#63

.gitea/ISSUE_TEMPLATE.md

@@ -1,35 +0,0 @@
-## 背景
-
-なぜ必要か。
-
-## 対象範囲
-
-- backend:
-- frontend:
-- docs:
-- migration:
-
-## やること
-
-- [ ] 
-
-## 受け入れ条件
-
-- [ ] 
-
-## 実行すべき確認
-
-- [ ] `cd backend && bundle exec rspec`
-- [ ] `cd frontend && npm run build`
-- [ ] `cd frontend && npm run lint`
-
-## 禁止事項
-
-- unrelated refactor はしない
-- 既存 API response shape を壊さない
-- 認証・認可・BAN を弱めない
-
-## Codex への指示
-
-この issue を読んで実装してください。
-不明点があれば、実装前に調査結果と選択肢を提示してください。

AGENTS.md

@@ -1,234 +0,0 @@
-# AGENTS.md
-
-## Project overview
-
-BTRC Hub / タグ広場 is a split Rails API and React frontend repository.
-
-- Backend: Rails API under `backend/`.
-- Frontend: React + TypeScript + Vite under `frontend/`.
-- Docs: lightweight command notes under `docs/`.
-- There is no README or Makefile at the repository root as of this inspection.
-
-## Stack
-
-- Backend: Ruby `3.2.2` from `backend/.ruby-version`, Rails `~> 8.0.2`.
-- Backend dependencies include `mysql2`, `sqlite3`, `rspec-rails`,
-  `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,
-  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,
-  wiki commit, YouTube sync, and similarity calculation.
-- `backend/config/routes.rb`: API routes.
-- `backend/db/migrate`: migrations.
-- `backend/db/schema.rb`: current schema snapshot.
-- `backend/lib/tasks`: custom Rake tasks.
-- `backend/spec`: RSpec tests.
-- `backend/test`: Rails minitest files that still exist in the tree.
-- `frontend/src/App.tsx`: frontend route definitions and initial user setup.
-- `frontend/src/pages`: page-level React components.
-- `frontend/src/components`: shared and feature components.
-- `frontend/src/lib`: API client helpers, query keys, prefetchers, and domain helpers.
-- `frontend/src/stores`: Zustand stores.
-- `docs/commands.md`: command notes.
-
-## Commands
-
-Only list commands that are backed by files inspected in this repository.
-
-### Backend
-
-The following binstubs exist under `backend/bin`:
-
-```sh
-cd backend
-bin/setup
-bin/dev
-bin/rails
-bin/rake
-bin/rubocop
-bin/brakeman
-bin/kamal
-bin/thrust
-```
-
-Common Rails/Rake usage through existing binstubs:
-
-```sh
-cd backend
-bin/rails db:prepare
-bin/rails db:migrate
-bin/rails routes
-bin/rails server
-bin/rake
-bin/rubocop
-bin/brakeman
-```
-
-RSpec is present in `Gemfile` and `.rspec` exists:
-
-```sh
-cd backend
-bundle exec rspec
-```
-
-### Frontend
-
-The following npm scripts exist in `frontend/package.json`:
-
-```sh
-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
-`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.
-
-## 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
-  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.
-- 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
-  editing backend behavior.
-- For API behavior changes, add or update request specs under
-  `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
-  explicitly changes authentication.
-- 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`;
-  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
-  under `frontend/src/components` unless existing patterns point elsewhere.
-- Match existing Tailwind, component, and import alias conventions.
-
-### 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.
-
-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
-  `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.
-- 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
-
-A task is complete only when:
-
-- implementation is complete,
-- relevant non-test verification commands pass, or failures are clearly
-  explained,
-- unrelated files are not changed,
-- migrations and schema are consistent when schema changes are made,
-- user-facing behavior is documented when needed.

backend/AGENTS.md

@@ -1,219 +0,0 @@
-# backend/AGENTS.md
-
-## Scope
-
-These rules apply to work under `backend/`.
-
-This is a Rails API app using Active Record, RSpec, request specs,
-service objects, representation classes, and version tables for post/tag/wiki
-history.
-
-## Commands
-
-Use commands backed by files and dependencies in this directory:
-
-```sh
-bin/setup
-bin/dev
-bin/rails
-bin/rake
-bin/rubocop
-bin/brakeman
-bundle exec rspec
-```
-
-Common checks:
-
-```sh
-bundle exec rspec
-bin/rubocop
-bin/brakeman
-```
-
-Common Rails commands:
-
-```sh
-bin/rails db:prepare
-bin/rails db:migrate
-bin/rails routes
-bin/rails server
-```
-
-After backend behavior changes, run the relevant RSpec files. For broad backend changes, run:
-
-```sh
-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,
-  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,
-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
-  `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
-  explicitly changes authentication.
-- 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
-  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.
-
-## BAN and IP BAN
-
-- `ApplicationController` runs these before actions in order:
-  - `reject_banned_ip_address!`
-  - `authenticate_user`
-  - `reject_banned_user!`
-- 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
-  update request specs covering banned users and banned IP addresses only when
-  the user explicitly asks for tests.
-
-## RSpec
-
-- Prefer RSpec for new backend tests.
-- Put API behavior coverage under `spec/requests`.
-- Put model behavior under `spec/models`.
-- Put service behavior under `spec/services`.
-- 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
-  `ApplicationController#current_user`; use it when matching existing
-  request spec style.
-- Add or update request specs for API behavior changes only when the user
-  explicitly asks for tests, especially status codes, permissions, response
-  shape, and version conflict behavior.
-
-## 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
-  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
-  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
-  `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
-  rows in application code:
-  - `PostVersionRecorder`
-  - `TagVersionRecorder`
-  - `NicoTagVersionRecorder`
-  - `WikiVersionRecorder`
-  - `TagVersioning`
-- `VersionRecorder` locks the current record, validates sequence consistency,
-  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
-  `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,
-  viewed state, and version conflict behavior.
-- Tags have canonical names, aliases through `TagName`, categories, parent
-  implications, discard behavior, and version snapshots.
-- Nico tags have separate relation/version behavior; do not treat them like
-  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.
-- Frontend code expects camelCase conversion client-side, while Rails params
-  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
-  directories unless explicitly needed.
-- 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

@@ -1,19 +1,14 @@
 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!
 
-  def current_user = @current_user
+  def current_user
+    @current_user
+  end
 
   private
 
   def authenticate_user
     code = request.headers['X-Transfer-Code'] || request.headers['HTTP_X_TRANSFER_CODE']
-    return if code.blank?
-
     @current_user = User.find_by(inheritance_code: code)
   end
 
@@ -27,62 +22,4 @@ class ApplicationController < ActionController::API
       s.in?(['', '1', 'true', 'on', 'yes'])
     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?
-
-    head :forbidden
-  end
-
-  def reject_banned_user!
-    return unless current_user&.banned?
-
-    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

@@ -1,140 +0,0 @@
-class GekanatorGamesController < ApplicationController
-  def create
-    return head :not_found unless current_user&.admin?
-
-    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
-    return head :not_found unless current_user&.admin?
-
-    game = GekanatorGame.find_by(id: params[:id])
-    return head :not_found unless game
-
-    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
-    return head :not_found unless current_user&.admin?
-
-    game = GekanatorGame.find_by(id: params[:id])
-    return head :not_found unless game
-
-    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
-end

backend/app/controllers/gekanator_posts_controller.rb

@@ -1,46 +0,0 @@
-class GekanatorPostsController < ApplicationController
-  def index
-    return head :not_found unless current_user&.admin?
-
-    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

@@ -1,53 +0,0 @@
-class GekanatorQuestionSuggestionsController < ApplicationController
-  def create
-    return head :not_found unless current_user&.admin?
-
-    game = GekanatorGame.find_by(id: params.require(:gekanator_game_id))
-    return head :not_found unless game
-
-    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

@@ -1,100 +0,0 @@
-class GekanatorQuestionsController < ApplicationController
-  def index
-    return head :not_found unless current_user&.admin?
-
-    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 '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?"
-    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'
-        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
-
-    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? }
+    return head :bad_request if linked_tags.any? { |t| t.nico? }
-        raise Tag::NicoTagNormalisationError
-      end
 
+    ApplicationRecord.transaction do
       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: [:materials, { tag_name: :wiki_page }])
-                 tags: [:deerjikists, :materials, { tag_name: :wiki_page }])
         .with_attached_thumbnail
 
     q = q.where('posts.url LIKE ?', "%#{ url }%") if url
@@ -96,9 +95,7 @@ class PostsController < ApplicationController
   end
 
   def random
-    post = filtered_posts.preload(:uploaded_user, :parents, :children,
+    post = filtered_posts.preload(tags: [:materials, { tag_name: :wiki_page }])
-                                  tags: [:deerjikists, :materials, { tag_name: :wiki_page }])
-                         .with_attached_thumbnail
                          .order('RAND()')
                          .first
     return head :not_found unless post
@@ -107,25 +104,12 @@ class PostsController < ApplicationController
   end
 
   def show
-    post =
+    post = Post.includes(tags: [: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.tags),
-    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
@@ -164,11 +148,11 @@ 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
@@ -189,76 +173,41 @@ class PostsController < ApplicationController
     return head :unauthorized unless current_user
     return head :forbidden unless current_user.gte_member?
 
-    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
-
-    base_version_no = parse_base_version_no
-    return render_bad_request('base_version_no は必須です．') if !(force) && !(base_version_no)
-
     title = params[:title].presence
     tag_names = params[:tags].to_s.split
     original_created_from = params[:original_created_from]
     original_created_before = params[:original_created_before]
     parent_post_ids = parse_parent_post_ids
 
-    post = nil
+    post = Post.find(params[:id].to_i)
-    conflict_json = nil
 
     ApplicationRecord.transaction do
-      post = Post.lock.find(params[:id].to_i)
+      PostVersionRecorder.ensure_snapshot!(post, created_by_user: current_user)
 
-      base_version = nil
+      post.update!(title:, original_created_from:, original_created_before:)
-      base_snapshot = nil
-      current_snapshot = nil
-      unless force
-        base_version = post.post_versions.find_by!(version_no: base_version_no)
 
-        base_snapshot = post_snapshot_from_version(base_version)
+      normalised_tags = Tag.normalise_tags!(tag_names, with_tagme: false)
-        current_snapshot = post_snapshot_from_record(post)
+      TagVersioning.record_tag_snapshots!(normalised_tags, created_by_user: current_user)
+
+      tags = post.tags.nico.to_a + normalised_tags
+      tags = Tag.expand_parent_tags(tags)
+      sync_post_tags!(post, tags)
+
+      sync_parent_posts!(post, parent_post_ids)
+
+      PostVersionRecorder.record!(post:, event_type: :update, created_by_user: current_user)
     end
-      incoming_snapshot = post_incoming_snapshot(title:,
-                                                 original_created_from:,
-                                                 original_created_before:,
-                                                 tag_names:,
-                                                 parent_post_ids:)
-
-      snapshot_to_apply =
-          if force || post.version_no == base_version_no || current_snapshot == base_snapshot
-            incoming_snapshot
-          else
-            changes = post_snapshot_changes(base_snapshot, current_snapshot, incoming_snapshot)
-            conflicts = changes.select { |change| change[:conflict] }
-
-            if merge && conflicts.empty?
-              merge_post_snapshots(base_snapshot, current_snapshot, incoming_snapshot)
-            else
-              conflict_json = post_conflict_json(post:,
-                                                 base_version_no:,
-                                                 base_snapshot:,
-                                                 current_snapshot:,
-                                                 incoming_snapshot:,
-                                                 changes:,
-                                                 conflicts:)
-              raise ActiveRecord::Rollback
-            end
-          end
-
-      apply_post_snapshot!(post, snapshot_to_apply)
-    end
-
-    return render json: conflict_json, status: :conflict if conflict_json
 
     post.reload
-    json = PostRepr.base(post, current_user)
+    json = post.as_json
     json['tags'] = build_tag_tree_for(post.tags)
     render json:, status: :ok
   rescue Tag::NicoTagNormalisationError
-    render_validation_error fields: { tags: ['ニコニコ・タグは直接指定できません．'] }
+    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
@@ -276,7 +225,7 @@ class PostsController < ApplicationController
     pts = pts.where(post_id: id) if id.present?
     pts = pts.where(tag_id:) if tag_id.present?
     pts = pts.includes(:post, :created_user, :deleted_user,
-                       tag: [:deerjikists, :materials, { tag_name: :wiki_page }])
+                       tag: [:materials, { tag_name: :wiki_page }])
 
     events = []
     pts.each do |pt|
@@ -401,7 +350,7 @@ class PostsController < ApplicationController
       return nil unless tag
 
       if path.include?(tag_id)
-        return TagRepr.inline(tag).merge(children: [])
+        return TagRepr.base(tag).merge(children: [])
       end
 
       if memo.key?(tag_id)
@@ -413,26 +362,12 @@ 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:)
     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)
 
@@ -446,7 +381,7 @@ 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 +389,7 @@ 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
 
@@ -470,215 +404,4 @@ class PostsController < ApplicationController
       PostImplication.create_or_find_by!(post_id: post.id, parent_post_id:)
     end
   end
-
-  def parse_base_version_no
-    version_no = Integer(params[:base_version_no], exception: false)
-    if version_no&.positive?
-      version_no
-    else
-      nil
-    end
-  end
-
-  def post_snapshot_from_version version
-    { title: version.title,
-      original_created_from: snapshot_time(version.original_created_from),
-      original_created_before: snapshot_time(version.original_created_before),
-      tag_names: editable_tag_names_from_version(version),
-      parent_post_ids: snapshot_parent_post_ids_from_version(version) }
-  end
-
-  def editable_tag_names_from_version version
-    version.tags.to_s.split.reject { |name| name.downcase.start_with?('nico:') }.sort
-  end
-
-  def post_snapshot_from_record post
-    { title: post.title,
-      original_created_from: snapshot_time(post.original_created_from),
-      original_created_before: snapshot_time(post.original_created_before),
-      tag_names: editable_tag_names_from_post(post),
-      parent_post_ids: post.parent_posts.order(:id).pluck(:id) }
-  end
-
-  def editable_tag_names_from_post post
-    post.tags.not_nico.joins(:tag_name).order('tag_names.name').pluck('tag_names.name')
-  end
-
-  def post_incoming_snapshot title:, original_created_from:, original_created_before:,
-                             tag_names:, parent_post_ids:
-    { title:,
-      original_created_from: snapshot_time(original_created_from),
-      original_created_before: snapshot_time(original_created_before),
-      tag_names: incoming_tag_names_for_snapshot(tag_names),
-      parent_post_ids: parent_post_ids.sort }
-  end
-
-  def snapshot_parent_post_ids_from_version version
-    if version.respond_to?(:parent_post_ids)
-      version.parent_post_ids.to_s.split.map { |id| id.to_i }.sort
-    elsif version.respond_to?(:parent_id) && version.parent_id
-      [version.parent_id]
-    else
-      []
-    end
-  end
-
-  def snapshot_time value
-    return nil if value.blank?
-
-    value = Time.zone.parse(value.to_s) if value in String
-    value&.in_time_zone&.iso8601(6)
-  rescue ArgumentError, TypeError
-    value.to_s
-  end
-
-  def incoming_tag_names_for_snapshot raw_tag_names
-    tags = Tag.normalise_tags!(raw_tag_names, with_tagme: false)
-
-    Tag.expand_parent_tags(tags).map(&:name).uniq.sort
-  end
-
-  def post_conflict_json post:, base_version_no:, base_snapshot:,
-                         current_snapshot:, incoming_snapshot:, changes:, conflicts:
-    { error: 'conflict',
-      message: '競合が発生しました．',
-      post_id: post.id,
-      base_version_no:,
-      current_version_no: post.version_no,
-      base: base_snapshot,
-      current: current_snapshot,
-      mine: incoming_snapshot,
-      changes:,
-      conflicts:,
-      mergeable: conflicts.empty? }
-  end
-
-  def post_snapshot_changes base_snapshot, current_snapshot, incoming_snapshot
-    [scalar_snapshot_change(:title, 'タイトル',
-                            base_snapshot, current_snapshot, incoming_snapshot),
-     scalar_snapshot_change(:original_created_from, 'オリジナルの作成日時（以降）',
-                            base_snapshot, current_snapshot, incoming_snapshot),
-     scalar_snapshot_change(:original_created_before, 'オリジナルの作成日時（より前）',
-                            base_snapshot, current_snapshot, incoming_snapshot),
-     set_snapshot_change(:tag_names, 'タグ',
-                         base_snapshot, current_snapshot, incoming_snapshot),
-     set_snapshot_change(:parent_post_ids, '親投稿',
-                         base_snapshot, current_snapshot, incoming_snapshot)].compact
-  end
-
-  def scalar_snapshot_change field, label, base_snapshot, current_snapshot, incoming_snapshot
-    base = base_snapshot[field]
-    current = current_snapshot[field]
-    mine = incoming_snapshot[field]
-
-    return nil if current == base && mine == base
-
-    { field:, label:, base:, current:, mine:,
-      changed_by_current: current != base,
-      changed_by_me: mine != base,
-      conflict: scalar_snapshot_conflict?(base, current, mine) }
-  end
-
-  def scalar_snapshot_conflict? base, current, mine
-    current != base && mine != base && current != mine
-  end
-
-  def set_snapshot_change field, label, base_snapshot, current_snapshot, incoming_snapshot
-    base = base_snapshot[field].to_a
-    current = current_snapshot[field].to_a
-    mine = incoming_snapshot[field].to_a
-
-    added_by_current = current - base
-    removed_by_current = base - current
-    added_by_me = mine - base
-    removed_by_me = base - mine
-
-    if (added_by_current.empty? &&
-        removed_by_current.empty? &&
-        added_by_me.empty? &&
-        removed_by_me.empty?)
-      return nil
-    end
-
-    { field:, label:, base:, current:, mine:, added_by_current:, removed_by_current:,
-      added_by_me:, removed_by_me:,
-      changed_by_current: added_by_current.present? || removed_by_current.present?,
-      changed_by_me: added_by_me.present? || removed_by_me.present?,
-      conflict: set_snapshot_conflict?(added_by_current:,
-                                       removed_by_current:,
-                                       added_by_me:,
-                                       removed_by_me:) }
-  end
-
-  def set_snapshot_conflict? added_by_current:, removed_by_current:,
-                             added_by_me:, removed_by_me:
-    (added_by_current & removed_by_me).present? || (removed_by_current & added_by_me).present?
-  end
-
-  def apply_post_snapshot! post, snapshot
-    PostVersionRecorder.ensure_snapshot!(post, created_by_user: current_user)
-
-    post.update!(title: snapshot[:title],
-                 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)
-    TagVersioning.record_tag_snapshots!(editable_tags, created_by_user: current_user)
-
-    readonly_tags = post.tags.nico.to_a
-
-    tags = readonly_tags + editable_tags
-    tags = Tag.expand_parent_tags(tags)
-
-    sync_post_tags!(post, tags)
-    sync_parent_posts!(post, snapshot[:parent_post_ids])
-
-    PostVersionRecorder.record!(post:, event_type: :update, created_by_user: current_user)
-  end
-
-  def merge_post_snapshots base_snapshot, current_snapshot, incoming_snapshot
-    [:title, :original_created_from, :original_created_before].map {
-      [_1, merge_scalar_snapshot_value(base_snapshot[_1],
-                                       current_snapshot[_1],
-                                       incoming_snapshot[_1])]
-    }.to_h.merge([:tag_names, :parent_post_ids].map {
-      [_1, merge_set_snapshot_value(base_snapshot[_1],
-                                    current_snapshot[_1],
-                                    incoming_snapshot[_1])]
-    }.to_h)
-  end
-
-  def merge_scalar_snapshot_value base, current, mine
-    return mine if current == base
-    return current if mine == base || current == mine
-
-    raise ArgumentError, '競合してゐる項目はマージできません．'
-  end
-
-  def merge_set_snapshot_value base, current, mine
-    base = base.to_a
-    current = current.to_a
-    mine = mine.to_a
-
-    added_by_current = current - base
-    removed_by_current = base - current
-    added_by_me = mine - base
-    removed_by_me = base - mine
-
-    merged = base + added_by_current + added_by_me
-    merged -= removed_by_current
-    merged -= removed_by_me
-
-    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

@@ -1,6 +1,9 @@
 class UsersController < ApplicationController
   def create
+    return head :unprocessable_entity if request.remote_ip.blank?
+
     user = nil
+
     User.transaction do
       user = User.create!(inheritance_code: SecureRandom.uuid, role: :guest)
       attach_ip_address!(user)
@@ -14,7 +17,8 @@ class UsersController < ApplicationController
   def verify
     user = User.find_by(inheritance_code: params[:code])
     return render json: { valid: false } unless user
-    return head :forbidden if user.banned?
+
+    return head :unprocessable_entity if request.remote_ip.blank?
 
     attach_ip_address!(user)
 
@@ -42,12 +46,12 @@ 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/ip_address.rb

@@ -1,10 +1,7 @@
 class IpAddress < ApplicationRecord
   validates :ip_address, presence: true, length: { maximum: 16 }
+  validates :banned, inclusion: { in: [true, false] }
 
   has_many :user_ips, dependent: :destroy
   has_many :users, through: :user_ips
-
-  def banned? = banned_at.present?
-  def ban! = banned? || update!(banned_at: Time.current)
-  def unban! = update!(banned_at: nil)
 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',
@@ -39,8 +28,6 @@ class Post < ApplicationRecord
 
   has_one_attached :thumbnail
 
-  attribute :version_no, :integer, default: 1
-
   before_validation :normalise_url
 
   validates :url, presence: true, uniqueness: true
@@ -105,7 +92,7 @@ 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/tag.rb

@@ -40,8 +40,6 @@ class Tag < ApplicationRecord
   belongs_to :tag_name
   delegate :wiki_page, to: :tag_name
 
-  attribute :version_no, :integer, default: 1
-
   delegate :name, to: :tag_name, allow_nil: true
   validates :tag_name, presence: true
 
@@ -81,7 +79,7 @@ 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)

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/models/user.rb

@@ -4,6 +4,7 @@ class User < ApplicationRecord
   validates :name, length: { maximum: 255 }
   validates :inheritance_code, presence: true, length: { maximum: 64 }
   validates :role, presence: true, inclusion: { in: roles.keys }
+  validates :banned, inclusion: { in: [true, false] }
 
   has_many :created_posts,
            class_name: 'Post', foreign_key: :uploaded_user_id, dependent: :nullify
@@ -18,10 +19,5 @@ class User < ApplicationRecord
            class_name: 'WikiPage', foreign_key: :updated_user_id, dependent: :nullify
 
   def viewed?(post) = user_post_views.exists?(post_id: post.id)
-
   def gte_member? = member? || admin?
-
-  def banned? = banned_at.present?
-  def ban! = banned? || update!(banned_at: Time.current)
-  def unban! = update!(banned_at: nil)
 end

backend/app/models/wiki_page.rb

@@ -15,8 +15,6 @@ class WikiPage < ApplicationRecord
 
   has_many :wiki_versions
 
-  attribute :version_no, :integer, default: 1
-
   belongs_to :tag_name
   validates :tag_name, presence: true
   validates :body, presence: true

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

@@ -1,18 +0,0 @@
-module Gekanator
-  class QuestionSuggestionAiConverter
-    def self.call(...) = new(...).call
-
-    def initialize suggestion:, user:
-      @suggestion = suggestion
-      @user = user
-    end
-
-    def call
-      raise NotImplementedError, 'AI question conversion is not implemented yet.'
-    end
-
-    private
-
-    attr_reader :suggestion, :user
-  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/app/services/version_recorder.rb

@@ -16,20 +16,19 @@ class VersionRecorder
       @record = record_class.unscoped.lock.find(@record.id)
       latest = latest_version
 
-      validate_version_sequence!(latest)
+      if !(latest) && @event_type != 'create'
+        raise "#{ version_class.name } first event must be create"
+      end
+
+      if @event_type == 'create' && latest
+        raise "#{ version_class.name } create event already exists"
+      end
 
       attrs = snapshot_attributes
 
-      if @event_type == 'update' && latest && same_snapshot?(latest, attrs)
+      return latest if @event_type == 'update' && latest && same_snapshot?(latest, attrs)
-        return latest
-      end
 
-      version = version_class.create!(
+      version_class.create!(base_attributes(latest).merge(record_key => @record).merge(attrs))
-          base_attributes(latest).merge(record_key => @record).merge(attrs))
-
-      update_record_version_no!(version.version_no)
-
-      version
     end
   end
 
@@ -46,31 +45,7 @@ class VersionRecorder
       created_by_user: @created_by_user }
   end
 
-  def update_record_version_no! version_no
+  def same_snapshot?(version, attrs) = attrs.all? { |k, v| version.public_send(k) == v }
-    @record.update_columns(version_no:)
-    @record.version_no = version_no
-  end
-
-  def validate_version_sequence! latest
-    if !(latest) && @event_type != 'create'
-      raise "#{ version_class.name } first event must be create"
-    end
-
-    if @event_type == 'create' && latest
-      raise "#{ version_class.name } create event already exists"
-    end
-
-    return unless latest
-
-    if @record.version_no != latest.version_no
-      raise ("#{ record_class.name }##{ @record.id } version_no is #{ @record.version_no }, " +
-             "but latest #{ version_class.name } version_no is #{ latest.version_no }")
-    end
-  end
-
-  def same_snapshot? version, attrs
-    attrs.all? { |k, v| version.public_send(k) == v }
-  end
 
   def validate_event_type!
     return if EVENT_TYPES.include?(@event_type)

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/20260501153900_rename_banned_to_banned_at_in_users_and_ip_addresses.rb

@@ -1,16 +0,0 @@
-class RenameBannedToBannedAtInUsersAndIpAddresses < ActiveRecord::Migration[8.0]
-  def up
-    [:users, :ip_addresses].each do
-      add_column _1, :banned_at, :datetime, after: :banned
-      add_index _1, :banned_at
-      remove_column _1, :banned
-    end
-  end
-
-  def down
-    [:ip_addresses, :users].each do
-      add_column _1, :banned, :boolean, null: false, default: false, after: :banned_at
-      remove_column _1, :banned_at
-    end
-  end
-end

backend/db/migrate/20260507124000_add_version_no_to_posts.rb

@@ -1,27 +0,0 @@
-class AddVersionNoToPosts < ActiveRecord::Migration[8.0]
-  def up
-    add_column :posts, :version_no, :integer
-
-    execute <<~SQL
-      UPDATE
-        posts
-      SET
-        version_no = (
-          SELECT
-            MAX(version_no)
-          FROM
-            post_versions
-          WHERE
-            post_id = posts.id)
-    SQL
-
-    change_column_null :posts, :version_no, false
-
-    add_check_constraint :posts, 'version_no > 0', name: 'chk_posts_version_no_positive'
-  end
-
-  def down
-    remove_check_constraint :posts, name: 'chk_posts_version_no_positive'
-    remove_column :posts, :version_no
-  end
-end

backend/db/migrate/20260507211600_add_version_no_to_tags.rb

@@ -1,37 +0,0 @@
-class AddVersionNoToTags < ActiveRecord::Migration[8.0]
-  def up
-    add_column :tags, :version_no, :integer
-
-    execute <<~SQL
-      UPDATE
-        tags
-      SET
-        version_no = (
-          CASE category
-          WHEN 'nico' THEN
-            (SELECT
-               MAX(version_no)
-             FROM
-               nico_tag_versions
-             WHERE
-               tag_id = tags.id)
-          ELSE
-            (SELECT
-               MAX(version_no)
-             FROM
-               tag_versions
-             WHERE
-               tag_id = tags.id)
-          END)
-    SQL
-
-    change_column_null :tags, :version_no, false
-
-    add_check_constraint :tags, 'version_no > 0', name: 'chk_tags_version_no_positive'
-  end
-
-  def down
-    remove_check_constraint :tags, name: 'chk_tags_version_no_positive'
-    remove_column :tags, :version_no
-  end
-end

backend/db/migrate/20260507213300_add_version_no_to_wiki_pages.rb

@@ -1,27 +0,0 @@
-class AddVersionNoToWikiPages < ActiveRecord::Migration[8.0]
-  def up
-    add_column :wiki_pages, :version_no, :integer
-
-    execute <<~SQL
-      UPDATE
-        wiki_pages
-      SET
-        version_no = (
-          SELECT
-            MAX(version_no)
-          FROM
-            wiki_versions
-          WHERE
-            wiki_page_id = wiki_pages.id)
-    SQL
-
-    change_column_null :wiki_pages, :version_no, false
-
-    add_check_constraint :wiki_pages, 'version_no > 0', name: 'chk_wiki_pages_version_no_positive'
-  end
-
-  def down
-    remove_check_constraint :wiki_pages, name: 'chk_wiki_pages_version_no_positive'
-    remove_column :wiki_pages, :version_no
-  end
-end

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/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_04_27_214800) 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
@@ -48,85 +48,11 @@ 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"
+    t.boolean "banned", default: false, null: false
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
-    t.index ["banned_at"], name: "index_ip_addresses_on_banned_at"
     t.index ["ip_address"], name: "index_ip_addresses_on_ip_address", unique: true
   end
 
@@ -259,10 +185,8 @@ ActiveRecord::Schema[8.0].define(version: 2026_06_12_000000) do
     t.datetime "original_created_from"
     t.datetime "original_created_before"
     t.datetime "updated_at", null: false
-    t.integer "version_no", null: false
     t.index ["uploaded_user_id"], name: "index_posts_on_uploaded_user_id"
     t.index ["url"], name: "index_posts_on_url", unique: true
-    t.check_constraint "`version_no` > 0", name: "chk_posts_version_no_positive"
   end
 
   create_table "settings", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
@@ -337,10 +261,8 @@ ActiveRecord::Schema[8.0].define(version: 2026_06_12_000000) do
     t.datetime "updated_at", null: false
     t.integer "post_count", default: 0, null: false
     t.datetime "discarded_at"
-    t.integer "version_no", null: false
     t.index ["discarded_at"], name: "index_tags_on_discarded_at"
     t.index ["tag_name_id"], name: "index_tags_on_tag_name_id", unique: true
-    t.check_constraint "`version_no` > 0", name: "chk_tags_version_no_positive"
   end
 
   create_table "theatre_comments", primary_key: ["theatre_id", "no"], charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
@@ -356,55 +278,6 @@ 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
@@ -459,10 +332,9 @@ ActiveRecord::Schema[8.0].define(version: 2026_06_12_000000) do
     t.string "name"
     t.string "inheritance_code", limit: 64, null: false
     t.string "role", null: false
-    t.datetime "banned_at"
+    t.boolean "banned", default: false, null: false
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
-    t.index ["banned_at"], name: "index_users_on_banned_at"
   end
 
   create_table "wiki_assets", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
@@ -495,12 +367,10 @@ ActiveRecord::Schema[8.0].define(version: 2026_06_12_000000) do
     t.datetime "updated_at", null: false
     t.datetime "discarded_at"
     t.integer "next_asset_no", default: 1, null: false
-    t.integer "version_no", null: false
     t.index ["created_user_id"], name: "index_wiki_pages_on_created_user_id"
     t.index ["discarded_at"], name: "index_wiki_pages_on_discarded_at"
     t.index ["tag_name_id"], name: "index_wiki_pages_on_tag_name_id", unique: true
     t.index ["updated_user_id"], name: "index_wiki_pages_on_updated_user_id"
-    t.check_constraint "`version_no` > 0", name: "chk_wiki_pages_version_no_positive"
   end
 
   create_table "wiki_revision_lines", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
@@ -551,18 +421,6 @@ 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"
@@ -598,18 +456,6 @@ 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/ip_addresses.rb

@@ -1,10 +0,0 @@
-FactoryBot.define do
-  factory :ip_address do
-    ip_address { IPAddr.new('203.0.113.10').hton }
-    banned_at { nil }
-
-    trait :banned do
-      banned_at { Time.current }
-    end
-  end
-end

backend/spec/factories/users.rb

@@ -1,24 +1,15 @@
 FactoryBot.define do
   factory :user do
-    name { nil }
+    name { "test-user" }
     inheritance_code { SecureRandom.uuid }
-    role { 'guest' }
+    role { "guest" }
-    banned_at { nil }
-
-    trait :guest do
-      role { 'guest' }
-    end
 
     trait :member do
-      role { 'member' }
+      role { "member" }
     end
 
     trait :admin do
       role { 'admin' }
     end
-
-    trait :banned do
-      banned_at { Time.current }
-    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

@@ -1,75 +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 not found without an admin 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(:not_found)
-    end
-
-    it 'returns not found 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(:not_found)
-    end
-  end
-end

backend/spec/requests/gekanator_learning_spec.rb

@@ -1,612 +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 'returns not found 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(:not_found)
-    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 'returns not found for a non-admin user' do
-      sign_in_as member
-
-      post '/gekanator/question_suggestions', params: {
-        gekanator_game_id: game.id,
-        question_text: 'member question?',
-        answer: 'yes'
-      }
-
-      expect(response).to have_http_status(:not_found)
-    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
-  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
-  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
-  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

@@ -10,10 +10,6 @@ RSpec.describe 'Posts API', type: :request do
     allow_any_instance_of(Post).to receive(:resized_thumbnail!).and_return(true)
   end
 
-  def create_nico_tag!(name)
-    Tag.find_or_create_by_tag_name!(name, category: :nico)
-  end
-
   def dummy_upload
     # 中身は何でもいい（加工処理はスタブしてる）
     Rack::Test::UploadedFile.new(StringIO.new('dummy'), 'image/jpeg', original_filename: 'dummy.jpg')
@@ -27,8 +23,7 @@ RSpec.describe 'Posts API', type: :request do
     Post.create!(title:, url:)
   end
 
-  def create_post_version_for!(post)
+  def create_post_version_for! post
-    version =
     PostVersion.create!(
       post:,
       version_no: 1,
@@ -41,37 +36,8 @@ RSpec.describe 'Posts API', type: :request do
       original_created_from: post.original_created_from,
       original_created_before: post.original_created_before,
       created_at: post.created_at,
-            created_by_user: post.uploaded_user)
+      created_by_user: post.uploaded_user
-
+    )
-    post.update_columns(version_no: version.version_no) if post.has_attribute?(:version_no)
-    post.version_no = version.version_no if post.respond_to?(:version_no=)
-
-    version
-  end
-
-  def post_update_params(post, params = { })
-    base_version =
-        post.post_versions.order(version_no: :desc).first ||
-        create_post_version_for!(post.reload)
-
-    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') }
@@ -575,59 +541,6 @@ 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 +617,7 @@ 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 +627,7 @@ 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
 
@@ -899,26 +806,24 @@ RSpec.describe 'Posts API', type: :request do
 
     it '401 when not logged in' do
       sign_out
-      put "/posts/#{post_record.id}", params: post_update_params(
+      put "/posts/#{post_record.id}", params: post_write_params(title: 'updated', tags: 'spec_tag')
-          post_record, title: 'updated', tags: 'spec_tag')
       expect(response).to have_http_status(:unauthorized)
     end
 
     it '403 when not member' do
       sign_in_as(create(:user, role: 'guest'))
-      put "/posts/#{post_record.id}", params: post_update_params(
+      put "/posts/#{post_record.id}", params: post_write_params(title: 'updated', tags: 'spec_tag')
-          post_record, title: 'updated', tags: 'spec_tag')
       expect(response).to have_http_status(:forbidden)
     end
 
     it '200 and updates title + resync tags when member' do
       sign_in_as(member)
 
+      # 追加で別タグも作って、更新時に入れ替わることを見る
       tn2 = TagName.create!(name: 'spec_tag_2')
       Tag.create!(tag_name: tn2, category: :general)
 
-      put "/posts/#{post_record.id}", params: post_update_params(
+      put "/posts/#{post_record.id}", params: post_write_params(
-          post_record,
           title: 'updated title',
           tags: 'spec_tag_2')
 
@@ -926,6 +831,7 @@ RSpec.describe 'Posts API', type: :request do
       expect(json).to have_key('tags')
       expect(json['tags']).to be_an(Array)
 
+      # show と同様、update 後レスポンスもツリー形式
       names = json['tags'].map { |n| n['name'] }
       expect(names).to include('spec_tag_2')
     end
@@ -937,21 +843,15 @@ 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(
+        put "/posts/#{post_record.id}", params: post_write_params(
-            post_record,
           title: 'updated title',
-            tags: 'nico:nico_tag')
+          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
 
@@ -987,11 +887,11 @@ RSpec.describe 'Posts API', type: :request do
       it 'replaces parent posts' do
         sign_in_as(member)
 
-        put "/posts/#{post_record.id}", params: post_update_params(
+        put "/posts/#{post_record.id}", params: post_write_params(
-            post_record,
           title: 'updated title',
           tags: 'spec_tag',
-            parent_post_ids: "#{new_parent_post_1.id} #{new_parent_post_2.id}")
+          parent_post_ids: "#{new_parent_post_1.id} #{new_parent_post_2.id}"
+        )
 
         expect(response).to have_http_status(:ok)
 
@@ -1008,8 +908,7 @@ RSpec.describe 'Posts API', type: :request do
       it 'clears parent posts when parent_post_ids is blank' do
         sign_in_as(member)
 
-        put "/posts/#{post_record.id}", params: post_update_params(
+        put "/posts/#{post_record.id}", params: post_write_params(
-          post_record,
           title: 'updated title',
           tags: 'spec_tag',
           parent_post_ids: ''
@@ -1023,8 +922,7 @@ RSpec.describe 'Posts API', type: :request do
         sign_in_as(member)
         create_post_version_for!(post_record.reload)
 
-        put "/posts/#{post_record.id}", params: post_update_params(
+        put "/posts/#{post_record.id}", params: post_write_params(
-          post_record,
           title: 'updated title',
           tags: 'spec_tag',
           parent_post_ids: "#{new_parent_post_1.id} #{new_parent_post_2.id}"
@@ -1045,10 +943,7 @@ RSpec.describe 'Posts API', type: :request do
       it 'returns 422' do
         sign_in_as(member)
 
-        base_version = create_post_version_for!(post_record.reload)
-
         put "/posts/#{post_record.id}", params: {
-            base_version_no: base_version.version_no,
             title: 'updated title',
             tags: 'spec_tag' }
 
@@ -1071,8 +966,7 @@ RSpec.describe 'Posts API', type: :request do
           parent_post:
         )
 
-        put "/posts/#{post_record.id}", params: post_update_params(
+        put "/posts/#{post_record.id}", params: post_write_params(
-          post_record,
           title: 'updated title',
           tags: 'spec_tag',
           parent_post_ids: 'abc'
@@ -1097,8 +991,7 @@ RSpec.describe 'Posts API', type: :request do
           parent_post:
         )
 
-        put "/posts/#{post_record.id}", params: post_update_params(
+        put "/posts/#{post_record.id}", params: post_write_params(
-          post_record,
           title: 'updated title',
           tags: 'spec_tag',
           parent_post_ids: '999999999'
@@ -1113,8 +1006,7 @@ RSpec.describe 'Posts API', type: :request do
       it 'returns 422 and does not create self implication' do
         sign_in_as(member)
 
-        put "/posts/#{post_record.id}", params: post_update_params(
+        put "/posts/#{post_record.id}", params: post_write_params(
-          post_record,
           title: 'updated title',
           tags: 'spec_tag',
           parent_post_ids: post_record.id.to_s
@@ -1128,221 +1020,6 @@ RSpec.describe 'Posts API', type: :request do
         )).to be(false)
       end
     end
-
-    context 'with optimistic locking' do
-      let!(:no_deerjikist_tag) { Tag.no_deerjikist }
-
-      before do
-        PostTag.create!(post: post_record, tag: no_deerjikist_tag)
-      end
-
-      it '400 when base_version_no is missing without force' do
-        sign_in_as(member)
-
-        put "/posts/#{post_record.id}", params: post_write_params(
-            title: 'updated title',
-            tags: 'spec_tag')
-
-        expect(response).to have_http_status(:bad_request)
-      end
-
-      it '400 when force and merge are both true' do
-        sign_in_as(member)
-
-        put "/posts/#{post_record.id}", params: post_write_params(
-            title: 'updated title',
-            tags: 'spec_tag',
-            force: '1',
-            merge: '1')
-
-        expect(response).to have_http_status(:bad_request)
-      end
-
-      it '409 when scalar fields are changed both by current and incoming updates' do
-        sign_in_as(member)
-
-        base_version = create_post_version_for!(post_record.reload)
-
-        post_record.update!(title: 'updated by other user')
-        PostVersionRecorder.record!(
-            post: post_record.reload,
-            event_type: :update,
-            created_by_user: member)
-
-        put "/posts/#{post_record.id}", params: post_write_params(
-            base_version_no: base_version.version_no,
-            title: 'updated by me',
-            tags: "spec_tag #{Tag.no_deerjikist.name}")
-
-        expect(response).to have_http_status(:conflict)
-
-        expect(json.fetch('error')).to eq('conflict')
-        expect(json.fetch('base_version_no')).to eq(base_version.version_no)
-        expect(json.fetch('current_version_no')).to eq(2)
-        expect(json.fetch('mergeable')).to be(false)
-
-        conflict_fields = json.fetch('conflicts').map { |change| change.fetch('field') }
-        expect(conflict_fields).to include('title')
-
-        expect(post_record.reload.title).to eq('updated by other user')
-      end
-
-      it 'returns 409 with mergeable true when stale tag changes do not conflict but merge is not requested' do
-        sign_in_as(member)
-
-        base_version = create_post_version_for!(post_record.reload)
-
-        current_tag = Tag.find_or_create_by_tag_name!('current_added_tag', category: :general)
-        PostTag.create!(post: post_record, tag: current_tag, created_user: member)
-
-        PostVersionRecorder.record!(
-            post: post_record.reload,
-            event_type: :update,
-            created_by_user: member)
-
-        put "/posts/#{post_record.id}", params: post_write_params(
-            base_version_no: base_version.version_no,
-            title: post_record.title,
-            tags: "spec_tag #{Tag.no_deerjikist.name} incoming_added_tag")
-
-        expect(response).to have_http_status(:conflict)
-
-        expect(json.fetch('mergeable')).to be(true)
-
-        tag_change = json.fetch('changes').find { |change| change.fetch('field') == 'tag_names' }
-        expect(tag_change).to be_present
-        expect(tag_change.fetch('conflict')).to be(false)
-        expect(tag_change.fetch('added_by_current')).to include('current_added_tag')
-        expect(tag_change.fetch('added_by_me')).to include('incoming_added_tag')
-      end
-
-      it 'merges non-conflicting stale tag changes when merge is true' do
-        sign_in_as(member)
-
-        base_version = create_post_version_for!(post_record.reload)
-
-        current_tag = Tag.find_or_create_by_tag_name!('current_merge_tag', category: :general)
-        PostTag.create!(post: post_record, tag: current_tag, created_user: member)
-
-        PostVersionRecorder.record!(
-            post: post_record.reload,
-            event_type: :update,
-            created_by_user: member)
-
-        put "/posts/#{post_record.id}", params: post_write_params(
-            base_version_no: base_version.version_no,
-            title: post_record.title,
-            tags: "spec_tag #{Tag.no_deerjikist.name} incoming_merge_tag",
-            merge: '1')
-
-        expect(response).to have_http_status(:ok)
-
-        names = post_record.reload.tags.map(&:name)
-
-        expect(names).to include('spec_tag')
-        expect(names).to include(Tag.no_deerjikist.name)
-        expect(names).to include('current_merge_tag')
-        expect(names).to include('incoming_merge_tag')
-      end
-
-      it 'does not conflict when only nico tags changed after the base version' do
-        sign_in_as(member)
-
-        base_version = create_post_version_for!(post_record.reload)
-
-        nico_tag = create_nico_tag!('nico:optimistic_lock_nico')
-        PostTag.create!(post: post_record, tag: nico_tag, created_user: member)
-
-        PostVersionRecorder.record!(
-            post: post_record.reload,
-            event_type: :update,
-            created_by_user: member)
-
-        expect(post_record.reload.version_no).to eq(2)
-
-        put "/posts/#{post_record.id}", params: post_write_params(
-            base_version_no: base_version.version_no,
-            title: post_record.title,
-            tags: "spec_tag #{ Tag.no_deerjikist.name }")
-
-        expect(response).to have_http_status(:ok)
-
-        names = post_record.reload.tags.map(&:name)
-
-        expect(names).to include('spec_tag')
-        expect(names).to include(Tag.no_deerjikist.name)
-        expect(names).to include(nico_tag.name)
-      end
-
-      it 'keeps nico tags even when they are not included in PUT tags' do
-        sign_in_as(member)
-
-        nico_tag = create_nico_tag!('nico:readonly_update_nico')
-        PostTag.create!(post: post_record, tag: nico_tag, created_user: member)
-
-        base_version = create_post_version_for!(post_record.reload)
-
-        put "/posts/#{post_record.id}", params: post_write_params(
-            base_version_no: base_version.version_no,
-            title: 'updated title',
-            tags: "spec_tag #{ Tag.no_deerjikist.name }")
-
-        expect(response).to have_http_status(:ok)
-
-        names = post_record.reload.tags.map(&:name)
-
-        expect(names).to include('spec_tag')
-        expect(names).to include(Tag.no_deerjikist.name)
-        expect(names).to include(nico_tag.name)
-      end
-
-      it 'allows non-nico tags linked from nico tags to be removed by normal post update' do
-        sign_in_as(member)
-
-        nico_tag = create_nico_tag!('nico:relation_source')
-        linked_tag = Tag.find_or_create_by_tag_name!('relation_linked_tag', category: :general)
-
-        NicoTagRelation.create!(nico_tag:, tag: linked_tag)
-        PostTag.create!(post: post_record, tag: nico_tag, created_user: member)
-        PostTag.create!(post: post_record, tag: linked_tag, created_user: member)
-
-        base_version = create_post_version_for!(post_record.reload)
-
-        put "/posts/#{post_record.id}", params: post_write_params(
-            base_version_no: base_version.version_no,
-            title: post_record.title,
-            tags: "spec_tag #{ Tag.no_deerjikist.name }")
-
-        expect(response).to have_http_status(:ok)
-
-        names = post_record.reload.tags.map(&:name)
-
-        expect(names).to include(nico_tag.name)
-        expect(names).to include('spec_tag')
-        expect(names).to include(Tag.no_deerjikist.name)
-        expect(names).not_to include(linked_tag.name)
-      end
-
-      it 'force-updates stale posts without base_version_no' do
-        sign_in_as(member)
-
-        create_post_version_for!(post_record.reload)
-
-        post_record.update!(title: 'updated by other user')
-        PostVersionRecorder.record!(
-            post: post_record.reload,
-            event_type: :update,
-            created_by_user: member)
-
-        put "/posts/#{post_record.id}", params: post_write_params(
-            title: 'forced title',
-            tags: "spec_tag #{Tag.no_deerjikist.name}",
-            force: '1')
-
-        expect(response).to have_http_status(:ok)
-        expect(post_record.reload.title).to eq('forced title')
-      end
-    end
   end
 
   describe 'GET /posts/random' do
@@ -1757,14 +1434,13 @@ RSpec.describe 'Posts API', type: :request do
 
     it 'creates next version on PUT /posts/:id when snapshot changes' do
       sign_in_as(member)
-      base_version = create_post_version_for!(post_record)
+      create_post_version_for!(post_record)
 
       tag_name2 = TagName.create!(name: 'spec_tag_2')
       Tag.create!(tag_name: tag_name2, category: :general)
 
       expect do
         put "/posts/#{post_record.id}", params: post_write_params(
-            base_version_no: base_version.version_no,
             title: 'updated title',
             tags: 'spec_tag_2')
       end.to change(PostVersion, :count).by(1)
@@ -1783,15 +1459,13 @@ RSpec.describe 'Posts API', type: :request do
       sign_in_as(member)
 
       PostTag.create!(post: post_record, tag: Tag.no_deerjikist)
-      base_version = create_post_version_for!(post_record.reload)
+      create_post_version_for!(post_record.reload)
 
       expect {
         put "/posts/#{post_record.id}", params: post_write_params(
-            base_version_no: base_version.version_no,
             title: post_record.title,
             tags: 'spec_tag')
       }.not_to change(PostVersion, :count)
-
       expect(response).to have_http_status(:ok)
 
       version = post_record.reload.post_versions.order(:version_no).last
@@ -1816,11 +1490,10 @@ RSpec.describe 'Posts API', type: :request do
 
     it 'does not create a version when PUT /posts/:id is invalid' do
       sign_in_as(member)
-      base_version = create_post_version_for!(post_record)
+      create_post_version_for!(post_record)
 
       expect do
         put "/posts/#{post_record.id}", params: post_write_params(
-            base_version_no: base_version.version_no,
             title: 'updated title',
             tags: 'spec_tag',
             original_created_from: Time.zone.local(2020, 1, 2, 0, 0, 0).iso8601,
@@ -1834,22 +1507,46 @@ RSpec.describe 'Posts API', type: :request do
   describe 'tag versioning from post write actions' do
     let(:member) { create(:user, :member) }
 
-    it 'creates tag snapshot for normalised tags on PUT /posts/:id' do
+    it 'creates tag snapshot for normalised tags on POST /posts' do
       sign_in_as(member)
 
-      base_version = create_post_version_for!(post_record.reload)
+      expect {
+        post '/posts', params: post_write_params(
+            title: 'tag versioned post',
+            url: 'https://example.com/tag-versioned-post',
+            tags: 'spec_tag',
+            thumbnail: dummy_upload)
+      }.to change { tag.reload.tag_versions.count }.by(1)
+
+      expect(response).to have_http_status(:created)
+
+      version = tag.reload.tag_versions.order(:version_no).last
+      expect(version.version_no).to eq(1)
+      expect(version.event_type).to eq('create')
+      expect(version.name).to eq('spec_tag')
+      expect(version.category).to eq('general')
+      expect(version.created_by_user_id).to eq(member.id)
+    end
+
+    it 'creates tag snapshot for normalised tags on PUT /posts/:id' do
+      sign_in_as(member)
 
       tag_name2 = TagName.create!(name: 'spec_tag_2')
       tag2 = Tag.create!(tag_name: tag_name2, category: :general)
 
       expect {
         put "/posts/#{post_record.id}", params: post_write_params(
-            base_version_no: base_version.version_no,
             title: 'updated title',
             tags: 'spec_tag_2')
       }.to change { tag2.reload.tag_versions.count }.by(1)
 
-      expect(response).to have_http_status(:ok), response.body
+      expect(response).to have_http_status(:ok)
+
+      version = tag2.reload.tag_versions.order(:version_no).last
+      expect(version.version_no).to eq(1)
+      expect(version.event_type).to eq('create')
+      expect(version.name).to eq('spec_tag_2')
+      expect(version.created_by_user_id).to eq(member.id)
     end
   end
 end

backend/spec/requests/tag_versions_spec.rb

@@ -26,7 +26,6 @@ RSpec.describe 'TagVersions API', type: :request do
     created_by_user:,
     created_at:
   )
-    version =
     TagVersion.create!(
       tag: tag,
       version_no: version_no,
@@ -36,12 +35,8 @@ RSpec.describe 'TagVersions API', type: :request do
       aliases: Array(aliases).join(' '),
       parent_tag_ids: Array(parent_tags).map(&:id).join(' '),
       created_by_user: created_by_user,
-            created_at: created_at)
+      created_at: created_at
-
+    )
-    tag.update_columns(version_no: version_no) if tag.has_attribute?(:version_no)
-    tag.version_no = version_no if tag.respond_to?(:version_no=)
-
-    version
   end
 
   let!(:v1) do

backend/spec/requests/tags_deerjikists_spec.rb

@@ -8,35 +8,23 @@ RSpec.describe 'Tags deerjikists API', type: :request do
 
   let!(:tag) { create(:tag, category: :deerjikist) }
 
-  let(:member) { create(:user, :member) }
-  let(:guest) { create(:user, role: :guest) }
-
   before do
+    # show_by_name / deerjikists_by_name 用に名前を固定
     tag.tag_name.update!(name: 'deerjika')
   end
 
   describe 'GET /tags/:id/deerjikists' do
     subject(:do_request) do
-      get "/tags/#{tag_id}/deerjikists"
+      get "/tags/#{ tag_id }/deerjikists"
     end
 
     let(:tag_id) { tag.id }
 
     context 'when tag exists and has no deerjikists' do
-      it 'returns 200 with tag and empty deerjikists array' do
+      it 'returns 200 and empty array' do
         do_request
-
         expect(response).to have_http_status(:ok)
-
+        expect(json).to eq([])
-        expect(json).to be_a(Hash)
-
-        expect(json['tag']).to be_a(Hash)
-        expect(json['tag']['id']).to eq(tag.id)
-        expect(json['tag']['name']).to eq('deerjika')
-        expect(json['tag']['category']).to eq('deerjikist')
-        expect(json['tag']['has_deerjikists']).to eq(false)
-
-        expect(json['deerjikists']).to eq([])
       end
     end
 
@@ -46,24 +34,14 @@ RSpec.describe 'Tags deerjikists API', type: :request do
         Deerjikist.create!(platform: platform2, code: code2, tag: tag)
       end
 
-      it 'returns 200 with tag and deerjikists array' do
+      it 'returns 200 and deerjikists array' do
         do_request
-
         expect(response).to have_http_status(:ok)
 
-        expect(json).to be_a(Hash)
+        expect(json).to be_a(Array)
+        expect(json.size).to eq(2)
 
-        expect(json['tag']).to be_a(Hash)
+        expect(json.map { |h| [h['platform'], h['code']] }).to contain_exactly(
-        expect(json['tag']['id']).to eq(tag.id)
-        expect(json['tag']['name']).to eq('deerjika')
-        expect(json['tag']['category']).to eq('deerjikist')
-        expect(json['tag']['has_deerjikists']).to eq(true)
-
-        expect(json['deerjikists']).to be_a(Array)
-        expect(json['deerjikists'].size).to eq(2)
-
-        expect(json['deerjikists'].map { |h| [h['platform'], h['code']] })
-          .to contain_exactly(
           [platform1, code1],
           [platform2, code2],
         )
@@ -75,7 +53,6 @@ RSpec.describe 'Tags deerjikists API', type: :request do
 
       it 'returns 404' do
         do_request
-
         expect(response).to have_http_status(:not_found)
       end
     end
@@ -83,7 +60,7 @@ RSpec.describe 'Tags deerjikists API', type: :request do
 
   describe 'GET /tags/name/:name/deerjikists' do
     subject(:do_request) do
-      get "/tags/name/#{name}/deerjikists"
+      get "/tags/name/#{ name }/deerjikists"
     end
 
     let(:name) { 'deerjika' }
@@ -93,7 +70,6 @@ RSpec.describe 'Tags deerjikists API', type: :request do
 
       it 'returns 400' do
         do_request
-
         expect(response).to have_http_status(:bad_request)
       end
     end
@@ -103,233 +79,23 @@ RSpec.describe 'Tags deerjikists API', type: :request do
 
       it 'returns 404' do
         do_request
-
         expect(response).to have_http_status(:not_found)
       end
     end
 
-    context 'when tag exists and has no deerjikists' do
-      it 'returns 200 with tag and empty deerjikists array' do
-        do_request
-
-        expect(response).to have_http_status(:ok)
-
-        expect(json).to be_a(Hash)
-
-        expect(json['tag']).to be_a(Hash)
-        expect(json['tag']['id']).to eq(tag.id)
-        expect(json['tag']['name']).to eq('deerjika')
-        expect(json['tag']['category']).to eq('deerjikist')
-        expect(json['tag']['has_deerjikists']).to eq(false)
-
-        expect(json['deerjikists']).to eq([])
-      end
-    end
-
     context 'when tag exists and has deerjikists' do
       before do
         Deerjikist.create!(platform: platform1, code: code1, tag: tag)
       end
 
-      it 'returns 200 with tag and deerjikists array' do
+      it 'returns 200 and deerjikists array' do
         do_request
-
         expect(response).to have_http_status(:ok)
 
-        expect(json).to be_a(Hash)
-
-        expect(json['tag']).to be_a(Hash)
-        expect(json['tag']['id']).to eq(tag.id)
-        expect(json['tag']['name']).to eq('deerjika')
-        expect(json['tag']['category']).to eq('deerjikist')
-        expect(json['tag']['has_deerjikists']).to eq(true)
-
-        expect(json['deerjikists']).to be_a(Array)
-        expect(json['deerjikists'].size).to eq(1)
-
-        expect(json['deerjikists'][0]['platform']).to eq(platform1)
-        expect(json['deerjikists'][0]['code']).to eq(code1)
-      end
-    end
-  end
-
-  describe 'PUT /tags/:id/deerjikists' do
-    subject(:do_request) do
-      put "/tags/#{tag_id}/deerjikists", params: payload, as: :json
-    end
-
-    let(:tag_id) { tag.id }
-    let(:payload) do
-      [
-        { platform: platform1, code: code1 },
-        { platform: platform2, code: code2 },
-      ]
-    end
-
-    context 'when not logged in' do
-      it 'returns 401' do
-        do_request
-
-        expect(response).to have_http_status(:unauthorized)
-      end
-    end
-
-    context 'when logged in but not member' do
-      before do
-        sign_in_as guest
-      end
-
-      it 'returns 403' do
-        do_request
-
-        expect(response).to have_http_status(:forbidden)
-      end
-    end
-
-    context 'when tag does not exist' do
-      let(:tag_id) { 9_999_999 }
-
-      before do
-        sign_in_as member
-      end
-
-      it 'returns 404' do
-        do_request
-
-        expect(response).to have_http_status(:not_found)
-      end
-    end
-
-    context 'when logged in as member' do
-      before do
-        sign_in_as member
-      end
-
-      context 'when tag has no deerjikists' do
-        it 'creates deerjikists and returns deerjikists array' do
-          expect {
-            do_request
-          }.to change { Deerjikist.where(tag: tag).count }.from(0).to(2)
-
-          expect(response).to have_http_status(:ok)
-
-          expect(json).to be_a(Array)
-          expect(json.map { |h| [h['platform'], h['code']] })
-            .to contain_exactly(
-              [platform1, code1],
-              [platform2, code2],
-            )
-
-          expect(Deerjikist.where(tag: tag).map { |d| [d.platform, d.code] })
-            .to contain_exactly(
-              [platform1, code1],
-              [platform2, code2],
-            )
-        end
-      end
-
-      context 'when tag already has deerjikists' do
-        before do
-          Deerjikist.create!(platform: platform1, code: 'old-code-1', tag: tag)
-          Deerjikist.create!(platform: platform2, code: 'old-code-2', tag: tag)
-        end
-
-        it 'replaces deerjikists and returns deerjikists array' do
-          do_request
-
-          expect(response).to have_http_status(:ok)
-
-          expect(Deerjikist.where(tag: tag).map { |d| [d.platform, d.code] })
-            .to contain_exactly(
-              [platform1, code1],
-              [platform2, code2],
-            )
-
-          expect(Deerjikist.exists?(platform: platform1, code: 'old-code-1')).to eq(false)
-          expect(Deerjikist.exists?(platform: platform2, code: 'old-code-2')).to eq(false)
-
-          expect(json).to be_a(Array)
-          expect(json.map { |h| [h['platform'], h['code']] })
-            .to contain_exactly(
-              [platform1, code1],
-              [platform2, code2],
-            )
-        end
-      end
-
-      context 'when payload is empty array' do
-        let(:payload) { [] }
-
-        before do
-          Deerjikist.create!(platform: platform1, code: code1, tag: tag)
-          Deerjikist.create!(platform: platform2, code: code2, tag: tag)
-        end
-
-        it 'clears deerjikists and returns empty array' do
-          expect {
-            do_request
-          }.to change { Deerjikist.where(tag: tag).count }.from(2).to(0)
-
-          expect(response).to have_http_status(:ok)
-          expect(json).to eq([])
-        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
-          [
-            { platform: 'youtube', code: '@deerjika' },
-          ]
-        end
-
-        before do
-          allow(Net::HTTP).to receive(:get).and_return(
-            %(<link rel="canonical" href="https://www.youtube.com/channel/#{channel_id}">),
-          )
-        end
-
-        it 'normalises youtube handle to channel id' do
-          expect {
-            do_request
-          }.to change { Deerjikist.where(tag: tag).count }.from(0).to(1)
-
-          expect(response).to have_http_status(:ok)
-
-          expect(Net::HTTP).to have_received(:get)
-
-          expect(Deerjikist.exists?(platform: 'youtube', code: channel_id, tag: tag))
-            .to eq(true)
-
         expect(json).to be_a(Array)
         expect(json.size).to eq(1)
-          expect(json[0]['platform']).to eq('youtube')
+        expect(json[0]['platform']).to eq(platform1)
-          expect(json[0]['code']).to eq(channel_id)
+        expect(json[0]['code']).to eq(code1)
-        end
       end
     end
   end

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

@@ -1,268 +1,109 @@
-require 'rails_helper'
+require "rails_helper"
-
-RSpec.describe 'Users', type: :request do
-  let(:remote_ip) { '203.0.113.10' }
-
-  before do
-    allow_any_instance_of(ActionDispatch::Request)
-      .to receive(:remote_ip)
-      .and_return(remote_ip)
-  end
-
-  def auth_headers(user)
-    { 'X-Transfer-Code' => user.inheritance_code }
-  end
-
-  describe 'POST /users' do
-    it 'creates guest user, IpAddress and UserIp, and returns code' do
-      expect {
-        post '/users'
-      }.to change(User, :count).by(1)
-        .and change(IpAddress, :count).by(1)
-        .and change(UserIp, :count).by(1)
 
+RSpec.describe "Users", type: :request do
+  describe "POST /users" do
+    it "creates guest user and returns code" do
+      post "/users"
       expect(response).to have_http_status(:created)
-      expect(json['code']).to be_present
+      expect(json["code"]).to be_present
-      expect(json['user']['role']).to eq('guest')
+      expect(json["user"]["role"]).to eq("guest")
-
-      user = User.last
-      ip_address = IpAddress.find_by(ip_address: IPAddr.new(remote_ip).hton)
-
-      expect(user.role).to eq('guest')
-      expect(ip_address).to be_present
-      expect(UserIp.exists?(user:, ip_address:)).to eq(true)
-    end
-
-    it 'returns 403 and does not create user when current IP address is banned' do
-      IpAddress.create!(
-        ip_address: IPAddr.new(remote_ip).hton,
-        banned_at: Time.current
-      )
-
-      expect {
-        post '/users'
-      }.not_to change(User, :count)
-
-      expect(response).to have_http_status(:forbidden)
-      expect(UserIp.count).to eq(0)
     end
   end
 
-  describe 'POST /users/code/renew' do
+  describe "POST /users/code/renew" do
-    it 'returns 401 when not logged in' do
+    it "returns 401 when not logged in" do
-      post '/users/code/renew'
+      sign_out
+      post "/users/code/renew"
+      expect(response).to have_http_status(:unauthorized)
+    end
+  end
 
+  describe "PUT /users/:id" do
+    let(:user) { create(:user, name: "old-name", role: "guest") }
+
+    it "returns 401 when current_user id mismatch" do
+      sign_in_as(create(:user))
+      put "/users/#{user.id}", params: { name: "new-name" }
       expect(response).to have_http_status(:unauthorized)
     end
 
-    it 'returns 403 when current user is banned' do
+    it "returns 400 when name is blank" do
-      user = create(:user, :banned)
+      sign_in_as(user)
-
+      put "/users/#{user.id}", params: { name: "   " }
-      post '/users/code/renew', headers: auth_headers(user)
+      expect(response).to have_http_status(:bad_request)
-
-      expect(response).to have_http_status(:forbidden)
     end
 
-    it 'returns 403 when current IP address is banned' do
+    it "updates name and returns 201 with user slice" do
-      user = create(:user)
+      sign_in_as(user)
-
+      put "/users/#{user.id}", params: { name: "new-name" }
-      IpAddress.create!(
-        ip_address: IPAddr.new(remote_ip).hton,
-        banned_at: Time.current
-      )
-
-      post '/users/code/renew', headers: auth_headers(user)
-
-      expect(response).to have_http_status(:forbidden)
-    end
-  end
-
-  describe 'PUT /users/:id' do
-    let(:user) { create(:user, name: 'old-name', role: 'guest') }
-
-    it 'returns 401 when current_user id mismatch' do
-      other_user = create(:user)
-
-      put "/users/#{user.id}",
-          params: { name: 'new-name' },
-          headers: auth_headers(other_user)
-
-      expect(response).to have_http_status(:unauthorized)
-    end
-
-    it 'returns 422 when name is blank' do
-      put "/users/#{user.id}",
-          params: { name: '   ' },
-          headers: auth_headers(user)
-
-      expect(response).to have_http_status(:unprocessable_entity)
-      expect(json.fetch('errors')).to include(
-          'name' => ['名前は必須です．'])
-    end
-
-    it 'updates name and returns user slice' do
-      put "/users/#{user.id}",
-          params: { name: 'new-name' },
-          headers: auth_headers(user)
 
       expect(response).to have_http_status(:ok)
-      expect(json['id']).to eq(user.id)
+      expect(json["id"]).to eq(user.id)
-      expect(json['name']).to eq('new-name')
+      expect(json["name"]).to eq("new-name")
 
       user.reload
-      expect(user.name).to eq('new-name')
+      expect(user.name).to eq("new-name")
-    end
-
-    it 'returns 403 when current user is banned' do
-      user.update!(banned_at: Time.current)
-
-      put "/users/#{user.id}",
-          params: { name: 'new-name' },
-          headers: auth_headers(user)
-
-      expect(response).to have_http_status(:forbidden)
-
-      user.reload
-      expect(user.name).to eq('old-name')
-    end
-
-    it 'returns 403 when current IP address is banned' do
-      IpAddress.create!(
-        ip_address: IPAddr.new(remote_ip).hton,
-        banned_at: Time.current
-      )
-
-      put "/users/#{user.id}",
-          params: { name: 'new-name' },
-          headers: auth_headers(user)
-
-      expect(response).to have_http_status(:forbidden)
-
-      user.reload
-      expect(user.name).to eq('old-name')
     end
   end
 
-  describe 'POST /users/verify' do
+  describe "POST /users/verify" do
-    it 'returns valid:false when code not found' do
+    it "returns valid:false when code not found" do
-      post '/users/verify', params: { code: 'nope' }
+      post "/users/verify", params: { code: "nope" }
-
       expect(response).to have_http_status(:ok)
-      expect(json['valid']).to eq(false)
+      expect(json["valid"]).to eq(false)
     end
 
-    it 'returns 403 when current IP address is banned' do
+    it "creates IpAddress and UserIp, and returns valid:true with user slice" do
-      user = create(:user, inheritance_code: SecureRandom.uuid, role: 'guest')
+      user = create(:user, inheritance_code: SecureRandom.uuid, role: "guest")
 
-      IpAddress.create!(
+      # request.remote_ip を固定
-        ip_address: IPAddr.new(remote_ip).hton,
+      allow_any_instance_of(ActionDispatch::Request).to receive(:remote_ip).and_return("203.0.113.10")
-        banned_at: Time.current
-      )
 
       expect {
-        post '/users/verify', params: { code: user.inheritance_code }
+        post "/users/verify", params: { code: user.inheritance_code }
-      }.not_to change(UserIp, :count)
-
-      expect(response).to have_http_status(:forbidden)
-    end
-
-    it 'returns 403 when verified user is banned' do
-      user = create(
-        :user,
-        :banned,
-        inheritance_code: SecureRandom.uuid,
-        role: 'guest'
-      )
-
-      expect {
-        post '/users/verify', params: { code: user.inheritance_code }
-      }.not_to change(UserIp, :count)
-
-      expect(response).to have_http_status(:forbidden)
-    end
-
-    it 'creates IpAddress and UserIp, and returns valid:true with user slice' do
-      user = create(:user, inheritance_code: SecureRandom.uuid, role: 'guest')
-
-      expect {
-        post '/users/verify', params: { code: user.inheritance_code }
-      }.to change(UserIp, :count).by(1)
-        .and change(IpAddress, :count).by(1)
-
-      expect(response).to have_http_status(:ok)
-      expect(json['valid']).to eq(true)
-      expect(json['user']['id']).to eq(user.id)
-      expect(json['user']['inheritance_code']).to eq(user.inheritance_code)
-      expect(json['user']['role']).to eq('guest')
-
-      ip_address = IpAddress.find_by(ip_address: IPAddr.new(remote_ip).hton)
-      expect(ip_address).to be_present
-      expect(UserIp.exists?(user:, ip_address:)).to eq(true)
-    end
-
-    it 'is idempotent for same user and same IP address' do
-      user = create(:user, inheritance_code: SecureRandom.uuid, role: 'guest')
-
-      post '/users/verify', params: { code: user.inheritance_code }
-      expect(response).to have_http_status(:ok)
-
-      expect {
-        post '/users/verify', params: { code: user.inheritance_code }
-      }.not_to change(UserIp, :count)
-
-      expect(response).to have_http_status(:ok)
-      expect(json['valid']).to eq(true)
-    end
-
-    it 'creates another UserIp for same user and different IP address' do
-      user = create(:user, inheritance_code: SecureRandom.uuid, role: 'guest')
-
-      post '/users/verify', params: { code: user.inheritance_code }
-      expect(response).to have_http_status(:ok)
-
-      allow_any_instance_of(ActionDispatch::Request)
-        .to receive(:remote_ip)
-        .and_return('203.0.113.11')
-
-      expect {
-        post '/users/verify', params: { code: user.inheritance_code }
       }.to change(UserIp, :count).by(1)
 
       expect(response).to have_http_status(:ok)
-      expect(json['valid']).to eq(true)
+      expect(json["valid"]).to eq(true)
+      expect(json["user"]["id"]).to eq(user.id)
+      expect(json["user"]["inheritance_code"]).to eq(user.inheritance_code)
+      expect(json["user"]["role"]).to eq("guest")
+
+      # ついでに IpAddress もできてることを確認（ipの保存形式がバイナリでも count で見れる）
+      expect(IpAddress.count).to be >= 1
+    end
+
+    it "is idempotent for same user+ip (does not create duplicate UserIp)" do
+      user = create(:user, inheritance_code: SecureRandom.uuid, role: "guest")
+      allow_any_instance_of(ActionDispatch::Request).to receive(:remote_ip).and_return("203.0.113.10")
+
+      post "/users/verify", params: { code: user.inheritance_code }
+      expect(response).to have_http_status(:ok)
+
+      expect {
+        post "/users/verify", params: { code: user.inheritance_code }
+      }.not_to change(UserIp, :count)
+
+      expect(response).to have_http_status(:ok)
+      expect(json["valid"]).to eq(true)
     end
   end
 
-  describe 'GET /users/me' do
+  describe "GET /users/me" do
-    it 'returns 404 when code not found' do
+    it "returns 404 when code not found" do
-      get '/users/me', params: { code: 'nope' }
+      get "/users/me", params: { code: "nope" }
-
       expect(response).to have_http_status(:not_found)
     end
 
-    it 'returns user slice when found' do
+    it "returns user slice when found" do
-      user = create(:user, inheritance_code: SecureRandom.uuid, name: 'me', role: 'guest')
+      user = create(:user, inheritance_code: SecureRandom.uuid, name: "me", role: "guest")
-
+      get "/users/me", params: { code: user.inheritance_code }
-      get '/users/me', params: { code: user.inheritance_code }
 
       expect(response).to have_http_status(:ok)
-      expect(json['id']).to eq(user.id)
+      expect(json["id"]).to eq(user.id)
-      expect(json['name']).to eq('me')
+      expect(json["name"]).to eq("me")
-      expect(json['inheritance_code']).to eq(user.inheritance_code)
+      expect(json["inheritance_code"]).to eq(user.inheritance_code)
-      expect(json['role']).to eq('guest')
+      expect(json["role"]).to eq("guest")
-    end
-
-    it 'returns 403 when current IP address is banned' do
-      user = create(:user, inheritance_code: SecureRandom.uuid)
-
-      IpAddress.create!(
-        ip_address: IPAddr.new(remote_ip).hton,
-        banned_at: Time.current
-      )
-
-      get '/users/me', params: { code: user.inheritance_code }
-
-      expect(response).to have_http_status(:forbidden)
     end
   end
 end

backend/spec/services/version_recorder_spec.rb

@@ -1,85 +0,0 @@
-require 'rails_helper'
-
-RSpec.describe VersionRecorder do
-  let(:member) { create(:user, :member) }
-
-  let(:post_record) do
-    Post.create!(
-        title: 'version recorder post',
-        url: 'https://example.com/version-recorder-post')
-  end
-
-  it 'updates record version_no when creating the first version' do
-    version =
-        PostVersionRecorder.record!(
-            post: post_record,
-            event_type: :create,
-            created_by_user: member)
-
-    expect(version.version_no).to eq(1)
-    expect(post_record.reload.version_no).to eq(1)
-  end
-
-  it 'updates record version_no when creating the next version' do
-    PostVersionRecorder.record!(
-        post: post_record,
-        event_type: :create,
-        created_by_user: member)
-
-    post_record.update!(title: 'updated version recorder post')
-
-    version =
-        PostVersionRecorder.record!(
-            post: post_record.reload,
-            event_type: :update,
-            created_by_user: member)
-
-    expect(version.version_no).to eq(2)
-    expect(post_record.reload.version_no).to eq(2)
-  end
-
-  it 'does not create a new version or advance version_no when snapshot is unchanged' do
-    first =
-        PostVersionRecorder.record!(
-            post: post_record,
-            event_type: :create,
-            created_by_user: member)
-
-    expect {
-      version =
-          PostVersionRecorder.record!(
-              post: post_record.reload,
-              event_type: :update,
-              created_by_user: member)
-
-      expect(version).to eq(first)
-    }.not_to change(PostVersion, :count)
-
-    expect(post_record.reload.version_no).to eq(1)
-  end
-
-  it 'raises when record version_no is older than the latest version' do
-    PostVersionRecorder.record!(
-        post: post_record,
-        event_type: :create,
-        created_by_user: member)
-
-    post_record.update!(title: 'updated once')
-
-    PostVersionRecorder.record!(
-        post: post_record.reload,
-        event_type: :update,
-        created_by_user: member)
-
-    post_record.update_columns(version_no: 1)
-
-    post_record.update!(title: 'updated with stale version_no')
-
-    expect {
-      PostVersionRecorder.record!(
-          post: post_record.reload,
-          event_type: :update,
-          created_by_user: member)
-    }.to raise_error(RuntimeError, /version_no/)
-  end
-end

backend/spec/support/test_records.rb

@@ -2,12 +2,14 @@ module TestRecords
   def create_member_user!
     User.create!(name: 'spec user',
                  inheritance_code: SecureRandom.hex(16),
-                 role: 'member')
+                 role: 'member',
+                 banned: false)
   end
 
   def create_admin_user!
     User.create!(name: 'spec admin',
                  inheritance_code: SecureRandom.hex(16),
-                 role: 'admin')
+                 role: 'admin',
+                 banned: false)
   end
 end

docs/codex-handoff.md

@@ -1,646 +0,0 @@
-# Codex handoff for BTRC Hub / タグ広場
-
-This document transfers project-specific context from prior ChatGPT-assisted design and review work to Codex.
-
-Use this file as project background.
-Use `AGENTS.md`, `backend/AGENTS.md`, and `frontend/AGENTS.md` for concrete coding rules and verification commands.
-
-## Project identity
-
-BTRC Hub / タグ広場 is a collaborative knowledge base for collecting, tagging, explaining, and rediscovering Bocchi the Rock creature-related works.
-
-It is not a generic SNS.
-It is not a comment board.
-It is not a service for rehosting external content.
-It is primarily a structured link, tag, wiki, material, and viewing-party system.
-
-Core domains:
-
-1. Posts
-2. Tags
-3. Wiki pages
-4. Materials
-5. Theatre / watch-party features
-
-The project is already publicly accessible and indexed by search engines, but it has not been broadly announced. Treat it as a small public production system, not a private prototype.
-
-## Current stack
-
-Backend:
-
-- Ruby 3.2.2
-- Rails 8.0.2 API
-- MySQL 8
-- Active Storage
-- Cloudflare R2 / S3-compatible storage is expected for uploaded files
-- RSpec
-
-Frontend:
-
-- React 19.1
-- Vite 6.3
-- TypeScript 5.8
-- Axios
-- TanStack Query
-- Tailwind CSS
-- Framer Motion
-- shadcn-like local components
-- react-markdown
-- react-markdown-editor-lite
-- remark-wiki-autolink
-
-Batch / background-like tasks:
-
-- Rake tasks
-- Nico sync
-- YouTube sync
-- Similarity calculation tasks
-
-## Repository working principle
-
-Before editing, inspect the existing implementation.
-
-Do not invent a new architecture when the current repo already has an established convention.
-
-Keep changes scoped to the requested issue.
-
-Prefer small, reviewable changes over broad rewrites.
-
-Do not perform unrelated cleanup in the same patch.
-
-When a task has design ambiguity, first produce a short investigation and recommended plan. Do not silently choose a risky design.
-
-## User coding preferences
-
-General:
-
-- Prefer single quotes for strings unless interpolation, escaping, or framework convention makes double quotes better.
-- Do not add production dependencies without explicit approval.
-- Do not perform broad formatting churn.
-- Do not convert unrelated files to a different style.
-
-Ruby:
-
-- Do not put a space before method-call parentheses.
-- Do not use `%w`.
-- Do not use `%i`.
-- Keep Rails code idiomatic, but preserve the user's style where the repo already uses it.
-
-TypeScript / Python:
-
-- The user prefers GNU-style spacing before parentheses where syntactically valid.
-- Preserve existing project formatting if a formatter or nearby code dictates otherwise.
-
-## Current authentication model
-
-The system does not use normal email/password authentication.
-
-Users are authenticated by inheritance code.
-
-Frontend:
-
-- Stores the code in `localStorage.user_code`.
-- Sends it as the `X-Transfer-Code` header.
-
-Backend:
-
-- Looks up `users.inheritance_code`.
-- Sets `current_user`.
-
-Roles:
-
-- `guest`
-- `member`
-- `admin`
-
-Important helper:
-
-- `User#gte_member?` returns true for `member` and `admin`.
-
-Never introduce a conventional login assumption unless the issue explicitly asks for it.
-
-## BAN / abuse-control model
-
-The backend currently enforces BAN at API level.
-
-The relevant before_action order is conceptually:
-
-1. Reject banned IP address.
-2. Authenticate user if transfer code exists.
-3. Reject banned user.
-
-Entities:
-
-- `users.banned_at`
-- `ip_addresses.banned_at`
-- `user_ips`
-
-IP addresses are stored as binary values using `IPAddr#hton`.
-
-Do not weaken BAN behavior.
-
-Do not move BAN checks behind optional authentication.
-
-Do not make preview, theatre, verify, user creation, or public-looking endpoints bypass BAN without an explicit design decision.
-
-## Public-operation assumptions
-
-Current practical operation:
-
-- A few editor accounts exist.
-- Meaningful editing is mostly done by the owner.
-- Read access is already public.
-- Search engines have indexed the site.
-- Future editor applications are expected through Discord.
-- Prospective editors are likely people known in the Bocchi creature community.
-
-This means security and moderation issues matter even if traffic is still small.
-
-## Core domain summary
-
-### Posts
-
-Posts are external URL-based link records.
-
-Important properties:
-
-- `url` is required and unique.
-- URLs are normalized.
-- Only HTTP / HTTPS are allowed.
-- Posts can have thumbnails through Active Storage.
-- `uploaded_user_id` may be NULL for synced or bot-created posts.
-- `original_created_from` and `original_created_before` represent a time range for original content creation.
-- When both original time bounds exist, `from < before` is required.
-
-Parent/child posts:
-
-- Current implementation uses `post_implications`.
-- It is many-to-many.
-- Do not assume `posts.parent_id`.
-- Frontend/API clients must send `parent_post_ids`, even when empty.
-- `parent_post_ids` is parsed as a space-separated ID string.
-- Self-parenting is invalid.
-- Missing parent IDs are invalid.
-
-Versions:
-
-- `post_versions` stores snapshots.
-- `version_no` is a per-post sequence.
-- Snapshot includes title, URL, thumbnail base, tags, parent post IDs, original time bounds, event type, and actor.
-- Optimistic locking for posts is planned / important, but do not assume it is fully implemented unless the code proves it.
-
-### Tags
-
-Tags are central.
-
-There is separation between tag names and tag entities:
-
-- `tag_names`
-- `tags`
-
-Categories:
-
-- `deerjikist`
-- `meme`
-- `character`
-- `general`
-- `material`
-- `nico`
-- `meta`
-
-Alias model:
-
-- `tag_names.canonical_id` expresses aliases.
-- `canonical_id = NULL` means canonical name.
-- `canonical_id != NULL` means alias.
-- An alias must not point to another alias.
-- A tag name that already has a tag or wiki page generally must not be aliasified.
-
-Tag normalization:
-
-- User-entered tags are normalized through existing backend logic.
-- Known aliases are canonicalized.
-- Parent tags are expanded recursively.
-- `nico:` is normally rejected for manual entry.
-- Special tags such as tag-request / bot / unknown-deerjikist / video / niconico / youtube must be protected.
-
-Do not casually change tag normalization, alias resolution, or parent expansion. These affect search, wiki, sync, and historical data.
-
-### Nico tags
-
-Nico tags use the `nico` category and have separate versioning.
-
-Important relation:
-
-- `nico_tag_relations` maps external Nico tags to internal tags.
-- `nico_tag_id` must be a Nico category tag.
-- `tag_id` must not be Nico category.
-
-Do not allow ordinary manual tag editing to create or corrupt Nico tags.
-
-### Deerjikists
-
-Deerjikists map external platform identities to internal `deerjikist` tags.
-
-Known platforms include:
-
-- `nico`
-- `youtube`
-
-YouTube handles may be normalized to `UC...` channel IDs.
-
-Do not treat user-facing handles and canonical channel IDs as interchangeable without checking existing code.
-
-### Wiki
-
-Wiki pages are a major knowledge layer.
-
-Important points:
-
-- Wiki pages are tied to tag-like titles.
-- Title handling, aliases, and canonical tag names matter.
-- There is line-level storage / revision-oriented behavior in the current implementation.
-- There has been design tension between wiki revisions and wiki versions.
-- Wiki conflict detection using `base_revision_id` exists on the backend side.
-- Frontend support for conflict detection must be verified before assuming it is complete.
-
-Do not redesign Wiki storage casually.
-
-Do not add a second competing history system.
-
-Do not break existing wiki URLs.
-
-### Materials
-
-Materials connect files or reference URLs to `material` or `character` tags.
-
-Important properties:
-
-- A material has a `tag_id`.
-- The tag must be `material` or `character`.
-- A material requires either `url` or attached `file`.
-- Active Storage is involved.
-- Upload/security policy matters more than plain link posting.
-
-Important unresolved/risky area:
-
-- Material creation permissions have historically been risky because upload endpoints can be abused.
-- Prefer `member` or higher for material creation unless the issue explicitly says otherwise.
-
-### Theatre
-
-Theatre is an experimental watch-party style feature.
-
-Known pieces include:
-
-- Display
-- Presence
-- Next post
-- Comments
-- Host-like control
-
-Do not assume theatre has complete CRUD/admin support unless the code proves it.
-
-Theatre may become expensive if next-item selection uses random DB ordering.
-
-## Current high-risk areas
-
-Treat these areas with extra care.
-
-### Security
-
-- Preview API SSRF protection.
-- External iframe / embed CSP.
-- Markdown link safety.
-- BAN / IP BAN bypass.
-- Transfer-code leakage.
-- Guest write access.
-- Upload endpoints.
-- Admin-only tag operations.
-- System tag mutation.
-
-### Data integrity
-
-- Tag alias canonicalization.
-- Tag parent expansion.
-- Post parent many-to-many relationships.
-- Version tables.
-- `version_no` synchronization.
-- Schema drift from branch migration contamination.
-- Wiki revision/version split.
-- Material version recording.
-
-### Frontend correctness
-
-- React Hooks must not be called conditionally.
-- Role guards are currently spread across components/pages.
-- TanStack Query keys must not collide between ID/name or ID/title variants.
-- URL path segments containing tag names or wiki titles must use `encodeURIComponent`.
-- API response types may allow `null` users for bot or migration data.
-- Tag autocomplete has had duplicated logic and stale state hazards.
-
-### Performance
-
-- Avoid unbounded `limit`.
-- Avoid `order('RAND()')` for growing tables.
-- Avoid loading full relations just to count.
-- Avoid Ruby-side sorting/paging for large histories.
-- Tag sidebar client-side aggregation can become expensive.
-- Wiki full-text search needs deliberate indexing/design.
-
-## Current priority order
-
-Use this as the default priority unless an issue says otherwise.
-
-### P0: Safety before broad announcement
-
-1. Preview API SSRF hardening.
-2. Material creation permission tightening.
-3. System tag mutation holes.
-4. `GET /users/me` transfer-code leakage through query params.
-5. Limit caps for index/history/comment APIs.
-6. CSP / iframe sandbox policy.
-7. Confirm BAN enforcement remains global.
-
-### P1: Core correctness
-
-1. Post optimistic locking with `version_no`.
-2. Wiki edit conflict handling.
-3. Wiki history/revision model clarification.
-4. Wiki search truthfulness: implement body search or remove false UI.
-5. Tag alias/canonical/wiki interaction.
-6. Tag URL encoding.
-7. TanStack Query key separation.
-8. Frontend null-user handling.
-9. React Hooks rule fixes.
-10. Material version policy.
-
-### P2: Operational/admin usability
-
-1. Admin screens for users, IPs, bans, aliases, and settings.
-2. Settings table and user settings usage.
-3. Better tag sidebar.
-4. Better role guard helpers.
-5. Better frontend tests.
-6. Better issue triage and closure of already-implemented issues.
-
-### P3: Future features
-
-1. Theatre list/create/edit/admin flow.
-2. Muted/hidden tags.
-3. Tag category custom colors.
-4. Responsive refinements.
-5. Watch-party improvements.
-6. Broader embed support.
-
-## Known issue triage notes
-
-Some existing issues may already be partially or mostly implemented.
-
-Before implementing an issue, check code first.
-
-Examples:
-
-- Tag search and OR/NOT search may already be mostly implemented.
-- BAN enforcement may have been implemented after earlier issue drafts.
-- YouTube sync exists and should not be treated as purely planned.
-- Parent posts are many-to-many in current schema, even if older issues mention one-to-many.
-- Some issues may reflect old schema or old branch state.
-
-When in doubt:
-
-1. Inspect current code.
-2. Inspect schema.
-3. Inspect routes.
-4. Inspect frontend usage.
-5. Report whether the issue is implemented, partially implemented, not implemented, or obsolete.
-6. Only then edit.
-
-## Verification expectations
-
-Backend changes:
-
-- Run RSpec when possible.
-- Add request specs for API behavior changes.
-- Add model specs for validation / normalization changes.
-- Check migrations and schema consistency.
-- Do not silently ignore pending migrations.
-
-Frontend changes:
-
-- Run build.
-- Run lint if configured.
-- Run tests if configured.
-- Add tests for important behavior when the test framework exists.
-- If frontend tests are not yet installed, state that clearly.
-
-Full-stack changes:
-
-- Verify both backend and frontend compile/test paths where possible.
-- Confirm API response shapes match TypeScript types.
-- Confirm authorization behavior on both server and UI.
-
-If commands cannot be run because dependencies are missing, report that explicitly. Do not pretend verification passed.
-
-## Branch / migration caution
-
-The project has previously suffered from schema contamination caused by running migrations from another branch.
-
-Be careful when touching:
-
-- `db/schema.rb`
-- migration files
-- parent post schema
-- banned / banned_at schema
-- version_no migrations
-- wiki asset schema
-
-Before changing migrations:
-
-1. Inspect current schema.
-2. Inspect existing migrations.
-3. Confirm whether the intended branch already includes related migrations.
-4. Prefer additive migrations for shared branches.
-5. Do not edit already-applied production migrations unless explicitly instructed.
-
-## API design principles
-
-Prefer explicit server-side authorization.
-
-Do not rely only on frontend hiding.
-
-Do not return sensitive codes unnecessarily.
-
-Use 403 for authorization failures.
-
-Use 422 for validation failures.
-
-Use 409 for edit conflicts.
-
-Do not expose internal exception messages to users.
-
-Clamp or reject abusive limits consistently.
-
-Keep response shape stable unless the issue explicitly includes a breaking API change.
-
-## Frontend design principles
-
-Use existing route and query-key conventions.
-
-Use TanStack Query `enabled` rather than conditional hook calls.
-
-Do not let role-based early returns change hook order.
-
-Centralize repeated tag autocomplete logic when touching it.
-
-Use `encodeURIComponent` for tag names and wiki titles in URL path segments.
-
-Prefer graceful fallback for nullable actors:
-
-- bot operation
-- deleted user
-- migration-created data
-- external sync
-
-Do not assume all API user fields are non-null.
-
-## Testing priorities to add over time
-
-Frontend tests are especially important because the backend already has more mature RSpec coverage.
-
-Suggested first frontend tests:
-
-1. Tag autocomplete.
-2. Post form tag editing.
-3. Tag URL encoding.
-4. Wiki edit conflict UI.
-5. Role guard behavior.
-6. Null-user history rendering.
-7. Dialog behavior.
-8. Top navigation responsive behavior.
-
-Backend test priorities:
-
-1. BAN enforcement across public-looking endpoints.
-2. Material permissions.
-3. Preview SSRF rejection.
-4. System tag protection.
-5. Post optimistic locking.
-6. Wiki conflict detection.
-7. Tag alias/canonical behavior.
-8. Limit caps.
-9. Parent post parsing.
-10. Version recorder behavior.
-
-## What Codex should not do without explicit approval
-
-Do not:
-
-- Replace Rails.
-- Replace React.
-- Replace TanStack Query.
-- Redesign the database.
-- Rewrite Wiki storage.
-- Remove version tables.
-- Change authentication model.
-- Change role names.
-- Change tag category names.
-- Add background job infrastructure.
-- Add a new UI framework.
-- Add a new test framework if one already exists.
-- Add major dependencies.
-- Change public URL design.
-- Change production storage configuration.
-- Remove historical data behavior.
-- Simplify BAN/security checks.
-- Treat the site as private-only.
-
-## Good first Codex tasks
-
-Start with investigation-only tasks.
-
-Example:
-
-```txt
-Inspect the repository and summarize the Rails, React, TypeScript, and test setup.
-Do not modify files.
-List commands that actually exist in this repository.
-List risks Codex should know before editing.
-```
-
-Then small safe patches:
-
-```txt
-Fix a React Hooks rule violation in one file.
-Keep behavior unchanged.
-Run the relevant frontend verification commands.
-```
-
-```txt
-Add encodeURIComponent around one tag-name URL path segment.
-Add or update a test if the project has a frontend test setup.
-Run build/lint.
-```
-
-```txt
-Add a request spec for a known authorization rule.
-Do not change implementation unless the spec fails for the expected reason.
-```
-
-Avoid starting with:
-
-- Wiki history redesign.
-- Post versioning redesign.
-- Full admin screen suite.
-- Broad frontend refactor.
-- Database cleanup.
-- Authentication rewrite.
-
-## Relationship with ChatGPT
-
-ChatGPT has been used for:
-
-- Design review.
-- Risk analysis.
-- Prioritization.
-- Specification reconstruction.
-- Migration/locking discussions.
-- Codex migration planning.
-
-Codex should be used mainly for:
-
-- Repository inspection.
-- Localized implementation.
-- Test addition.
-- Running verification commands.
-- Producing small reviewable diffs.
-
-For ambiguous architecture, Codex should stop and present options rather than implement a guessed design.
-
-## Current strategic stance
-
-The project should not be rewritten from scratch.
-
-The current Rails + React system is acceptable.
-
-The immediate goal is not elegance.
-The immediate goal is safe public operation, data integrity, and maintainable incremental improvement.
-
-Priority is:
-
-1. Prevent abuse/security incidents.
-2. Preserve data correctness.
-3. Make editing safe for multiple users.
-4. Add tests around fragile frontend behavior.
-5. Improve admin/operation workflows.
-6. Optimize performance after obvious dangerous patterns are removed.
-
-## Final rule
-
-When current code, old specs, issue drafts, and memory disagree, current code wins.
-
-When current code is unsafe, write that explicitly and propose a small safe fix.
-
-When the task is too broad, split it.
-
-When verification cannot be performed, say exactly what was not verified.

docs/commands.md

@@ -1,30 +0,0 @@
-# Commands
-
-## Backend
-
-```sh
-cd backend
-bundle install
-bundle exec rails db:migrate
-bundle exec rspec
-bundle exec rails routes
-```
-
-## Frontend
-
-```sh
-cd frontend
-npm install
-npm run dev
-npm run build
-npm run lint
-npm run test
-npm run test:run
-```
-
-### Full verification
-
-```sh
-cd backend && bundle exec rspec
-cd ../frontend && npm run test:run && npm run build && npm run lint
-```

docs/issue-workflow.md

@@ -1,80 +0,0 @@
-# Issue workflow
-
-## Source of truth
-
-Gitea Issues are the source of truth for tasks, discussions, labels, milestones, and status.
-
-Do not copy the full backlog into git.
-
-Repository documents may define:
-
-- issue templates
-- triage rules
-- Codex task format
-- verification rules
-- release checklist
-
-## Labels
-
-Recommended labels:
-
-- `P0`
-- `P1`
-- `P2`
-- `P3`
-- `security`
-- `data-integrity`
-- `backend`
-- `frontend`
-- `wiki`
-- `tags`
-- `materials`
-- `theatre`
-- `codex-ready`
-- `needs-design`
-- `blocked`
-- `good-first-codex-task`
-
-## Codex-ready criteria
-
-An issue can be labeled `codex-ready` only when it has:
-
-- clear background
-- target area
-- concrete tasks
-- acceptance criteria
-- verification commands
-- explicit non-goals
-- no unresolved architecture decision
-
-## Workflow
-
-1. Create or refine the issue in Gitea.
-2. Add labels and milestone.
-3. If design is unclear, label `needs-design`.
-4. Discuss design before implementation.
-5. When scoped enough, label `codex-ready`.
-6. Give Codex the issue URL or copied issue body.
-7. Codex creates a branch.
-8. Codex implements a small patch.
-9. Codex runs verification commands.
-10. Human reviews the diff.
-11. Merge.
-12. Close the issue from the PR/commit message.
-
-## Commit message
-
-Use issue references when possible:
-
-```txt
-fix: prevent preview SSRF
-
-Refs: #123
-```
-or
-```
-fix: prevent preview SSRF
-
-Closes: #123
-```
-depending on whether the change fully resolves the issue.

docs/release-checklist.md

@@ -1,8 +0,0 @@
-# Release checklist
-
-- [ ] Backend specs pass
-- [ ] Frontend build passes
-- [ ] No pending migrations
-- [ ] Preview API SSRF checked
-- [ ] BAN behavior checked
-- [ ] CSP checked

docs/roadmap.md

@@ -1,8 +0,0 @@
-# Roadmap
-
-## Public announcement readiness
-
-- Harden preview API
-- Tighten material creation permission
-- Add admin MVP
-- Improve frontend tests

frontend/AGENTS.md

@@ -1,151 +0,0 @@
-# frontend/AGENTS.md
-
-## Scope
-
-These rules apply to work under `frontend/`.
-
-This is a Vite + React + TypeScript app using TanStack Query, Tailwind CSS,
-Framer Motion, Radix UI-style components, MDX, and Zustand.
-
-## Commands
-
-Use only scripts that exist in `package.json`:
-
-```sh
-npm run dev
-npm run build
-npm run lint
-npm run preview
-```
-
-`npm run build` runs `tsc -b && vite build`, and `postbuild` runs
-`node scripts/generate-sitemap.js`.
-
-There is currently no `test` script in `package.json`. Do not run or report
-`npm test` unless a test script is added.
-
-After frontend changes, run:
-
-```sh
-npm run build
-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`,
-  `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
-  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
-  `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`.
-- Encode URL path-segment values with `encodeURIComponent`.
-
-## TanStack Query
-
-- Use `@tanstack/react-query` for server state.
-- Query keys should come from `src/lib/queryKeys.ts`; add key builders there
-  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`.
-- 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
-  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
-  third-party request outside the Rails API.
-- For blob responses, pass `responseType: 'blob'` so the wrapper does not camelCase the body.
-
-## Imports and aliases
-
-- The `@` alias points to `frontend/src`.
-- Prefer `@/...` imports for app code instead of long relative paths.
-- Keep type imports separate with `import type`.
-- Match existing import grouping: external packages, app modules, then type imports.
-
-## Tailwind and UI
-
-- 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
-  `src/components/ui` before adding new primitives.
-- Keep Tailwind classes consistent with nearby components.
-- Prefer restrained, content-first UI chrome: avoid adding card backgrounds,
-  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`,
-  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
-  errors, not lint-only issues.
-
-## Files to avoid in routine work
-
-- Do not edit `dist/` output directly.
-- Do not inspect or modify `node_modules/` unless explicitly needed.
-- Keep generated build artifacts out of source changes unless the user asks for them.

frontend/eslint.config.js

@@ -5,7 +5,7 @@ import reactRefresh from 'eslint-plugin-react-refresh'
 import tseslint from 'typescript-eslint'
 
 export default tseslint.config(
-  { ignores: ['dist', 'tailwind.config.js'] },
+  { ignores: ['dist'] },
   {
     extends: [js.configs.recommended, ...tseslint.configs.recommended],
     files: ['**/*.{ts,tsx}'],

frontend/package.json

@@ -8,8 +8,6 @@
     "build": "tsc -b && vite build",
     "postbuild": "node scripts/generate-sitemap.js",
     "lint": "eslint .",
-    "test": "vitest",
-    "test:run": "vitest run",
     "preview": "vite preview"
   },
   "dependencies": {
@@ -47,10 +45,6 @@
   "devDependencies": {
     "@eslint/js": "^9.25.0",
     "@tailwindcss/typography": "^0.5.19",
-    "@testing-library/dom": "^10.4.1",
-    "@testing-library/jest-dom": "^6.9.1",
-    "@testing-library/react": "^16.3.2",
-    "@testing-library/user-event": "^14.6.1",
     "@types/axios": "^0.14.4",
     "@types/markdown-it": "^14.1.2",
     "@types/mdx": "^2.0.13",
@@ -64,13 +58,11 @@
     "eslint-plugin-react-hooks": "^5.2.0",
     "eslint-plugin-react-refresh": "^0.4.19",
     "globals": "^16.0.0",
-    "jsdom": "^26.1.0",
     "postcss": "^8.5.3",
     "tailwindcss": "^3.4.13",
     "typescript": "~5.8.3",
     "typescript-eslint": "^8.30.1",
-    "vite": "^6.3.5",
+    "vite": "^6.3.5"
-    "vitest": "^4.1.5"
   },
   "description": "This template provides a minimal setup to get React working in Vite with HMR and some ESLint rules.",
   "main": "eslint.config.js",

frontend/src/App.tsx

@@ -8,7 +8,6 @@ import { BrowserRouter,
 
 import RouteBlockerOverlay from '@/components/RouteBlockerOverlay'
 import TopNav from '@/components/TopNav'
-import DialogueProvider from '@/components/dialogues/DialogueProvider'
 import { Toaster } from '@/components/ui/toaster'
 import { apiPost, isApiError } from '@/lib/api'
 import DeerjikistDetailPage from '@/pages/deerjikists/DeerjikistDetailPage'
@@ -18,7 +17,6 @@ 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'
@@ -40,7 +38,7 @@ import WikiHistoryPage from '@/pages/wiki/WikiHistoryPage'
 import WikiNewPage from '@/pages/wiki/WikiNewPage'
 import WikiSearchPage from '@/pages/wiki/WikiSearchPage'
 
-import type { Dispatch, FC, ReactNode, SetStateAction } from 'react'
+import type { Dispatch, FC, SetStateAction } from 'react'
 
 import type { User } from '@/types'
 
@@ -63,9 +61,8 @@ 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/>}/>
@@ -81,10 +78,6 @@ 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={
-	      <AdminOnly user={user}>
-		<GekanatorPage/>
-	      </AdminOnly>}/>
 	  <Route path="/more" element={<MorePage/>}/>
 	  <Route path="*" element={<NotFound/>}/>
 	</Routes>
@@ -92,16 +85,6 @@ const RouteTransitionWrapper = ({ user, setUser }: {
 }
 
 
-const AdminOnly = ({ user, children }: {
-    user:      User | null
-    children:  ReactNode }) => {
-  if (user?.role !== 'admin')
-    return <NotFound/>
-
-  return <>{children}</>
-}
-
-
 const PostDetailRoute = ({ user }: { user: User | null }) => {
   const location = useLocation ()
   const key = location.pathname
@@ -109,7 +92,7 @@ const PostDetailRoute = ({ user }: { user: User | null }) => {
 }
 
 
-const App: FC = () => {
+export default (() => {
   const [user, setUser] = useState<User | null> (null)
   const [status, setStatus] = useState (200)
 
@@ -155,9 +138,7 @@ const App: FC = () => {
   return (
       <>
 	<RouteBlockerOverlay/>
-
 	<BrowserRouter>
-	  <DialogueProvider>
 	  <LayoutGroup>
 	    <motion.div
 		layout="position"
@@ -167,11 +148,7 @@ const App: FC = () => {
 	      <RouteTransitionWrapper user={user} setUser={setUser}/>
 	    </motion.div>
 	  </LayoutGroup>
-
 	  <Toaster/>
-	  </DialogueProvider>
 	</BrowserRouter>
       </>)
-}
+}) satisfies FC
-
-export default App

frontend/src/components/DraggableDroppableTagRow.tsx

@@ -19,7 +19,7 @@ type Props = {
     sp?:              boolean }
 
 
-const DraggableDroppableTagRow: FC<Props> = ({ tag, nestLevel, pathKey, parentTagId, suppressClickRef, sp }) => {
+export default (({ tag, nestLevel, pathKey, parentTagId, suppressClickRef, sp }: Props) => {
   const dndId = `tag-node:${ pathKey }`
 
   const downPosRef = useRef<{ x: number; y: number } | null> (null)
@@ -96,6 +96,4 @@ const DraggableDroppableTagRow: FC<Props> = ({ tag, nestLevel, pathKey, parentTa
 	  <TagLink tag={tag} nestLevel={nestLevel}/>
 	</motion.div>
       </div>)
-}
+}) satisfies FC<Props>
-
-export default DraggableDroppableTagRow

frontend/src/components/ErrorScreen.test.tsx

@@ -1,32 +0,0 @@
-import { render, screen } from '@testing-library/react'
-import { HelmetProvider } from 'react-helmet-async'
-import { describe, expect, it } from 'vitest'
-
-import ErrorScreen from '@/components/ErrorScreen'
-
-describe ('ErrorScreen', () => {
-  it.each ([
-    [403, '権限ないよ（笑）'],
-    [404, 'ページないよ（笑）'],
-    [500, '鯖でエラー出たって（嘲笑）'],
-    [503, '鯖死んでるよ（泣）'],
-  ]) ('renders status %s', (status, message) => {
-    render (
-        <HelmetProvider>
-          <ErrorScreen status={status}/>
-        </HelmetProvider>,
-    )
-
-    expect (screen.getByText (String (status))).toBeInTheDocument ()
-    expect (screen.getByText (message)).toBeInTheDocument ()
-    expect (screen.getByAltText ('逃げたギター')).toBeInTheDocument ()
-  })
-
-  it ('throws for unsupported statuses', () => {
-    expect (() => render (
-        <HelmetProvider>
-          <ErrorScreen status={418}/>
-        </HelmetProvider>,
-    )).toThrow ()
-  })
-})

frontend/src/components/ErrorScreen.tsx

@@ -10,7 +10,7 @@ import type { FC } from 'react'
 type Props = { status: number }
 
 
-const ErrorScreen: FC<Props> = ({ status }) => {
+export default (({ status }: Props) => {
   const [message, rightMsg, leftMsg]: [string, string, string] = (() => {
     switch (status)
     {
@@ -58,6 +58,4 @@ const ErrorScreen: FC<Props> = ({ status }) => {
 	  <p className="mr-[-.5em]">{message}</p>
 	</div>
       </MainArea>)
-}
+}) satisfies FC<Props>
-
-export default ErrorScreen

frontend/src/components/MaterialSidebar.tsx

@@ -31,7 +31,7 @@ const setChildrenById = (
     }))
 
 
-const MaterialSidebar: FC = () => {
+export default (() => {
   const [tags, setTags] = useState<TagWithDepth[]> ([])
   const [openTags, setOpenTags] = useState<Record<number, boolean>> ({ })
   const [tagFetchedFlags, setTagFetchedFlags] = useState<Record<number, boolean>> ({ })
@@ -94,6 +94,4 @@ const MaterialSidebar: FC = () => {
 	  {renderTags (tags)}
 	</ul>
       </SidebarComponent>)
-}
+}) satisfies FC
-
-export default MaterialSidebar

frontend/src/components/MenuSeparator.tsx

@@ -1,11 +1,9 @@
 import type { FC } from 'react'
 
 
-const MenuSeparator: FC = () => (
+export default (() => (
     <>
       <span className="hidden md:inline flex items-center px-2">|</span>
       <hr className="block md:hidden w-full opacity-25
 		     border-t border-black dark:border-white"/>
-    </>)
+    </>)) satisfies FC
-
-export default MenuSeparator

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

@@ -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']> ()
@@ -94,24 +79,6 @@ export default forwardRef ((props: Props, ref: ForwardedRef<NiconicoViewerHandle
   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 (() => {
@@ -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')
-	{
-	  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))
@@ -279,7 +234,6 @@ export default forwardRef ((props: Props, ref: ForwardedRef<NiconicoViewerHandle
 	  width={width}
 	  height={height}
 	  style={margedStyle}
-		  onLoad={startLoadCompleteTimer}
 	  allowFullScreen
 	  allow="autoplay"/>)
 })

frontend/src/components/PostEditForm.test.tsx

@@ -1,69 +0,0 @@
-import { fireEvent, render, screen, waitFor } from '@testing-library/react'
-import { describe, expect, it, vi } from 'vitest'
-
-import PostEditForm from '@/components/PostEditForm'
-import { buildPost, buildTag } from '@/test/factories'
-
-const postsApi = vi.hoisted (() => ({
-  updatePost: vi.fn (),
-}))
-
-const api = vi.hoisted (() => ({
-  isApiError: vi.fn (() => false),
-}))
-
-const toastApi = vi.hoisted (() => ({
-  toast: vi.fn (),
-}))
-
-vi.mock ('@/lib/posts', () => postsApi)
-vi.mock ('@/lib/api', () => api)
-vi.mock ('@/components/ui/use-toast', () => toastApi)
-vi.mock ('@/components/dialogues/DialogueProvider', () => ({
-  useDialogue: () => ({
-    choice: vi.fn (),
-  }),
-}))
-
-describe ('PostEditForm', () => {
-  it ('submits edited post fields with the current base version', async () => {
-    const onSave = vi.fn ()
-    const post = buildPost ({
-      id:        8,
-      versionNo: 4,
-      title:     'old',
-      tags:      [
-        buildTag ({ name: 'general-tag', category: 'general' }),
-        buildTag ({ id: 2, name: 'nico-tag', category: 'nico' }),
-      ],
-      parentPosts: [buildPost ({ id: 2, title: 'parent' })],
-    })
-    postsApi.updatePost.mockResolvedValueOnce ({
-      ...post,
-      versionNo: 5,
-      title:     'new',
-      tags:      [buildTag ({ name: 'new-tag' })],
-    })
-
-    render (<PostEditForm post={post} onSave={onSave}/>)
-
-    const [title, parentIds] = screen.getAllByRole ('textbox')
-    fireEvent.change (title, { target: { value: 'new' } })
-    fireEvent.change (parentIds, { target: { value: '3 4' } })
-    fireEvent.submit (screen.getByRole ('button', { name: '更新' }).closest ('form')!)
-
-    await waitFor (() => {
-      expect (postsApi.updatePost).toHaveBeenCalledWith (
-          expect.objectContaining ({
-            id:            8,
-            title:         'new',
-            parentPostIds: '3 4',
-            tags:          'general-tag',
-          }),
-          { baseVersionNo: 4 },
-      )
-    })
-    expect (onSave).toHaveBeenCalledWith (expect.objectContaining ({ versionNo: 5 }))
-    expect (toastApi.toast).toHaveBeenCalledWith ({ description: '更新しました．' })
-  })
-})

frontend/src/components/PostEditForm.tsx

@@ -2,23 +2,15 @@ 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 { apiPut } from '@/lib/api'
-import { updatePost } from '@/lib/posts'
-import { inputClass } from '@/lib/utils'
-import { useValidationErrors } from '@/lib/useValidationErrors'
 
-import type { FC, FormEvent } from 'react'
+import type { FC } from 'react'
 
 import type { Post, Tag } from '@/types'
 
-type PostFormField =
-    'parentPostIds' | 'tags' | 'originalCreatedAt'
-
 
 const tagsToStr = (tags: Tag[]): string => {
   const result: Tag[] = []
@@ -39,10 +31,7 @@ type Props = { post:    Post
 	       onSave:  (newPost: Post) => void }
 
 
-const PostEditForm: FC<Props> = ({ post, onSave }) => {
+export default (({ post, onSave }: Props) => {
-  const [disabled, setDisabled] = useState (false)
-  const { baseErrors, fieldErrors, clearValidationErrors, applyValidationError } =
-      useValidationErrors<PostFormField> ()
   const [originalCreatedBefore, setOriginalCreatedBefore] =
       useState<string | null> (post.originalCreatedBefore)
   const [originalCreatedFrom, setOriginalCreatedFrom] =
@@ -52,16 +41,16 @@ const PostEditForm: FC<Props> = ({ post, onSave }) => {
   const [tags, setTags] = useState<string> ('')
   const [title, setTitle] = useState (post.title)
 
-  const dialogue = useDialogue ()
+  const handleSubmit = async () => {
-
-  const update = async (...args: Parameters<typeof updatePost>) => {
-    clearValidationErrors ()
-
     try
     {
-      const data = await updatePost (...args)
+      const data = await apiPut<Post> (
+	  `/posts/${ post.id }`,
+	  { title, tags, parent_post_ids: parentPostIds,
+	    original_created_from: originalCreatedFrom,
+	    original_created_before: originalCreatedBefore },
+	  { headers: { 'Content-Type': 'multipart/form-data' } })
       onSave ({ ...post,
-		versionNo:              data.versionNo,
 		title:                  data.title,
 		tags:                   data.tags,
 		parentPosts:            data.parentPosts,
@@ -71,65 +60,9 @@ const PostEditForm: FC<Props> = ({ post, onSave }) => {
 		originalCreatedBefore:  data.originalCreatedBefore } as Post)
       toast ({ description: '更新しました．' })
     }
-    catch (e)
+    catch
-    {
-      const response = isApiError<{ mergeable?: boolean }> (e) ? e.response : undefined
-
-      if (response?.status !== 409)
-	{
-	  if (applyValidationError (e))
     {
       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
-	}
-
-      const action = await dialogue.choice ({
-	  title: '競合が発生しました．',
-	  description: (
-	      <div>
-		<p>ほかの耕作員が先に更新してゐます．</p>
-		<p>現在の変更をどう扱ひますか?</p>
-	      </div>),
-	  choices: [...(response?.data?.mergeable ? [{ value: 'merge', label: '差分をマージ' }] : []),
-		    { value: 'overwrite', label: '強制上書き', variant: 'danger' }] })
-
-      if (action === 'merge')
-	{
-	  // TODO: 差分 UI
-	  await update ({ id: post.id, title, tags, parentPostIds,
-			  originalCreatedFrom, originalCreatedBefore },
-			{ baseVersionNo: post.versionNo, merge: true })
-	  return
-	}
-
-      if (action === 'overwrite')
-	{
-	  await update ({ id: post.id, title, tags, parentPostIds,
-			  originalCreatedFrom, originalCreatedBefore },
-			{ baseVersionNo: post.versionNo, force: true })
-	  return
-	}
-    }
-  }
-
-  const handleSubmit = async (e: FormEvent) => {
-    e.preventDefault ()
-
-    setDisabled (true)
-    try
-    {
-      await update ({ id: post.id, title, tags, parentPostIds,
-		      originalCreatedFrom, originalCreatedBefore },
-		    { baseVersionNo: post.versionNo })
-    }
-    finally
-    {
-      setDisabled (false)
     }
   }
 
@@ -138,54 +71,40 @@ const PostEditForm: FC<Props> = ({ post, onSave }) => {
   }, [post])
 
   return (
-      <form onSubmit={handleSubmit} className="max-w-xl pt-2 space-y-4">
+      <div 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"
+		 className="w-full border rounded p-2"
-		  disabled={disabled}
-		  className={inputClass (invalid)}
 		 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
 	      type="text"
-		  disabled={disabled}
 	      value={parentPostIds}
 	      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
+	<PostFormTagsArea tags={tags} setTags={setTags}/>
-	    disabled={disabled}
-	    tags={tags}
-	    setTags={setTags}
-	    errors={fieldErrors.tags}/>
 
 	{/* オリジナルの作成日時 */}
 	<PostOriginalCreatedTimeField
-	    disabled={disabled}
 	    originalCreatedFrom={originalCreatedFrom}
 	    setOriginalCreatedFrom={setOriginalCreatedFrom}
 	    originalCreatedBefore={originalCreatedBefore}
-	    setOriginalCreatedBefore={setOriginalCreatedBefore}
+	    setOriginalCreatedBefore={setOriginalCreatedBefore}/>
-	    errors={fieldErrors.originalCreatedAt}/>
 
 	{/* 送信 */}
-	<Button type="submit" disabled={disabled}>
+	<Button onClick={handleSubmit}
+		className="px-4 py-2 bg-blue-600 text-white rounded disabled:bg-gray-400">
 	  更新
 	</Button>
-      </form>)
+      </div>)
-}
+}) satisfies FC<Props>
-
-export default PostEditForm

frontend/src/components/PostEmbed.test.tsx

@@ -1,128 +0,0 @@
-import { fireEvent, render, screen, waitFor } from '@testing-library/react'
-import { beforeEach, describe, expect, it, vi } from 'vitest'
-
-import PostEmbed from '@/components/PostEmbed'
-import { buildPost } from '@/test/factories'
-
-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 }) => {
-    nicoViewer.props (props)
-    return <div>Nico:{props.id}</div>
-  },
-}))
-
-vi.mock ('react-youtube', () => ({
-  default: ({ videoId }: { videoId: string }) => <div>YouTube:{videoId}</div>,
-}))
-
-describe ('PostEmbed', () => {
-  beforeEach (() => {
-    vi.clearAllMocks ()
-  })
-
-  it ('embeds nicovideo watch URLs', () => {
-    render (<PostEmbed post={buildPost ({ url: 'https://www.nicovideo.jp/watch/sm12345' })}/>)
-
-    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' })}/>)
-
-    expect (screen.getByRole ('link', { name: '@someone' })).toBeInTheDocument ()
-  })
-
-  it ('embeds youtube watch URLs', () => {
-    render (<PostEmbed post={buildPost ({ url: 'https://www.youtube.com/watch?v=abc123' })}/>)
-
-    expect (screen.getByText ('YouTube:abc123')).toBeInTheDocument ()
-  })
-
-  it ('asks before framing unknown external pages', async () => {
-    dialogue.confirm.mockResolvedValueOnce (true)
-    render (
-        <PostEmbed
-            post={buildPost ({ url: 'https://example.com/page', title: 'external' })}/>,
-    )
-
-    fireEvent.click (screen.getByRole ('link', { name: '外部ページを表示' }))
-
-    await waitFor (() => {
-      expect (dialogue.confirm).toHaveBeenCalled ()
-    })
-    expect (await screen.findByTitle ('external')).toHaveAttribute (
-        'src',
-        'https://example.com/page',
-    )
-  })
-})

frontend/src/components/PostEmbed.tsx

@@ -1,121 +1,21 @@
-import { useCallback, useEffect, useRef, useState } from 'react'
+import { useState } from 'react'
 import YoutubeEmbed from 'react-youtube'
 
 import NicoViewer from '@/components/NicoViewer'
 import TwitterEmbed from '@/components/TwitterEmbed'
-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> = ({
+export default (({ ref, post, onLoadComplete, onMetadataChange }: Props) => {
-    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)
 
   switch (url.hostname.split ('.').slice (-2).join ('.'))
@@ -134,15 +34,14 @@ const PostEmbed: FC<Props> = ({
 	      id={videoId}
 	      width={640}
 	      height={360}
-	      onLoadComplete={handleNiconicoLoadComplete}
+	      onLoadComplete={onLoadComplete}
-	      onMetadataChange={handleNiconicoMetadataChange}
+	      onMetadataChange={onMetadataChange}/>)
-	      onError={onError}/>)
     }
 
   case 'twitter.com':
   case 'x.com':
     {
-      const mUserId = url.pathname.match (/(?<=\/)[^/]+?(?=\/|$|\?)/)
+      const mUserId = url.pathname.match (/(?<=\/)[^\/]+?(?=\/|$|\?)/)
       const mStatusId = url.pathname.match (/(?<=\/status\/)\d+?(?=\/|$|\?)/)
       if (!(mUserId) || !(mStatusId))
 	break
@@ -166,13 +65,12 @@ const PostEmbed: FC<Props> = ({
 	      mute:         0,
 	      loop:         1,
 	      width:        '640',
-	      height:       '360' } }}
+	      height:       '360' } }}/>)
-	      onReady={handleYoutubeReady}
-	      onStateChange={handleYoutubeStateChange}
-	      onError={handleYoutubeError}/>)
     }
   }
 
+  const [framed, setFramed] = useState (false)
+
   return (
       <>
 	{framed
@@ -184,22 +82,15 @@ const PostEmbed: FC<Props> = ({
 		height={360}/>)
 	 : (
 	    <div>
-	      <a href="#" onClick={async e => {
+	      <a href="#" onClick={e => {
 		e.preventDefault ()
-
+		setFramed (confirm ('未確認の外部ページを表示します。\n'
-		setFramed (await dialogue.confirm ({
+				    + '悪意のあるスクリプトが実行される可能性があります。\n'
-		    title: '未確認の外部ページを表示します。',
+				    + '表示しますか?'))
-		    description: (
+		return
-			<div>
-			  <p>悪意のあるスクリプトが実行される可能性があります。</p>
-			  <p>表示しますか?</p>
-			</div>),
-		    confirmText: '表示' }))
 	      }}>
 		外部ページを表示
 	      </a>
 	    </div>)}
       </>)
-}
+}) satisfies FC<Props>
-
-export default PostEmbed