do
@@ -704,7 +634,7 @@ RSpec.describe 'Posts API', type: :request do
             category: :nico)
       end
 
-      it 'returns 422 with tag field errors' do
+      it 'return 400' do
         sign_in_as(member)
 
         post '/posts', params: post_write_params(
@@ -714,13 +644,7 @@ RSpec.describe 'Posts API', type: :request do
           thumbnail: dummy_upload
         )
 
-        expect(response).to have_http_status(:unprocessable_entity), response.body
+        expect(response).to have_http_status(:bad_request), response.body
-        expect(json).to include(
-            'type' => 'validation_error',
-            'message' => '入力内容を確認してください．',
-            'base_errors' => [])
-        expect(json.fetch('errors')).to include(
-            'tags' => ['ニコニコ・タグは直接指定できません．'])
       end
     end
 
@@ -937,7 +861,7 @@ RSpec.describe 'Posts API', type: :request do
             category: :nico)
       end
 
-      it 'returns 422 with tag field errors' do
+      it 'return 400' do
         sign_in_as(member)
 
         put "/posts/#{post_record.id}", params: post_update_params(
@@ -945,13 +869,7 @@ RSpec.describe 'Posts API', type: :request do
             title: 'updated title',
             tags: 'nico:nico_tag')
 
-        expect(response).to have_http_status(:unprocessable_entity), response.body
+        expect(response).to have_http_status(:bad_request), response.body
-        expect(json).to include(
-            'type' => 'validation_error',
-            'message' => '入力内容を確認してください．',
-            'base_errors' => [])
-        expect(json.fetch('errors')).to include(
-            'tags' => ['ニコニコ・タグは直接指定できません．'])
       end
     end
 

backend/spec/requests/tags_deerjikists_spec.rb

@@ -275,30 +275,6 @@ RSpec.describe 'Tags deerjikists API', type: :request do
         end
       end
 
-      context 'when a row is invalid' do
-        let(:payload) do
-          [
-            { platform: '', code: code1 },
-          ]
-        end
-
-        it 'returns 422 with indexed field errors and does not replace existing deerjikists' do
-          Deerjikist.create!(platform: platform1, code: code1, tag: tag)
-
-          expect {
-            do_request
-          }.not_to change { Deerjikist.where(tag: tag).map { |d| [d.platform, d.code] } }
-
-          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．',
-              'base_errors' => [])
-          expect(json.fetch('errors')).to include(
-              'deerjikists.0.platform' => [be_present])
-        end
-      end
-
       context 'when youtube code is handle' do
         let(:channel_id) { 'UCabcdefghijklmnopqrstuv' }
         let(:payload) do

backend/spec/requests/theatre_comments_spec.rb

@@ -80,26 +80,6 @@ RSpec.describe 'TheatreComments', type: :request do
       expect(response).to have_http_status(:ok)
       expect(response.parsed_body.map { |row| row['no'] }).to eq([3, 2, 1])
     end
-
-    it '削除済みコメントは deleted として返し、本文を隠す' do
-      comment_2.discard!
-
-      get "/theatres/#{theatre.id}/comments", params: { no_gt: 1 }
-
-      expect(response).to have_http_status(:ok)
-
-      deleted_comment = response.parsed_body.find { _1['no'] == 2 }
-      expect(deleted_comment).to include(
-        'deleted' => true,
-        'content' => nil
-      )
-
-      visible_comment = response.parsed_body.find { _1['no'] == 3 }
-      expect(visible_comment).to include(
-        'deleted' => false,
-        'content' => 'third comment'
-      )
-    end
   end
 
   describe 'POST /theatres/:theatre_id/comments' do
@@ -167,44 +147,4 @@ RSpec.describe 'TheatreComments', type: :request do
       })
     end
   end
-
-  describe 'DELETE /theatres/:theatre_id/comments/:id' do
-    let(:theatre) { create(:theatre) }
-    let(:alice) { create(:user, name: 'Alice') }
-    let(:bob) { create(:user, name: 'Bob') }
-    let!(:comment) do
-      create(
-        :theatre_comment,
-        theatre: theatre,
-        no: 1,
-        user: alice,
-        content: 'delete target'
-      )
-    end
-
-    it 'returns 401 when not logged in' do
-      delete "/theatres/#{theatre.id}/comments/#{comment.no}"
-
-      expect(response).to have_http_status(:unauthorized)
-      expect(comment.reload.discarded?).to eq(false)
-    end
-
-    it 'allows the comment owner to delete it' do
-      sign_in_as(alice)
-
-      delete "/theatres/#{theatre.id}/comments/#{comment.no}"
-
-      expect(response).to have_http_status(:no_content)
-      expect(comment.reload.discarded?).to eq(true)
-    end
-
-    it 'returns 403 when another user tries to delete it' do
-      sign_in_as(bob)
-
-      delete "/theatres/#{theatre.id}/comments/#{comment.no}"
-
-      expect(response).to have_http_status(:forbidden)
-      expect(comment.reload.discarded?).to eq(false)
-    end
-  end
 end

backend/spec/requests/theatre_programmes_spec.rb

@@ -1,38 +0,0 @@
-require 'rails_helper'
-
-RSpec.describe 'TheatreProgrammes', type: :request do
-  describe 'GET /theatres/:theatre_id/programmes' do
-    let(:theatre) { create(:theatre) }
-    let(:other_theatre) { create(:theatre) }
-    let(:post_1) { Post.create!(title: 'first', url: 'https://www.nicovideo.jp/watch/sm1') }
-    let(:post_2) { Post.create!(title: 'second', url: 'https://www.nicovideo.jp/watch/sm2') }
-    let(:other_post) { Post.create!(title: 'other', url: 'https://www.nicovideo.jp/watch/sm3') }
-
-    before do
-      TheatreProgramme.create!(theatre:, position: 1, post: post_1, created_at: 2.minutes.ago)
-      TheatreProgramme.create!(theatre:, position: 2, post: post_2, created_at: 1.minute.ago)
-      TheatreProgramme.create!(
-        theatre: other_theatre,
-        position: 1,
-        post: other_post,
-        created_at: 1.minute.ago
-      )
-    end
-
-    it 'returns programmes for the theatre in descending position with post json' do
-      get "/theatres/#{theatre.id}/programmes"
-
-      expect(response).to have_http_status(:ok)
-      expect(json.map { _1['position'] }).to eq([2, 1])
-      expect(json.map { _1.dig('post', 'title') }).to eq(['second', 'first'])
-      expect(json.first['post']).to include('id' => post_2.id, 'url' => post_2.url)
-    end
-
-    it 'filters programmes by position_gt' do
-      get "/theatres/#{theatre.id}/programmes", params: { position_gt: 1 }
-
-      expect(response).to have_http_status(:ok)
-      expect(json.map { _1['position'] }).to eq([2])
-    end
-  end
-end

backend/spec/requests/theatres_spec.rb

@@ -14,24 +14,10 @@ RSpec.describe 'Theatres API', type: :request do
   let(:member) { create(:user, :member, name: 'member user') }
   let(:other_user) { create(:user, :member, name: 'other user') }
 
-  let!(:niconico_post) do
-    Post.create!(
-      title: 'niconico post',
-      url: 'https://www.nicovideo.jp/watch/sm123'
-    )
-  end
-
-  let!(:second_niconico_post) do
-    Post.create!(
-      title: 'second niconico post',
-      url: 'https://www.nicovideo.jp/watch/sm456'
-    )
-  end
-
   let!(:youtube_post) do
     Post.create!(
       title: 'youtube post',
-      url: 'https://www.youtube.com/watch?v=yt123'
+      url: 'https://www.youtube.com/watch?v=spec123'
     )
   end
 
@@ -134,8 +120,7 @@ RSpec.describe 'Theatres API', type: :request do
         expect(json).to include(
           'host_flg' => true,
           'post_id' => nil,
-          'post_started_at' => nil,
+          'post_started_at' => nil
-          'post_elapsed_ms' => nil
         )
 
         expect(json.fetch('watching_users')).to contain_exactly(
@@ -192,8 +177,7 @@ RSpec.describe 'Theatres API', type: :request do
         expect(json).to include(
           'host_flg' => false,
           'post_id' => nil,
-          'post_started_at' => nil,
+          'post_started_at' => nil
-          'post_elapsed_ms' => nil
         )
 
         expect(json.fetch('watching_users')).to contain_exactly(
@@ -220,7 +204,7 @@ RSpec.describe 'Theatres API', type: :request do
         )
         theatre.update!(
           host_user: other_user,
-          current_post: niconico_post,
+          current_post: youtube_post,
           current_post_started_at: started_at
         )
         sign_in_as(member)
@@ -236,11 +220,9 @@ RSpec.describe 'Theatres API', type: :request do
         expect(theatre.host_user_id).to eq(member.id)
 
         expect(json['host_flg']).to eq(true)
-        expect(json['post_id']).to eq(niconico_post.id)
+        expect(json['post_id']).to eq(youtube_post.id)
         expect(Time.zone.parse(json['post_started_at']))
           .to be_within(1.second).of(started_at)
-        expect(json['post_elapsed_ms'])
-          .to be_within(1_000).of(120_000)
       end
     end
   end
@@ -291,36 +273,16 @@ RSpec.describe 'Theatres API', type: :request do
       it 'sets current_post to an eligible post and updates current_post_started_at' do
         expect { do_request }
           .to change { theatre.reload.current_post_id }
+          .from(nil).to(youtube_post.id)
 
         expect(response).to have_http_status(:no_content)
-        expect([niconico_post.id, second_niconico_post.id, youtube_post.id])
-          .to include(theatre.reload.current_post_id)
         expect(theatre.reload.current_post_started_at)
           .to be_within(1.second).of(Time.current)
-        expect(theatre.programmes.count).to eq(1)
-      end
-    end
-
-    context 'when only a YouTube post is eligible' do
-      before do
-        niconico_post.destroy!
-        second_niconico_post.destroy!
-        theatre.update!(host_user: member)
-        sign_in_as(member)
-      end
-
-      it 'sets current_post to the YouTube post' do
-        do_request
-
-        expect(response).to have_http_status(:no_content)
-        expect(theatre.reload.current_post_id).to eq(youtube_post.id)
       end
     end
 
     context 'when current user is host and no eligible post exists' do
       before do
-        niconico_post.destroy!
-        second_niconico_post.destroy!
         youtube_post.destroy!
         theatre.update!(
           host_user: member,
@@ -337,189 +299,9 @@ RSpec.describe 'Theatres API', type: :request do
 
         theatre.reload
         expect(theatre.current_post_id).to be_nil
-        expect(theatre.current_post_started_at).to be_nil
+        expect(theatre.current_post_started_at)
+          .to be_within(1.second).of(Time.current)
       end
     end
   end
-
-  describe 'PUT /theatres/:id/skip_vote' do
-    subject(:do_request) do
-      put "/theatres/#{theatre.id}/skip_vote", params: { post_id: requested_post_id }
-    end
-
-    let(:third_user) { create(:user, :member, name: 'third user') }
-    let(:requested_post_id) { niconico_post.id }
-
-    before do
-      theatre.update!(current_post: niconico_post, current_post_started_at: 10.seconds.ago)
-      [member, other_user, third_user].each do |user|
-        TheatreWatchingUser.create!(
-          theatre:,
-          user:,
-          expires_at: 10.seconds.from_now
-        )
-      end
-    end
-
-    it 'returns 401 when not logged in' do
-      sign_out
-
-      expect { do_request }.not_to change(TheatreSkipVote, :count)
-
-      expect(response).to have_http_status(:unauthorized)
-    end
-
-    it 'returns 422 when post_id is invalid' do
-      sign_in_as(member)
-
-      expect {
-        put "/theatres/#{theatre.id}/skip_vote", params: { post_id: 'invalid' }
-      }.not_to change(TheatreSkipVote, :count)
-
-      expect(response).to have_http_status(:unprocessable_entity)
-    end
-
-    it 'records a vote and returns the current vote status before majority' do
-      sign_in_as(member)
-
-      expect { do_request }.to change(TheatreSkipVote, :count).by(1)
-
-      expect(response).to have_http_status(:ok)
-      expect(json['skipped']).to eq(false)
-      expect(json['post_id']).to eq(niconico_post.id)
-      expect(json['skip_vote']).to include(
-        'votes_count' => 1,
-        'required_count' => 2,
-        'watching_users_count' => 3,
-        'voted' => true
-      )
-    end
-
-    it 'finalizes skip when votes reach majority and stores voters and tag snapshots' do
-      tag = create(:tag, name: 'skip-target')
-      PostTag.create!(post: niconico_post, tag:)
-
-      TheatreSkipVote.create!(theatre:, post: niconico_post, user: member)
-      sign_in_as(other_user)
-
-      expect { do_request }
-        .to change(TheatreSkipEvent, :count).by(1)
-        .and change(TheatreSkipEventVoter, :count).by(2)
-        .and change(TheatreSkipEventTag, :count).by(1)
-
-      expect(response).to have_http_status(:ok)
-      expect(json['skipped']).to eq(true)
-      expect([second_niconico_post.id, youtube_post.id]).to include(json['post_id'])
-
-      event = TheatreSkipEvent.last
-      expect(event.post).to eq(niconico_post)
-      expect(event.users).to contain_exactly(member, other_user)
-      expect(event.tags).to contain_exactly(tag)
-      expect(TheatreSkipVote.where(theatre:, post: niconico_post)).to be_empty
-    end
-
-    it 'does not record a vote when requested post is no longer current' do
-      theatre.update!(current_post: second_niconico_post)
-      sign_in_as(member)
-
-      expect { do_request }.not_to change(TheatreSkipVote, :count)
-
-      expect(response).to have_http_status(:conflict)
-      expect(json['post_id']).to eq(second_niconico_post.id)
-      expect(json['skip_vote']).to include(
-        'votes_count' => 0,
-        'voted' => false
-      )
-    end
-  end
-
-  describe 'DELETE /theatres/:id/skip_vote' do
-    let(:requested_post_id) { niconico_post.id }
-
-    before do
-      theatre.update!(current_post: niconico_post, current_post_started_at: 10.seconds.ago)
-      TheatreWatchingUser.create!(theatre:, user: member, expires_at: 10.seconds.from_now)
-      TheatreSkipVote.create!(theatre:, post: niconico_post, user: member)
-      sign_in_as(member)
-    end
-
-    it 'removes the current user vote' do
-      expect {
-        delete "/theatres/#{theatre.id}/skip_vote", params: { post_id: requested_post_id }
-      }.to change(TheatreSkipVote, :count).by(-1)
-
-      expect(response).to have_http_status(:ok)
-      expect(json['skip_vote']).to include(
-        'votes_count' => 0,
-        'required_count' => 1,
-        'watching_users_count' => 1,
-        'voted' => false
-      )
-    end
-
-    it 'does not remove a vote when requested post is no longer current' do
-      theatre.update!(current_post: second_niconico_post)
-
-      expect {
-        delete "/theatres/#{theatre.id}/skip_vote", params: { post_id: requested_post_id }
-      }.not_to change(TheatreSkipVote, :count)
-
-      expect(response).to have_http_status(:conflict)
-      expect(json['post_id']).to eq(second_niconico_post.id)
-    end
-  end
-
-  describe 'GET /theatres/:id/skip_events' do
-    before do
-      sign_in_as(member)
-    end
-
-    it 'does not expose skip voters' do
-      event = TheatreSkipEvent.create!(
-        theatre:,
-        post: niconico_post,
-        skipped_by_user: member,
-        created_at: Time.current
-      )
-      TheatreSkipEventVoter.create!(theatre_skip_event: event, user: member)
-
-      get "/theatres/#{theatre.id}/skip_events"
-
-      expect(response).to have_http_status(:ok)
-      expect(json.first).to include(
-        'id' => event.id,
-        'theatre_id' => theatre.id
-      )
-      expect(json.first).not_to have_key('voters')
-      expect(json.first).not_to have_key('skipped_by_user')
-    end
-  end
-
-  describe 'GET /theatres/:id/post_selection_weights' do
-    before do
-      theatre.update!(current_post: niconico_post)
-      TheatreWatchingUser.create!(theatre:, user: member, expires_at: 10.seconds.from_now)
-      sign_in_as(member)
-    end
-
-    it 'returns tag penalties and candidate weights for the current watchers' do
-      tag = create(:tag, name: 'heavy-tag')
-      PostTag.create!(post: second_niconico_post, tag:)
-      event = TheatreSkipEvent.create!(
-        theatre:,
-        post: niconico_post,
-        skipped_by_user: member,
-        created_at: Time.current
-      )
-      TheatreSkipEventVoter.create!(theatre_skip_event: event, user: member)
-      TheatreSkipEventTag.create!(theatre_skip_event: event, tag:)
-
-      get "/theatres/#{theatre.id}/post_selection_weights"
-
-      expect(response).to have_http_status(:ok)
-      expect(json['tag_penalties'].first['penalty']).to eq(1)
-      expect(json['lightest_posts'].first['post']['id']).to eq(second_niconico_post.id)
-      expect(json['lightest_posts'].first['penalty']).to eq(1)
-    end
-  end
 end

backend/spec/requests/users_spec.rb

@@ -90,14 +90,12 @@ RSpec.describe 'Users', type: :request do
       expect(response).to have_http_status(:unauthorized)
     end
 
-    it 'returns 422 when name is blank' do
+    it 'returns 400 when name is blank' do
       put "/users/#{user.id}",
           params: { name: '   ' },
           headers: auth_headers(user)
 
-      expect(response).to have_http_status(:unprocessable_entity)
+      expect(response).to have_http_status(:bad_request)
-      expect(json.fetch('errors')).to include(
-          'name' => ['名前は必須です．'])
     end
 
     it 'updates name and returns user slice' do

backend/spec/services/gekanator/question_suggestion_ai_converter_spec.rb

@@ -1,112 +0,0 @@
-require 'rails_helper'
-
-RSpec.describe Gekanator::QuestionSuggestionAiConverter do
-  let(:user) { create(:user, :member) }
-  let(:guessed_post) { Post.create!(title: 'guess', url: 'https://example.com/guess') }
-  let(:correct_post) { Post.create!(title: 'correct', url: 'https://example.com/correct') }
-  let(:game) do
-    GekanatorGame.create!(
-      user: user,
-      guessed_post: guessed_post,
-      correct_post: correct_post,
-      won: false,
-      question_count: 1,
-      answers: [{ 'question_id' => 'tag:1', 'answer' => 'yes' }]
-    )
-  end
-
-  def create_suggestion!(question_text:, answer: 'yes')
-    GekanatorQuestionSuggestion.create!(
-      gekanator_game: game,
-      user: user,
-      question_text: question_text,
-      answer: answer
-    )
-  end
-
-  it 'converts title-contains suggestions to pending ai-generated questions' do
-    suggestion = create_suggestion!(question_text: '題名に「結束バンド」が含まれる?')
-
-    expect {
-      described_class.call(suggestion: suggestion, user: user)
-    }.to change { GekanatorQuestion.count }.by(1)
-      .and change { GekanatorAiRun.count }.by(1)
-
-    question = GekanatorQuestion.last
-    expect(question).to have_attributes(
-      text: '題名に「結束バンド」が含まれる?',
-      kind: 'title',
-      source: 'ai_generated',
-      status: 'pending',
-      priority_weight: 0.95,
-      gekanator_question_suggestion_id: suggestion.id,
-      created_by_id: user.id
-    )
-    expect(question.condition).to include(
-      'type' => 'title-contains',
-      'text' => '結束バンド'
-    )
-    expect(GekanatorAiRun.last).to have_attributes(
-      gekanator_question_suggestion_id: suggestion.id,
-      model: 'heuristic_converter_v1',
-      status: 'succeeded'
-    )
-  end
-
-  it 'converts concrete non-unknown suggestions to post-similarity questions' do
-    suggestion = create_suggestion!(
-      question_text: '喜多ちゃんが泣いてる?',
-      answer: 'partial'
-    )
-
-    question = described_class.call(suggestion: suggestion, user: user)
-
-    expect(question).to have_attributes(
-      text: '喜多ちゃんが泣いてる?',
-      kind: 'post_similarity',
-      source: 'ai_generated',
-      status: 'pending',
-      priority_weight: 1.0
-    )
-    expect(question.condition).to include(
-      'type' => 'post-similarity',
-      'postId' => correct_post.id,
-      'answer' => 'partial',
-      'threshold' => 0.65
-    )
-  end
-
-  it 'records a failed run when the suggestion cannot be converted' do
-    suggestion = create_suggestion!(
-      question_text: 'よく分からない質問?',
-      answer: 'unknown'
-    )
-
-    expect {
-      expect(described_class.call(suggestion: suggestion, user: user)).to be_nil
-    }.not_to change { GekanatorQuestion.count }
-
-    expect(GekanatorAiRun.last).to have_attributes(
-      gekanator_question_suggestion_id: suggestion.id,
-      status: 'failed'
-    )
-  end
-
-  it 'returns an existing generated question without creating a duplicate run' do
-    suggestion = create_suggestion!(question_text: 'タイトルは 10 文字以上?')
-    existing = GekanatorQuestion.create!(
-      text: 'タイトルは 10 文字以上?',
-      kind: 'title',
-      source: 'ai_generated',
-      status: 'pending',
-      priority_weight: 0.95,
-      condition: { type: 'title-length-at-least', length: 10 },
-      gekanator_question_suggestion: suggestion,
-      created_by: user
-    )
-
-    expect {
-      expect(described_class.call(suggestion: suggestion, user: user)).to eq(existing)
-    }.not_to change { GekanatorAiRun.count }
-  end
-end

frontend/AGENTS.md

@@ -4,8 +4,7 @@
 
 These rules apply to work under `frontend/`.
 
-This is a Vite + React + TypeScript app using TanStack Query, Tailwind CSS,
+This is a Vite + React + TypeScript app using TanStack Query, Tailwind CSS, Framer Motion, Radix UI-style components, MDX, and Zustand.
-Framer Motion, Radix UI-style components, MDX, and Zustand.
 
 ## Commands
 
@@ -18,11 +17,9 @@ npm run lint
 npm run preview
 ```
 
-`npm run build` runs `tsc -b && vite build`, and `postbuild` runs
+`npm run build` runs `tsc -b && vite build`, and `postbuild` runs `node scripts/generate-sitemap.js`.
-`node scripts/generate-sitemap.js`.
 
-There is currently no `test` script in `package.json`. Do not run or report
+There is currently no `test` script in `package.json`. Do not run or report `npm test` unless a test script is added.
-`npm test` unless a test script is added.
 
 After frontend changes, run:
 
@@ -33,43 +30,20 @@ npm run lint
 
 If either 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.
-
 ## TypeScript
 
-- TypeScript is strict. `tsconfig.app.json` enables `strict`,
+- TypeScript is strict. `tsconfig.app.json` enables `strict`, `noUnusedLocals`, `noUnusedParameters`, `erasableSyntaxOnly`, `noFallthroughCasesInSwitch`, and `noUncheckedSideEffectImports`.
-  `noUnusedLocals`, `noUnusedParameters`, `erasableSyntaxOnly`,
-  `noFallthroughCasesInSwitch`, and `noUncheckedSideEffectImports`.
 - Keep types explicit at module boundaries, API helpers, and exported utilities.
 - Use `import type` for type-only imports.
 - Prefer existing shared types from `src/types.ts` before adding local duplicate types.
-- Preserve the repository's existing spacing style in TypeScript, including
+- Preserve the repository's existing spacing style in TypeScript, including GNU-style spacing before call parentheses where it is already used.
-  GNU-style spacing before call parentheses where it is already used.
 - Prefer single quotes for strings unless interpolation or escaping makes double quotes better.
-- Never write a TypeScript or TSX line longer than 99 characters.
-- Aim to keep TypeScript and TSX lines within 79 characters where practical.
-- Use 4-space logical indentation in TypeScript and TSX.
-- For arrays, never put whitespace or a line break immediately before `]`.
-- Keep the first element on the same line as `[` by default.
-- If an array would exceed the line limit, break after `[` and indent
-  elements by 4 spaces.
-- In TypeScript and TSX only, replace every leading run of 8 spaces with a tab
-  to reduce bytes.
-- Treat one leading tab as exactly equivalent to 8 leading spaces.
-- Use tabs only for leading indentation. Never replace spaces that occur after
-  a non-space character on the same line.
 
 ## React
 
 - Use function components.
-- Existing page components commonly export an anonymous function satisfying
+- Existing page components commonly export an anonymous function satisfying `FC`; match nearby file style when editing.
-  `FC`; match nearby file style when editing.
 - React hooks must be called unconditionally and at the top level of components or custom hooks.
-- Gate editing and other privileged controls with shared permission helpers
-  such as `canEditContent`, instead of showing controls and relying only on a
-  later API failure.
 - Keep page-level components under `src/pages`.
 - Keep shared and feature components under `src/components`.
 - Use `react-router-dom` route params and navigation patterns already present in `src/App.tsx`.
@@ -78,23 +52,17 @@ pass or the remaining failure is clearly blocked.
 ## TanStack Query
 
 - Use `@tanstack/react-query` for server state.
-- Query keys should come from `src/lib/queryKeys.ts`; add key builders there
+- Query keys should come from `src/lib/queryKeys.ts`; add key builders there instead of using ad hoc arrays in components.
-  instead of using ad hoc arrays in components.
+- Fetch functions should live in domain helpers under `src/lib`, such as `posts.ts`, `tags.ts`, or `wiki.ts`.
-- Fetch functions should live in domain helpers under `src/lib`, such as
+- Use `useQueryClient().invalidateQueries` with the shared root keys when mutations affect cached lists or detail views.
-  `posts.ts`, `tags.ts`, or `wiki.ts`.
+- The app-wide `QueryClient` is configured in `src/main.tsx`; do not create additional clients in feature code.
-- Use `useQueryClient().invalidateQueries` with the shared root keys when
-  mutations affect cached lists or detail views.
-- The app-wide `QueryClient` is configured in `src/main.tsx`; do not create
-  additional clients in feature code.
 
 ## API calls
 
 - Use `src/lib/api.ts` for HTTP calls.
-- The API wrapper attaches `X-Transfer-Code` from `localStorage` and converts
+- The API wrapper attaches `X-Transfer-Code` from `localStorage` and converts non-blob responses to camelCase.
-  non-blob responses to camelCase.
 - Send Rails snake_case params and request body keys where the backend expects them.
-- Do not bypass the API wrapper unless there is a specific reason, such as a
+- Do not bypass the API wrapper unless there is a specific reason, such as a third-party request outside the Rails API.
-  third-party request outside the Rails API.
 - For blob responses, pass `responseType: 'blob'` so the wrapper does not camelCase the body.
 
 ## Imports and aliases
@@ -108,41 +76,17 @@ pass or the remaining failure is clearly blocked.
 
 - Tailwind scans `src/**/*.{html,js,ts,jsx,tsx,mdx}`.
 - Use `cn` from `src/lib/utils.ts` for conditional class names and class merging.
-- Reuse components from `src/components/common`, `src/components/layout`, and
+- Reuse components from `src/components/common`, `src/components/layout`, and `src/components/ui` before adding new primitives.
-  `src/components/ui` before adding new primitives.
 - Keep Tailwind classes consistent with nearby components.
-- Prefer restrained, content-first UI chrome: avoid adding card backgrounds,
+- When adding dynamic tag color classes, update `tailwind.config.js` safelist if the class cannot be statically detected.
-  heavy borders, or nested panel decoration unless the surrounding screen
-  already uses them.
-- Keep operational screens dense and direct; trim explanatory copy and use
-  short Japanese labels that fit the control.
-- Preserve existing Japanese tone and orthography in nearby UI text, including
-  old-kana wording where the file already uses it.
-- When adding dynamic tag color classes, update `tailwind.config.js` safelist
-  if the class cannot be statically detected.
 - Do not introduce new UI libraries or production dependencies without approval.
 
-## TSX formatting
-
-- Preserve compact TSX expression shapes such as inline ternary branches and
-  closing `</div>)` forms when nearby code uses them.
-- For long Tailwind `className` strings, wrap across lines only when needed.
-- Keep continuation indentation aligned with the 4-space logical indentation
-  rule, using tabs only as leading 8-space compression.
-- Do not add braces around `if`, `else`, or `for` bodies when the body is a
-  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.
-- Avoid reformatting unrelated JSX.
-
 ## Lint and build constraints
 
-- ESLint uses `@eslint/js`, `typescript-eslint`, `eslint-plugin-react-hooks`,
+- ESLint uses `@eslint/js`, `typescript-eslint`, `eslint-plugin-react-hooks`, and `eslint-plugin-react-refresh`.
-  and `eslint-plugin-react-refresh`.
 - The hooks rules are enforced; fix hook ordering instead of disabling the rule.
 - `react-refresh/only-export-components` is enabled as a warning with `allowConstantExport`.
-- Build failures from unused locals or unused parameters are TypeScript
+- Build failures from unused locals or unused parameters are TypeScript errors, not lint-only issues.
-  errors, not lint-only issues.
 
 ## Files to avoid in routine work
 

frontend/src/App.tsx

@@ -18,7 +18,6 @@ import MaterialListPage from '@/pages/materials/MaterialListPage'
 import MaterialNewPage from '@/pages/materials/MaterialNewPage'
 // import MaterialSearchPage from '@/pages/materials/MaterialSearchPage'
 import MorePage from '@/pages/MorePage'
-import GekanatorPage from '@/pages/GekanatorPage'
 import NicoTagListPage from '@/pages/tags/NicoTagListPage'
 import NotFound from '@/pages/NotFound'
 import TOSPage from '@/pages/TOSPage.mdx'
@@ -63,9 +62,8 @@ const RouteTransitionWrapper = ({ user, setUser }: {
 	  <Route path="/tags/:id" element={<TagDetailPage/>}/>
 	  <Route path="/tags/:id/deerjikists" element={<DeerjikistDetailPage/>}/>
 	  <Route path="/tags/nico" element={<NicoTagListPage user={user}/>}/>
-	  <Route path="/nico/tags" element={<NicoTagListPage user={user}/>}/>
 	  <Route path="/tags/changes" element={<TagHistoryPage/>}/>
-	  <Route path="/theatres/:id" element={<TheatreDetailPage user={user}/>}/>
+	  <Route path="/theatres/:id" element={<TheatreDetailPage/>}/>
 	  <Route path="/materials" element={<MaterialBasePage/>}>
 	    <Route index element={<MaterialListPage/>}/>
 	    <Route path="new" element={<MaterialNewPage/>}/>
@@ -81,7 +79,6 @@ const RouteTransitionWrapper = ({ user, setUser }: {
 	  <Route path="/users/settings" element={<SettingPage user={user} setUser={setUser}/>}/>
 	  <Route path="/settings" element={<Navigate to="/users/settings" replace/>}/>
 	  <Route path="/tos" element={<TOSPage/>}/>
-	  <Route path="/gekanator" element={<GekanatorPage user={user}/>}/>
 	  <Route path="/more" element={<MorePage/>}/>
 	  <Route path="*" element={<NotFound/>}/>
 	</Routes>

frontend/src/components/NicoViewer.test.tsx

@@ -1,83 +0,0 @@
-import { act, fireEvent, render } from '@testing-library/react'
-import { afterEach, describe, expect, it, vi } from 'vitest'
-import { createRef } from 'react'
-
-import NicoViewer from '@/components/NicoViewer'
-
-import type { NiconicoViewerHandle } from '@/types'
-
-
-describe ('NicoViewer', () => {
-  afterEach (() => {
-    vi.useRealTimers ()
-  })
-
-  it ('does not time out after metadata reports a playable duration', () => {
-    vi.useFakeTimers ()
-
-    const onError = vi.fn ()
-    const onMetadataChange = vi.fn ()
-    const { container } = render (
-        <NicoViewer
-            id="sm12345"
-            width={640}
-            height={360}
-            onMetadataChange={onMetadataChange}
-            onError={onError}/>,
-    )
-    const iframe = container.querySelector ('iframe')
-    expect (iframe).not.toBeNull ()
-
-    fireEvent.load (iframe!)
-    act (() => {
-      window.dispatchEvent (new MessageEvent ('message', {
-        origin: 'https://embed.nicovideo.jp',
-        source: iframe!.contentWindow,
-        data:   {
-          eventName: 'playerMetadataChange',
-          data:      {
-            currentTime:           7,
-            duration:              120,
-            isVideoMetaDataLoaded: true,
-            maximumBuffered:       30,
-            muted:                 false,
-            showComment:           true,
-            volume:                1,
-          },
-        },
-      }))
-    })
-
-    act (() => {
-      vi.advanceTimersByTime (8_000)
-    })
-
-    expect (onMetadataChange).toHaveBeenCalled ()
-    expect (onError).not.toHaveBeenCalled ()
-  })
-
-  it ('seeks with milliseconds', () => {
-    const ref = createRef<NiconicoViewerHandle> ()
-    const { container } = render (
-        <NicoViewer
-            ref={ref}
-            id="sm12345"
-            width={640}
-            height={360}/>,
-    )
-    const iframe = container.querySelector ('iframe')!
-    const postMessage = vi.spyOn (iframe.contentWindow!, 'postMessage')
-
-    act (() => {
-      ref.current!.seek (7_000)
-    })
-
-    expect (postMessage).toHaveBeenCalledWith (
-        expect.objectContaining ({
-          eventName: 'seek',
-          data:      { time: 7_000 },
-        }),
-        'https://embed.nicovideo.jp',
-    )
-  })
-})

frontend/src/components/NicoViewer.tsx

@@ -1,11 +1,11 @@
 import { forwardRef,
-	 useCallback,
+         useCallback,
-	 useEffect,
+         useEffect,
-	 useImperativeHandle,
+         useImperativeHandle,
-	 useLayoutEffect,
+         useLayoutEffect,
-	 useMemo,
+         useMemo,
-	 useRef,
+         useRef,
-	 useState } from 'react'
+         useState } from 'react'
 
 import type { CSSProperties, ForwardedRef } from 'react'
 
@@ -14,20 +14,10 @@ import type { NiconicoMetadata, NiconicoVideoInfo, NiconicoViewerHandle } from '
 type NiconicoPlayerMessage =
     | { eventName: 'enterProgrammaticFullScreen' }
     | { eventName: 'exitProgrammaticFullScreen' }
-    | { eventName: 'loadComplete'
+    | { eventName: 'loadComplete'; playerId?: string; data: { videoInfo: NiconicoVideoInfo } }
-	playerId?:  string
+    | { eventName: 'playerMetadataChange'; playerId?: string; data: NiconicoMetadata }
-	data:       { videoInfo: NiconicoVideoInfo } }
+    | { eventName: 'playerStatusChange' | 'statusChange'; playerId?: string; data?: unknown }
-    | { eventName: 'playerMetadataChange'
+    | { eventName: 'error'; playerId?: string; data?: unknown; code?: string; message?: string }
-	playerId?:  string
-	data:       NiconicoMetadata }
-    | { eventName: 'playerStatusChange' | 'statusChange'
-	playerId?:  string
-	data?:      unknown }
-    | { eventName: 'error'
-	playerId?:  string
-	data?:      unknown
-	code?:      string
-	message?:   string }
 
 type NiconicoCommand =
     | { eventName: 'play'; sourceConnectorType: 1; playerId: string }
@@ -40,7 +30,6 @@ type NiconicoCommand =
 	data: { commentVisibility: boolean } }
 
 const EMBED_ORIGIN = 'https://embed.nicovideo.jp'
-const LOAD_COMPLETE_TIMEOUT_MS = 8_000
 
 type Props = {
     id:                 string
@@ -48,18 +37,14 @@ type Props = {
     height:             number
     style?:             CSSProperties
     onLoadComplete?:    (info: NiconicoVideoInfo) => void
-    onMetadataChange?:  (meta: NiconicoMetadata) => void
+    onMetadataChange?:  (meta: NiconicoMetadata) => void }
-    onError?:           (data: unknown) => void }
 
 
 export default forwardRef ((props: Props, ref: ForwardedRef<NiconicoViewerHandle>) => {
-  const { id, width, height, style = { }, onLoadComplete, onMetadataChange, onError } = props
+  const { id, width, height, style = { }, onLoadComplete, onMetadataChange } = props
 
   const iframeRef = useRef<HTMLIFrameElement> (null)
-  const loadCompleteTimerRef = useRef<ReturnType<typeof setTimeout> | null> (null)
+  const playerId = useMemo (() => `nico-${ id }-${ Math.random ().toString (36).slice (2) }`, [id])
-  const playerId = useMemo (
-      () => `nico-${ id }-${ Math.random ().toString (36).slice (2) }`,
-      [id])
 
   const [screenWidth, setScreenWidth] = useState<CSSProperties['width']> ()
   const [screenHeight, setScreenHeight] = useState<CSSProperties['height']> ()
@@ -79,39 +64,21 @@ export default forwardRef ((props: Props, ref: ForwardedRef<NiconicoViewerHandle
   const styleFullScreen: CSSProperties =
       fullScreen
       ? { top: 0,
-	  left: landscape ? 0 : '100%',
+          left: landscape ? 0 : '100%',
-	  position: 'fixed',
+          position: 'fixed',
-	  width: screenWidth,
+          width: screenWidth,
-	  height: screenHeight,
+          height: screenHeight,
-	  zIndex: 2_147_483_647,
+          zIndex: 2_147_483_647,
-	  maxWidth: 'none',
+          maxWidth: 'none',
-	  transformOrigin: '0% 0%',
+          transformOrigin: '0% 0%',
-	  transform: landscape ? 'none' : 'rotate(90deg)',
+          transform: landscape ? 'none' : 'rotate(90deg)',
-	  WebkitTransformOrigin: '0% 0%',
+          WebkitTransformOrigin: '0% 0%',
-	  WebkitTransform: landscape ? 'none' : 'rotate(90deg)' }
+          WebkitTransform: landscape ? 'none' : 'rotate(90deg)' }
       : { }
 
   const margedStyle: CSSProperties =
       { border: 'none', maxWidth: '100%', ...style, ...styleFullScreen }
 
-  const clearLoadCompleteTimer = useCallback (() => {
-    if (!(loadCompleteTimerRef.current))
-      return
-
-    clearTimeout (loadCompleteTimerRef.current)
-    loadCompleteTimerRef.current = null
-  }, [])
-
-  const startLoadCompleteTimer = useCallback (() => {
-    clearLoadCompleteTimer ()
-    loadCompleteTimerRef.current = setTimeout (() => {
-      onError?.({
-	  eventName: 'loadCompleteTimeout',
-	  reason:    'niconico video length was not reported by embed',
-      })
-    }, LOAD_COMPLETE_TIMEOUT_MS)
-  }, [clearLoadCompleteTimer, onError])
-
   const postToPlayer = useCallback ((message: NiconicoCommand) => {
     const win = iframeRef.current?.contentWindow
     if (!(win))
@@ -129,9 +96,7 @@ export default forwardRef ((props: Props, ref: ForwardedRef<NiconicoViewerHandle
   }, [playerId, postToPlayer])
 
   const seek = useCallback ((time: number) => {
-    postToPlayer (
+    postToPlayer ({ eventName: 'seek', sourceConnectorType: 1, playerId, data: { time } })
-	{ eventName: 'seek', sourceConnectorType: 1, playerId,
-	  data: { time } })
   }, [playerId, postToPlayer])
 
   const mute = useCallback (() => {
@@ -167,21 +132,21 @@ export default forwardRef ((props: Props, ref: ForwardedRef<NiconicoViewerHandle
   useEffect (() => {
     const onMessage = (event: MessageEvent<NiconicoPlayerMessage>) => {
       if (!(iframeRef.current)
-	  || (event.source !== iframeRef.current.contentWindow)
+          || (event.source !== iframeRef.current.contentWindow)
-	  || (event.origin !== EMBED_ORIGIN))
+          || (event.origin !== EMBED_ORIGIN))
-	return
+        return
 
       const data = event.data
 
       if (!(data)
 	  || typeof data !== 'object'
 	  || !('eventName' in data))
-	return
+        return
 
       if (('playerId' in data)
 	  && data.playerId
 	  && data.playerId !== playerId)
-	return
+        return
 
       if (data.eventName === 'enterProgrammaticFullScreen')
 	{
@@ -197,34 +162,24 @@ export default forwardRef ((props: Props, ref: ForwardedRef<NiconicoViewerHandle
 
       if (data.eventName === 'loadComplete')
 	{
-	  clearLoadCompleteTimer ()
 	  onLoadComplete?.(data.data.videoInfo)
 	  return
 	}
 
       if (data.eventName === 'playerMetadataChange')
 	{
-	  if (Number.isFinite (data.data.duration) && data.data.duration > 0)
-	    clearLoadCompleteTimer ()
-
 	  onMetadataChange?.(data.data)
 	  return
 	}
 
       if (data.eventName === 'error')
-	{
+        console.error ('niconico player error:', data)
-	  clearLoadCompleteTimer ()
-	  console.error ('niconico player error:', data)
-	  onError?.(data)
-	}
     }
 
     addEventListener ('message', onMessage)
 
     return () => removeEventListener ('message', onMessage)
-  }, [clearLoadCompleteTimer, onError, onLoadComplete, onMetadataChange, playerId])
+  }, [onLoadComplete, onMetadataChange, playerId])
-
-  useEffect (() => clearLoadCompleteTimer, [clearLoadCompleteTimer])
 
   useLayoutEffect (() => {
     if (!(fullScreen))
@@ -237,7 +192,7 @@ export default forwardRef ((props: Props, ref: ForwardedRef<NiconicoViewerHandle
 
     const pollingResize = () => {
       if (ended)
-	return
+        return
 
       const isLandscape = innerWidth >= innerHeight
       const windowWidth = `${ isLandscape ? innerWidth : innerHeight }px`
@@ -251,9 +206,9 @@ export default forwardRef ((props: Props, ref: ForwardedRef<NiconicoViewerHandle
 
     const startPollingResize = () => {
       if (requestAnimationFrame)
-	requestAnimationFrame (pollingResize)
+        requestAnimationFrame (pollingResize)
       else
-	pollingResize ()
+        pollingResize ()
     }
 
     startPollingResize ()
@@ -276,10 +231,9 @@ export default forwardRef ((props: Props, ref: ForwardedRef<NiconicoViewerHandle
       <iframe
 	  ref={iframeRef}
 	  src={src}
-		  width={width}
+	  width={width}
-		  height={height}
+	  height={height}
-		  style={margedStyle}
+	  style={margedStyle}
-		  onLoad={startLoadCompleteTimer}
+	  allowFullScreen
-		  allowFullScreen
+	  allow="autoplay"/>)
-		  allow="autoplay"/>)
 })

frontend/src/components/PostEditForm.tsx

@@ -2,36 +2,34 @@ import { useEffect, useState } from 'react'
 
 import PostFormTagsArea from '@/components/PostFormTagsArea'
 import PostOriginalCreatedTimeField from '@/components/PostOriginalCreatedTimeField'
-import FieldError from '@/components/common/FieldError'
+import Label from '@/components/common/Label'
-import FormField from '@/components/common/FormField'
 import { useDialogue } from '@/components/dialogues/DialogueProvider'
 import { Button } from '@/components/ui/button'
 import { toast } from '@/components/ui/use-toast'
 import { isApiError } from '@/lib/api'
 import { updatePost } from '@/lib/posts'
-import { inputClass } from '@/lib/utils'
+import { msToTime } from '@/lib/utils'
-import { useValidationErrors } from '@/lib/useValidationErrors'
 
 import type { FC, FormEvent } from 'react'
 
-import type { Post, Tag } from '@/types'
+import type { Post, TagWithSections } from '@/types'
-
-type PostFormField =
-    'parentPostIds' | 'tags' | 'originalCreatedAt'
 
 
-const tagsToStr = (tags: Tag[]): string => {
+const tagsToStr = (tags: TagWithSections[]): string => {
-  const result: Tag[] = []
+  const result: Omit<TagWithSections, 'children'>[] = []
 
-  const walk = (tag: Tag) => {
+  const walk = (tag: TagWithSections) => {
     const { children, ...rest } = tag
     result.push (rest)
-    children?.forEach (walk)
+    children.forEach (walk)
   }
 
   tags.filter (t => t.category !== 'nico').forEach (walk)
 
-  return [...(new Set (result.map (t => t.name)))].join (' ')
+  return [...(new Set (result.map (t =>
+      `${ t.name }${ t.sections
+		     .map (s => `[${ msToTime (s.beginMs) }-${ msToTime (s.endMs) }]`)
+		     .join ('') }`)))].join (' ')
 }
 
 
@@ -41,8 +39,6 @@ type Props = { post:    Post
 
 const PostEditForm: FC<Props> = ({ post, onSave }) => {
   const [disabled, setDisabled] = useState (false)
-  const { baseErrors, fieldErrors, clearValidationErrors, applyValidationError } =
-      useValidationErrors<PostFormField> ()
   const [originalCreatedBefore, setOriginalCreatedBefore] =
       useState<string | null> (post.originalCreatedBefore)
   const [originalCreatedFrom, setOriginalCreatedFrom] =
@@ -55,8 +51,6 @@ const PostEditForm: FC<Props> = ({ post, onSave }) => {
   const dialogue = useDialogue ()
 
   const update = async (...args: Parameters<typeof updatePost>) => {
-    clearValidationErrors ()
-
     try
     {
       const data = await updatePost (...args)
@@ -77,14 +71,7 @@ const PostEditForm: FC<Props> = ({ post, onSave }) => {
 
       if (response?.status !== 409)
 	{
-	  if (applyValidationError (e))
+	  toast ({ description: '更新はできなかったよ……' })
-	    {
-	      toast ({ description: '更新はできなかったよ……' })
-	      return
-	    }
-
-	  toast ({ title: '失敗……', description: '入力を確認してください．' })
-
 	  return
 	}
 
@@ -134,43 +121,38 @@ const PostEditForm: FC<Props> = ({ post, onSave }) => {
   }
 
   useEffect (() => {
-    setTags(tagsToStr (post.tags))
+    setTags (tagsToStr (post.tags))
   }, [post])
 
   return (
       <form onSubmit={handleSubmit} className="max-w-xl pt-2 space-y-4">
-	<FieldError messages={baseErrors}/>
-
 	{/* タイトル */}
-	<FormField label="タイトル">
+	<div>
-	  {({ invalid }) => (
+	  <Label>タイトル</Label>
-	      <input
+	  <input
-		  type="text"
+	      type="text"
-		  disabled={disabled}
+	      disabled={disabled}
-		  className={inputClass (invalid)}
+	      className="w-full border rounded p-2"
-		  value={title ?? ''}
+	      value={title ?? ''}
-		  onChange={ev => setTitle (ev.target.value)}/>)}
+	      onChange={ev => setTitle (ev.target.value)}/>
-	</FormField>
+	</div>
 
 	{/* 親投稿 */}
-	<FormField label="親投稿" messages={fieldErrors.parentPostIds}>
+	<div>
-	  {({ describedBy, invalid }) => (
+	  <Label>親投稿</Label>
-	      <input
+	  <input
-		  type="text"
+	      type="text"
-		  disabled={disabled}
+	      disabled={disabled}
-		  value={parentPostIds}
+	      value={parentPostIds}
-		  onChange={e => setParentPostIds (e.target.value)}
+	      onChange={e => setParentPostIds (e.target.value)}
-		  aria-describedby={describedBy}
+	      className="w-full border p-2 rounded"/>
-		  aria-invalid={invalid}
+	</div>
-		  className={inputClass (invalid)}/>)}
-	</FormField>
 
 	{/* タグ */}
 	<PostFormTagsArea
 	    disabled={disabled}
 	    tags={tags}
-	    setTags={setTags}
+	    setTags={setTags}/>
-	    errors={fieldErrors.tags}/>
 
 	{/* オリジナルの作成日時 */}
 	<PostOriginalCreatedTimeField
@@ -178,11 +160,12 @@ const PostEditForm: FC<Props> = ({ post, onSave }) => {
 	    originalCreatedFrom={originalCreatedFrom}
 	    setOriginalCreatedFrom={setOriginalCreatedFrom}
 	    originalCreatedBefore={originalCreatedBefore}
-	    setOriginalCreatedBefore={setOriginalCreatedBefore}
+	    setOriginalCreatedBefore={setOriginalCreatedBefore}/>
-	    errors={fieldErrors.originalCreatedAt}/>
 
 	{/* 送信 */}
-	<Button type="submit" disabled={disabled}>
+	<Button
+	    type="submit"
+	    disabled={disabled}>
 	  更新
 	</Button>
       </form>)

frontend/src/components/PostEmbed.test.tsx

@@ -8,19 +8,12 @@ const dialogue = vi.hoisted (() => ({
   confirm: vi.fn (),
 }))
 
-const nicoViewer = vi.hoisted (() => ({
-  props: vi.fn (),
-}))
-
 vi.mock ('@/components/dialogues/DialogueProvider', () => ({
   useDialogue: () => dialogue,
 }))
 
 vi.mock ('@/components/NicoViewer', () => ({
-  default: (props: { id: string }) => {
+  default: ({ id }: { id: string }) => <div>Nico:{id}</div>,
-    nicoViewer.props (props)
-    return <div>Nico:{props.id}</div>
-  },
 }))
 
 vi.mock ('react-youtube', () => ({
@@ -38,64 +31,6 @@ describe ('PostEmbed', () => {
     expect (screen.getByText ('Nico:sm12345')).toBeInTheDocument ()
   })
 
-  it ('reports niconico metadata as milliseconds', () => {
-    const onVideoReady = vi.fn ()
-    const onPlaybackChange = vi.fn ()
-    render (
-        <PostEmbed
-            post={buildPost ({ url: 'https://www.nicovideo.jp/watch/sm12345' })}
-            onVideoReady={onVideoReady}
-            onPlaybackChange={onPlaybackChange}/>,
-    )
-
-    nicoViewer.props.mock.calls[0][0].onMetadataChange ({
-      currentTime:            7_000,
-      duration:               120_000,
-      isVideoMetaDataLoaded:  true,
-      maximumBuffered:        30,
-      muted:                  false,
-      showComment:            true,
-      volume:                 1,
-    })
-
-    expect (onVideoReady).toHaveBeenCalledWith (120_000)
-    expect (onPlaybackChange).toHaveBeenCalledWith (7_000)
-  })
-
-  it ('reports niconico video readiness only once', () => {
-    const onVideoReady = vi.fn ()
-    render (
-        <PostEmbed
-            post={buildPost ({ url: 'https://www.nicovideo.jp/watch/sm12345' })}
-            onVideoReady={onVideoReady}/>,
-    )
-
-    nicoViewer.props.mock.calls[0][0].onLoadComplete ({
-      title:           '動画',
-      videoId:         'sm12345',
-      lengthInSeconds: 120,
-      thumbnailUrl:    'https://example.com/thumb.jpg',
-      description:     '',
-      viewCount:       1,
-      commentCount:    2,
-      mylistCount:     3,
-      postedAt:        '2026-01-02T03:04:05.000Z',
-      watchId:         12345,
-    })
-    nicoViewer.props.mock.calls[0][0].onMetadataChange ({
-      currentTime:            7_000,
-      duration:               120_000,
-      isVideoMetaDataLoaded:  true,
-      maximumBuffered:        30,
-      muted:                  false,
-      showComment:            true,
-      volume:                 1,
-    })
-
-    expect (onVideoReady).toHaveBeenCalledTimes (1)
-    expect (onVideoReady).toHaveBeenCalledWith (120_000)
-  })
-
   it ('embeds x/twitter status URLs', () => {
     render (<PostEmbed post={buildPost ({ url: 'https://x.com/someone/status/12345' })}/>)
 

frontend/src/components/PostEmbed.tsx

@@ -1,4 +1,4 @@
-import { useCallback, useEffect, useRef, useState } from 'react'
+import { useState } from 'react'
 import YoutubeEmbed from 'react-youtube'
 
 import NicoViewer from '@/components/NicoViewer'
@@ -8,113 +8,17 @@ import { useDialogue } from '@/components/dialogues/DialogueProvider'
 import type { FC, RefObject } from 'react'
 
 import type { NiconicoMetadata, NiconicoVideoInfo, NiconicoViewerHandle, Post } from '@/types'
-import type { YouTubePlayer } from 'react-youtube'
-
-type YouTubeEvent<T = unknown> = {
-    data:    T
-    target:  YouTubePlayer }
 
 type Props = {
     ref?:               RefObject<NiconicoViewerHandle | null>
     post:               Post
     onLoadComplete?:    (info: NiconicoVideoInfo) => void
-    onMetadataChange?:  (meta: NiconicoMetadata) => void
+    onMetadataChange?:  (meta: NiconicoMetadata) => void }
-    onVideoReady?:      (durationMs: number) => void
-    onPlaybackChange?:  (currentTimeMs: number) => number | void
-    onError?:           (data: unknown) => void }
 
 
-const PostEmbed: FC<Props> = ({
+const PostEmbed: FC<Props> = ({ ref, post, onLoadComplete, onMetadataChange }) => {
-    ref,
-    post,
-    onLoadComplete,
-    onMetadataChange,
-    onVideoReady,
-    onPlaybackChange,
-    onError,
-}) => {
   const dialogue = useDialogue ()
   const [framed, setFramed] = useState (false)
-  const [youtubePlayer, setYoutubePlayer] = useState<YouTubePlayer | null> (null)
-  const niconicoVideoReadyRef = useRef (false)
-
-  const notifyNiconicoVideoReady = useCallback ((durationMs: number) => {
-    if (niconicoVideoReadyRef.current
-	|| !(Number.isFinite (durationMs))
-	|| durationMs <= 0)
-      return
-
-    niconicoVideoReadyRef.current = true
-    onVideoReady?.(durationMs)
-  }, [onVideoReady])
-
-  const reportYoutubePlayback = useCallback (async (player: YouTubePlayer) => {
-    const currentTime = await player.getCurrentTime ()
-    const currentTimeMs = currentTime * 1_000
-    const targetTimeMs = onPlaybackChange?.(currentTimeMs)
-
-    if (typeof targetTimeMs !== 'number')
-      return
-
-    if (Math.abs (currentTimeMs - targetTimeMs) > 5_000)
-      await player.seekTo (targetTimeMs / 1_000, true)
-  }, [onPlaybackChange])
-
-  const handleYoutubeReady = async (event: YouTubeEvent) => {
-    setYoutubePlayer (event.target)
-
-    try
-    {
-      await event.target.playVideo ()
-
-      const duration = await event.target.getDuration ()
-      const durationMs = duration * 1_000
-      onVideoReady?.(durationMs)
-
-      if (!(Number.isFinite (durationMs)) || durationMs <= 0)
-	return
-
-      await reportYoutubePlayback (event.target)
-    }
-    catch (error)
-    {
-      onError?.({ platform: 'youtube', error })
-    }
-  }
-
-  const handleYoutubeStateChange = (event: YouTubeEvent<number>) => {
-    void reportYoutubePlayback (event.target)
-  }
-
-  const handleYoutubeError = (event: YouTubeEvent<number>) => {
-    onError?.({ platform: 'youtube', code: event.data })
-  }
-
-  const handleNiconicoLoadComplete = (info: NiconicoVideoInfo) => {
-    notifyNiconicoVideoReady (info.lengthInSeconds * 1_000)
-    onLoadComplete?.(info)
-  }
-
-  const handleNiconicoMetadataChange = (meta: NiconicoMetadata) => {
-    notifyNiconicoVideoReady (meta.duration)
-    onPlaybackChange?.(meta.currentTime)
-    onMetadataChange?.(meta)
-  }
-
-  useEffect (() => {
-    niconicoVideoReadyRef.current = false
-  }, [post.url])
-
-  useEffect (() => {
-    if (!(youtubePlayer) || !(onPlaybackChange))
-      return
-
-    const timer = setInterval (
-	() => void reportYoutubePlayback (youtubePlayer),
-	1_000)
-
-    return () => clearInterval (timer)
-  }, [onPlaybackChange, reportYoutubePlayback, youtubePlayer])
 
   const url = new URL (post.url)
 
@@ -134,9 +38,8 @@ const PostEmbed: FC<Props> = ({
 	      id={videoId}
 	      width={640}
 	      height={360}
-	      onLoadComplete={handleNiconicoLoadComplete}
+	      onLoadComplete={onLoadComplete}
-	      onMetadataChange={handleNiconicoMetadataChange}
+	      onMetadataChange={onMetadataChange}/>)
-	      onError={onError}/>)
     }
 
   case 'twitter.com':
@@ -166,10 +69,7 @@ const PostEmbed: FC<Props> = ({
 	      mute:         0,
 	      loop:         1,
 	      width:        '640',
-	      height:       '360' } }}
+	      height:       '360' } }}/>)
-	      onReady={handleYoutubeReady}
-	      onStateChange={handleYoutubeStateChange}
-	      onError={handleYoutubeError}/>)
     }
   }
 

frontend/src/components/PostFormTagsArea.tsx

@@ -3,7 +3,7 @@
 import { useRef, useState } from 'react'
 
 import TagSearchBox from '@/components/TagSearchBox'
-import FormField from '@/components/common/FormField'
+import Label from '@/components/common/Label'
 import TextArea from '@/components/common/TextArea'
 import { apiGet } from '@/lib/api'
 
@@ -33,11 +33,10 @@ const replaceToken = (value: string, start: number, end: number, text: string) =
 
 type Props = Omit<ComponentPropsWithoutRef<'textarea'>, 'value' | 'onChange' | 'onBlur'> & {
     tags:     string
-    setTags:  (tags: string) => void
+    setTags:  (tags: string) => void }
-    errors?:  string[] }
 
 
-const PostFormTagsArea: FC<Props> = ({ tags, setTags, errors, ...rest }) => {
+const PostFormTagsArea: FC<Props> = ({ tags, setTags, ...rest }) => {
   const ref = useRef<HTMLTextAreaElement> (null)
 
   const [bounds, setBounds] = useState<{ start: number; end: number }> ({ start: 0, end: 0 })
@@ -74,34 +73,30 @@ const PostFormTagsArea: FC<Props> = ({ tags, setTags, errors, ...rest }) => {
   }
 
   return (
-      <FormField className="relative w-full" label="タグ" messages={errors}>
+      <div className="relative w-full">
-	{({ describedBy, invalid }) => (
+	<Label>タグ</Label>
-	    <>
+	<TextArea
-	      <TextArea
+	    {...rest}
-		  {...rest}
+	    ref={ref}
-		  ref={ref}
+	    value={tags}
-		  value={tags}
+	    onChange={ev => setTags (ev.target.value)}
-		  aria-describedby={describedBy}
+	    onSelect={async (ev: SyntheticEvent<HTMLTextAreaElement>) => {
-		  invalid={invalid}
+	      const pos = (ev.target as HTMLTextAreaElement).selectionStart
-		  onChange={ev => setTags (ev.target.value)}
+	      await recompute (pos)
-		  onSelect={async (ev: SyntheticEvent<HTMLTextAreaElement>) => {
+	    }}
-		    const pos = (ev.target as HTMLTextAreaElement).selectionStart
+	    onFocus={() => setFocused (true)}
-		    await recompute (pos)
+	    onBlur={() => {
-		  }}
+	      setFocused (false)
-		  onFocus={() => setFocused (true)}
+	      setSuggestionsVsbl (false)
-		  onBlur={() => {
+	    }}/>
-		    setFocused (false)
+	{focused && (
-		    setSuggestionsVsbl (false)
+	    <TagSearchBox
-		  }}/>
+		suggestions={suggestionsVsbl && suggestions.length > 0
-	      {focused && (
+			     ? suggestions
-		  <TagSearchBox
+			     : [] as Tag[]}
-		      suggestions={suggestionsVsbl && suggestions.length > 0
+		activeIndex={-1}
-				   ? suggestions
+		onSelect={handleTagSelect}/>)}
-				   : [] as Tag[]}
+      </div>)
-		      activeIndex={-1}
-		      onSelect={handleTagSelect}/>)}
-	    </>)}
-      </FormField>)
 }
 
 export default PostFormTagsArea

frontend/src/components/PostOriginalCreatedTimeField.tsx

@@ -1,5 +1,5 @@
 import DateTimeField from '@/components/common/DateTimeField'
-import FormField from '@/components/common/FormField'
+import Label from '@/components/common/Label'
 import { Button } from '@/components/ui/button'
 
 import type { FC } from 'react'
@@ -9,81 +9,68 @@ type Props = {
     originalCreatedFrom:      string | null
     setOriginalCreatedFrom:   (x: string | null) => void
     originalCreatedBefore:    string | null
-    setOriginalCreatedBefore: (x: string | null) => void
+    setOriginalCreatedBefore: (x: string | null) => void }
-    errors?:                  string[] }
 
 
-const PostOriginalCreatedTimeField: FC<Props> = (
+const PostOriginalCreatedTimeField: FC<Props> = ({ disabled,
-    { disabled,
+		   originalCreatedFrom,
-      originalCreatedFrom,
+		   setOriginalCreatedFrom,
-      setOriginalCreatedFrom,
+		   originalCreatedBefore,
-      originalCreatedBefore,
+		   setOriginalCreatedBefore }) => (
-      setOriginalCreatedBefore,
+    <div>
-      errors }: Props,
+      <Label>オリジナルの作成日時</Label>
-) => (
+      <div className="my-1 flex">
-    <FormField label="オリジナルの作成日時" messages={errors}>
+	<div className="w-80">
-      {({ describedBy, invalid }) => (
+	  <DateTimeField
-	  <>
+	      className="mr-2"
-	    <div className="my-1 flex">
+	      disabled={disabled ?? false}
-	      <div className="w-80">
+	      value={originalCreatedFrom ?? undefined}
-		<DateTimeField
+	      onChange={setOriginalCreatedFrom}
-		    className="mr-2"
+	      onBlur={ev => {
-		    disabled={disabled ?? false}
+		const v = ev.target.value
-		    aria-describedby={describedBy}
+		if (!(v))
-		    aria-invalid={invalid}
+		  return
-		    invalid={invalid}
-		    value={originalCreatedFrom ?? undefined}
-		    onChange={setOriginalCreatedFrom}
-		    onBlur={ev => {
-		      const v = ev.target.value
-		      if (!(v))
-			return
 
-		      const d = new Date (v)
+		const d = new Date (v)
-		      if (d.getMinutes () === 0 && d.getHours () === 0)
+		if (d.getMinutes () === 0 && d.getHours () === 0)
-			d.setDate (d.getDate () + 1)
+		  d.setDate (d.getDate () + 1)
-		      else
+		else
-			d.setMinutes (d.getMinutes () + 1)
+		  d.setMinutes (d.getMinutes () + 1)
-		      setOriginalCreatedBefore (d.toISOString ())
+		setOriginalCreatedBefore (d.toISOString ())
-		    }}/>
+	      }}/>
-		以降
+	  以降
-	      </div>
+	</div>
-	      <div>
+	<div>
-		<Button
+	  <Button
-		    className="bg-gray-600 text-white rounded"
+	      className="bg-gray-600 text-white rounded"
-		    disabled={disabled}
+	      disabled={disabled}
-		    onClick={() => {
+	      onClick={() => {
-		      setOriginalCreatedFrom (null)
+		setOriginalCreatedFrom (null)
-		    }}>
+	      }}>
-		  リセット
+	    リセット
-		</Button>
+	  </Button>
-	      </div>
+	</div>
-	    </div>
+      </div>
-
+      <div className="my-1 flex">
-	    <div className="my-1 flex">
+	<div className="w-80">
-	      <div className="w-80">
+	  <DateTimeField
-		<DateTimeField
+	      className="mr-2"
-		    className="mr-2"
+	      disabled={disabled}
-		    disabled={disabled}
+	      value={originalCreatedBefore ?? undefined}
-		    aria-describedby={describedBy}
+	      onChange={setOriginalCreatedBefore}/>
-		    aria-invalid={invalid}
+	  より前
-		    invalid={invalid}
+	</div>
-		    value={originalCreatedBefore ?? undefined}
+	<div>
-		    onChange={setOriginalCreatedBefore}/>
+	  <Button
-		より前
+	      className="bg-gray-600 text-white rounded"
-	      </div>
+	      disabled={disabled}
-	      <div>
+	      onClick={() => {
-		<Button
+		setOriginalCreatedBefore (null)
-		    className="bg-gray-600 text-white rounded"
+	      }}>
-		    disabled={disabled}
+	    リセット
-		    onClick={() => {
+	  </Button>
-		      setOriginalCreatedBefore (null)
+	</div>
-		    }}>
+      </div>
-		  リセット
+    </div>)
-		</Button>
-	      </div>
-	    </div>
-	  </>)}
-    </FormField>)
 
 export default PostOriginalCreatedTimeField

frontend/src/components/TagDetailSidebar.tsx

@@ -26,13 +26,13 @@ import { dateString, originalCreatedAtString } from '@/lib/utils'
 import type { DragEndEvent } from '@dnd-kit/core'
 import type { FC, MutableRefObject, ReactNode } from 'react'
 
-import type { Category, Post, Tag } from '@/types'
+import type { Category, Post, TagWithSections } from '@/types'
 
-type TagByCategory = { [key in Category]: Tag[] }
+type TagByCategory = { [key in Category]: TagWithSections[] }
 
 
 const renderTagTree = (
-    tag:              Tag,
+    tag:              TagWithSections,
     nestLevel:        number,
     path:             string,
     suppressClickRef: MutableRefObject<boolean>,
@@ -63,7 +63,7 @@ const renderTagTree = (
 
 
 const isDescendant = (
-    root:     Tag,
+    root:     TagWithSections,
     targetId: number,
 ): boolean => {
   if (!(root.children))
@@ -84,8 +84,8 @@ const isDescendant = (
 const findTag = (
     byCat:  TagByCategory,
     id:     number,
-): Tag | undefined => {
+): TagWithSections | undefined => {
-  const walk = (nodes: Tag[]): Tag | undefined => {
+  const walk = (nodes: TagWithSections[]): TagWithSections | undefined => {
     for (const t of nodes)
       {
 	if (t.id === id)
@@ -167,7 +167,7 @@ const TagDetailSidebar: FC<Props> = ({ post, sp }) => {
       }
 
     for (const cat of Object.keys (tagsTmp) as (keyof typeof tagsTmp)[])
-      tagsTmp[cat].sort ((tagA: Tag, tagB: Tag) => tagA.name < tagB.name ? -1 : 1)
+      tagsTmp[cat].sort ((tagA: TagWithSections, tagB: TagWithSections) => tagA.name < tagB.name ? -1 : 1)
 
     return tagsTmp
   }, [post])

frontend/src/components/TagSearch.tsx

@@ -4,7 +4,6 @@ import { useEffect, useState } from 'react'
 import { useNavigate, useLocation } from 'react-router-dom'
 
 import { apiGet } from '@/lib/api'
-import { inputClass } from '@/lib/utils'
 
 import TagSearchBox from './TagSearchBox'
 
@@ -111,8 +110,7 @@ const TagSearch: FC = () => {
 	       onFocus={() => setSuggestionsVsbl (true)}
 	       onBlur={() => setSuggestionsVsbl (false)}
 	       onKeyDown={handleKeyDown}
-	       className={inputClass (false,
+	       className="w-full px-3 py-2 border rounded dark:border-gray-600 dark:bg-gray-800 dark:text-white"/>
-				      'px-3 py-2 dark:border-gray-600 dark:bg-gray-800 dark:text-white')}/>
 	<TagSearchBox suggestions={suggestionsVsbl && suggestions.length ? suggestions : [] as Tag[]}
 		      activeIndex={activeIndex}
 		      onSelect={handleTagSelect}/>

frontend/src/components/TopNav.tsx

@@ -55,6 +55,12 @@ export const menuOutline = ({ tag, wikiId, user, pathName }: {
 	  { name: '追加', to: '/materials/new' },
 	  { name: '全体履歴', to: '/materials/changes', visible: false },
 	  { name: 'ヘルプ', to: '/wiki/ヘルプ:素材集' }] },
+      { name: '上映会', to: '/theatres/1', base: '/theatres', subMenu: [
+	  { name: <>第&thinsp;1&thinsp;会場</>, to: '/theatres/1' },
+	  { name: 'CyTube', to: '//cytube.mm428.net/r/deernijika' },
+	  { name: <>ニジカ放送局第&thinsp;1&thinsp;チャンネル</>,
+	    to: '//www.youtube.com/watch?v=DCU3hL4Uu6A' },
+	  { name: 'ヘルプ', to: '/wiki/ヘルプ:上映会' }] },
       { name: 'Wiki', to: '/wiki/ヘルプ:ホーム', base: '/wiki', subMenu: [
 	  { name: '検索', to: '/wiki' },
 	  { name: '新規', to: '/wiki/new' },
@@ -65,9 +71,6 @@ export const menuOutline = ({ tag, wikiId, user, pathName }: {
 	    visible: wikiPageFlg },
 	  { name: '履歴', to: `/wiki/changes?id=${ wikiId }`, visible: wikiPageFlg },
 	  { name: '編輯', to: `/wiki/${ wikiId || wikiTitle }/edit`, visible: wikiPageFlg }] },
-      { name: 'おたのしみ', visible: false, subMenu: [
-	  { name: '上映会 (β)', to: '/theatres/1' },
-	  { name: 'グカネータ (β)', to: '/gekanator' }] },
       { name: 'ユーザ', to: '/users/settings', visible: false, subMenu: [
 	  { name: '一覧', to: '/users', visible: false },
 	  { name: 'お前', to: `/users/${ user?.id }`, visible: false },
@@ -129,12 +132,8 @@ const TopNav: FC<Props> = ({ user }) => {
 
   const menu = menuOutline ({ tag, wikiId, user, pathName: location.pathname })
   const visibleMenu = menu.filter ((item): item is MenuVisibleItem => item.visible ?? true)
-  const moreMenu = menu.filter (item =>
-      !(item.visible ?? true)
-      || item.subMenu.filter (subItem => subItem.visible ?? true).length > 0)
   const activeIdx =
       visibleMenu.findIndex (item => location.pathname.startsWith (item.base || item.to))
-  const submenuHeight = moreVsbl ? 40 * moreMenu.length : (activeIdx < 0 ? 0 : 40)
 
   const prevActiveIdxRef = useRef<number> (activeIdx)
 
@@ -245,9 +244,9 @@ const TopNav: FC<Props> = ({ user }) => {
 	  <motion.div
 	      key="submenu-shell"
 	      layout
-	      className="relative z-20 hidden md:block overflow-hidden
+	      className="relative hidden md:block overflow-hidden
 			 bg-yellow-200 dark:bg-red-950"
-	      animate={{ height: submenuHeight }}
+	      style={{ height: moreVsbl ? 40 * menu.length : (activeIdx < 0 ? 0 : 40) }}
 	      onMouseLeave={() => {
 		if (moreVsbl)
 		  setMoreVsbl (false)
@@ -258,7 +257,7 @@ const TopNav: FC<Props> = ({ user }) => {
 	      }}>
 	  {moreVsbl
 	   ? (
-	      moreMenu.map ((item, i) => (
+	      menu.map ((item, i) => (
 		  <div key={i} className="relative h-[40px]">
 		    <div className="absolute inset-0 flex items-center px-3">
 		      <motion.div
@@ -268,7 +267,7 @@ const TopNav: FC<Props> = ({ user }) => {
 			       : { initial: { x: 40, y: -40, opacity: 0 },
 				   animate: { x: 0, y: 0, opacity: 1 },
 				   exit: { x: 40, y: -40, opacity: 0 } })}
-			  className="z-10 h-full flex items-center px-3 font-bold w-28">
+			  className="z-10 h-full flex items-center px-3 font-bold w-24">
 			<h2>{item.name}</h2>
 		      </motion.div>
 		      {item.subMenu