#90

AGENTS.md

@@ -12,21 +12,16 @@ BTRC Hub / タグ広場 is a split Rails API and React frontend repository.
 ## Stack
 
 - Backend: Ruby `3.2.2` from `backend/.ruby-version`, Rails `~> 8.0.2`.
-- Backend dependencies include `mysql2`, `sqlite3`, `rspec-rails`,
+- Backend dependencies include `mysql2`, `sqlite3`, `rspec-rails`, `factory_bot_rails`, `rack-cors`, `jwt`, `discard`, `gollum`, `whenever`, `aws-sdk-s3`, `brakeman`, and `rubocop-rails-omakase`.
-  `factory_bot_rails`, `rack-cors`, `jwt`, `discard`, `gollum`, `whenever`,
-  `aws-sdk-s3`, `brakeman`, and `rubocop-rails-omakase`.
 - Frontend: React `^19.1.0`, TypeScript `~5.8.3`, Vite `^6.3.5`.
-- Frontend data/UI dependencies include Axios, TanStack Query, Tailwind CSS,
+- Frontend data/UI dependencies include Axios, TanStack Query, Tailwind CSS, Framer Motion, Radix UI components, lucide-react, MDX/Markdown tooling, and Zustand.
-  Framer Motion, Radix UI components, lucide-react, MDX/Markdown tooling, and
-  Zustand.
 
 ## Main directories
 
 - `backend/app/controllers`: Rails API controllers.
 - `backend/app/models`: Active Record models.
 - `backend/app/representations`: API response representation classes.
-- `backend/app/services`: domain services such as version recording,
+- `backend/app/services`: domain services such as version recording, wiki commit, YouTube sync, and similarity calculation.
-  wiki commit, YouTube sync, and similarity calculation.
 - `backend/config/routes.rb`: API routes.
 - `backend/db/migrate`: migrations.
 - `backend/db/schema.rb`: current schema snapshot.
@@ -94,8 +89,7 @@ npm run test:run
 npm run preview
 ```
 
-`npm run build` runs `tsc -b && vite build`, then `postbuild` runs
+`npm run build` runs `tsc -b && vite build`, then `postbuild` runs `node scripts/generate-sitemap.js`.
-`node scripts/generate-sitemap.js`.
 
 `npm run test` runs Vitest in watch mode. Use `npm run test:run` for a non-watch frontend test run.
 
@@ -104,77 +98,40 @@ npm run preview
 - Prefer precise, minimal changes.
 - Do not flatter or over-explain.
 - Explain risks directly.
-- Prefer single quotes for strings unless interpolation or escaping makes
+- Prefer single quotes for strings unless interpolation or escaping makes double quotes better.
-  double quotes better.
 - Ruby: never put a space before method-call parentheses.
-- Ruby: never put a line break immediately before `)`.
 - Ruby: do not use `%w` or `%i`.
-- Ruby hashes are not blocks; keep `}` on the same line as the final pair.
+- TypeScript and Python: use GNU-style spacing before parentheses where syntactically valid.
-- Ruby hashes keep the first pair on the same line as `{` unless line length
-  requires a break.
-- Ruby blocks use separate `{ ... }` rules from hashes, with 2-space body
-  indentation.
-- For arrays, never put whitespace or a line break immediately before `]`.
-- Keep the first element on the same line as `[` by default.
-- If an array would exceed the line limit, break after `[` and indent
-  elements by 4 spaces.
-- TypeScript and Python: use GNU-style spacing before parentheses where
-  syntactically valid.
-- Never write Ruby, TypeScript, or TSX lines longer than 99 characters.
-- Aim to keep Ruby, TypeScript, and TSX lines within 79 characters where practical.
-- TypeScript and TSX use 4-space logical indentation.
-- In TypeScript and TSX only, replace every leading run of 8 spaces with a tab.
-- Tabs are only for leading indentation, never for spaces after non-space text.
 - Do not add production dependencies without explicit approval.
 
 ## Backend rules
 
-- Inspect existing routes, controllers, models, services, and specs before
+- Inspect existing routes, controllers, models, services, and specs before editing backend behavior.
-  editing backend behavior.
 - For API behavior changes, add or update request specs under `backend/spec/requests`.
-- Prefer RSpec for new backend tests; existing minitest files under
+- Prefer RSpec for new backend tests; existing minitest files under `backend/test` do not make minitest the default for new coverage.
-  `backend/test` do not make minitest the default for new coverage.
 - Do not weaken authentication, BAN user checks, or IP BAN checks.
-- Preserve the `X-Transfer-Code` user identification flow unless the task
+- Preserve the `X-Transfer-Code` user identification flow unless the task explicitly changes authentication.
-  explicitly changes authentication.
+- Be careful with version tables, `version_no`, optimistic concurrency, wiki revisions, and restore/diff behavior.
-- Be careful with version tables, `version_no`, optimistic concurrency,
-  wiki revisions, and restore/diff behavior.
 - Be careful with tag names, tag normalization, implications, similarities, and discard behavior.
-- Be sensitive to N+1 queries; avoid introducing them and proactively fix
-  existing N+1 issues in the code path being edited.
 - Keep migration files and `backend/db/schema.rb` consistent when changing schema.
 
 ## Frontend rules
 
 - Use `frontend/src/lib/api.ts` for API calls so headers and camelCase conversion stay consistent.
-- Add or reuse TanStack Query keys through `frontend/src/lib/queryKeys.ts`;
+- Add or reuse TanStack Query keys through `frontend/src/lib/queryKeys.ts`; avoid ad hoc query key arrays.
-  avoid ad hoc query key arrays.
 - Encode URL path-segment values with `encodeURIComponent`.
 - React hooks must be called unconditionally.
-- Keep page-level code under `frontend/src/pages` and shared UI/feature code
+- Keep page-level code under `frontend/src/pages` and shared UI/feature code under `frontend/src/components` unless existing patterns point elsewhere.
-  under `frontend/src/components` unless existing patterns point elsewhere.
 - Match existing Tailwind, component, and import alias conventions.
 
 ### Frontend TSX style
 
-- Preserve the local TSX formatting style.
+- Preserve the local TSX formatting style. Do not normalize TSX to common Prettier-style React formatting unless explicitly asked.
-- 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
+- Put two blank lines before and after top-level `const` function declarations, unless imports, exports, or file boundaries make that awkward.
-  declarations, unless imports, exports, or file boundaries make that awkward.
+- In TSX, indent nested tag attributes with one tab relative to the tag line. With the project tab width, this visually appears as 4 spaces.
-- In TSX, indent with 4-space logical indentation.
+- 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.
-- A leading tab is exactly equivalent to 8 leading spaces.
+- Keep JSX closing parentheses in the existing compact style, for example `</div>)` rather than moving `)` onto a separate line.
-- 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:
 
@@ -207,14 +164,10 @@ function PostFormTagsArea ({ tags, setTags }: Props) {
 
 - First inspect existing patterns; do not invent new architecture when a local convention exists.
 - Keep changes scoped to the requested issue.
-- Do not scan or summarize dependency/generated/runtime directories such as
+- Do not scan or summarize dependency/generated/runtime directories such as `node_modules`, `dist`, `tmp`, `log`, and `storage` unless explicitly needed.
-  `node_modules`, `dist`, `tmp`, `log`, and `storage` unless explicitly needed.
+- Before touching wiki, tag, versioning, BAN, IP BAN, or authentication behavior, inspect the related request specs and service objects.
-- Before touching wiki, tag, versioning, BAN, IP BAN, or authentication
+- If frontend code changes, run the existing frontend verification commands that apply: `npm run build`, `npm run lint`, and `npm run test:run`.
-  behavior, inspect the related request specs and service objects.
+- If backend code changes, run the relevant RSpec command; for broad backend changes, run `bundle exec rspec`.
-- If frontend code changes, run the existing frontend verification commands
-  that apply: `npm run build`, `npm run lint`, and `npm run test:run`.
-- If backend code changes, run the relevant RSpec command; for broad backend
-  changes, run `bundle exec rspec`.
 - If a verification command cannot be run or fails, report the exact command and failure.
 
 ## Completion criteria

backend/AGENTS.md

@@ -4,9 +4,7 @@
 
 These rules apply to work under `backend/`.
 
-This is a Rails API app using Active Record, RSpec, request specs,
+This is a Rails API app using Active Record, RSpec, request specs, service objects, representation classes, and version tables for post/tag/wiki history.
-service objects, representation classes, and version tables for post/tag/wiki
-history.
 
 ## Commands
 
@@ -52,57 +50,32 @@ If a command cannot be run or fails, report the exact command and failure.
 - `app/controllers`: API controllers.
 - `app/models`: Active Record models and concerns.
 - `app/representations`: JSON response shaping.
-- `app/services`: domain services such as version recorders, wiki commit,
+- `app/services`: domain services such as version recorders, wiki commit, YouTube sync, and similarity calculation.
-  YouTube sync, and similarity calculation.
 - `config/routes.rb`: public API routes.
 - `db/migrate`: migrations.
 - `db/schema.rb`: schema snapshot.
 - `lib/tasks`: custom Rake tasks.
 - `spec`: RSpec tests.
 
-Before changing behavior, inspect the matching route, controller, model,
+Before changing behavior, inspect the matching route, controller, model, service, representation, and spec.
-service, representation, and spec.
 
 ## Ruby style
 
 - Prefer precise, minimal changes.
 - Use single quotes unless interpolation or escaping makes double quotes better.
 - Do not put a space before Ruby method-call parentheses.
-- Never put a line break immediately before `)` in Ruby.
 - Do not use `%w` or `%i` in new Ruby code.
-- Never write a Ruby line longer than 99 characters.
-- Aim to keep Ruby lines within 79 characters where practical.
-- For small Ruby method definitions that take keyword arguments, match the
-  local no-parentheses style when nearby code uses it.
-- Treat Ruby hash `{ ... }` style and Ruby block `{ ... }` style as separate
-  rules.
-- Do not format Ruby hashes like Ruby blocks.
-- For Ruby hashes, keep the closing `}` on the same line as the final pair.
-- Keep the first pair on the same line as `{` by default.
-- If the hash would exceed the line limit, break after `{` and indent pairs
-  by 4 spaces.
-- Put one logical pair per line when the expression would otherwise become
-  dense.
-- For Ruby arrays, never put whitespace or a line break immediately before `]`.
-- Keep the first element on the same line as `[` by default.
-- If an array would exceed the line limit, break after `[` and indent
-  elements by 4 spaces.
-- For Ruby blocks, use 2-space indentation for the block body.
 - Keep comments short and useful; avoid narrating obvious code.
 - Do not add production dependencies without approval.
 
 ## Authentication and authorization
 
-- Authentication is handled through the `X-Transfer-Code` header in
+- Authentication is handled through the `X-Transfer-Code` header in `ApplicationController#authenticate_user`.
-  `ApplicationController#authenticate_user`.
 - `current_user` is set by looking up `User.inheritance_code`.
-- Do not bypass or weaken the `X-Transfer-Code` flow unless the task
+- Do not bypass or weaken the `X-Transfer-Code` flow unless the task explicitly changes authentication.
-  explicitly changes authentication.
+- Unauthenticated write actions should return `:unauthorized` consistently with existing controllers.
-- Unauthenticated write actions should return `:unauthorized` consistently
-  with existing controllers.
 - Role checks use `User` enum roles: `guest`, `member`, and `admin`.
-- Use `current_user.gte_member?` for member-or-admin write permissions where
+- Use `current_user.gte_member?` for member-or-admin write permissions where existing controllers do so.
-  existing controllers do so.
 - Use `current_user.admin?` only for admin-only paths, such as tag child relationship changes.
 - Do not replace role checks with looser presence checks.
 
@@ -115,8 +88,7 @@ service, representation, and spec.
 - User and IP bans use `banned_at`, not a boolean `banned` column.
 - `User#banned?` and `IpAddress#banned?` check `banned_at.present?`.
 - Do not weaken BAN or IP BAN behavior.
-- If changing request authentication or controller before actions, add or
+- If changing request authentication or controller before actions, add or update request specs covering banned users and banned IP addresses.
-  update request specs covering banned users and banned IP addresses.
 
 ## RSpec
 
@@ -127,86 +99,49 @@ service, representation, and spec.
 - Put Rake task coverage under `spec/tasks`.
 - `spec/rails_helper.rb` loads `spec/support/**/*.rb`.
 - Request specs include `AuthHelper` and `JsonHelper`.
-- `AuthHelper#sign_in_as(user)` stubs
+- `AuthHelper#sign_in_as(user)` stubs `ApplicationController#current_user`; use it when matching existing request spec style.
-  `ApplicationController#current_user`; use it when matching existing
+- Add or update request specs for API behavior changes, especially status codes, permissions, response shape, and version conflict behavior.
-  request spec style.
-- Add or update request specs for API behavior changes, especially status
-  codes, permissions, response shape, and version conflict behavior.
 
 ## Migrations
 
 - Keep migrations and `db/schema.rb` consistent.
 - Use reversible migrations where practical; otherwise define explicit `up` and `down`.
-- For data backfills inside migrations, follow the existing pattern of
+- For data backfills inside migrations, follow the existing pattern of defining migration-local `ActiveRecord::Base` classes with `self.table_name`.
-  defining migration-local `ActiveRecord::Base` classes with
-  `self.table_name`.
 - Preserve existing indexes, foreign keys, check constraints, and null constraints.
 - Be careful with MySQL-specific options already present in migrations, such as `after:`.
-- Do not edit old migrations just to change current behavior unless
+- Do not edit old migrations just to change current behavior unless explicitly requested; add a new migration.
-  explicitly requested; add a new migration.
 
 ## Version tables
 
 - Versioned records include posts, tags, nico tags, and wiki pages.
-- Current records have `version_no`; version tables have positive
+- Current records have `version_no`; version tables have positive `version_no` with unique indexes scoped to the parent record.
-  `version_no` with unique indexes scoped to the parent record.
 - Version event types are `create`, `update`, `discard`, and `restore`.
 - Version rows are readonly through the `VersionRecord` concern.
-- Use the existing recorder services instead of manually inserting version
+- Use the existing recorder services instead of manually inserting version rows in application code:
-  rows in application code:
   - `PostVersionRecorder`
   - `TagVersionRecorder`
   - `NicoTagVersionRecorder`
   - `WikiVersionRecorder`
   - `TagVersioning`
-- `VersionRecorder` locks the current record, validates sequence consistency,
+- `VersionRecorder` locks the current record, validates sequence consistency, skips unchanged update snapshots, creates the next version row, and updates the record `version_no`.
-  skips unchanged update snapshots, creates the next version row, and updates
-  the record `version_no`.
 - Do not update versioned records without considering whether a version snapshot must be created.
-- For optimistic concurrency paths, preserve `base_version_no`, `force`, and
+- For optimistic concurrency paths, preserve `base_version_no`, `force`, and `merge` semantics and cover conflicts in request specs.
-  `merge` semantics and cover conflicts in request specs.
 
 ## Domain cautions
 
-- Posts have tag snapshots, parent post implications, original-created ranges,
+- Posts have tag snapshots, parent post implications, original-created ranges, viewed state, and version conflict behavior.
-  viewed state, and version conflict behavior.
+- Tags have canonical names, aliases through `TagName`, categories, parent implications, discard behavior, and version snapshots.
-- Tags have canonical names, aliases through `TagName`, categories, parent
+- Nico tags have separate relation/version behavior; do not treat them like normal editable tags without checking existing code.
-  implications, discard behavior, and version snapshots.
+- Wiki pages involve page content, revisions/history, version rows, title/tag-name behavior, and diff/restore paths.
-- Nico tags have separate relation/version behavior; do not treat them like
+- Materials, theatres, and comments have user and permission checks; inspect the controller before changing them.
-  normal editable tags without checking existing code.
-- Wiki pages involve page content, revisions/history, version rows,
-  title/tag-name behavior, and diff/restore paths.
-- Materials, theatres, and comments have user and permission checks; inspect
-  the controller before changing them.
 
 ## API responses
 
 - Use representation classes under `app/representations` when existing endpoints do.
-- Keep response keys consistent with existing JSON contracts.
+- Keep response keys consistent with existing JSON contracts; frontend code expects camelCase conversion client-side, while Rails params and JSON keys are generally snake_case.
-- Frontend code expects camelCase conversion client-side, while Rails params
+- Preserve existing HTTP status conventions: `:unauthorized` for no user, `:forbidden` for insufficient role or banned user, `:not_found` for missing records, and `:unprocessable_entity` for validation failures.
-  and JSON keys are generally snake_case.
-- Preserve existing HTTP status conventions:
-  `:unauthorized` for no user, `:forbidden` for insufficient role or banned
-  user, `:not_found` for missing records, and `:unprocessable_entity` for
-  validation failures.
-- For diagnostic or internal helper JSON, prefer a deliberately light response
-  shape over full representation classes when callers only need identifiers,
-  labels, URLs, or weights.
-
-## Active Record performance
-
-- When a controller action serializes nested associations, preload the
-  associations it will touch instead of allowing N+1 queries.
-- Be sensitive to N+1 queries in all backend work.
-- Avoid introducing N+1 queries, and proactively fix existing N+1 issues when
-  you find them in the code path you are editing.
-- When an association may already be preloaded, prefer loaded-association
-  checks that reuse the preloaded data without losing the efficient database
-  path.
 
 ## Files to avoid in routine work
 
-- Do not inspect or edit `tmp/`, `log/`, `storage/`, `vendor/`, or dependency
+- Do not inspect or edit `tmp/`, `log/`, `storage/`, `vendor/`, or dependency directories unless explicitly needed.
-  directories unless explicitly needed.
+- Do not modify generated schema or migration output without the corresponding migration when schema changes are made.
-- Do not modify generated schema or migration output without the corresponding
-  migration when schema changes are made.

backend/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(:uploaded_user, tags: [:deerjikists, :materials, { tag_name: :wiki_page }])
-                 tags: [:deerjikists, :materials, { tag_name: :wiki_page }])
         .with_attached_thumbnail
 
     q = q.where('posts.url LIKE ?', "%#{ url }%") if url
@@ -96,7 +95,7 @@ class PostsController < ApplicationController
   end
 
   def random
-    post = filtered_posts.preload(:uploaded_user, :parents, :children,
+    post = filtered_posts.preload(:uploaded_user,
                                   tags: [:deerjikists, :materials, { tag_name: :wiki_page }])
                          .with_attached_thumbnail
                          .order('RAND()')
@@ -109,8 +108,7 @@ class PostsController < ApplicationController
   def show
     post =
         Post
-        .includes(:uploaded_user, :parents, :children,
+        .includes(:uploaded_user, tags: [:deerjikists, :materials, { tag_name: :wiki_page }])
-                  tags: [:deerjikists, :materials, { tag_name: :wiki_page }])
         .with_attached_thumbnail
         .find_by(id: params[:id])
     return head :not_found unless post

backend/app/controllers/theatre_comments_controller.rb

@@ -1,21 +1,14 @@
 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
@@ -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/models/tag.rb

@@ -81,7 +81,7 @@ class Tag < ApplicationRecord
 
   def material_id = materials.first&.id
 
-  def has_deerjikists = deerjikists.loaded? ? deerjikists.any? : deerjikists.exists?
+  def has_deerjikists = deerjikists.present?
 
   def self.tagme = find_or_create_by_tag_name!('タグ希望', category: :meta)
   def self.bot = find_or_create_by_tag_name!('bot操作', category: :meta)

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/services/theatre_post_advancer.rb

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

backend/app/services/theatre_post_selector.rb

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

backend/app/services/theatre_skip_finalizer.rb

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

backend/config/routes.rb

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

backend/db/migrate/20260514221900_create_theatre_programmes.rb

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

backend/db/migrate/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/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_06_000000) do
+ActiveRecord::Schema[8.0].define(version: 2026_05_07_213300) 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
@@ -283,55 +283,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_06_06_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
@@ -513,18 +464,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_06_06_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/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

frontend/AGENTS.md

@@ -4,8 +4,7 @@
 
 These rules apply to work under `frontend/`.
 
-This is a Vite + React + TypeScript app using TanStack Query, Tailwind CSS,
+This is a Vite + React + TypeScript app using TanStack Query, Tailwind CSS, Framer Motion, Radix UI-style components, MDX, and Zustand.
-Framer Motion, Radix UI-style components, MDX, and Zustand.
 
 ## Commands
 
@@ -18,11 +17,9 @@ npm run lint
 npm run preview
 ```
 
-`npm run build` runs `tsc -b && vite build`, and `postbuild` runs
+`npm run build` runs `tsc -b && vite build`, and `postbuild` runs `node scripts/generate-sitemap.js`.
-`node scripts/generate-sitemap.js`.
 
-There is currently no `test` script in `package.json`. Do not run or report
+There is currently no `test` script in `package.json`. Do not run or report `npm test` unless a test script is added.
-`npm test` unless a test script is added.
 
 After frontend changes, run:
 
@@ -35,37 +32,18 @@ If either command cannot be run or fails, report the exact command and failure.
 
 ## TypeScript
 
-- TypeScript is strict. `tsconfig.app.json` enables `strict`,
+- TypeScript is strict. `tsconfig.app.json` enables `strict`, `noUnusedLocals`, `noUnusedParameters`, `erasableSyntaxOnly`, `noFallthroughCasesInSwitch`, and `noUncheckedSideEffectImports`.
-  `noUnusedLocals`, `noUnusedParameters`, `erasableSyntaxOnly`,
-  `noFallthroughCasesInSwitch`, and `noUncheckedSideEffectImports`.
 - Keep types explicit at module boundaries, API helpers, and exported utilities.
 - Use `import type` for type-only imports.
 - Prefer existing shared types from `src/types.ts` before adding local duplicate types.
-- Preserve the repository's existing spacing style in TypeScript, including
+- Preserve the repository's existing spacing style in TypeScript, including GNU-style spacing before call parentheses where it is already used.
-  GNU-style spacing before call parentheses where it is already used.
 - Prefer single quotes for strings unless interpolation or escaping makes double quotes better.
-- Never write a TypeScript or TSX line longer than 99 characters.
-- Aim to keep TypeScript and TSX lines within 79 characters where practical.
-- Use 4-space logical indentation in TypeScript and TSX.
-- For arrays, never put whitespace or a line break immediately before `]`.
-- Keep the first element on the same line as `[` by default.
-- If an array would exceed the line limit, break after `[` and indent
-  elements by 4 spaces.
-- In TypeScript and TSX only, replace every leading run of 8 spaces with a tab
-  to reduce bytes.
-- Treat one leading tab as exactly equivalent to 8 leading spaces.
-- Use tabs only for leading indentation. Never replace spaces that occur after
-  a non-space character on the same line.
 
 ## React
 
 - Use function components.
-- Existing page components commonly export an anonymous function satisfying
+- Existing page components commonly export an anonymous function satisfying `FC`; match nearby file style when editing.
-  `FC`; match nearby file style when editing.
 - React hooks must be called unconditionally and at the top level of components or custom hooks.
-- Gate editing and other privileged controls with shared permission helpers
-  such as `canEditContent`, instead of showing controls and relying only on a
-  later API failure.
 - Keep page-level components under `src/pages`.
 - Keep shared and feature components under `src/components`.
 - Use `react-router-dom` route params and navigation patterns already present in `src/App.tsx`.
@@ -74,23 +52,17 @@ If either command cannot be run or fails, report the exact command and failure.
 ## TanStack Query
 
 - Use `@tanstack/react-query` for server state.
-- Query keys should come from `src/lib/queryKeys.ts`; add key builders there
+- Query keys should come from `src/lib/queryKeys.ts`; add key builders there instead of using ad hoc arrays in components.
-  instead of using ad hoc arrays in components.
+- Fetch functions should live in domain helpers under `src/lib`, such as `posts.ts`, `tags.ts`, or `wiki.ts`.
-- Fetch functions should live in domain helpers under `src/lib`, such as
+- Use `useQueryClient().invalidateQueries` with the shared root keys when mutations affect cached lists or detail views.
-  `posts.ts`, `tags.ts`, or `wiki.ts`.
+- The app-wide `QueryClient` is configured in `src/main.tsx`; do not create additional clients in feature code.
-- Use `useQueryClient().invalidateQueries` with the shared root keys when
-  mutations affect cached lists or detail views.
-- The app-wide `QueryClient` is configured in `src/main.tsx`; do not create
-  additional clients in feature code.
 
 ## API calls
 
 - Use `src/lib/api.ts` for HTTP calls.
-- The API wrapper attaches `X-Transfer-Code` from `localStorage` and converts
+- The API wrapper attaches `X-Transfer-Code` from `localStorage` and converts non-blob responses to camelCase.
-  non-blob responses to camelCase.
 - Send Rails snake_case params and request body keys where the backend expects them.
-- Do not bypass the API wrapper unless there is a specific reason, such as a
+- Do not bypass the API wrapper unless there is a specific reason, such as a third-party request outside the Rails API.
-  third-party request outside the Rails API.
 - For blob responses, pass `responseType: 'blob'` so the wrapper does not camelCase the body.
 
 ## Imports and aliases
@@ -104,41 +76,17 @@ If either command cannot be run or fails, report the exact command and failure.
 
 - Tailwind scans `src/**/*.{html,js,ts,jsx,tsx,mdx}`.
 - Use `cn` from `src/lib/utils.ts` for conditional class names and class merging.
-- Reuse components from `src/components/common`, `src/components/layout`, and
+- Reuse components from `src/components/common`, `src/components/layout`, and `src/components/ui` before adding new primitives.
-  `src/components/ui` before adding new primitives.
 - Keep Tailwind classes consistent with nearby components.
-- Prefer restrained, content-first UI chrome: avoid adding card backgrounds,
+- When adding dynamic tag color classes, update `tailwind.config.js` safelist if the class cannot be statically detected.
-  heavy borders, or nested panel decoration unless the surrounding screen
-  already uses them.
-- Keep operational screens dense and direct; trim explanatory copy and use
-  short Japanese labels that fit the control.
-- Preserve existing Japanese tone and orthography in nearby UI text, including
-  old-kana wording where the file already uses it.
-- When adding dynamic tag color classes, update `tailwind.config.js` safelist
-  if the class cannot be statically detected.
 - Do not introduce new UI libraries or production dependencies without approval.
 
-## TSX formatting
-
-- Preserve compact TSX expression shapes such as inline ternary branches and
-  closing `</div>)` forms when nearby code uses them.
-- For long Tailwind `className` strings, wrap across lines only when needed.
-- Keep continuation indentation aligned with the 4-space logical indentation
-  rule, using tabs only as leading 8-space compression.
-- Do not add braces around `if`, `else`, or `for` bodies when the body is a
-  single physical line.
-- Always add braces around `if`, `else`, or `for` bodies when the body spans
-  two or more physical lines, even if it is one statement.
-- Avoid reformatting unrelated JSX.
-
 ## Lint and build constraints
 
-- ESLint uses `@eslint/js`, `typescript-eslint`, `eslint-plugin-react-hooks`,
+- ESLint uses `@eslint/js`, `typescript-eslint`, `eslint-plugin-react-hooks`, and `eslint-plugin-react-refresh`.
-  and `eslint-plugin-react-refresh`.
 - The hooks rules are enforced; fix hook ordering instead of disabling the rule.
 - `react-refresh/only-export-components` is enabled as a warning with `allowConstantExport`.
-- Build failures from unused locals or unused parameters are TypeScript
+- Build failures from unused locals or unused parameters are TypeScript errors, not lint-only issues.
-  errors, not lint-only issues.
 
 ## Files to avoid in routine work
 

frontend/src/App.tsx

@@ -64,7 +64,7 @@ const RouteTransitionWrapper = ({ user, setUser }: {
 	  <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/>}/>

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/PostEmbed.test.tsx

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

frontend/src/components/PostEmbed.tsx

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

frontend/src/components/TopNav.tsx

@@ -55,6 +55,12 @@ export const menuOutline = ({ tag, wikiId, user, pathName }: {
 	  { name: '追加', to: '/materials/new' },
 	  { name: '全体履歴', to: '/materials/changes', visible: false },
 	  { name: 'ヘルプ', to: '/wiki/ヘルプ:素材集' }] },
+      { name: '上映会', to: '/theatres/1', base: '/theatres', subMenu: [
+	  { name: <>第&thinsp;1&thinsp;会場</>, to: '/theatres/1' },
+	  { name: 'CyTube', to: '//cytube.mm428.net/r/deernijika' },
+	  { name: <>ニジカ放送局第&thinsp;1&thinsp;チャンネル</>,
+	    to: '//www.youtube.com/watch?v=DCU3hL4Uu6A' },
+	  { name: 'ヘルプ', to: '/wiki/ヘルプ:上映会' }] },
       { name: 'Wiki', to: '/wiki/ヘルプ:ホーム', base: '/wiki', subMenu: [
 	  { name: '検索', to: '/wiki' },
 	  { name: '新規', to: '/wiki/new' },
@@ -65,8 +71,6 @@ export const menuOutline = ({ tag, wikiId, user, pathName }: {
 	    visible: wikiPageFlg },
 	  { name: '履歴', to: `/wiki/changes?id=${ wikiId }`, visible: wikiPageFlg },
 	  { name: '編輯', to: `/wiki/${ wikiId || wikiTitle }/edit`, visible: wikiPageFlg }] },
-      { name: 'おたのしみ', visible: false, subMenu: [
-	  { name: '上映会 (β)', to: '/theatres/1' }] },
       { name: 'ユーザ', to: '/users/settings', visible: false, subMenu: [
 	  { name: '一覧', to: '/users', visible: false },
 	  { name: 'お前', to: `/users/${ user?.id }`, visible: false },
@@ -128,12 +132,8 @@ const TopNav: FC<Props> = ({ user }) => {
 
   const menu = menuOutline ({ tag, wikiId, user, pathName: location.pathname })
   const visibleMenu = menu.filter ((item): item is MenuVisibleItem => item.visible ?? true)
-  const moreMenu = menu.filter (item =>
-      !(item.visible ?? true)
-      || item.subMenu.filter (subItem => subItem.visible ?? true).length > 0)
   const activeIdx =
       visibleMenu.findIndex (item => location.pathname.startsWith (item.base || item.to))
-  const submenuHeight = moreVsbl ? 40 * moreMenu.length : (activeIdx < 0 ? 0 : 40)
 
   const prevActiveIdxRef = useRef<number> (activeIdx)
 
@@ -244,9 +244,9 @@ const TopNav: FC<Props> = ({ user }) => {
 	  <motion.div
 	      key="submenu-shell"
 	      layout
-	      className="relative z-20 hidden md:block overflow-hidden
+	      className="relative hidden md:block overflow-hidden
 			 bg-yellow-200 dark:bg-red-950"
-	      animate={{ height: submenuHeight }}
+	      style={{ height: moreVsbl ? 40 * menu.length : (activeIdx < 0 ? 0 : 40) }}
 	      onMouseLeave={() => {
 		if (moreVsbl)
 		  setMoreVsbl (false)
@@ -257,7 +257,7 @@ const TopNav: FC<Props> = ({ user }) => {
 	      }}>
 	  {moreVsbl
 	   ? (
-	      moreMenu.map ((item, i) => (
+	      menu.map ((item, i) => (
 		  <div key={i} className="relative h-[40px]">
 		    <div className="absolute inset-0 flex items-center px-3">
 		      <motion.div
@@ -267,7 +267,7 @@ const TopNav: FC<Props> = ({ user }) => {
 			       : { initial: { x: 40, y: -40, opacity: 0 },
 				   animate: { x: 0, y: 0, opacity: 1 },
 				   exit: { x: 40, y: -40, opacity: 0 } })}
-			  className="z-10 h-full flex items-center px-3 font-bold w-28">
+			  className="z-10 h-full flex items-center px-3 font-bold w-24">
 			<h2>{item.name}</h2>
 		      </motion.div>
 		      {item.subMenu

frontend/src/lib/api.ts

@@ -64,14 +64,11 @@ export const apiPatch = async <T> (
 ): Promise<T> => apiP ('patch', path, body, opt)
 
 
-export const apiDelete = async <T = void> (
+export const apiDelete = async (
     path: string,
     opt?: Opt,
-): Promise<T> => {
+): Promise<void> => {
-  const res = await client.delete (path, withUserCode (opt))
+  await client.delete (path, withUserCode (opt))
-  if (res.data == null || res.data === '')
-    return undefined as T
-  return toCamel (res.data as Record<string, unknown>, { deep: true }) as T
 }
 
 

frontend/src/lib/users.ts

@@ -2,7 +2,6 @@ import type { User, UserRole } from '@/types'
 
 const CONTENT_EDITOR_ROLES: readonly UserRole[] = ['admin', 'member']
 
-
 export const canEditContent = (
     user: Pick<User, 'role'> | null | undefined,
 ): boolean => user != null && CONTENT_EDITOR_ROLES.includes (user.role)

frontend/src/pages/theatres/TheatreDetailPage.test.tsx

@@ -1,298 +0,0 @@
-import { act, fireEvent, screen, waitFor } from '@testing-library/react'
-import { Route, Routes } from 'react-router-dom'
-import { beforeEach, describe, expect, it, vi } from 'vitest'
-
-import TheatreDetailPage from '@/pages/theatres/TheatreDetailPage'
-import { buildPost,
-	 buildTheatre,
-	 buildTheatreComment,
-	 buildTheatreInfo,
-	 buildTheatrePostSelectionWeights,
-	 buildTheatreProgramme,
-	 buildUser } from '@/test/factories'
-import { renderWithProviders } from '@/test/render'
-
-import type { ReactNode } from 'react'
-
-const api = vi.hoisted (() => ({
-  apiDelete:  vi.fn (),
-  apiGet:     vi.fn (),
-  apiPatch:   vi.fn (),
-  apiPost:    vi.fn (),
-  apiPut:     vi.fn (),
-  isApiError: vi.fn (() => false),
-}))
-
-const postsApi = vi.hoisted (() => ({
-  fetchPost: vi.fn (),
-}))
-
-const dialogue = vi.hoisted (() => ({
-  confirm: vi.fn (),
-}))
-
-const postEmbed = vi.hoisted (() => ({
-  props: vi.fn (),
-  play:  vi.fn (),
-  seek:  vi.fn (),
-}))
-
-vi.mock ('@/lib/api', () => api)
-vi.mock ('@/lib/posts', () => postsApi)
-vi.mock ('@/components/dialogues/DialogueProvider', () => ({
-  useDialogue: () => dialogue,
-}))
-vi.mock ('@/components/PostEmbed', () => ({
-  default: (props: {
-    ref?: { current: unknown }
-    post: { title: string | null; url: string }
-  }) => {
-    postEmbed.props (props)
-    if (props.ref)
-      props.ref.current = {
-        play: postEmbed.play,
-        seek: postEmbed.seek,
-      }
-
-    return <div>Embed:{props.post.title || props.post.url}</div>
-  },
-}))
-vi.mock ('@/components/PostEditForm', () => ({
-  default: () => <div>Post edit form</div>,
-}))
-vi.mock ('framer-motion', () => ({
-  motion: {
-    aside: ({ children }: { children?: ReactNode }) => <aside>{children}</aside>,
-    div:   ({ children }: { children?: ReactNode }) => <div>{children}</div>,
-    main:  ({ children }: { children?: ReactNode }) => <main>{children}</main>,
-  },
-}))
-
-const currentPost = buildPost ({
-  id:    10,
-  title: '上映中の投稿',
-  url:   'https://www.nicovideo.jp/watch/sm10',
-})
-const theatre = buildTheatre ({ id: 7, name: '上映室' })
-const programme = buildTheatreProgramme ({
-  theatreId: 7,
-  position:  3,
-  post:      currentPost,
-})
-const weights = buildTheatrePostSelectionWeights ({
-  lightestPosts: [{
-    post:    currentPost,
-    penalty: 2,
-    weight:  0.5,
-    tags:    [],
-  }],
-})
-
-const renderPage = (user = buildUser ({ id: 1, role: 'member' })) =>
-  renderWithProviders (
-      <Routes>
-        <Route path="/theatres/:id" element={<TheatreDetailPage user={user}/>}/>
-      </Routes>,
-      { route: '/theatres/7' },
-  )
-
-const mockDefaultApi = () => {
-  api.apiGet.mockImplementation ((path: string) => {
-    switch (path)
-    {
-    case '/theatres/7':
-      return Promise.resolve (theatre)
-
-    case '/theatres/7/comments':
-      return Promise.resolve ([
-        buildTheatreComment ({
-          theatreId: 7,
-          no:        2,
-          user:      { id: 1, name: 'tester' },
-          content:   '視聴コメント',
-        }),
-      ])
-
-    case '/theatres/7/programmes':
-      return Promise.resolve ([programme])
-
-    case '/theatres/7/post_selection_weights':
-      return Promise.resolve (weights)
-
-    default:
-      return Promise.reject (new Error (`Unexpected GET ${ path }`))
-    }
-  })
-
-  api.apiPut.mockImplementation ((path: string) => {
-    switch (path)
-    {
-    case '/theatres/7/watching':
-      return Promise.resolve (buildTheatreInfo ({
-        postId:        currentPost.id,
-        postStartedAt: '2026-01-02T03:04:05.000Z',
-        postElapsedMs: 1_000,
-        watchingUsers: [{ id: 1, name: 'tester' }],
-        skipVote:      {
-          votesCount:         0,
-          requiredCount:      2,
-          watchingUsersCount: 1,
-          voted:              false,
-        },
-      }))
-
-    case '/theatres/7/skip_vote':
-      return Promise.resolve (buildTheatreInfo ({
-        postId:        currentPost.id,
-        postStartedAt: '2026-01-02T03:04:05.000Z',
-        postElapsedMs: 2_000,
-        watchingUsers: [{ id: 1, name: 'tester' }],
-        skipVote:      {
-          votesCount:         1,
-          requiredCount:      2,
-          watchingUsersCount: 1,
-          voted:              true,
-        },
-      }))
-
-    default:
-      return Promise.reject (new Error (`Unexpected PUT ${ path }`))
-    }
-  })
-
-  api.apiDelete.mockResolvedValue (undefined)
-  api.apiPatch.mockResolvedValue (undefined)
-  api.apiPost.mockResolvedValue (undefined)
-  postsApi.fetchPost.mockResolvedValue (currentPost)
-  dialogue.confirm.mockResolvedValue (true)
-}
-
-describe ('TheatreDetailPage', () => {
-  beforeEach (() => {
-    vi.useRealTimers ()
-    vi.clearAllMocks ()
-    mockDefaultApi ()
-  })
-
-  it ('loads theatre state, comments, current post, programme history, and weights', async () => {
-    renderPage ()
-
-    expect (await screen.findByText ('上映会場『上映室』')).toBeInTheDocument ()
-    expect (await screen.findByText ('Embed:上映中の投稿')).toBeInTheDocument ()
-    expect (screen.getAllByText ('視聴コメント')[0]).toBeInTheDocument ()
-    expect (screen.getAllByText ('上映中の投稿')[0]).toBeInTheDocument ()
-    expect (screen.getByText ('penalty 2')).toBeInTheDocument ()
-
-    await waitFor (() => {
-      expect (postsApi.fetchPost).toHaveBeenCalledWith ('10')
-    })
-  })
-
-  it ('votes to skip the current post', async () => {
-    renderPage ()
-
-    await screen.findByText ('Embed:上映中の投稿')
-
-    fireEvent.click (screen.getByRole ('button', { name: 'スキップ 0 / 2' }))
-
-    await waitFor (() => {
-      expect (api.apiPut).toHaveBeenCalledWith (
-          '/theatres/7/skip_vote',
-          { post_id: 10 },
-      )
-    })
-    expect (await screen.findByRole ('button', { name: 'スキップ取消 1 / 2' }))
-      .toBeInTheDocument ()
-  })
-
-  it ('does not seek to zero while applying video length from the player', async () => {
-    api.apiPut.mockImplementation ((path: string) => {
-      switch (path)
-      {
-      case '/theatres/7/watching':
-        return Promise.resolve (buildTheatreInfo ({
-          hostFlg:       true,
-          postId:        currentPost.id,
-          postStartedAt: '2026-01-02T03:04:05.000Z',
-          postElapsedMs: 7_000,
-          watchingUsers: [{ id: 1, name: 'tester' }],
-          skipVote:      {
-            votesCount:         0,
-            requiredCount:      2,
-            watchingUsersCount: 1,
-            voted:              false,
-          },
-        }))
-
-      default:
-        return Promise.reject (new Error (`Unexpected PUT ${ path }`))
-      }
-    })
-
-    renderPage ()
-    await screen.findByText ('Embed:上映中の投稿')
-
-    const props = postEmbed.props.mock.calls.at (-1)![0]
-
-    act (() => {
-      props.onVideoReady (120_000)
-      props.onPlaybackChange (0)
-    })
-
-    const seekMs = postEmbed.seek.mock.calls[0][0]
-    expect (seekMs).toBeGreaterThanOrEqual (7_000)
-    expect (seekMs).toBeLessThan (10_000)
-    expect (postEmbed.seek).not.toHaveBeenCalledWith (0)
-  })
-
-  it ('does not advance host post while video length is unknown', async () => {
-    api.apiPut.mockImplementation ((path: string) => {
-      switch (path)
-      {
-      case '/theatres/7/watching':
-        return Promise.resolve (buildTheatreInfo ({
-          hostFlg:       true,
-          postId:        currentPost.id,
-          postStartedAt: '2026-01-02T03:04:05.000Z',
-          postElapsedMs: 4_000,
-          watchingUsers: [{ id: 1, name: 'tester' }],
-          skipVote:      {
-            votesCount:         0,
-            requiredCount:      2,
-            watchingUsersCount: 1,
-            voted:              false,
-          },
-        }))
-
-      default:
-        return Promise.reject (new Error (`Unexpected PUT ${ path }`))
-      }
-    })
-
-    renderPage ()
-
-    await screen.findByText ('Embed:上映中の投稿')
-    await waitFor (() => {
-      expect (api.apiPut).toHaveBeenCalledWith ('/theatres/7/watching')
-    })
-
-    await waitFor (() => {
-      expect (api.apiPut).toHaveBeenCalledTimes (2)
-    }, { timeout: 2_500 })
-    expect (api.apiPatch).not.toHaveBeenCalledWith ('/theatres/7/next_post')
-  })
-
-  it ('deletes an owned comment after confirmation', async () => {
-    renderPage ()
-
-    fireEvent.click ((await screen.findAllByLabelText ('コメントを削除'))[0])
-
-    await waitFor (() => {
-      expect (dialogue.confirm).toHaveBeenCalled ()
-    })
-    await waitFor (() => {
-      expect (api.apiDelete).toHaveBeenCalledWith ('/theatres/7/comments/2')
-    })
-    expect (await screen.findAllByText ('削除されました．')).toHaveLength (2)
-  })
-})

frontend/src/pages/theatres/TheatreDetailPage.tsx

@@ -1,271 +1,65 @@
-import { motion } from 'framer-motion'
+import { useEffect, useRef, useState } from 'react'
-import { useCallback, useEffect, useMemo, useRef, useState } from 'react'
 import { Helmet } from 'react-helmet-async'
 import { useParams } from 'react-router-dom'
 
 import ErrorScreen from '@/components/ErrorScreen'
-import PostEditForm from '@/components/PostEditForm'
 import PostEmbed from '@/components/PostEmbed'
 import PrefetchLink from '@/components/PrefetchLink'
-import TagLink from '@/components/TagLink'
+import TagDetailSidebar from '@/components/TagDetailSidebar'
 import FieldError from '@/components/common/FieldError'
-import { useDialogue } from '@/components/dialogues/DialogueProvider'
+import MainArea from '@/components/layout/MainArea'
-import { Button } from '@/components/ui/button'
+import SidebarComponent from '@/components/layout/SidebarComponent'
 import { SITE_TITLE } from '@/config'
-import { CATEGORIES, CATEGORY_NAMES } from '@/consts'
+import { apiGet, apiPatch, apiPost, apiPut, isApiError } from '@/lib/api'
-import { apiDelete, apiGet, apiPatch, apiPost, apiPut, isApiError } from '@/lib/api'
 import { fetchPost } from '@/lib/posts'
-import { canEditContent } from '@/lib/users'
+import { dateString, inputClass } from '@/lib/utils'
-import { cn, dateString, inputClass } from '@/lib/utils'
 import { useValidationErrors } from '@/lib/useValidationErrors'
 
-import type { FC, FormEvent, ReactNode } from 'react'
+import type { FC } from 'react'
 
-import type { NiconicoViewerHandle,
+import type { NiconicoMetadata,
+	      NiconicoViewerHandle,
 	      Post,
-	      Category,
-	      Tag,
 	      Theatre,
-	      TheatreComment,
+	      TheatreComment } from '@/types'
-	      TheatreInfo,
+
-	      TheatrePostSelectionWeights,
+type TheatreInfo = {
-	      TheatreProgramme,
+    hostFlg:        boolean
-	      User } from '@/types'
+    postId:         number | null
+    postStartedAt:  string | null
+    watchingUsers:  { id: number; name: string }[] }
 
 type TheatreCommentField = 'content'
-type TheatreLayoutMode = 'threeColumns' | 'tagsBottom' | 'commentsBottom'
-type TagFlow = 'vertical' | 'horizontal'
 
-const INITIAL_THEATRE_INFO: TheatreInfo =
+const INITIAL_THEATRE_INFO =
     { hostFlg: false,
       postId: null,
       postStartedAt: null,
-      postElapsedMs: null,
+      watchingUsers: [] as { id: number; name: string }[] } as const
-      watchingUsers: [],
-      skipVote: { votesCount: 0,
-		  requiredCount: 1,
-		  watchingUsersCount: 0,
-		  voted: false } }
-
-const INITIAL_WEIGHTS: TheatrePostSelectionWeights =
-    { tagPenalties: [], lightestPosts: [], heaviestPosts: [] }
-
-const LAYOUT_STORAGE_KEY = 'theatre-layout-mode'
-const TAG_FLOW_STORAGE_KEY = 'theatre-tag-flow'
-
-const LAYOUT_LABELS: Record<TheatreLayoutMode, string> = {
-    threeColumns:   '3 列',
-    tagsBottom:     '2 列 A 型',
-    commentsBottom: '2 列 B 型' }
-
-const TAG_FLOW_LABELS: Record<TagFlow, string> = {
-    vertical:   '縦並び',
-    horizontal: '横並び' }
 
 
-const userName = (user: Pick<User, 'id' | 'name'> | null | undefined): string =>
+const TheatreDetailPage: FC = () => {
-    user ? (user.name || `名もなきニジラー（#${ user.id }）`) : '運営'
-
-
-const commentBox = (
-    comment: TheatreComment,
-    programme: TheatreProgramme | null = null,
-): ReactNode[] =>
-    [(
-	<div key={`${ comment.no }-content`} className="w-full">
-	  {comment.deleted
-	   ? <span className="text-sm font-bold">削除されました．</span>
-	   : comment.content}
-	</div>),
-     (
-	<div key={`${ comment.no }-user`} className="w-full text-sm text-right">
-	  by {userName (comment.user)}
-	</div>),
-     (
-	<div key={`${ comment.no }-createdAt`} className="w-full text-sm text-right">
-	  {dateString (comment.createdAt)}
-	</div>),
-     (
-	<div
-	    key={`${ comment.no }-post`}
-	    className="mt-1 w-full text-xs text-zinc-500 dark:text-zinc-400">
-	  {programme && (
-	      <>
-		<PrefetchLink to={`/posts/${ programme.post.id }`} className="font-bold hover:underline">
-		  {programme.post.title || programme.post.url}
-		</PrefetchLink>
-		&thinsp;へのコメント
-	      </>)}
-	</div>)]
-
-
-const compareTagName = (a: Tag, b: Tag): number =>
-    a.name === b.name ? 0 : (a.name < b.name ? -1 : 1)
-
-
-const tagsByCategory = (tags: Tag[]): Partial<Record<Category, Tag[]>> => {
-  const grouped: Partial<Record<Category, Tag[]>> = { }
-
-  for (const tag of tags)
-    {
-      grouped[tag.category] ??= []
-      grouped[tag.category]!.push (tag)
-    }
-
-  for (const cat of CATEGORIES)
-    grouped[cat]?.sort (compareTagName)
-
-  return grouped
-}
-
-
-const TagList: FC<{ tags: Tag[]; compact?: boolean; flow?: TagFlow }> = (
-    { tags, compact, flow = 'vertical' },
-) => {
-  const grouped = tagsByCategory (tags)
-
-  if (flow === 'horizontal')
-    {
-      return (
-	  <ul className={cn ('flex flex-wrap gap-x-3 gap-y-1', compact && 'text-sm')}>
-	    {CATEGORIES.flatMap (cat => grouped[cat] ?? []).map (tag => (
-		<li key={tag.id} className="text-left leading-tight">
-		  <TagLink tag={tag} withCount={false}/>
-		</li>))}
-	  </ul>)
-    }
-
-  return (
-      <div className="space-y-3">
-	{CATEGORIES.map (cat => {
-	  const rows = grouped[cat] ?? []
-	  if (rows.length === 0)
-	    return null
-
-	  return (
-	      <div key={cat}>
-		<div className="mb-1 shrink-0 text-xs font-bold text-zinc-500 dark:text-zinc-400">
-		  {CATEGORY_NAMES[cat]}
-		</div>
-		<ul className={cn ('space-y-1', compact && 'text-sm')}>
-		  {rows.map (tag => (
-		      <li key={tag.id} className="text-left leading-tight">
-			<TagLink tag={tag} withCount={false}/>
-		      </li>))}
-		</ul>
-	      </div>)
-	})}
-      </div>)
-}
-
-
-type Props = { user: User | null }
-
-
-const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
   const { id } = useParams ()
-  const dialogue = useDialogue ()
 
   const commentsRef = useRef<HTMLDivElement> (null)
   const embedRef = useRef<NiconicoViewerHandle> (null)
   const loadingRef = useRef (false)
   const theatreInfoRef = useRef<TheatreInfo> (INITIAL_THEATRE_INFO)
-  const theatreInfoReceivedAtRef = useRef (performance.now ())
   const videoLengthRef = useRef (0)
   const lastCommentNoRef = useRef (0)
 
   const [comments, setComments] = useState<TheatreComment[]> ([])
   const [content, setContent] = useState ('')
-  const [editingPost, setEditingPost] = useState<Post | null> (null)
   const [loading, setLoading] = useState (false)
-  const [programmes, setProgrammes] = useState<TheatreProgramme[]> ([])
   const [sending, setSending] = useState (false)
   const [status, setStatus] = useState (200)
   const [theatre, setTheatre] = useState<Theatre | null> (null)
   const [theatreInfo, setTheatreInfo] = useState<TheatreInfo> (INITIAL_THEATRE_INFO)
   const [post, setPost] = useState<Post | null> (null)
   const [videoLength, setVideoLength] = useState (0)
-  const [weights, setWeights] = useState<TheatrePostSelectionWeights> (INITIAL_WEIGHTS)
-  const [layoutMode, setLayoutMode] = useState<TheatreLayoutMode> (() => {
-    const stored = localStorage.getItem (LAYOUT_STORAGE_KEY)
-    return (
-	((['threeColumns', 'tagsBottom', 'commentsBottom'] as TheatreLayoutMode[])
-	 .includes (stored as TheatreLayoutMode))
-	? (stored as TheatreLayoutMode)
-	: 'threeColumns')
-  })
-  const [tagFlow, setTagFlow] = useState<TagFlow> (() => {
-    const stored = localStorage.getItem (TAG_FLOW_STORAGE_KEY)
-    return (
-	(['vertical', 'horizontal'] as TagFlow[]).includes (stored as TagFlow)
-	? (stored as TagFlow)
-	: 'vertical')
-  })
   const { fieldErrors, clearValidationErrors, applyValidationError } =
       useValidationErrors<TheatreCommentField> ()
 
-  const changeLayoutMode = (mode: TheatreLayoutMode) => {
-    setLayoutMode (mode)
-    localStorage.setItem (LAYOUT_STORAGE_KEY, mode)
-  }
-
-  const changeTagFlow = (flow: TagFlow) => {
-    setTagFlow (flow)
-    localStorage.setItem (TAG_FLOW_STORAGE_KEY, flow)
-  }
-
-  const applyTheatreInfo = useCallback ((nextInfo: TheatreInfo) => {
-    theatreInfoReceivedAtRef.current = performance.now ()
-    setTheatreInfo (nextInfo)
-  }, [])
-
-  const currentPostElapsedMs = useCallback (
-      (info: TheatreInfo = theatreInfoRef.current): number => {
-	if (info.postElapsedMs == null)
-	  return 0
-
-	return Math.max (
-	    info.postElapsedMs + performance.now () - theatreInfoReceivedAtRef.current,
-	    0)
-      }, [])
-
-  const refreshProgrammes = useCallback (async () => {
-    if (!(id))
-      return
-
-    setProgrammes (await apiGet<TheatreProgramme[]> (
-	`/theatres/${ id }/programmes`, { params: { limit: '100' } }))
-  }, [id])
-
-  const refreshWeights = useCallback (async () => {
-    if (!(id))
-      return
-
-    setWeights (await apiGet<TheatrePostSelectionWeights> (
-	`/theatres/${ id }/post_selection_weights`))
-  }, [id])
-
-  const advancePost = useCallback (async () => {
-    if (!(id))
-      return
-
-    setLoading (true)
-    try
-    {
-      await apiPatch<void> (`/theatres/${ id }/next_post`)
-      await refreshProgrammes ()
-      await refreshWeights ()
-    }
-    catch (error)
-    {
-      console.error (error)
-    }
-    finally
-    {
-      setLoading (false)
-    }
-  }, [id, refreshProgrammes, refreshWeights])
-
   useEffect (() => {
     loadingRef.current = loading
   }, [loading])
@@ -289,14 +83,10 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
     let cancelled = false
 
     setComments ([])
-    setEditingPost (null)
-    setPost (null)
-    setProgrammes ([])
     setTheatre (null)
-    theatreInfoReceivedAtRef.current = performance.now ()
+    setPost (null)
     setTheatreInfo (INITIAL_THEATRE_INFO)
     setVideoLength (0)
-    setWeights (INITIAL_WEIGHTS)
     lastCommentNoRef.current = 0
 
     void (async () => {
@@ -312,13 +102,10 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
       }
     }) ()
 
-    void refreshProgrammes ()
-    void refreshWeights ()
-
     return () => {
       cancelled = true
     }
-  }, [id, refreshProgrammes, refreshWeights])
+  }, [id])
 
   useEffect (() => {
     if (!(id))
@@ -337,11 +124,11 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
       {
 	const newComments = await apiGet<TheatreComment[]> (
 	    `/theatres/${ id }/comments`,
-	    { params: { no_gt: lastCommentNoRef.current, limit: '20' } })
+	    { params: { no_gt: lastCommentNoRef.current } })
 
 	if (!(cancelled) && newComments.length > 0)
 	  {
-	    lastCommentNoRef.current = newComments[0].no
+	    lastCommentNoRef.current = newComments[newComments.length - 1].no
 	    setComments (prev => [...newComments, ...prev])
 	  }
 
@@ -349,26 +136,20 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
 	const ended =
 	    currentInfo.hostFlg
 	    && currentInfo.postStartedAt
-	    && videoLengthRef.current > 0
+	    && ((Date.now () - (new Date (currentInfo.postStartedAt)).getTime ())
-	    && currentPostElapsedMs (currentInfo) > videoLengthRef.current + 3_000
+	        > videoLengthRef.current + 3_000)
 
 	if (ended)
 	  {
 	    if (!(cancelled))
-	      {
+	      setTheatreInfo (prev => ({ ...prev, postId: null, postStartedAt: null }))
-		setTheatreInfo (prev => ({
-		    ...prev,
-		    postId: null,
-		    postStartedAt: null,
-		    postElapsedMs: null }))
-	      }
 
 	    return
 	  }
 
 	const nextInfo = await apiPut<TheatreInfo> (`/theatres/${ id }/watching`)
 	if (!(cancelled))
-	  applyTheatreInfo (nextInfo)
+	  setTheatreInfo (nextInfo)
       }
       catch (error)
       {
@@ -387,7 +168,7 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
       cancelled = true
       clearInterval (interval)
     }
-  }, [applyTheatreInfo, currentPostElapsedMs, id])
+  }, [id])
 
   useEffect (() => {
     if (!(id) || !(theatreInfo.hostFlg) || loadingRef.current || theatreInfo.postId != null)
@@ -396,24 +177,33 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
     let cancelled = false
 
     void (async () => {
-      await advancePost ()
+      setLoading (true)
-      if (cancelled)
+
+      try
+      {
+	await apiPatch<void> (`/theatres/${ id }/next_post`)
+      }
+      catch (error)
+      {
+	console.error (error)
+      }
+      finally
+      {
+	if (!(cancelled))
 	  setLoading (false)
+      }
     }) ()
 
     return () => {
       cancelled = true
     }
-  }, [advancePost, id, theatreInfo.hostFlg, theatreInfo.postId])
+  }, [id, theatreInfo.hostFlg, theatreInfo.postId])
 
   useEffect (() => {
     setVideoLength (0)
 
     if (theatreInfo.postId == null)
-      {
-	setPost (null)
       return
-      }
 
     let cancelled = false
 
@@ -435,118 +225,63 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
     }
   }, [theatreInfo.postId])
 
-  useEffect (() => {
+  const syncPlayback = (meta: NiconicoMetadata) => {
-    void refreshProgrammes ()
-  }, [refreshProgrammes, theatreInfo.postId])
-
-  const syncPlaybackTime = (currentTimeMs: number): number | void => {
     if (!(theatreInfo.postStartedAt))
       return
 
-    const currentVideoLength = videoLengthRef.current
-    if (currentVideoLength <= 0)
-      return
-
     const targetTime = Math.min (
-	currentPostElapsedMs (theatreInfo),
+	Math.max (0, Date.now () - (new Date (theatreInfo.postStartedAt)).getTime ()),
-	currentVideoLength)
+	videoLength)
 
-    const drift = Math.abs (currentTimeMs - targetTime)
+    const drift = Math.abs (meta.currentTime - targetTime)
 
     if (drift > 5_000)
       embedRef.current?.seek (targetTime)
-
-    return targetTime
   }
 
-  const handlePlaybackError = async () => {
+  if (status >= 400)
-    if (!(theatreInfoRef.current.hostFlg) || loadingRef.current)
+    return <ErrorScreen status={status}/>
-      return
 
-    loadingRef.current = true
+  return (
-    try
+      <div className="md:flex md:flex-1 overflow-y-auto md:overflow-y-hidden">
-    {
+	<Helmet>
-      await advancePost ()
+	  {theatre && (
-    }
+	      <title>
-    finally
+		{'上映会場'
-    {
+		 + (theatre.name ? `『${ theatre.name }』` : ` #${ theatre.id }`)
-      loadingRef.current = false
+		 + ` | ${ SITE_TITLE }`}
-    }
+	      </title>)}
-  }
+	</Helmet>
 
-  const handleVideoReady = (durationMs: number) => {
+	<div className="hidden md:block">
-    const playableDurationMs =
+	  {post && <TagDetailSidebar post={post}/>}
-	Number.isFinite (durationMs)
+	</div>
-	? durationMs
-	: 0
-
-    setVideoLength (playableDurationMs)
-    videoLengthRef.current = playableDurationMs
-
-    if (playableDurationMs <= 0)
-      {
-	void handlePlaybackError ()
-	return
-      }
 
+	<MainArea>
+	  {post ? (
+	      <>
+		<PostEmbed
+		    key={post.id}
+		    ref={embedRef}
+		    post={post}
+		    onLoadComplete={info => {
 		      embedRef.current?.play ()
-  }
+		      setVideoLength (info.lengthInSeconds * 1_000)
+		    }}
+		    onMetadataChange={syncPlayback}/>
+		<div className="m-2">
+		  <>再生中：</>
+		  <PrefetchLink to={`/posts/${ post.id }`} className="font-bold">
+		    {post.title || post.url}
+		  </PrefetchLink>
+		</div>
+	      </>) : 'Loading...'}
+	</MainArea>
 
-  const handleSkipVote = async () => {
+	<SidebarComponent>
-    if (!(id) || !(post))
+	  <form
-      return
+	      className="w-auto h-auto border border-black dark:border-white rounded mx-2"
-
+	      onSubmit={async e => {
-    setLoading (true)
-    try
-    {
-      const nextInfo =
-	  theatreInfo.skipVote.voted
-	  ? await apiDelete<TheatreInfo> (
-	      `/theatres/${ id }/skip_vote`, { params: { post_id: post.id } })
-	  : await apiPut<TheatreInfo> (
-	      `/theatres/${ id }/skip_vote`, { post_id: post.id })
-
-      applyTheatreInfo (nextInfo)
-
-      if (nextInfo.skipped)
-	{
-	  setPost (null)
-	  await refreshProgrammes ()
-	  await refreshWeights ()
-	}
-    }
-    catch (error)
-    {
-      if (isApiError (error) && error.response?.status === 409)
-	applyTheatreInfo (await apiPut<TheatreInfo> (`/theatres/${ id }/watching`))
-
-      console.error (error)
-    }
-    finally
-    {
-      setLoading (false)
-    }
-  }
-
-  const handleDelete = async (commentNo: number) => {
-    try
-    {
-      await apiDelete (`/theatres/${ id }/comments/${ commentNo }`)
-      setComments (prev => {
-	const rtn = [...prev]
-	const idx = rtn.findIndex (x => x.no === commentNo)
-	if (idx >= 0)
-	  rtn[idx] = { ...rtn[idx], deleted: true, content: null }
-	return rtn
-      })
-    }
-    catch
-    {
-      ;
-    }
-  }
-
-  const handleCommentSubmit = async (e: FormEvent) => {
 		e.preventDefault ()
 
 		if (!(content))
@@ -568,61 +303,7 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
 		{
 		  setSending (false)
 		}
-  }
+	      }}>
-
-  const skipVote = theatreInfo.skipVote
-  const theatreTitle = theatre?.name ? `上映会場『${ theatre.name }』` : '上映会場'
-  const postTags = post?.tags ?? []
-  const programmesAsc = useMemo (
-      () => [...programmes].sort (
-	  (a, b) => Date.parse (a.createdAt) - Date.parse (b.createdAt)),
-      [programmes])
-
-  const programmeForComment = useCallback ((comment: TheatreComment): TheatreProgramme | null => {
-    const commentedAt = Date.parse (comment.createdAt)
-    let found: TheatreProgramme | null = null
-
-    for (const programme of programmesAsc)
-      {
-	const startedAt = Date.parse (programme.createdAt)
-	if (startedAt > commentedAt)
-	  break
-
-	found = programme
-      }
-
-    return found
-  }, [programmesAsc])
-
-  if (status >= 400)
-    return <ErrorScreen status={status}/>
-
-  const tagPanel = (
-      <section className="rounded border-zinc-300 p-4 dark:border-zinc-800">
-	<div className="mb-3 flex items-center justify-between gap-3">
-	  <h2 className="font-bold">タグ</h2>
-	  {layoutMode === 'tagsBottom' && (
-	      <div className="hidden gap-2 md:flex">
-		{(Object.keys (TAG_FLOW_LABELS) as TagFlow[]).map (flow => (
-		    <Button
-			key={flow}
-			type="button"
-			size="sm"
-			variant={tagFlow === flow ? 'default' : 'outline'}
-			onClick={() => changeTagFlow (flow)}>
-		      {TAG_FLOW_LABELS[flow]}
-		    </Button>))}
-	      </div>)}
-	</div>
-	{postTags.length === 0
-	 ? <div className="text-sm text-zinc-500">タグはありません。</div>
-	 : <TagList tags={postTags} flow={layoutMode === 'tagsBottom' ? tagFlow : 'vertical'}/>}
-      </section>)
-
-  const commentsPanel = (
-      <section className="rounded border-zinc-300 p-4 dark:border-zinc-800">
-	<h2 className="mb-3 font-bold">コメント</h2>
-	<form onSubmit={handleCommentSubmit}>
 	    <input
 		className={inputClass ((fieldErrors.content ?? []).length > 0)}
 		type="text"
@@ -631,330 +312,49 @@ const TheatreDetailPage: FC<Props> = ({ user }: Props) => {
 		onChange={e => setContent (e.target.value)}
 		disabled={sending}/>
 	    <FieldError messages={fieldErrors.content}/>
-	</form>
 
 	    <div
 		ref={commentsRef}
-	    className="mt-3 max-h-[48vh] overflow-y-auto rounded border border-zinc-200
+		className="overflow-x-hidden overflow-y-scroll text-wrap w-full
-		       dark:border-zinc-800">
+			   h-[32vh] md:h-[64vh] border rounded">
-	  {comments.map (comment => {
+	      {comments.map (comment => (
-	    const commentProgramme = programmeForComment (comment)
+		  <div key={comment.no} className="p-2">
-	    return (
+		    <div className="w-full">
-		<div
+		      {comment.content}
-		    key={comment.no}
+		    </div>
-		    className="group relative border-t border-zinc-100 p-2 first:border-t-0
+		    <div className="w-full text-sm text-right">
-			       hover:bg-zinc-50 dark:border-zinc-800 dark:hover:bg-zinc-800">
+		      by {comment.user
-		  {(user && comment.user?.id === user.id && !(comment.deleted)) && (
+			  ? (comment.user.name || `名もなきニジラー（#${ comment.user.id }）`)
-		      <button
+			  : '運営'}
-			  type="button"
+		    </div>
-			  className="absolute left-1 top-1 hidden rounded px-1 text-red-600
+		    <div className="w-full text-sm text-right">
-				     hover:bg-red-100 group-hover:inline-block dark:text-red-300
+		      {dateString (comment.createdAt)}
-				     dark:hover:bg-red-950"
-			  aria-label="コメントを削除"
-			  onClick={async e => {
-			    e.stopPropagation ()
-
-			    if (!(await dialogue.confirm ({
-				title: 'このコメントを削除しますか?',
-				description: (
-				    <div className="my-3 w-120 rounded border border-black p-2
-						    dark:border-white">
-				      {commentBox (comment, commentProgramme)}
-				    </div>),
-				confirmText: '削除',
-				variant: 'danger' })))
-			      return
-
-			    await handleDelete (comment.no)
-			  }}>
-			&times;
-		      </button>)}
-		  {commentBox (comment, commentProgramme)}
-		</div>)
-	  })}
 		    </div>
-      </section>)
-
-  const participantsPanel = (
-      <section className="rounded border-zinc-300 p-4 dark:border-zinc-800">
-	<h2 className="mb-3 font-bold">参加者</h2>
-	<div className="space-y-1">
-	  {theatreInfo.watchingUsers.map (watchingUser => (
-	      <div key={watchingUser.id} className="flex justify-between gap-2 text-sm">
-		<span>{userName (watchingUser)}</span>
-		{watchingUser.id === user?.id && <span className="text-zinc-500">お前</span>}
 		  </div>))}
 	    </div>
-      </section>)
+	  </form>
 
-  const historyPanel = (
+	  <div className="w-auto h-auto border border-black dark:border-white rounded mx-2 mt-4">
-      <section className="rounded border-zinc-300 p-4 dark:border-zinc-800">
+	    <div className="p-2">
-	<h2 className="mb-3 font-bold">再生履歴</h2>
+		現在の同接数：{theatreInfo.watchingUsers.length}
-	<div className="rounded border border-zinc-300 dark:border-zinc-800 max-h-72
-			overflow-y-auto">
-	  {programmes.length === 0
-	   ? <div className="text-sm text-zinc-500">まだ履歴はありません。</div>
-	   : (
-	      programmes.map (programme => (
-		  <div
-		      key={`${ programme.theatreId }-${ programme.position }`}
-		      className="border-zinc-100 p-2 text-sm first:border-t-0
-				 dark:border-zinc-800">
-		    <PrefetchLink
-			to={`/posts/${ programme.post.id }`}
-			className="font-bold hover:underline">
-		      {programme.post.title || programme.post.url}
-		    </PrefetchLink>
-		    <div className="text-xs text-zinc-500">
-		      {dateString (programme.createdAt)}
-		    </div>
-		  </div>)))}
-	</div>
-      </section>)
-
-  const weightsPanel = (
-      <section className="rounded border-zinc-300 p-4 dark:border-zinc-800">
-	<div className="mb-3 flex items-center justify-between gap-3">
-	  <h2 className="font-bold">抽選重み</h2>
-	  <Button type="button" variant="outline" size="sm" onClick={() => void refreshWeights ()}>
-	    更新
-	  </Button>
 	    </div>
 
-	<div className="mx-4 grid gap-16 xl:grid-cols-3">
+	    <div className="overflow-x-hidden overflow-y-scroll text-wrap w-full h-32
-	  <div>
+			    border rounded">
-	    <h3 className="mb-2 text-sm font-bold">出にくいタグ</h3>
+	      <ul className="list-inside list-disc">
-	    <div className="space-y-1 text-sm">
+		{theatreInfo.watchingUsers.map (user => (
-	      {weights.tagPenalties.length === 0
+		    <li key={user.id} className="px-4 py-1 text-sm">
-	       ? <div className="text-zinc-500">まだ減点はありません。</div>
+		      {user.name || `名もなきニジラー（#${ user.id }）`}
-	       : (
+		    </li>))}
-		  weights.tagPenalties.slice (0, 12).map (row => (
+	      </ul>
-		      <div
-			  key={row.tag.id}
-			  className="grid grid-cols-[minmax(0,1fr)_auto] items-baseline gap-2
-				     text-left">
-			<div className="min-w-0 text-left">
-			  <TagLink tag={row.tag} withCount={false}/>
-			</div>
-			<span className="font-mono">{row.penalty}</span>
-		      </div>)))}
 	    </div>
 	  </div>
-
+	</SidebarComponent>
-	  <div>
-	    <h3 className="mb-2 text-sm font-bold">出にくい候補</h3>
-	    <WeightRows rows={weights.lightestPosts}/>
-	  </div>
-
-	  <div>
-	    <h3 className="mb-2 text-sm font-bold">出やすい候補</h3>
-	    <WeightRows rows={weights.heaviestPosts}/>
-	  </div>
-	</div>
-      </section>)
-
-  return (
-      <motion.div
-	  layout="position"
-	  transition={{ layout: { duration: .2, ease: 'easeOut' } }}
-	  className="min-h-0 flex-1 overflow-y-auto bg-zinc-50 text-zinc-950
-		     md:overflow-hidden dark:bg-zinc-950 dark:text-zinc-50">
-	<Helmet>
-	  <meta name="robots" content="noindex"/>
-	  {theatre && <title>{`${ theatreTitle } | ${ SITE_TITLE }`}</title>}
-	</Helmet>
-
-	<div className={cn (
-	    'grid min-h-full gap-4 overflow-visible md:h-full md:overflow-hidden',
-	    (layoutMode === 'threeColumns'
-	     && ['md:grid-cols-[16rem_minmax(0,1fr)_22rem]',
-		 'xl:grid-cols-[18rem_minmax(0,1fr)_24rem]']),
-	    (layoutMode === 'tagsBottom'
-	     && 'md:grid-cols-[minmax(0,1fr)_22rem] xl:grid-cols-[minmax(0,1fr)_24rem]'),
-	    (layoutMode === 'commentsBottom'
-	     && 'md:grid-cols-[16rem_minmax(0,1fr)] xl:grid-cols-[18rem_minmax(0,1fr)]'))}>
-	  {layoutMode !== 'tagsBottom' && (
-	      <motion.aside
-		  layout="position"
-		  className="hidden min-w-0 space-y-4 md:order-none md:block md:overflow-y-auto
-			     md:[direction:rtl]">
-		<div className="md:[direction:ltr]">
-		  {tagPanel}
-		</div>
-	      </motion.aside>)}
-
-	  <motion.main
-	      layout="position"
-	      className={cn ('order-1 min-w-0 space-y-4 md:order-none md:overflow-y-auto',
-			     layoutMode === 'tagsBottom' && 'md:[direction:rtl]')}>
-	    <div className={cn ('space-y-4', layoutMode === 'tagsBottom' && 'md:[direction:ltr]')}>
-	      <section className="overflow-hidden rounded border-zinc-300
-				  dark:border-zinc-800">
-		<div className="flex flex-wrap items-center justify-between gap-3
-				border-zinc-200 px-4 py-3 dark:border-zinc-800">
-		  <div>
-		    <h1 className="text-lg font-bold">{theatreTitle}</h1>
-		    <p className="text-sm text-zinc-500 dark:text-zinc-400">
-		      同接 {theatreInfo.watchingUsers.length} 人
-		    </p>
-		  </div>
-
-		  <div className="flex flex-wrap gap-2">
-		    <div className="hidden flex-wrap gap-2 md:flex">
-		      {(Object.keys (LAYOUT_LABELS) as TheatreLayoutMode[]).map (mode => (
-			  <Button
-			      key={mode}
-			      type="button"
-			      size="sm"
-			      variant={layoutMode === mode ? 'default' : 'outline'}
-			      onClick={() => changeLayoutMode (mode)}>
-			    {LAYOUT_LABELS[mode]}
-			  </Button>))}
-		    </div>
-
-		    <Button
-			type="button"
-			size="sm"
-			variant={skipVote.voted ? 'secondary' : 'destructive'}
-			disabled={loading || !(post)}
-			onClick={handleSkipVote}>
-		      {skipVote.voted ? 'スキップ取消' : 'スキップ'}
-		      {` ${ skipVote.votesCount } / ${ skipVote.requiredCount }`}
-		    </Button>
-
-		  </div>
-		</div>
-
-		<div className="flex justify-center bg-black mx-4">
-		  {post ? (
-		      <PostEmbed
-			  key={post.id}
-			  ref={embedRef}
-			  post={post}
-			  onVideoReady={handleVideoReady}
-			  onPlaybackChange={syncPlaybackTime}
-			  onError={handlePlaybackError}/>) : (
-		      <div className="grid min-h-72 place-items-center text-zinc-400">
-			{loading ? '次の投稿を選んでゐます……' : '上映待機中'}
-		      </div>)}
-		</div>
-
-		<div className="flex flex-wrap items-center justify-between gap-3 px-4 py-3">
-		  <div className="min-w-0">
-		    <div className="text-xs font-bold text-zinc-500 dark:text-zinc-400">
-		      再生中
-		    </div>
-		    {post ? (
-			<PrefetchLink
-			    to={`/posts/${ post.id }`}
-			    className="font-bold hover:underline">
-			  {post.title || post.url}
-			</PrefetchLink>) : (
-			<span className="text-zinc-500">未選択</span>)}
-		  </div>
-
-		  {(post && canEditContent (user)) && (
-		      <Button
-			  type="button"
-			  size="sm"
-			  variant="outline"
-			  disabled={!(post)}
-			  onClick={() => post && setEditingPost (ep => ep ? null : post)}>
-			{editingPost ? '閉じる' : '編輯'}
-		      </Button>)}
-		</div>
-	      </section>
-
-	      {editingPost && (
-		  <section className="rounded border border-amber-300 bg-amber-50 mx-4 p-4
-				      dark:border-amber-800 dark:bg-amber-950/30">
-		    <div className="mb-3">
-		      <h2 className="font-bold">編輯中の投稿</h2>
-		      <p className="text-sm text-amber-900 dark:text-amber-100">
-			<PrefetchLink
-			    to={`/posts/${ editingPost.id }`}
-			    className="mx-1 font-bold underline">
-			  {editingPost.title || editingPost.url}
-			</PrefetchLink>
-			を編輯中……
-		      </p>
-		    </div>
-
-		    <PostEditForm
-			post={editingPost}
-			onSave={newPost => {
-			  setEditingPost (newPost)
-			  if (post?.id === newPost.id)
-			    setPost (newPost)
-			  void refreshWeights ()
-			}}/>
-		  </section>)}
 
 	<div className="md:hidden">
-		{commentsPanel}
+	  {post && <TagDetailSidebar post={post} sp/>}
 	</div>
-
+      </div>)
-	      {layoutMode === 'commentsBottom' && (
-		  <div className="hidden md:block">
-		    {commentsPanel}
-		  </div>)}
-
-	      <div className="md:hidden">
-		{tagPanel}
-	      </div>
-
-	      {layoutMode === 'tagsBottom' && (
-		  <div className="hidden md:block">
-		    {tagPanel}
-		  </div>)}
-
-	      {historyPanel}
-	      {weightsPanel}
-
-	      <div className="md:hidden">
-		{participantsPanel}
-	      </div>
-
-	      {layoutMode === 'commentsBottom' && (
-		  <div className="hidden md:block">
-		    {participantsPanel}
-		  </div>)}
-	    </div>
-	  </motion.main>
-
-	  {layoutMode !== 'commentsBottom' && (
-	      <motion.aside
-		  layout="position"
-		  className="hidden min-w-0 space-y-4 md:order-none md:block md:overflow-y-auto">
-		{commentsPanel}
-		{participantsPanel}
-	      </motion.aside>)}
-	</div>
-      </motion.div>)
 }
 
-
-const WeightRows: FC<{ rows: TheatrePostSelectionWeights['lightestPosts'] }> = ({ rows }) => (
-    <div className="space-y-2 text-sm">
-      {rows.length === 0
-       ? <div className="text-zinc-500">候補はありません。</div>
-       : (
-	  rows.slice (0, 8).map (row => (
-	      <div
-		  key={row.post.id}
-		  className="border-zinc-100 pt-2 first:border-t-0 first:pt-0
-			     dark:border-zinc-800">
-		<PrefetchLink
-		    to={`/posts/${ row.post.id }`}
-		    className="line-clamp-1 font-bold hover:underline">
-		  {row.post.title || row.post.url}
-		</PrefetchLink>
-		<div className="flex justify-between gap-2 text-xs text-zinc-500">
-		  <span>penalty {row.penalty}</span>
-		  <span>weight {row.weight.toFixed (3)}</span>
-		</div>
-	      </div>)))}
-    </div>)
-
-
 export default TheatreDetailPage

frontend/src/test/factories.ts

@@ -1,13 +1,4 @@
-import type { Material,
+import type { Material, Post, Tag, User, WikiPage } from '@/types'
-	      Post,
-	      Tag,
-	      Theatre,
-	      TheatreComment,
-	      TheatreInfo,
-	      TheatrePostSelectionWeights,
-	      TheatreProgramme,
-	      User,
-	      WikiPage } from '@/types'
 
 export const buildTag = (overrides: Partial<Tag> = {}): Tag => ({
   id:             1,
@@ -81,62 +72,3 @@ export const buildMaterial = (overrides: Partial<Material> = {}): Material => ({
   updatedByUser: { id: 2, name: 'updater' },
   ...overrides,
 })
-
-export const buildTheatre = (overrides: Partial<Theatre> = {}): Theatre => ({
-  id:            1,
-  name:          'テスト劇場',
-  opensAt:       '2026-01-02T03:04:05.000Z',
-  closesAt:      null,
-  createdByUser: { id: 1, name: 'creator' },
-  createdAt:     '2026-01-02T03:04:05.000Z',
-  updatedAt:     '2026-01-03T03:04:05.000Z',
-  ...overrides,
-})
-
-export const buildTheatreInfo = (
-    overrides: Partial<TheatreInfo> = {},
-): TheatreInfo => ({
-  hostFlg:       false,
-  postId:        null,
-  postStartedAt: null,
-  postElapsedMs: null,
-  watchingUsers: [],
-  skipVote:      {
-    votesCount:         0,
-    requiredCount:      1,
-    watchingUsersCount: 0,
-    voted:              false,
-  },
-  ...overrides,
-})
-
-export const buildTheatreComment = (
-    overrides: Partial<TheatreComment> = {},
-): TheatreComment => ({
-  theatreId: 1,
-  no:        1,
-  deleted:   false,
-  user:      { id: 1, name: 'tester' },
-  content:   'テストコメント',
-  createdAt: '2026-01-02T03:04:05.000Z',
-  ...overrides,
-} as TheatreComment)
-
-export const buildTheatreProgramme = (
-    overrides: Partial<TheatreProgramme> = {},
-): TheatreProgramme => ({
-  theatreId: 1,
-  position:  1,
-  post:      buildPost (),
-  createdAt: '2026-01-02T03:04:05.000Z',
-  ...overrides,
-})
-
-export const buildTheatrePostSelectionWeights = (
-    overrides: Partial<TheatrePostSelectionWeights> = {},
-): TheatrePostSelectionWeights => ({
-  tagPenalties:  [],
-  lightestPosts: [],
-  heaviestPosts: [],
-  ...overrides,
-})

frontend/src/types.ts

@@ -223,63 +223,12 @@ export type Theatre = {
     createdAt:      string
     updatedAt:      string }
 
-export type TheatreComment =
+export type TheatreComment = {
-    | { theatreId:  number
+    theatreId:  number,
-	no:         number
+    no:         number,
-	deleted:    false
     user:       { id: number, name: string } | null
     content:    string
     createdAt:  string }
-    | { theatreId:  number
-	no:         number
-	deleted:    true
-	user:       { id: number, name: string } | null
-	content:    null,
-	createdAt:  string }
-
-export type TheatreProgramme = {
-    theatreId:  number
-    position:   number
-    post:       Post
-    createdAt:  string }
-
-export type TheatreSkipVoteStatus = {
-    votesCount:          number
-    requiredCount:       number
-    watchingUsersCount:  number
-    voted:               boolean }
-
-export type TheatreInfo = {
-    hostFlg:        boolean
-    postId:         number | null
-    postStartedAt:  string | null
-    postElapsedMs:  number | null
-    watchingUsers:  Pick<User, 'id' | 'name'>[]
-    skipVote:       TheatreSkipVoteStatus
-    skipped?:       boolean }
-
-export type TheatreSkipEvent = {
-    id:                 number
-    theatreId:          number
-    post:               Post
-    tags:               Tag[]
-    programmePosition:  number | null
-    createdAt:          string }
-
-export type TheatrePostWeight = {
-    post:     Post
-    weight:   number
-    penalty:  number
-    tags:     Tag[] }
-
-export type TheatreTagPenalty = {
-    tag:      Tag
-    penalty:  number }
-
-export type TheatrePostSelectionWeights = {
-    tagPenalties:  TheatreTagPenalty[]
-    lightestPosts: TheatrePostWeight[]
-    heaviestPosts: TheatrePostWeight[] }
 
 export type User = {
     id:               number