#106 誤字

.gitea/ISSUE_TEMPLATE.md

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

AGENTS.md

@@ -1,143 +0,0 @@
-# AGENTS.md
-
-## Project overview
-
-BTRC Hub / タグ広場 is a split Rails API and React frontend repository.
-
-- Backend: Rails API under `backend/`.
-- Frontend: React + TypeScript + Vite under `frontend/`.
-- Docs: lightweight command notes under `docs/`.
-- There is no README or Makefile at the repository root as of this inspection.
-
-## Stack
-
-- Backend: Ruby `3.2.2` from `backend/.ruby-version`, Rails `~> 8.0.2`.
-- Backend dependencies include `mysql2`, `sqlite3`, `rspec-rails`, `factory_bot_rails`, `rack-cors`, `jwt`, `discard`, `gollum`, `whenever`, `aws-sdk-s3`, `brakeman`, and `rubocop-rails-omakase`.
-- Frontend: React `^19.1.0`, TypeScript `~5.8.3`, Vite `^6.3.5`.
-- Frontend data/UI dependencies include Axios, TanStack Query, Tailwind CSS, Framer Motion, Radix UI components, lucide-react, MDX/Markdown tooling, and Zustand.
-
-## Main directories
-
-- `backend/app/controllers`: Rails API controllers.
-- `backend/app/models`: Active Record models.
-- `backend/app/representations`: API response representation classes.
-- `backend/app/services`: domain services such as version recording, wiki commit, YouTube sync, and similarity calculation.
-- `backend/config/routes.rb`: API routes.
-- `backend/db/migrate`: migrations.
-- `backend/db/schema.rb`: current schema snapshot.
-- `backend/lib/tasks`: custom Rake tasks.
-- `backend/spec`: RSpec tests.
-- `backend/test`: Rails minitest files that still exist in the tree.
-- `frontend/src/App.tsx`: frontend route definitions and initial user setup.
-- `frontend/src/pages`: page-level React components.
-- `frontend/src/components`: shared and feature components.
-- `frontend/src/lib`: API client helpers, query keys, prefetchers, and domain helpers.
-- `frontend/src/stores`: Zustand stores.
-- `docs/commands.md`: command notes.
-
-## Commands
-
-Only list commands that are backed by files inspected in this repository.
-
-### Backend
-
-The following binstubs exist under `backend/bin`:
-
-```sh
-cd backend
-bin/setup
-bin/dev
-bin/rails
-bin/rake
-bin/rubocop
-bin/brakeman
-bin/kamal
-bin/thrust
-```
-
-Common Rails/Rake usage through existing binstubs:
-
-```sh
-cd backend
-bin/rails db:prepare
-bin/rails db:migrate
-bin/rails routes
-bin/rails server
-bin/rake
-bin/rubocop
-bin/brakeman
-```
-
-RSpec is present in `Gemfile` and `.rspec` exists:
-
-```sh
-cd backend
-bundle exec rspec
-```
-
-### Frontend
-
-The following npm scripts exist in `frontend/package.json`:
-
-```sh
-cd frontend
-npm run dev
-npm run build
-npm run lint
-npm run preview
-```
-
-`npm run build` runs `tsc -b && vite build`, then `postbuild` runs `node scripts/generate-sitemap.js`.
-
-Do not write or report `npm test` as a repository command unless a `test` script is added to `frontend/package.json`.
-
-## Coding style
-
-- Prefer precise, minimal changes.
-- Do not flatter or over-explain.
-- Explain risks directly.
-- Prefer single quotes for strings unless interpolation or escaping makes double quotes better.
-- Ruby: never put a space before method-call parentheses.
-- Ruby: do not use `%w` or `%i`.
-- TypeScript and Python: use GNU-style spacing before parentheses where syntactically valid.
-- Do not add production dependencies without explicit approval.
-
-## Backend rules
-
-- Inspect existing routes, controllers, models, services, and specs before editing backend behavior.
-- For API behavior changes, add or update request specs under `backend/spec/requests`.
-- Prefer RSpec for new backend tests; existing minitest files under `backend/test` do not make minitest the default for new coverage.
-- Do not weaken authentication, BAN user checks, or IP BAN checks.
-- Preserve the `X-Transfer-Code` user identification flow unless the task explicitly changes authentication.
-- Be careful with version tables, `version_no`, optimistic concurrency, wiki revisions, and restore/diff behavior.
-- Be careful with tag names, tag normalization, implications, similarities, and discard behavior.
-- Keep migration files and `backend/db/schema.rb` consistent when changing schema.
-
-## Frontend rules
-
-- Use `frontend/src/lib/api.ts` for API calls so headers and camelCase conversion stay consistent.
-- Add or reuse TanStack Query keys through `frontend/src/lib/queryKeys.ts`; avoid ad hoc query key arrays.
-- Encode URL path-segment values with `encodeURIComponent`.
-- React hooks must be called unconditionally.
-- Keep page-level code under `frontend/src/pages` and shared UI/feature code under `frontend/src/components` unless existing patterns point elsewhere.
-- Match existing Tailwind, component, and import alias conventions.
-
-## Codex workflow
-
-- First inspect existing patterns; do not invent new architecture when a local convention exists.
-- Keep changes scoped to the requested issue.
-- Do not scan or summarize dependency/generated/runtime directories such as `node_modules`, `dist`, `tmp`, `log`, and `storage` unless explicitly needed.
-- Before touching wiki, tag, versioning, BAN, IP BAN, or authentication behavior, inspect the related request specs and service objects.
-- If frontend code changes, run the existing frontend verification commands that apply: `npm run build` and `npm run lint`.
-- 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
-
-A task is complete only when:
-
-- implementation is complete,
-- relevant verification commands pass, or failures are clearly explained,
-- unrelated files are not changed,
-- migrations and schema are consistent when schema changes are made,
-- user-facing behavior is documented when needed.

backend/.rspec

@@ -1 +0,0 @@
---require spec_helper

backend/AGENTS.md

@@ -1,147 +0,0 @@
-# backend/AGENTS.md
-
-## Scope
-
-These rules apply to work under `backend/`.
-
-This is a Rails API app using Active Record, RSpec, request specs, service objects, representation classes, and version tables for post/tag/wiki history.
-
-## Commands
-
-Use commands backed by files and dependencies in this directory:
-
-```sh
-bin/setup
-bin/dev
-bin/rails
-bin/rake
-bin/rubocop
-bin/brakeman
-bundle exec rspec
-```
-
-Common checks:
-
-```sh
-bundle exec rspec
-bin/rubocop
-bin/brakeman
-```
-
-Common Rails commands:
-
-```sh
-bin/rails db:prepare
-bin/rails db:migrate
-bin/rails routes
-bin/rails server
-```
-
-After backend behavior changes, run the relevant RSpec files. For broad backend changes, run:
-
-```sh
-bundle exec rspec
-```
-
-If a command cannot be run or fails, report the exact command and failure.
-
-## Rails structure
-
-- `app/controllers`: API controllers.
-- `app/models`: Active Record models and concerns.
-- `app/representations`: JSON response shaping.
-- `app/services`: domain services such as version recorders, wiki commit, YouTube sync, and similarity calculation.
-- `config/routes.rb`: public API routes.
-- `db/migrate`: migrations.
-- `db/schema.rb`: schema snapshot.
-- `lib/tasks`: custom Rake tasks.
-- `spec`: RSpec tests.
-
-Before changing behavior, inspect the matching route, controller, model, service, representation, and spec.
-
-## Ruby style
-
-- Prefer precise, minimal changes.
-- Use single quotes unless interpolation or escaping makes double quotes better.
-- Do not put a space before Ruby method-call parentheses.
-- Do not use `%w` or `%i` in new Ruby code.
-- Keep comments short and useful; avoid narrating obvious code.
-- Do not add production dependencies without approval.
-
-## Authentication and authorization
-
-- Authentication is handled through the `X-Transfer-Code` header in `ApplicationController#authenticate_user`.
-- `current_user` is set by looking up `User.inheritance_code`.
-- Do not bypass or weaken the `X-Transfer-Code` flow unless the task explicitly changes authentication.
-- Unauthenticated write actions should return `:unauthorized` consistently with existing controllers.
-- Role checks use `User` enum roles: `guest`, `member`, and `admin`.
-- Use `current_user.gte_member?` for member-or-admin write permissions where existing controllers do so.
-- Use `current_user.admin?` only for admin-only paths, such as tag child relationship changes.
-- Do not replace role checks with looser presence checks.
-
-## BAN and IP BAN
-
-- `ApplicationController` runs these before actions in order:
-  - `reject_banned_ip_address!`
-  - `authenticate_user`
-  - `reject_banned_user!`
-- User and IP bans use `banned_at`, not a boolean `banned` column.
-- `User#banned?` and `IpAddress#banned?` check `banned_at.present?`.
-- Do not weaken BAN or IP BAN behavior.
-- If changing request authentication or controller before actions, add or update request specs covering banned users and banned IP addresses.
-
-## RSpec
-
-- Prefer RSpec for new backend tests.
-- Put API behavior coverage under `spec/requests`.
-- Put model behavior under `spec/models`.
-- Put service behavior under `spec/services`.
-- Put Rake task coverage under `spec/tasks`.
-- `spec/rails_helper.rb` loads `spec/support/**/*.rb`.
-- Request specs include `AuthHelper` and `JsonHelper`.
-- `AuthHelper#sign_in_as(user)` stubs `ApplicationController#current_user`; use it when matching existing request spec style.
-- Add or update request specs for API behavior changes, especially status codes, permissions, response shape, and version conflict behavior.
-
-## Migrations
-
-- Keep migrations and `db/schema.rb` consistent.
-- Use reversible migrations where practical; otherwise define explicit `up` and `down`.
-- For data backfills inside migrations, follow the existing pattern of defining migration-local `ActiveRecord::Base` classes with `self.table_name`.
-- Preserve existing indexes, foreign keys, check constraints, and null constraints.
-- Be careful with MySQL-specific options already present in migrations, such as `after:`.
-- Do not edit old migrations just to change current behavior unless explicitly requested; add a new migration.
-
-## Version tables
-
-- Versioned records include posts, tags, nico tags, and wiki pages.
-- Current records have `version_no`; version tables have positive `version_no` with unique indexes scoped to the parent record.
-- Version event types are `create`, `update`, `discard`, and `restore`.
-- Version rows are readonly through the `VersionRecord` concern.
-- Use the existing recorder services instead of manually inserting version rows in application code:
-  - `PostVersionRecorder`
-  - `TagVersionRecorder`
-  - `NicoTagVersionRecorder`
-  - `WikiVersionRecorder`
-  - `TagVersioning`
-- `VersionRecorder` locks the current record, validates sequence consistency, skips unchanged update snapshots, creates the next version row, and updates the record `version_no`.
-- Do not update versioned records without considering whether a version snapshot must be created.
-- For optimistic concurrency paths, preserve `base_version_no`, `force`, and `merge` semantics and cover conflicts in request specs.
-
-## Domain cautions
-
-- Posts have tag snapshots, parent post implications, original-created ranges, viewed state, and version conflict behavior.
-- Tags have canonical names, aliases through `TagName`, categories, parent implications, discard behavior, and version snapshots.
-- Nico tags have separate relation/version behavior; do not treat them like normal editable tags without checking existing code.
-- Wiki pages involve page content, revisions/history, version rows, title/tag-name behavior, and diff/restore paths.
-- Materials, theatres, and comments have user and permission checks; inspect the controller before changing them.
-
-## API responses
-
-- Use representation classes under `app/representations` when existing endpoints do.
-- Keep response keys consistent with existing JSON contracts; frontend code expects camelCase conversion client-side, while Rails params and JSON keys are generally snake_case.
-- Preserve existing HTTP status conventions: `:unauthorized` for no user, `:forbidden` for insufficient role or banned user, `:not_found` for missing records, and `:unprocessable_entity` for validation failures.
-
-## Files to avoid in routine work
-
-- Do not inspect or edit `tmp/`, `log/`, `storage/`, `vendor/`, or dependency directories unless explicitly needed.
-- Do not modify generated schema or migration output without the corresponding migration when schema changes are made.

backend/Gemfile

@@ -46,10 +46,10 @@ group :development, :test do
 
   # Omakase Ruby styling [https://github.com/rails/rubocop-rails-omakase/]
   gem "rubocop-rails-omakase", require: false
-
-  gem 'factory_bot_rails'
 end
 
+
+
 gem "mysql2", "~> 0.5.6"
 
 gem "image_processing", "~> 1.14"
@@ -65,7 +65,3 @@ gem 'dotenv-rails'
 gem 'whenever', require: false
 
 gem 'discard'
-
-gem "rspec-rails", "~> 8.0", :groups => [:development, :test]
-
-gem 'aws-sdk-s3', require: false

backend/Gemfile.lock

@@ -73,25 +73,6 @@ GEM
       tzinfo (~> 2.0, >= 2.0.5)
       uri (>= 0.13.1)
     ast (2.4.3)
-    aws-eventstream (1.4.0)
-    aws-partitions (1.1231.0)
-    aws-sdk-core (3.244.0)
-      aws-eventstream (~> 1, >= 1.3.0)
-      aws-partitions (~> 1, >= 1.992.0)
-      aws-sigv4 (~> 1.9)
-      base64
-      bigdecimal
-      jmespath (~> 1, >= 1.6.1)
-      logger
-    aws-sdk-kms (1.123.0)
-      aws-sdk-core (~> 3, >= 3.244.0)
-      aws-sigv4 (~> 1.5)
-    aws-sdk-s3 (1.217.0)
-      aws-sdk-core (~> 3, >= 3.244.0)
-      aws-sdk-kms (~> 1)
-      aws-sigv4 (~> 1.5)
-    aws-sigv4 (1.12.1)
-      aws-eventstream (~> 1, >= 1.0.2)
     base64 (0.2.0)
     bcrypt_pbkdf (1.1.1)
     bcrypt_pbkdf (1.1.1-arm64-darwin)
@@ -118,11 +99,6 @@ GEM
     drb (2.2.1)
     ed25519 (1.4.0)
     erubi (1.13.1)
-    factory_bot (6.5.6)
-      activesupport (>= 6.1.0)
-    factory_bot_rails (6.5.1)
-      factory_bot (~> 6.5)
-      railties (>= 6.1.0)
     ffi (1.17.2-aarch64-linux-gnu)
     ffi (1.17.2-aarch64-linux-musl)
     ffi (1.17.2-arm-linux-gnu)
@@ -176,7 +152,6 @@ GEM
       pp (>= 0.6.0)
       rdoc (>= 4.0.0)
       reline (>= 0.4.2)
-    jmespath (1.6.2)
     json (2.12.0)
     jwt (2.10.1)
       base64
@@ -323,23 +298,6 @@ GEM
       io-console (~> 0.5)
     rexml (3.4.1)
     rouge (3.30.0)
-    rspec-core (3.13.6)
-      rspec-support (~> 3.13.0)
-    rspec-expectations (3.13.5)
-      diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.13.0)
-    rspec-mocks (3.13.7)
-      diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.13.0)
-    rspec-rails (8.0.2)
-      actionpack (>= 7.2)
-      activesupport (>= 7.2)
-      railties (>= 7.2)
-      rspec-core (~> 3.13)
-      rspec-expectations (~> 3.13)
-      rspec-mocks (~> 3.13)
-      rspec-support (~> 3.13)
-    rspec-support (3.13.6)
     rss (0.3.1)
       rexml
     rubocop (1.75.6)
@@ -461,13 +419,11 @@ PLATFORMS
   x86_64-linux-musl
 
 DEPENDENCIES
-  aws-sdk-s3
   bootsnap
   brakeman
   diff-lcs
   discard
   dotenv-rails
-  factory_bot_rails
   gollum
   image_processing (~> 1.14)
   jwt
@@ -477,7 +433,6 @@ DEPENDENCIES
   puma (>= 5.0)
   rack-cors
   rails (~> 8.0.2)
-  rspec-rails (~> 8.0)
   rubocop-rails-omakase
   sprockets-rails
   sqlite3 (>= 2.1)

backend/app/controllers/application_controller.rb

@@ -1,40 +1,14 @@
 class ApplicationController < ActionController::API
-  before_action :reject_banned_ip_address!
   before_action :authenticate_user
-  before_action :reject_banned_user!
 
-  def current_user = @current_user
+  def current_user
+    @current_user
+  end
 
   private
 
   def authenticate_user
     code = request.headers['X-Transfer-Code'] || request.headers['HTTP_X_TRANSFER_CODE']
-    return if code.blank?
-
     @current_user = User.find_by(inheritance_code: code)
   end
-
-  def bool? key, default: false
-    return default if params[key].nil?
-
-    s = params[key].to_s.strip.downcase
-    if default
-      !(s.in?(['0', 'false', 'off', 'no']))
-    else
-      s.in?(['', '1', 'true', 'on', 'yes'])
-    end
-  end
-
-  def reject_banned_ip_address!
-    ip_address = IpAddress.find_by(ip_address: IPAddr.new(request.remote_ip).hton)
-    return unless ip_address&.banned?
-
-    head :forbidden
-  end
-
-  def reject_banned_user!
-    return unless current_user&.banned?
-
-    head :forbidden
-  end
 end

backend/app/controllers/deerjikists_controller.rb

@@ -1,47 +0,0 @@
-class DeerjikistsController < ApplicationController
-  def show
-    platform = params[:platform].to_s.strip
-    code = params[:code].to_s.strip
-    return head :bad_request if platform.blank? || code.blank?
-
-    deerjikist = Deerjikist
-                 .joins(:tag)
-                 .includes(tag: :tag_name)
-                 .find_by(platform:, code:)
-    if deerjikist
-      render json: DeerjikistRepr.base(deerjikist)
-    else
-      head :not_found
-    end
-  end
-
-  def update
-    return head :unauthorized unless current_user
-    return head :forbidden unless current_user.gte_member?
-
-    platform = params[:platform].to_s.strip
-    code = params[:code].to_s.strip
-    tag_id = params[:tag_id].to_i
-    return head :bad_request if platform.blank? || code.blank? || tag_id <= 0
-
-    deerjikist = Deerjikist.find_or_initialize_by(platform:, code:).tap do |d|
-      d.tag_id = tag_id
-      d.save!
-    end
-
-    render json: DeerjikistRepr.base(deerjikist)
-  end
-
-  def destroy
-    return head :unauthorized unless current_user
-    return head :forbidden unless current_user.gte_member?
-
-    platform = params[:platform].to_s.strip
-    code = params[:code].to_s.strip
-    return head :bad_request if platform.blank? || code.blank?
-
-    Deerjikist.find([platform, code]).destroy!
-
-    head :no_content
-  end
-end

backend/app/controllers/ip_addresses_controller.rb

@@ -0,0 +1,20 @@
+class IpAddressesController < ApplicationController
+  def index
+    @ip_addresses = IpAddress.all
+
+    render json: @ip_addresses
+  end
+
+  def show
+    render json: @ip_address
+  end
+
+  def create
+  end
+
+  def update
+  end
+
+  def destroy
+  end
+end

backend/app/controllers/materials_controller.rb

@@ -1,101 +0,0 @@
-class MaterialsController < ApplicationController
-  def index
-    page = (params[:page].presence || 1).to_i
-    limit = (params[:limit].presence || 20).to_i
-
-    page = 1 if page < 1
-    limit = 1 if limit < 1
-
-    offset = (page - 1) * limit
-
-    tag_id = params[:tag_id].presence
-    parent_id = params[:parent_id].presence
-
-    q = Material.includes(:tag, :created_by_user).with_attached_file
-    q = q.where(tag_id:) if tag_id
-    q = q.where(parent_id:) if parent_id
-
-    count = q.count
-    materials = q.order(created_at: :desc, id: :desc).limit(limit).offset(offset)
-
-    render json: { materials: MaterialRepr.many(materials, host: request.base_url), count: count }
-  end
-
-  def show
-    material =
-        Material
-        .includes(:tag)
-        .with_attached_file
-        .find_by(id: params[:id])
-    return head :not_found unless material
-
-    wiki_page_body = material.tag.tag_name.wiki_page&.current_revision&.body
-
-    render json: MaterialRepr.base(material, host: request.base_url).merge(wiki_page_body:)
-  end
-
-  def create
-    return head :unauthorized unless current_user
-
-    tag_name_raw = params[:tag].to_s.strip
-    file = params[:file]
-    url = params[:url].to_s.strip.presence
-    return head :bad_request if tag_name_raw.blank? || (file.blank? && url.blank?)
-
-    tag_name = TagName.find_undiscard_or_create_by!(name: tag_name_raw)
-    tag = tag_name.tag
-    tag = Tag.create!(tag_name:, category: :material) unless tag
-
-    material = Material.new(tag:, url:,
-                            created_by_user: current_user,
-                            updated_by_user: current_user)
-    material.file.attach(file)
-
-    if material.save
-      render json: MaterialRepr.base(material, host: request.base_url), status: :created
-    else
-      render json: { errors: material.errors.full_messages }, status: :unprocessable_entity
-    end
-  end
-
-  def update
-    return head :unauthorized unless current_user
-    return head :forbidden unless current_user.gte_member?
-
-    material = Material.with_attached_file.find_by(id: params[:id])
-    return head :not_found unless material
-
-    tag_name_raw = params[:tag].to_s.strip
-    file = params[:file]
-    url = params[:url].to_s.strip.presence
-    return head :bad_request if tag_name_raw.blank? || (file.blank? && url.blank?)
-
-    tag_name = TagName.find_undiscard_or_create_by!(name: tag_name_raw)
-    tag = tag_name.tag
-    tag = Tag.create!(tag_name:, category: :material) unless tag
-
-    material.update!(tag:, url:, updated_by_user: current_user)
-    if file
-      material.file.attach(file)
-    else
-      material.file.purge
-    end
-
-    if material.save
-      render json: MaterialRepr.base(material, host: request.base_url)
-    else
-      render json: { errors: material.errors.full_messages }, status: :unprocessable_entity
-    end
-  end
-
-  def destroy
-    return head :unauthorized unless current_user
-    return head :forbidden unless current_user.gte_member?
-
-    material = Material.find_by(id: params[:id])
-    return head :not_found unless material
-
-    material.discard
-    head :no_content
-  end
-end

backend/app/controllers/nico_tag_relation_controller.rb

@@ -0,0 +1,16 @@
+class NicoTagRelationController < ApplicationController
+  def index
+  end
+
+  def show
+  end
+
+  def create
+  end
+
+  def update
+  end
+
+  def destroy
+  end
+end

backend/app/controllers/nico_tags_controller.rb

@@ -3,12 +3,10 @@ class NicoTagsController < ApplicationController
     limit = (params[:limit] || 20).to_i
     cursor = params[:cursor].presence
 
-    q = Tag.nico_tags
+    q = Tag.nico_tags.includes(:linked_tags).order(updated_at: :desc)
-           .includes(:tag_name, tag_name: :wiki_page, linked_tags: { tag_name: :wiki_page })
-           .order(updated_at: :desc)
     q = q.where('tags.updated_at < ?', Time.iso8601(cursor)) if cursor
 
-    tags = q.limit(limit + 1).to_a
+    tags = q.limit(limit + 1)
 
     next_cursor = nil
     if tags.size > limit
@@ -17,35 +15,27 @@ class NicoTagsController < ApplicationController
     end
 
     render json: { tags: tags.map { |tag|
-      TagRepr.base(tag).merge(linked_tags: tag.linked_tags.map { |lt|
+      tag.as_json(include: :linked_tags)
-        TagRepr.base(lt)
-      })
     }, next_cursor: }
   end
 
   def update
     return head :unauthorized unless current_user
-    return head :forbidden unless current_user.gte_member?
+    return head :forbidden unless current_user.member?
 
     id = params[:id].to_i
 
     tag = Tag.find(id)
-    return head :bad_request unless tag.nico?
+    return head :bad_request if tag.category != 'nico'
 
-    linked_tag_names = params[:tags].to_s.split
+    linked_tag_names = params[:tags].to_s.split(' ')
-    linked_tags = Tag.normalise_tags!(linked_tag_names, with_tagme: false,
+    linked_tags = Tag.normalise_tags(linked_tag_names, with_tagme: false)
-                                                        with_no_deerjikist: false)
+    return head :bad_request if linked_tags.filter { |t| t.category == 'nico' }.present?
-    return head :bad_request if linked_tags.any? { |t| t.nico? }
 
-    ApplicationRecord.transaction do
+    tag.linked_tags = linked_tags
-      TagVersioning.record_tag_snapshots!(linked_tags, created_by_user: current_user)
+    tag.updated_at = Time.now
+    tag.save!
 
-      tag.linked_tags = linked_tags
+    render json: tag.linked_tags, status: :ok
-      tag.save!
-
-      NicoTagVersionRecorder.record!(tag:, event_type: :update, created_by_user: current_user)
-    end
-
-    render json: tag.linked_tags.map { |t| TagRepr.base(t) }, status: :ok
   end
 end

backend/app/controllers/post_tags_controller.rb

@@ -0,0 +1,16 @@
+class PostTagsController < ApplicationController
+  def index
+  end
+
+  def show
+  end
+
+  def create
+  end
+
+  def update
+  end
+
+  def destroy
+  end
+end

backend/app/controllers/post_versions_controller.rb

@@ -1,119 +0,0 @@
-class PostVersionsController < ApplicationController
-  def index
-    post_id = params[:post].presence
-    tag_id = params[:tag].presence
-    page = (params[:page].presence || 1).to_i
-    limit = (params[:limit].presence || 20).to_i
-
-    page = 1 if page < 1
-    limit = 1 if limit < 1
-
-    offset = (page - 1) * limit
-
-    tag_name =
-        if tag_id
-          TagName.joins(:tag).find_by(tag: { id: tag_id })
-        end
-    return render json: { versions: [], count: 0 } if tag_id && tag_name.blank?
-
-    q = PostVersion.joins(<<~SQL.squish)
-          LEFT JOIN
-            post_versions prev
-            ON
-              prev.post_id = post_versions.post_id
-              AND prev.version_no = post_versions.version_no - 1
-        SQL
-        .select('post_versions.*', 'prev.title AS prev_title', 'prev.url AS prev_url',
-                'prev.thumbnail_base AS prev_thumbnail_base', 'prev.tags AS prev_tags',
-                'prev.original_created_from AS prev_original_created_from',
-                'prev.original_created_before AS prev_original_created_before')
-    q = q.where('post_versions.post_id = ?', post_id) if post_id
-    if tag_name
-      escaped = ActiveRecord::Base.sanitize_sql_like(tag_name.name)
-      q = q.where(("CONCAT(' ', post_versions.tags, ' ') LIKE :kw " +
-                   "OR CONCAT(' ', prev.tags, ' ') LIKE :kw"),
-                  kw: "% #{ escaped } %")
-    end
-
-    count = q.except(:select, :order, :limit, :offset).count
-
-    versions = q.order(Arel.sql('post_versions.created_at DESC, post_versions.id DESC'))
-                .limit(limit)
-                .offset(offset)
-
-    render json: { versions: serialise_versions(versions), count: }
-  end
-
-  private
-
-  def serialise_versions rows
-    user_ids = rows.map(&:created_by_user_id).compact.uniq
-    users_by_id = User.where(id: user_ids).pluck(:id, :name).to_h
-
-    rows.map do |row|
-      cur_tags = split_tags(row.tags)
-      prev_tags = split_tags(row.attributes['prev_tags'])
-
-      {
-        post_id: row.post_id,
-        version_no: row.version_no,
-        event_type: row.event_type,
-        title: {
-          current: row.title,
-          prev: row.attributes['prev_title']
-        },
-        url: {
-          current: row.url,
-          prev: row.attributes['prev_url']
-        },
-        thumbnail: {
-          current: nil,
-          prev: nil
-        },
-        thumbnail_base: {
-          current: row.thumbnail_base,
-          prev: row.attributes['prev_thumbnail_base']
-        },
-        tags: build_version_tags(cur_tags, prev_tags),
-        original_created_from: {
-          current: row.original_created_from&.iso8601,
-          prev: row.attributes['prev_original_created_from']&.iso8601
-        },
-        original_created_before: {
-          current: row.original_created_before&.iso8601,
-          prev: row.attributes['prev_original_created_before']&.iso8601
-        },
-        created_at: row.created_at.iso8601,
-        created_by_user:
-          if row.created_by_user_id
-            {
-              id: row.created_by_user_id,
-              name: users_by_id[row.created_by_user_id]
-            }
-          end
-      }
-    end
-  end
-
-  def build_version_tags(cur_tags, prev_tags)
-    (cur_tags | prev_tags).map do |name|
-      type =
-        if cur_tags.include?(name) && prev_tags.include?(name)
-          'context'
-        elsif cur_tags.include?(name)
-          'added'
-        else
-          'removed'
-        end
-
-      {
-        name:,
-        type:
-      }
-    end
-  end
-
-  def split_tags(tags)
-    tags.to_s.split(/\s+/).reject(&:blank?)
-  end
-end

backend/app/controllers/posts_controller.rb

@@ -1,89 +1,42 @@
 class PostsController < ApplicationController
   Event = Struct.new(:post, :tag, :user, :change_type, :timestamp, keyword_init: true)
 
+  # GET /posts
   def index
-    url = params[:url].presence
-    title = params[:title].presence
-    original_created_from = params[:original_created_from].presence
-    original_created_to = params[:original_created_to].presence
-    created_between = params[:created_from].presence, params[:created_to].presence
-    updated_between = params[:updated_from].presence, params[:updated_to].presence
-
-    order = params[:order].to_s.split(':', 2).map(&:strip)
-    unless order[0].in?(['title', 'url', 'original_created_at', 'created_at', 'updated_at'])
-      order[0] = 'original_created_at'
-    end
-    unless order[1].in?(['asc', 'desc'])
-      order[1] =
-          if order[0].in?(['title', 'url'])
-            'asc'
-          else
-            'desc'
-          end
-    end
-
     page = (params[:page].presence || 1).to_i
     limit = (params[:limit].presence || 20).to_i
+    cursor = params[:cursor].presence
 
     page = 1 if page < 1
     limit = 1 if limit < 1
 
     offset = (page - 1) * limit
 
-    pt_max_sql =
+    sort_sql =
-        PostTag
+        'COALESCE(posts.original_created_before - INTERVAL 1 SECOND,' +
-        .select('post_id, MAX(updated_at) AS max_updated_at')
+        'posts.original_created_from,' +
-        .group('post_id')
+        'posts.created_at)'
-        .to_sql
-
-    updated_at_all_sql =
-        'GREATEST(posts.updated_at,' +
-        'COALESCE(pt_max.max_updated_at, posts.updated_at))'
-
     q =
         filtered_posts
-        .joins("LEFT JOIN (#{ pt_max_sql }) pt_max ON pt_max.post_id = posts.id")
+        .preload(:tags)
-        .reselect('posts.*', Arel.sql("#{ updated_at_all_sql } AS updated_at_all"))
-        .preload(tags: [:deerjikists, :materials, { tag_name: :wiki_page }])
         .with_attached_thumbnail
-
+        .select("posts.*, #{ sort_sql } AS sort_ts")
-    q = q.where('posts.url LIKE ?', "%#{ url }%") if url
+        .order(Arel.sql("#{ sort_sql } DESC"))
-    q = q.where('posts.title LIKE ?', "%#{ title }%") if title
+    posts = (
-    if original_created_from
+        if cursor
-      q = q.where('posts.original_created_before > ?', original_created_from)
+          q.where("#{ sort_sql } < ?", Time.iso8601(cursor)).limit(limit + 1)
-    end
-    if original_created_to
-      q = q.where('posts.original_created_from <= ?', original_created_to)
-    end
-    q = q.where('posts.created_at >= ?', created_between[0]) if created_between[0]
-    q = q.where('posts.created_at <= ?', created_between[1]) if created_between[1]
-    if updated_between[0]
-      q = q.where("#{ updated_at_all_sql } >= ?", updated_between[0])
-    end
-    if updated_between[1]
-      q = q.where("#{ updated_at_all_sql } <= ?", updated_between[1])
-    end
-
-    sort_sql =
-        case order[0]
-        when 'original_created_at'
-          'COALESCE(posts.original_created_before - INTERVAL 1 MINUTE,' +
-          'posts.original_created_from,' +
-          'posts.created_at) '
-        when 'updated_at'
-          updated_at_all_sql
         else
-          "posts.#{ order[0] }"
+          q.limit(limit).offset(offset)
-        end
+        end).to_a
-    posts = q.order(Arel.sql("#{ sort_sql } #{ order[1] }, posts.id #{ order[1] }"))
-             .limit(limit)
-             .offset(offset)
-             .to_a
 
-    q = q.except(:select, :order)
+    next_cursor = nil
+    if cursor && posts.length > limit
+      next_cursor = posts.last.read_attribute('sort_ts').iso8601(6)
+      posts = posts.first(limit)
+    end
 
     render json: { posts: posts.map { |post|
-      PostRepr.base(post).merge(updated_at: post.updated_at_all).tap do |json|
+      post.as_json(include: { tags: { only: [:id, :name, :category, :post_count] } }).tap do |json|
         json['thumbnail'] =
             if post.thumbnail.attached?
               rails_storage_proxy_url(post.thumbnail, only_path: false)
@@ -91,68 +44,63 @@ class PostsController < ApplicationController
               nil
             end
       end
-    }, count: q.group_values.present? ? q.count.size : q.count }
+    }, count: filtered_posts.count(:id), next_cursor: }
   end
 
   def random
-    post = filtered_posts.preload(tags: [:deerjikists, :materials, { tag_name: :wiki_page }])
+    post = filtered_posts.order('RAND()').first
-                         .order('RAND()')
-                         .first
     return head :not_found unless post
 
-    render json: PostRepr.base(post, current_user)
+    viewed = current_user&.viewed?(post) || false
+
+    render json: (post
+                  .as_json(include: { tags: { only: [:id, :name, :category, :post_count] } })
+                  .merge(viewed:))
   end
 
+  # GET /posts/1
   def show
-    post = Post.includes(tags: [:deerjikists, :materials, { tag_name: :wiki_page }]).find_by(id: params[:id])
+    post = Post.includes(:tags).find(params[:id])
     return head :not_found unless post
 
-    render json: PostRepr.base(post, current_user)
+    viewed = current_user&.viewed?(post) || false
-                         .merge(tags: build_tag_tree_for(post.tags),
+
-                                related: PostRepr.many(post.related(limit: 20)))
+    json = post.as_json
+    json['tags'] = build_tag_tree_for(post.tags)
+    json['related'] = post.related(limit: 20)
+    json['viewed'] = viewed
+
+    render json:
   end
 
+  # POST /posts
   def create
     return head :unauthorized unless current_user
-    return head :forbidden unless current_user.gte_member?
+    return head :forbidden unless current_user.member?
 
+    # TODO: URL が正規のものがチェック，不正ならエラー
+    # TODO: URL は必須にする（タイトルは省略可）．
     # TODO: サイトに応じて thumbnail_base 設定
-    title = params[:title].presence
+    title = params[:title]
     url = params[:url]
     thumbnail = params[:thumbnail]
-    tag_names = params[:tags].to_s.split
+    tag_names = params[:tags].to_s.split(' ')
     original_created_from = params[:original_created_from]
     original_created_before = params[:original_created_before]
-    parent_post_ids = parse_parent_post_ids
 
-    post = Post.new(title:, url:, thumbnail_base: nil, uploaded_user: current_user,
+    post = Post.new(title:, url:, thumbnail_base: '', uploaded_user: current_user,
                     original_created_from:, original_created_before:)
-    post.thumbnail.attach(thumbnail) if thumbnail.present?
+    post.thumbnail.attach(thumbnail)
-
+    if post.save
-    ApplicationRecord.transaction do
+      post.resized_thumbnail!
-      post.save!
+      tags = Tag.normalise_tags(tag_names)
-
-      tags = Tag.normalise_tags!(tag_names)
-      TagVersioning.record_tag_snapshots!(tags, created_by_user: current_user)
-
       tags = Tag.expand_parent_tags(tags)
       sync_post_tags!(post, tags)
-
+      render json: post.as_json(include: { tags: { only: [:id, :name, :category, :post_count] } }),
-      sync_parent_posts!(post, parent_post_ids)
+             status: :created
-
+    else
-      post.resized_thumbnail!
+      render json: { errors: post.errors.full_messages }, status: :unprocessable_entity
-
-      PostVersionRecorder.record!(post:, event_type: :create, created_by_user: current_user)
     end
-
-    post.reload
-    render json: PostRepr.base(post), status: :created
-  rescue Tag::NicoTagNormalisationError
-    head :bad_request
-  rescue ArgumentError => e
-    render json: { errors: [e.message] }, status: :unprocessable_entity
-  rescue ActiveRecord::RecordInvalid => e
-    render json: { errors: e.record.errors.full_messages }, status: :unprocessable_entity
   end
 
   def viewed
@@ -169,85 +117,36 @@ class PostsController < ApplicationController
     head :no_content
   end
 
+  # PATCH/PUT /posts/1
   def update
     return head :unauthorized unless current_user
-    return head :forbidden unless current_user.gte_member?
+    return head :forbidden unless current_user.member?
 
-    force = bool?(:force)
+    title = params[:title]
-    merge = bool?(:merge)
+    tag_names = params[:tags].to_s.split(' ')
-    return head :bad_request if force && merge
-
-    base_version_no = parse_base_version_no
-    return head :bad_request if !(force) && !(base_version_no)
-
-    title = params[:title].presence
-    tag_names = params[:tags].to_s.split
     original_created_from = params[:original_created_from]
     original_created_before = params[:original_created_before]
-    parent_post_ids = parse_parent_post_ids
 
-    post = nil
+    post = Post.find(params[:id].to_i)
-    conflict_json = nil
+    if post.update(title:, original_created_from:, original_created_before:)
-
+      tags = post.tags.where(category: 'nico').to_a +
-    ApplicationRecord.transaction do
+             Tag.normalise_tags(tag_names, with_tagme: false)
-      post = Post.lock.find(params[:id].to_i)
+      tags = Tag.expand_parent_tags(tags)
-
+      sync_post_tags!(post, tags)
-      base_version = nil
+      json = post.as_json
-      base_snapshot = nil
+      json['tags'] = build_tag_tree_for(post.tags)
-      current_snapshot = nil
+      render json:, status: :ok
-      unless force
+    else
-        base_version = post.post_versions.find_by!(version_no: base_version_no)
+      render json: post.errors, status: :unprocessable_entity
-
-        base_snapshot = post_snapshot_from_version(base_version)
-        current_snapshot = post_snapshot_from_record(post)
-      end
-      incoming_snapshot = post_incoming_snapshot(title:,
-                                                 original_created_from:,
-                                                 original_created_before:,
-                                                 tag_names:,
-                                                 parent_post_ids:)
-
-      snapshot_to_apply =
-          if force || post.version_no == base_version_no || current_snapshot == base_snapshot
-            incoming_snapshot
-          else
-            changes = post_snapshot_changes(base_snapshot, current_snapshot, incoming_snapshot)
-            conflicts = changes.select { |change| change[:conflict] }
-
-            if merge && conflicts.empty?
-              merge_post_snapshots(base_snapshot, current_snapshot, incoming_snapshot)
-            else
-              conflict_json = post_conflict_json(post:,
-                                                 base_version_no:,
-                                                 base_snapshot:,
-                                                 current_snapshot:,
-                                                 incoming_snapshot:,
-                                                 changes:,
-                                                 conflicts:)
-              raise ActiveRecord::Rollback
-            end
-          end
-
-      apply_post_snapshot!(post, snapshot_to_apply)
     end
+  end
 
-    return render json: conflict_json, status: :conflict if conflict_json
+  # DELETE /posts/1
-
+  def destroy
-    post.reload
-    json = PostRepr.base(post, current_user)
-    json['tags'] = build_tag_tree_for(post.tags)
-    render json:, status: :ok
-  rescue Tag::NicoTagNormalisationError
-    head :bad_request
-  rescue ArgumentError => e
-    render json: { errors: [e.message] }, status: :unprocessable_entity
-  rescue ActiveRecord::RecordInvalid => e
-    render json: { errors: e.record.errors.full_messages }, status: :unprocessable_entity
   end
 
   def changes
-    id = params[:id].presence
+    id = params[:id]
-    tag_id = params[:tag].presence
     page = (params[:page].presence || 1).to_i
     limit = (params[:limit].presence || 20).to_i
 
@@ -258,41 +157,36 @@ class PostsController < ApplicationController
 
     pts = PostTag.with_discarded
     pts = pts.where(post_id: id) if id.present?
-    pts = pts.where(tag_id:) if tag_id.present?
+    pts = pts.includes(:post, :tag, :created_user, :deleted_user)
-    pts = pts.includes(:post, :created_user, :deleted_user,
-                       tag: [:deerjikists, :materials, { tag_name: :wiki_page }])
 
     events = []
     pts.each do |pt|
-      tag = TagRepr.base(pt.tag)
-      post = pt.post
-
       events << Event.new(
-          post:,
+          post:         pt.post,
-          tag:,
+          tag:          pt.tag,
-          user: pt.created_user && { id: pt.created_user.id, name: pt.created_user.name },
+          user:         pt.created_user && { id: pt.created_user.id, name: pt.created_user.name },
-          change_type: 'add',
+          change_type:  'add',
-          timestamp: pt.created_at)
+          timestamp:    pt.created_at)
 
       if pt.discarded_at
         events << Event.new(
-            post:,
+            post:         pt.post,
-            tag:,
+            tag:          pt.tag,
-            user: pt.deleted_user && { id: pt.deleted_user.id, name: pt.deleted_user.name },
+            user:         pt.deleted_user && { id: pt.deleted_user.id, name: pt.deleted_user.name },
-            change_type: 'remove',
+            change_type:  'remove',
-            timestamp: pt.discarded_at)
+            timestamp:    pt.discarded_at)
       end
     end
     events.sort_by!(&:timestamp)
     events.reverse!
 
-    render json: { changes: (events.slice(offset, limit) || []).as_json, count: events.size }
+    render json: { changes: events.slice(offset, limit).as_json, count: events.size }
   end
 
   private
 
   def filtered_posts
-    tag_names = params[:tags].to_s.split
+    tag_names = params[:tags]&.split(' ')
     match_type = params[:match]
     if tag_names.present?
       filter_posts_by_tags(tag_names, match_type)
@@ -302,41 +196,17 @@ class PostsController < ApplicationController
   end
 
   def filter_posts_by_tags tag_names, match_type
-    literals = tag_names.map do |raw_name|
+    posts = Post.joins(:tags)
-      { name: TagName.canonicalise(raw_name.sub(/\Anot:/i, '')).first,
-        negative: raw_name.downcase.start_with?('not:') }
-    end
-
-    return Post.all if literals.empty?
-
     if match_type == 'any'
-      literals.reduce(Post.none) do |posts, literal|
+      posts = posts.where(tags: { name: tag_names }).distinct
-        posts.or(tag_literal_relation(literal[:name], negative: literal[:negative]))
-      end
     else
-      literals.reduce(Post.all) do |posts, literal|
+      tag_names.each do |tag|
-        ids = tagged_post_ids_for(literal[:name])
+        posts = posts.where(id: Post.joins(:tags).where(tags: { name: tag }))
-        if literal[:negative]
-          posts.where.not(id: ids)
-        else
-          posts.where(id: ids)
-        end
       end
     end
+    posts.distinct
   end
 
-  def tag_literal_relation name, negative:
-    ids = tagged_post_ids_for(name)
-    if negative
-      Post.where.not(id: ids)
-    else
-      Post.where(id: ids)
-    end
-  end
-
-  def tagged_post_ids_for(name) =
-      Post.joins(tags: :tag_name).where(tag_names: { name: }).select(:id)
-
   def sync_post_tags! post, desired_tags
     desired_tags.each do |t|
       t.save! if t.new_record?
@@ -385,7 +255,7 @@ class PostsController < ApplicationController
       return nil unless tag
 
       if path.include?(tag_id)
-        return TagRepr.base(tag).merge(children: [])
+        return tag.as_json(only: [:id, :name, :category, :post_count]).merge(children: [])
       end
 
       if memo.key?(tag_id)
@@ -397,247 +267,9 @@ class PostsController < ApplicationController
 
       children = child_ids.filter_map { |cid| build_node.(cid, new_path) }
 
-      memo[tag_id] = TagRepr.base(tag).merge(children:)
+      memo[tag_id] = tag.as_json(only: [:id, :name, :category, :post_count]).merge(children:)
     end
 
     root_ids.filter_map { |id| build_node.call(id, []) }
   end
-
-  def parse_parent_post_ids
-    raise ArgumentError, 'parent_post_ids は必須です．' unless params.key?(:parent_post_ids)
-
-    params[:parent_post_ids].to_s.split.map { |token|
-      id = Integer(token, exception: false)
-      raise ArgumentError, "親投稿 Id. が不正です: #{ token }" if id.nil? || id <= 0
-
-      id
-    }.uniq
-  end
-
-  def sync_parent_posts! post, parent_post_ids
-    if parent_post_ids.include?(post.id)
-      post.errors.add(:base, '自分自身を親投稿にはできません．')
-      raise ActiveRecord::RecordInvalid, post
-    end
-
-    existing_ids = Post.where(id: parent_post_ids).pluck(:id)
-    missing_ids = parent_post_ids - existing_ids
-
-    if missing_ids.present?
-      post.errors.add(:base, "存在しない親投稿 ID があります: #{ missing_ids.join(' ') }")
-      raise ActiveRecord::RecordInvalid, post
-    end
-
-    current_ids = post.parent_posts.pluck(:id)
-
-    ids_to_add = parent_post_ids - current_ids
-    ids_to_remove = current_ids - parent_post_ids
-
-    PostImplication.where(post_id: post.id, parent_post_id: ids_to_remove).delete_all
-
-    ids_to_add.each do |parent_post_id|
-      PostImplication.create_or_find_by!(post_id: post.id, parent_post_id:)
-    end
-  end
-
-  def parse_base_version_no
-    version_no = Integer(params[:base_version_no], exception: false)
-    if version_no&.positive?
-      version_no
-    else
-      nil
-    end
-  end
-
-  def post_snapshot_from_version version
-    { title: version.title,
-      original_created_from: snapshot_time(version.original_created_from),
-      original_created_before: snapshot_time(version.original_created_before),
-      tag_names: editable_tag_names_from_version(version),
-      parent_post_ids: snapshot_parent_post_ids_from_version(version) }
-  end
-
-  def editable_tag_names_from_version version
-    version.tags.to_s.split.reject { |name| name.downcase.start_with?('nico:') }.sort
-  end
-
-  def post_snapshot_from_record post
-    { title: post.title,
-      original_created_from: snapshot_time(post.original_created_from),
-      original_created_before: snapshot_time(post.original_created_before),
-      tag_names: editable_tag_names_from_post(post),
-      parent_post_ids: post.parent_posts.order(:id).pluck(:id) }
-  end
-
-  def editable_tag_names_from_post post
-    post.tags.not_nico.joins(:tag_name).order('tag_names.name').pluck('tag_names.name')
-  end
-
-  def post_incoming_snapshot title:, original_created_from:, original_created_before:,
-                             tag_names:, parent_post_ids:
-    { title:,
-      original_created_from: snapshot_time(original_created_from),
-      original_created_before: snapshot_time(original_created_before),
-      tag_names: incoming_tag_names_for_snapshot(tag_names),
-      parent_post_ids: parent_post_ids.sort }
-  end
-
-  def snapshot_parent_post_ids_from_version version
-    if version.respond_to?(:parent_post_ids)
-      version.parent_post_ids.to_s.split.map { |id| id.to_i }.sort
-    elsif version.respond_to?(:parent_id) && version.parent_id
-      [version.parent_id]
-    else
-      []
-    end
-  end
-
-  def snapshot_time value
-    return nil if value.blank?
-
-    value = Time.zone.parse(value.to_s) if value in String
-    value&.in_time_zone&.iso8601(6)
-  rescue ArgumentError, TypeError
-    value.to_s
-  end
-
-  def incoming_tag_names_for_snapshot raw_tag_names
-    tags = Tag.normalise_tags!(raw_tag_names, with_tagme: false)
-
-    Tag.expand_parent_tags(tags).map(&:name).uniq.sort
-  end
-
-  def post_conflict_json post:, base_version_no:, base_snapshot:,
-                         current_snapshot:, incoming_snapshot:, changes:, conflicts:
-    { error: 'conflict',
-      message: '競合が発生しました．',
-      post_id: post.id,
-      base_version_no:,
-      current_version_no: post.version_no,
-      base: base_snapshot,
-      current: current_snapshot,
-      mine: incoming_snapshot,
-      changes:,
-      conflicts:,
-      mergeable: conflicts.empty? }
-  end
-
-  def post_snapshot_changes base_snapshot, current_snapshot, incoming_snapshot
-    [scalar_snapshot_change(:title, 'タイトル',
-                            base_snapshot, current_snapshot, incoming_snapshot),
-     scalar_snapshot_change(:original_created_from, 'オリジナルの作成日時（以降）',
-                            base_snapshot, current_snapshot, incoming_snapshot),
-     scalar_snapshot_change(:original_created_before, 'オリジナルの作成日時（より前）',
-                            base_snapshot, current_snapshot, incoming_snapshot),
-     set_snapshot_change(:tag_names, 'タグ',
-                         base_snapshot, current_snapshot, incoming_snapshot),
-     set_snapshot_change(:parent_post_ids, '親投稿',
-                         base_snapshot, current_snapshot, incoming_snapshot)].compact
-  end
-
-  def scalar_snapshot_change field, label, base_snapshot, current_snapshot, incoming_snapshot
-    base = base_snapshot[field]
-    current = current_snapshot[field]
-    mine = incoming_snapshot[field]
-
-    return nil if current == base && mine == base
-
-    { field:, label:, base:, current:, mine:,
-      changed_by_current: current != base,
-      changed_by_me: mine != base,
-      conflict: scalar_snapshot_conflict?(base, current, mine) }
-  end
-
-  def scalar_snapshot_conflict? base, current, mine
-    current != base && mine != base && current != mine
-  end
-
-  def set_snapshot_change field, label, base_snapshot, current_snapshot, incoming_snapshot
-    base = base_snapshot[field].to_a
-    current = current_snapshot[field].to_a
-    mine = incoming_snapshot[field].to_a
-
-    added_by_current = current - base
-    removed_by_current = base - current
-    added_by_me = mine - base
-    removed_by_me = base - mine
-
-    if (added_by_current.empty? &&
-        removed_by_current.empty? &&
-        added_by_me.empty? &&
-        removed_by_me.empty?)
-      return nil
-    end
-
-    { field:, label:, base:, current:, mine:, added_by_current:, removed_by_current:,
-      added_by_me:, removed_by_me:,
-      changed_by_current: added_by_current.present? || removed_by_current.present?,
-      changed_by_me: added_by_me.present? || removed_by_me.present?,
-      conflict: set_snapshot_conflict?(added_by_current:,
-                                       removed_by_current:,
-                                       added_by_me:,
-                                       removed_by_me:) }
-  end
-
-  def set_snapshot_conflict? added_by_current:, removed_by_current:,
-                             added_by_me:, removed_by_me:
-    (added_by_current & removed_by_me).present? || (removed_by_current & added_by_me).present?
-  end
-
-  def apply_post_snapshot! post, snapshot
-    PostVersionRecorder.ensure_snapshot!(post, created_by_user: current_user)
-
-    post.update!(title: snapshot[:title],
-                 original_created_from: snapshot[:original_created_from],
-                 original_created_before: snapshot[:original_created_before])
-
-    editable_tags = Tag.normalise_tags!(snapshot[:tag_names], with_tagme: false)
-    TagVersioning.record_tag_snapshots!(editable_tags, created_by_user: current_user)
-
-    readonly_tags = post.tags.nico.to_a
-
-    tags = readonly_tags + editable_tags
-    tags = Tag.expand_parent_tags(tags)
-
-    sync_post_tags!(post, tags)
-    sync_parent_posts!(post, snapshot[:parent_post_ids])
-
-    PostVersionRecorder.record!(post:, event_type: :update, created_by_user: current_user)
-  end
-
-  def merge_post_snapshots base_snapshot, current_snapshot, incoming_snapshot
-    [:title, :original_created_from, :original_created_before].map {
-      [_1, merge_scalar_snapshot_value(base_snapshot[_1],
-                                       current_snapshot[_1],
-                                       incoming_snapshot[_1])]
-    }.to_h.merge([:tag_names, :parent_post_ids].map {
-      [_1, merge_set_snapshot_value(base_snapshot[_1],
-                                    current_snapshot[_1],
-                                    incoming_snapshot[_1])]
-    }.to_h)
-  end
-
-  def merge_scalar_snapshot_value base, current, mine
-    return mine if current == base
-    return current if mine == base || current == mine
-
-    raise ArgumentError, '競合してゐる項目はマージできません．'
-  end
-
-  def merge_set_snapshot_value base, current, mine
-    base = base.to_a
-    current = current.to_a
-    mine = mine.to_a
-
-    added_by_current = current - base
-    removed_by_current = base - current
-    added_by_me = mine - base
-    removed_by_me = base - mine
-
-    merged = base + added_by_current + added_by_me
-    merged -= removed_by_current
-    merged -= removed_by_me
-
-    merged.uniq.sort
-  end
 end

backend/app/controllers/settings_controller.rb

@@ -0,0 +1,16 @@
+class SettingsController < ApplicationController
+  def index
+  end
+
+  def show
+  end
+
+  def create
+  end
+
+  def update
+  end
+
+  def destroy
+  end
+end

backend/app/controllers/tag_aliases_controller.rb

@@ -0,0 +1,16 @@
+class TagAliasesController < ApplicationController
+  def index
+  end
+
+  def show
+  end
+
+  def create
+  end
+
+  def update
+  end
+
+  def destroy
+  end
+end

backend/app/controllers/tag_children_controller.rb

@@ -1,45 +0,0 @@
-class TagChildrenController < ApplicationController
-  def create
-    return head :unauthorized unless current_user
-    return head :forbidden unless current_user.admin?
-
-    parent_id = params[:parent_id]
-    child_id = params[:child_id]
-    return head :bad_request if parent_id.blank? || child_id.blank?
-
-    parent = Tag.find(parent_id)
-    child = Tag.find(child_id)
-    return head :bad_request if parent.nico? || child.nico?
-
-    ApplicationRecord.transaction do
-      TagVersioning.ensure_snapshot!(child, created_by_user: current_user)
-
-      TagImplication.find_or_create_by!(parent_tag: parent, tag: child)
-      TagVersionRecorder.record!(tag: child, event_type: :update, created_by_user: current_user)
-    end
-
-    head :no_content
-  end
-
-  def destroy
-    return head :unauthorized unless current_user
-    return head :forbidden unless current_user.admin?
-
-    parent_id = params[:parent_id]
-    child_id = params[:child_id]
-    return head :bad_request if parent_id.blank? || child_id.blank?
-
-    parent = Tag.find(parent_id)
-    child = Tag.find(child_id)
-    return head :bad_request if parent.nico? || child.nico?
-
-    ApplicationRecord.transaction do
-      TagVersioning.ensure_snapshot!(child, created_by_user: current_user)
-
-      TagImplication.find_by(parent_tag: parent, tag: child)&.destroy!
-      TagVersionRecorder.record!(tag: child, event_type: :update, created_by_user: current_user)
-    end
-
-    head :no_content
-  end
-end

backend/app/controllers/tag_versions_controller.rb

@@ -1,92 +0,0 @@
-class TagVersionsController < ApplicationController
-  def index
-    tag_id = params[:id].presence
-    page = (params[:page].presence || 1).to_i
-    limit = (params[:limit].presence || 20).to_i
-
-    page = 1 if page < 1
-    limit = 1 if limit < 1
-
-    offset = (page - 1) * limit
-
-    q = TagVersion.joins(<<~SQL.squish)
-          LEFT JOIN
-            tag_versions prev
-            ON
-              prev.tag_id = tag_versions.tag_id
-              AND prev.version_no = tag_versions.version_no - 1
-        SQL
-      .select('tag_versions.*', 'prev.name AS prev_name', 'prev.category AS prev_category',
-              'prev.aliases AS prev_aliases', 'prev.parent_tag_ids AS prev_parent_tag_ids')
-    q = q.where('tag_versions.tag_id = ?', tag_id) if tag_id
-
-    count = q.except(:select, :order, :limit, :offset).count
-
-    versions = q.order(Arel.sql('tag_versions.created_at DESC, tag_versions.id DESC'))
-                .limit(limit)
-                .offset(offset)
-
-    render json: { versions: serialise_versions(versions), count: }
-  end
-
-  private
-
-  def serialise_versions rows
-    user_ids = rows.map(&:created_by_user_id).compact.uniq
-    users_by_id = User.where(id: user_ids).pluck(:id, :name).to_h
-
-    rows.map do |row|
-      cur_aliases = split_values(row.aliases)
-      prev_aliases = split_values(row.attributes['prev_aliases'])
-
-      cur_parent_tag_ids = split_parent_tag_ids(row.parent_tag_ids)
-      prev_parent_tag_ids = split_parent_tag_ids(row.attributes['prev_parent_tag_ids'])
-
-      all_parent_tag_ids = (cur_parent_tag_ids | prev_parent_tag_ids)
-
-      tags_by_id =
-          Tag
-          .includes(:tag_name, :materials, { tag_name: :wiki_page })
-          .where(id: all_parent_tag_ids)
-          .index_by(&:id)
-
-      parent_tags =
-          build_version_values(cur_parent_tag_ids, prev_parent_tag_ids, key: :tag_id)
-          .map do |h|
-            { tag: TagRepr.base(tags_by_id[h[:tag_id]]),
-              type: h[:type] }
-          end
-
-      { tag_id: row.tag_id,
-        version_no: row.version_no,
-        event_type: row.event_type,
-        name: { current: row.name, prev: row.attributes['prev_name'] },
-        category: { current: row.category, prev: row.attributes['prev_category'] },
-        aliases: build_version_values(cur_aliases, prev_aliases, key: :name),
-        parent_tags:,
-        created_at: row.created_at.iso8601,
-        created_by_user: row.created_by_user_id &&
-                         { id: row.created_by_user_id,
-                           name: users_by_id[row.created_by_user_id] } }
-    end
-  end
-
-  def build_version_values cur_values, prev_values, key:
-    (cur_values | prev_values).map do |value|
-      type =
-          if cur_values.include?(value) && prev_values.include?(value)
-            'context'
-          elsif cur_values.include?(value)
-            'added'
-          else
-            'removed'
-          end
-
-      { key => value, type: }
-    end
-  end
-
-  def split_values(values) = values.to_s.split(/\s+/).reject(&:blank?)
-
-  def split_parent_tag_ids(values) = split_values(values).map(&:to_i)
-end

backend/app/controllers/tags_controller.rb

@@ -1,440 +1,46 @@
-require 'net/http'
-require 'uri'
-
-
 class TagsController < ApplicationController
   def index
     post_id = params[:post]
-
+    tags = if post_id.present?
-    name = params[:name].presence
+             Tag.joins(:posts).where(posts: { id: post_id })
-    category = params[:category].presence
+           else
-    post_count_between = (params[:post_count_gte].presence || -1).to_i,
+             Tag.all
-                         (params[:post_count_lte].presence || -1).to_i
+           end
-    post_count_between[0] = nil if post_count_between[0] < 0
+    render json: tags
-    post_count_between[1] = nil if post_count_between[1] < 0
-    created_between = params[:created_from].presence, params[:created_to].presence
-    updated_between = params[:updated_from].presence, params[:updated_to].presence
-
-    order = params[:order].to_s.split(':', 2).map(&:strip)
-    unless order[0].in?(['name', 'category', 'post_count', 'created_at', 'updated_at'])
-      order[0] = 'post_count'
-    end
-    unless order[1].in?(['asc', 'desc'])
-      order[1] = order[0].in?(['name', 'category']) ? 'asc' : 'desc'
-    end
-
-    page = (params[:page].presence || 1).to_i
-    limit = (params[:limit].presence || 20).to_i
-
-    page = 1 if page < 1
-    limit = 1 if limit < 1
-
-    offset = (page - 1) * limit
-
-    q =
-        if post_id.present?
-          Tag.joins(:posts, :tag_name)
-        else
-          Tag.joins(:tag_name)
-        end
-        .includes(:tag_name, :materials, tag_name: :wiki_page)
-    q = q.where(posts: { id: post_id }) if post_id.present?
-
-    q = q.where('tag_names.name LIKE ?', "%#{ name }%") if name
-    q = q.where(category:) if category
-    q = q.where('tags.post_count >= ?', post_count_between[0]) if post_count_between[0]
-    q = q.where('tags.post_count <= ?', post_count_between[1]) if post_count_between[1]
-    q = q.where('tags.created_at >= ?', created_between[0]) if created_between[0]
-    q = q.where('tags.created_at <= ?', created_between[1]) if created_between[1]
-    q = q.where('tags.updated_at >= ?', updated_between[0]) if updated_between[0]
-    q = q.where('tags.updated_at <= ?', updated_between[1]) if updated_between[1]
-
-    sort_sql =
-        case order[0]
-        when 'name'
-          'tag_names.name'
-        when 'category'
-          'CASE tags.category ' +
-          "WHEN 'deerjikist' THEN 0 " +
-          "WHEN 'meme' THEN 1 " +
-          "WHEN 'character' THEN 2 " +
-          "WHEN 'general' THEN 3 " +
-          "WHEN 'material' THEN 4 " +
-          "WHEN 'meta' THEN 5 " +
-          "WHEN 'nico' THEN 6 END"
-        else
-          "tags.#{ order[0] }"
-        end
-    tags = q.order(Arel.sql("#{ sort_sql } #{ order[1] }, tags.id #{ order[1] }"))
-            .limit(limit)
-            .offset(offset)
-            .to_a
-
-    render json: { tags: TagRepr.many(tags), count: q.size }
-  end
-
-  def with_depth
-    parent_tag_id = params[:parent].to_i
-    parent_tag_id = nil if parent_tag_id <= 0
-
-    tag_ids =
-        if parent_tag_id
-          TagImplication.where(parent_tag_id:).select(:tag_id)
-        else
-          Tag.where.not(id: TagImplication.select(:tag_id)).select(:id)
-        end
-
-    tags =
-        Tag
-        .joins(:tag_name)
-        .includes(:tag_name, :materials, tag_name: :wiki_page)
-        .where(category: [:meme, :character, :material])
-        .where(id: tag_ids)
-        .order('tag_names.name')
-        .distinct
-        .to_a
-
-    has_children_tag_ids =
-        if tags.empty?
-          []
-        else
-          TagImplication
-              .joins(:tag)
-              .where(parent_tag_id: tags.map(&:id),
-                     tags: { category: [:meme, :character, :material] })
-              .distinct
-              .pluck(:parent_tag_id)
-        end
-
-    render json: tags.map { |tag|
-      TagRepr.base(tag).merge(has_children: has_children_tag_ids.include?(tag.id), children: [])
-    }
   end
 
   def autocomplete
-    q = params[:q].to_s.strip.sub(/\Anot:/i, '')
+    q = params[:q].to_s.strip
+    return render json: [] if q.blank?
 
-    with_nico = bool?(:nico, default: true)
+    tags = (Tag
-    present_only = bool?(:present, default: true)
+            .where('(category = ? AND name LIKE ?) OR name LIKE ?',
-
+                   'nico', "nico:#{ q }%", "#{ q }%")
-    alias_rows =
+            .order('post_count DESC, name ASC')
-        TagName
+            .limit(20))
-        .where('name LIKE ?', "#{ q }%")
+    render json: tags
-        .where.not(canonical_id: nil)
-        .pluck(:canonical_id, :name)
-
-    matched_alias_by_tag_name_id = { }
-    canonical_ids = []
-
-    alias_rows.each do |canonical_id, alias_name|
-      canonical_ids << canonical_id
-      matched_alias_by_tag_name_id[canonical_id] ||= alias_name
-    end
-
-    base = Tag.joins(:tag_name)
-              .includes(:tag_name, :materials, tag_name: :wiki_page)
-    base = base.where('tags.post_count > 0') if present_only
-
-    canonical_hit =
-        base
-        .where(((with_nico ? '(tags.category = ? AND tag_names.name LIKE ?) OR ' : '') +
-                'tag_names.name LIKE ?'),
-               *(with_nico ? ['nico', "nico:#{ q }%"] : []), "#{ q }%")
-
-    tags =
-        if canonical_ids.present?
-          canonical_hit.or(base.where(tag_name_id: canonical_ids.uniq))
-        else
-          canonical_hit
-        end
-
-    tags = tags.order(Arel.sql('post_count DESC, tag_names.name')).limit(20).to_a
-
-    render json: tags.map { |tag|
-      TagRepr.base(tag).merge(matched_alias: matched_alias_by_tag_name_id[tag.tag_name_id])
-    }
   end
 
   def show
-    tag = Tag.joins(:tag_name)
+    tag = Tag.find(params[:id])
-             .includes(:tag_name, :materials, tag_name: :wiki_page)
+    render json: tag
-             .find_by(id: params[:id])
-    if tag
-      render json: TagRepr.base(tag)
-    else
-      head :not_found
-    end
   end
 
   def show_by_name
-    name = params[:name].to_s.strip
+    tag = Tag.find_by(name: params[:name])
-    return head :bad_request if name.blank?
-
-    tag = Tag.joins(:tag_name)
-             .includes(:tag_name, :materials, tag_name: :wiki_page)
-             .find_by(tag_names: { name: })
     if tag
-      render json: TagRepr.base(tag)
+      render json: tag
     else
       head :not_found
     end
   end
 
-  def deerjikists
+  def create
-    tag = Tag.joins(:tag_name)
-             .includes(:tag_name, tag_name: :wiki_page)
-             .find_by(id: params[:id])
-    return head :not_found unless tag
-
-    render json: { tag: TagRepr.base(tag),
-                   deerjikists: DeerjikistRepr.many(tag.deerjikists) }
-  end
-
-  def deerjikists_by_name
-    name = params[:name].to_s.strip
-    return head :bad_request if name.blank?
-
-    tag = Tag.joins(:tag_name)
-             .includes(:tag_name, tag_name: :wiki_page)
-             .find_by(tag_names: { name: })
-    return head :not_found unless tag
-
-    render json: { tag: TagRepr.base(tag),
-                   deerjikists: DeerjikistRepr.many(tag.deerjikists) }
-  end
-
-  def update_deerjikists
-    return head :unauthorized unless current_user
-    return head :forbidden unless current_user.gte_member?
-
-    tag = Tag.joins(:tag_name)
-             .includes(:tag_name, tag_name: :wiki_page)
-             .find_by(id: params[:id])
-    return head :not_found unless tag
-
-    ApplicationRecord.transaction do
-      tag.deerjikists = []
-      params[:_json].each do
-        platform = _1[:platform]
-        code = normalise_deerjikist_code(platform, _1[:code])
-        deerjikist = Deerjikist.find_or_initialize_by(platform:, code:)
-        deerjikist.tag = tag
-        deerjikist.save!
-      end
-    end
-
-    render json: DeerjikistRepr.many(tag.reload.deerjikists)
-  end
-
-  def materials_by_name
-    name = params[:name].to_s.strip
-    return head :bad_request if name.blank?
-
-    tag = Tag.joins(:tag_name)
-             .includes(:tag_name, :materials, tag_name: :wiki_page)
-             .find_by(tag_names: { name: })
-    return head :not_found unless tag
-
-    render json: build_tag_children(tag)
-  end
-
-  def update_all
-    return head :unauthorized unless current_user
-    return head :forbidden unless current_user.gte_member?
-
-    tag = Tag.find_by(id: params[:id])
-    return head :not_found unless tag
-
-    name = params[:name].to_s.strip
-    category = params[:category].to_s.strip
-    return head :unprocessable_entity if name.blank? || category.blank?
-
-    if name != tag.name &&
-        tag.in?([Tag.tagme, Tag.bot, Tag.no_deerjikist, Tag.video, Tag.niconico])
-      return render json: { error: 'システム・タグの名称は変更できません．' },
-                    status: :unprocessable_entity
-    end
-
-    if tag.nico? || category == 'nico'
-      return render json: { error: 'ニコタグは変更できません．' },
-                    status: :unprocessable_entity
-    end
-
-    alias_names = params[:aliases].to_s.split.uniq
-    parent_names = params[:parent_tags].to_s.split.uniq
-
-    ApplicationRecord.transaction do
-      TagVersioning.ensure_snapshot!(tag, created_by_user: current_user)
-
-      old_name = tag.name
-      name_changed = name != old_name
-      wiki_page = tag.tag_name.wiki_page if name_changed
-
-      tag.update!(category:)
-      tag.tag_name.update!(name:)
-
-      alias_names << old_name if name_changed
-      alias_names.delete(name)
-
-      update_aliases!(tag, alias_names)
-      update_parent_tags!(tag, parent_names)
-
-      tag.reload
-
-      record_tag_version!(
-          tag,
-          event_type: :update,
-          created_by_user: current_user,
-          name_changed:,
-          wiki_page:)
-    end
-
-    render json: TagRepr.base(tag.reload)
   end
 
   def update
-    return head :unauthorized unless current_user
-    return head :forbidden unless current_user.gte_member?
-
-    name = params[:name].presence
-    category = params[:category].presence
-
-    tag = Tag.find(params[:id])
-
-    if tag.nico? || (category.present? && category == 'nico')
-      return render json: { error: 'ニコタグは変更できません．' },
-                    status: :unprocessable_entity
-    end
-
-    ApplicationRecord.transaction do
-      TagVersioning.ensure_snapshot!(tag, created_by_user: current_user)
-
-      old_name = tag.name
-      name_changed = name.present? && name != old_name
-      wiki_page = tag.tag_name.wiki_page if name_changed
-
-      tag.tag_name.update!(name:) if name.present?
-      tag.update!(category:) if category.present?
-
-      tag.reload
-
-      record_tag_version!(
-          tag,
-          event_type: :update,
-          created_by_user: current_user,
-          name_changed:,
-          wiki_page:)
-    end
-
-    render json: TagRepr.base(tag.reload)
   end
 
-  private
+  def destroy
-
-  def build_tag_children tag
-    material = tag.materials.first
-    file = nil
-    content_type = nil
-    if material&.file&.attached?
-      file = rails_storage_proxy_url(material.file, only_path: false)
-      content_type = material.file.blob.content_type
-    end
-
-    TagRepr.base(tag).merge(
-        children: tag.children.sort_by { _1.name }.map { build_tag_children(_1) },
-        material: material.as_json&.merge(file:, content_type:))
-  end
-
-  def record_tag_version! tag, event_type:, created_by_user:, name_changed: false, wiki_page: nil
-    if tag.nico?
-      NicoTagVersionRecorder.record!(tag:, event_type:, created_by_user:)
-      return
-    end
-
-    TagVersionRecorder.record!(tag:, event_type:, created_by_user:)
-
-    return unless name_changed
-
-    wiki_page ||= tag.tag_name.wiki_page
-    return unless wiki_page&.wiki_versions&.exists?
-
-    WikiVersionRecorder.record!(
-        page: wiki_page,
-        event_type: :update,
-        created_by_user:)
-  end
-
-  def update_aliases! tag, alias_names
-    alias_names = alias_names.uniq
-
-    affected_tags = [tag]
-
-    current_aliases = tag.tag_name.aliases.to_a
-
-    current_aliases.each do |alias_tag_name|
-      next if alias_names.include?(alias_tag_name.name)
-
-      affected_tags << alias_tag_name.canonical&.tag
-    end
-
-    alias_names.each do |alias_name|
-      alias_tag_name = TagName.find_undiscard_or_create_by!(name: alias_name)
-      affected_tags << alias_tag_name.canonical&.tag
-    end
-
-    affected_tags.compact.uniq.each do |affected_tag|
-      TagVersioning.ensure_snapshot!(affected_tag, created_by_user: current_user)
-    end
-
-    current_aliases.each do |alias_tag_name|
-      next if alias_names.include?(alias_tag_name.name)
-
-      alias_tag_name.update!(canonical: nil)
-    end
-
-    alias_names.each do |alias_name|
-      alias_tag_name = TagName.find_undiscard_or_create_by!(name: alias_name)
-      alias_tag_name.update!(canonical: tag.tag_name)
-    end
-
-    affected_tags.compact.uniq.each do |affected_tag|
-      record_tag_version!(affected_tag, event_type: :update, created_by_user: current_user)
-    end
-  end
-
-  def update_parent_tags! tag, parent_names
-    parent_tags = Tag.normalise_tags!(parent_names, with_tagme: false,
-                                                    with_no_deerjikist: false,
-                                                    deny_nico: true)
-
-    old_parent_tags = tag.parents.to_a
-
-    TagVersioning.record_tag_snapshots!((old_parent_tags + parent_tags).uniq,
-                                        created_by_user: current_user)
-
-    tag.reversed_tag_implications.destroy_all
-
-    parent_tags.each do |parent_tag|
-      next if parent_tag == tag
-
-      TagImplication.create!(tag:, parent_tag:)
-    end
-  end
-
-  def normalise_deerjikist_code platform, code
-    return code if platform != 'youtube' || code[0] != '@'
-
-    url = "https://www.youtube.com/#{ code }"
-
-    html = Net::HTTP.get(URI(url))
-
-    canonical = html[
-        /<link rel="canonical" href="https:\/\/www\.youtube\.com\/channel\/(UC[a-zA-Z0-9_-]{22})"/,
-        1]
-    return canonical if canonical
-
-    html[/"channelId":"(UC[a-zA-Z0-9_-]{22})"/, 1] || html[/\bUC[a-zA-Z0-9_-]{22}\b/]
-  rescue
-    nil
   end
 end

backend/app/controllers/theatre_comments_controller.rb

@@ -1,32 +0,0 @@
-class TheatreCommentsController < ApplicationController
-  def index
-    no_gt = params[:no_gt].to_i
-    no_gt = 0 if no_gt.negative?
-
-    comments = TheatreComment
-               .where(theatre_id: params[:theatre_id])
-               .where('no > ?', no_gt)
-               .order(no: :desc)
-
-    render json: comments.as_json(include: { user: { only: [:id, :name] } })
-  end
-
-  def create
-    return head :unauthorized unless current_user
-
-    content = params[:content]
-    return head :unprocessable_entity if content.blank?
-
-    theatre = Theatre.find_by(id: params[:theatre_id])
-    return head :not_found unless theatre
-
-    comment = nil
-    theatre.with_lock do
-      no = theatre.next_comment_no
-      comment = TheatreComment.create!(theatre:, no:, user: current_user, content:)
-      theatre.update!(next_comment_no: no + 1)
-    end
-
-    render json: comment, status: :created
-  end
-end

backend/app/controllers/theatres_controller.rb

@@ -1,54 +0,0 @@
-class TheatresController < ApplicationController
-  def show
-    theatre = Theatre.find_by(id: params[:id])
-    return head :not_found unless theatre
-
-    render json: TheatreRepr.base(theatre)
-  end
-
-  def watching
-    return head :unauthorized unless current_user
-
-    theatre = Theatre.find_by(id: params[:id])
-    return head :not_found unless theatre
-
-    host_flg = false
-    post_id = nil
-    post_started_at = nil
-
-    theatre.with_lock do
-      TheatreWatchingUser.find_or_initialize_by(theatre:, user: current_user).tap {
-        _1.expires_at = 30.seconds.from_now
-      }.save!
-
-      if (!(theatre.host_user_id?) ||
-          !(theatre.watching_users.exists?(id: theatre.host_user_id)))
-        theatre.update!(host_user_id: current_user.id)
-      end
-
-      host_flg = theatre.host_user_id == current_user.id
-      post_id = theatre.current_post_id
-      post_started_at = theatre.current_post_started_at
-    end
-
-    render json: {
-        host_flg:, post_id:, post_started_at:,
-        watching_users: theatre.watching_users.as_json(only: [:id, :name]) }
-  end
-
-  def next_post
-    return head :unauthorized unless current_user
-
-    theatre = Theatre.find_by(id: params[:id])
-    return head :not_found unless theatre
-    return head :forbidden if theatre.host_user != current_user
-
-    post = Post.where("url LIKE '%nicovideo.jp%'")
-           .or(Post.where("url LIKE '%youtube.com%'"))
-           .order('RAND()')
-           .first
-    theatre.update!(current_post: post, current_post_started_at: Time.current)
-
-    head :no_content
-  end
-end

backend/app/controllers/user_ips_controller.rb

@@ -0,0 +1,16 @@
+class UserIpsController < ApplicationController
+  def index
+  end
+
+  def show
+  end
+
+  def create
+  end
+
+  def update
+  end
+
+  def destroy
+  end
+end

backend/app/controllers/user_post_views_controller.rb

@@ -0,0 +1,16 @@
+class UserPostViewsController < ApplicationController
+  def index
+  end
+
+  def show
+  end
+
+  def create
+  end
+
+  def update
+  end
+
+  def destroy
+  end
+end

backend/app/controllers/users_controller.rb

@@ -1,29 +1,23 @@
 class UsersController < ApplicationController
   def create
-    user = nil
+    user = User.create!(inheritance_code: SecureRandom.uuid, role: 'guest')
-    User.transaction do
-      user = User.create!(inheritance_code: SecureRandom.uuid, role: :guest)
-      attach_ip_address!(user)
-    end
-
     render json: { code: user.inheritance_code,
-                   user: user.slice(:id, :name, :inheritance_code, :role) },
+                   user: user.slice(:id, :name, :inheritance_code, :role) }
-           status: :created
   end
 
   def verify
+    ip_bin = IPAddr.new(request.remote_ip).hton
+    ip_address = IpAddress.find_or_create_by!(ip_address: ip_bin)
+
     user = User.find_by(inheritance_code: params[:code])
     return render json: { valid: false } unless user
-    return head :forbidden if user.banned?
 
-    attach_ip_address!(user)
+    UserIp.find_or_create_by!(user:, ip_address:)
 
     render json: { valid: true, user: user.slice(:id, :name, :inheritance_code, :role) }
   end
 
   def renew
-    return head :unauthorized unless current_user
-
     user = current_user
     user.inheritance_code = SecureRandom.uuid
     user.save!
@@ -45,18 +39,9 @@ class UsersController < ApplicationController
     return head :bad_request if name.blank?
 
     if user.update(name:)
-      render json: user.slice(:id, :name, :inheritance_code, :role), status: :ok
+      render json: user.slice(:id, :name, :inheritance_code, :role), status: :created
     else
       render json: user.errors, status: :unprocessable_entity
     end
   end
-
-  private
-
-  def attach_ip_address! user
-    ip_bin = IPAddr.new(request.remote_ip).hton
-    ip_address = IpAddress.create_or_find_by!(ip_address: ip_bin)
-
-    UserIp.create_or_find_by!(user:, ip_address:)
-  end
 end

backend/app/controllers/wiki_pages_controller.rb

@@ -1,34 +1,20 @@
 class WikiPagesController < ApplicationController
-  rescue_from Wiki::Commit::Conflict, with: :render_wiki_conflict
-
   def index
-    title = params[:title].to_s.strip
+    wiki_pages = WikiPage.all
-    if title.blank?
-      return render json: WikiPageRepr.base(WikiPage.joins(:tag_name).includes(:tag_name))
-    end
 
-    q = WikiPage.joins(:tag_name).includes(:tag_name)
+    render json: wiki_pages
-        .where('tag_names.name LIKE ?', "%#{ WikiPage.sanitize_sql_like(title) }%")
-    render json: WikiPageRepr.base(q.limit(20))
   end
 
   def show
-    page = WikiPage.joins(:tag_name)
+    render_wiki_page_or_404 WikiPage.find(params[:id])
-                   .includes(:tag_name)
-                   .find_by(id: params[:id])
-    render_wiki_page_or_404 page
   end
 
   def show_by_title
-    title = params[:title].to_s.strip
+    render_wiki_page_or_404 WikiPage.find_by(title: params[:title])
-    page = WikiPage.joins(:tag_name)
-                   .includes(:tag_name)
-                   .find_by(tag_name: { name: title })
-    render_wiki_page_or_404 page
   end
 
   def exists
-    if WikiPage.exists?(id: params[:id])
+    if WikiPage.exists?(params[:id])
       head :no_content
     else
       head :not_found
@@ -36,8 +22,7 @@ class WikiPagesController < ApplicationController
   end
 
   def exists_by_title
-    title = params[:title].to_s.strip
+    if WikiPage.exists?(title: params[:title])
-    if WikiPage.joins(:tag_name).exists?(tag_names: { name: title })
       head :no_content
     else
       head :not_found
@@ -46,25 +31,21 @@ class WikiPagesController < ApplicationController
 
   def diff
     id = params[:id]
-    return head :bad_request if id.blank?
+    from = params[:from]
-
-    from = params[:from].presence
     to = params[:to].presence
+    return head :bad_request if id.blank? || from.blank?
 
-    page = WikiPage.joins(:tag_name).includes(:tag_name).find(id)
+    wiki_page_from = WikiPage.find(id)
+    wiki_page_to = WikiPage.find(id)
+    wiki_page_from.sha = from
+    wiki_page_to.sha = to
 
-    from_rev = from && page.wiki_revisions.find(from)
+    diffs = Diff::LCS.sdiff(wiki_page_from.body, wiki_page_to.body)
-    to_rev = to ? page.wiki_revisions.find(to) : page.current_revision
-    if ((from_rev && !(from_rev.content?)) || !(to_rev&.content?))
-      return head :unprocessable_entity
-    end
-
-    diffs = Diff::LCS.sdiff(from_rev&.body&.lines || [], to_rev.body.lines)
     diff_json = diffs.map { |change|
       case change.action
       when ?=
         { type: 'context', content: change.old_element }
-      when ?!
+      when ?|
         [{ type: 'removed', content: change.old_element },
          { type: 'added', content: change.new_element }]
       when ?+
@@ -74,133 +55,97 @@ class WikiPagesController < ApplicationController
       end
     }.flatten.compact
 
-    render json: { wiki_page_id:      page.id,
+    render json: { wiki_page_id:  wiki_page_from.id,
-                   title:             page.title,
+                   title:         wiki_page_from.title,
-                   older_revision_id: from_rev&.id,
+                   older_sha:     wiki_page_from.sha,
-                   newer_revision_id: to_rev.id,
+                   newer_sha:     wiki_page_to.sha,
-                   diff:              diff_json }
+                   diff:          diff_json }
   end
 
   def create
     return head :unauthorized unless current_user
-    return head :forbidden unless current_user.gte_member?
+    return head :forbidden unless ['admin', 'member'].include?(current_user.role)
 
-    title = params[:title].to_s.strip
+    wiki_page = WikiPage.new(title: params[:title], created_user: current_user, updated_user: current_user)
-    body = params[:body].to_s
+    if wiki_page.save
-    message = params[:message].presence
+      wiki_page.set_body params[:body], user: current_user
-
+      render json: wiki_page, status: :created
-    return head :unprocessable_entity if title.blank? || body.blank?
+    else
-
+      render json: { errors: wiki_page.errors.full_messages }, status: :unprocessable_entity
-    tag_name = TagName.find_undiscard_or_create_by!(name: title)
+    end
-
-    page =
-        Wiki::Commit.create_content!(
-            tag_name:,
-            body:,
-            created_by_user: current_user,
-            message:)
-
-    render json: WikiPageRepr.base(page), status: :created
-  rescue ActiveRecord::RecordInvalid, ActiveRecord::RecordNotUnique
-    head :unprocessable_entity
   end
 
   def update
     return head :unauthorized unless current_user
-    return head :forbidden unless current_user.gte_member?
+    return head :forbidden unless current_user.member?
 
-    title = params[:title]&.strip
+    title = params[:title]
-    body = params[:body].to_s
+    body = params[:body]
 
     return head :unprocessable_entity if title.blank? || body.blank?
 
-    page = WikiPage.find(params[:id])
+    wiki_page = WikiPage.find(params[:id])
-    base_revision_id = params[:base_revision_id].presence
+    wiki_page.title = title
-
+    wiki_page.updated_user = current_user
-    ApplicationRecord.transaction do
+    wiki_page.set_body(body, user: current_user)
-      page.lock!
+    wiki_page.save!
-
-      old_title = page.title
-
-      tag = Tag.find_by(tag_name_id: page.tag_name_id)
-
-      if tag && title != old_title
-        TagVersioning.ensure_snapshot!(tag, created_by_user: current_user)
-      end
-
-      page.tag_name.update!(name: title) if title != old_title
-
-      message = params[:message].presence
-      Wiki::Commit.content!(page:,
-                            body:,
-                            created_user: current_user,
-                            message:,
-                            base_revision_id:)
-
-      if tag && title != old_title
-        tag.reload
-        TagVersionRecorder.record!(tag:, event_type: :update, created_by_user: current_user)
-      end
-    end
 
     head :ok
   end
 
   def search
-    index
+    title = params[:title]&.strip
+
+    q = WikiPage.all
+    q = q.where('title LIKE ?', "%#{ WikiPage.sanitize_sql_like(title) }%") if title.present?
+
+    render json: q.limit(20)
   end
 
   def changes
-    id = params[:id].presence
+    id = params[:id]
-    q = WikiRevision.joins(wiki_page: :tag_name)
+    log = if id.present?
-                    .includes(:created_user, wiki_page: :tag_name)
+            wiki.page("#{ id }.md")&.versions
-                    .order(id: :desc)
+          else
-    q = q.where(wiki_page_id: id) if id
+            wiki.repo.log('main', nil)
+          end
+    return render json: [] unless log
 
-    render json: q.limit(200).map { |rev|
+    render json: log.map { |commit|
-      { revision_id:  rev.id,
+      wiki_page = WikiPage.find(commit.message.split(' ')[1].to_i)
-        pred:         rev.base_revision_id,
+      wiki_page.sha = commit.id
-        succ:         nil,
+
-        wiki_page:    { id: rev.wiki_page_id, title: rev.wiki_page.title },
+      next nil if wiki_page.sha.blank?
-        user:         rev.created_user && { id: rev.created_user.id, name: rev.created_user.name },
+
-        kind:         rev.kind,
+      user = User.find(commit.author.name.to_i)
-        message:      rev.message,
+
-        timestamp:    rev.created_at }
+      { sha:          wiki_page.sha,
+        pred:         wiki_page.pred,
+        succ:         wiki_page.succ,
+        wiki_page:    wiki_page && { id: wiki_page.id, title: wiki_page.title },
+        user:         user && { id: user.id, name: user.name },
+        change_type:  commit.message.split(' ')[0].downcase[0...(-1)],
+        timestamp:    commit.authored_date }
     }.compact
   end
 
   private
 
-  def render_wiki_page_or_404 page
+  WIKI_PATH = Rails.root.join('wiki').to_s
-    return head :not_found unless page
 
-    rev = find_revision(page)
+  def wiki
-    return head :not_found unless rev
+    @wiki ||= Gollum::Wiki.new(WIKI_PATH)
-
-    if rev.redirect?
-      return (
-          redirect_to wiki_page_by_title_path(title: rev.redirect_page.title),
-                      status: :moved_permanently)
-    end
-
-    body = rev.body
-    revision_id = rev.id
-    pred = page.pred_revision_id(revision_id)
-    succ = page.succ_revision_id(revision_id)
-    updated_at = rev.created_at
-
-    render json: WikiPageRepr.base(page).merge(body:, revision_id:, pred:, succ:, updated_at:)
   end
 
-  def find_revision page
+  def render_wiki_page_or_404 wiki_page
-    if params[:version].present?
+    return head :not_found unless wiki_page
-      page.wiki_revisions.find_by(id: params[:version])
-    else
-      page.current_revision
-    end
-  end
 
-  def render_wiki_conflict err
+    wiki_page.sha = params[:version].presence
-    render json: { error: 'conflict', message: err.message }, status: :conflict
+
+    body = wiki_page.body
+    sha = wiki_page.sha
+    pred = wiki_page.pred
+    succ = wiki_page.succ
+    render json: wiki_page.as_json.merge(body:, sha:, pred:, succ:)
   end
 end

backend/app/models/deerjikist.rb

@@ -1,21 +0,0 @@
-class Deerjikist < ApplicationRecord
-  self.primary_key = :platform, :code
-
-  belongs_to :tag
-
-  validates :platform, presence: true
-  validates :code, presence: true
-  validates :tag_id, presence: true
-
-  validate :tag_must_be_deerjikist
-
-  enum :platform, nico: 'nico', youtube: 'youtube'
-
-  private
-
-  def tag_must_be_deerjikist
-    if tag && !(tag.deerjikist?)
-      errors.add :tag, 'タグはニジラー・カテゴリである必要があります．'
-    end
-  end
-end

backend/app/models/ip_address.rb

@@ -1,10 +1,6 @@
 class IpAddress < ApplicationRecord
   validates :ip_address, presence: true, length: { maximum: 16 }
+  validates :banned, inclusion: { in: [true, false] }
 
-  has_many :user_ips, dependent: :destroy
+  has_many :users
-  has_many :users, through: :user_ips
-
-  def banned? = banned_at.present?
-  def ban! = banned? || update!(banned_at: Time.current)
-  def unban! = update!(banned_at: nil)
 end

backend/app/models/material.rb

@@ -1,39 +0,0 @@
-class Material < ApplicationRecord
-  include MyDiscard
-
-  default_scope -> { kept }
-
-  belongs_to :parent, class_name: 'Material', optional: true
-  has_many :children, class_name: 'Material', foreign_key: :parent_id, dependent: :nullify
-
-  belongs_to :tag, optional: true
-  belongs_to :created_by_user, class_name: 'User', optional: true
-  belongs_to :updated_by_user, class_name: 'User', optional: true
-
-  has_one_attached :file, dependent: :purge
-
-  validates :tag_id, presence: true, uniqueness: true
-
-  validate :file_must_be_attached
-  validate :tag_must_be_material_category
-
-  def content_type
-    return nil unless file&.attached?
-
-    file.blob.content_type
-  end
-
-  private
-
-  def file_must_be_attached
-    return if url.present? || file.attached?
-
-    errors.add(:url, 'URL かファイルのどちらかは必須です．')
-  end
-
-  def tag_must_be_material_category
-    return if tag.blank? || tag.character? || tag.material?
-
-    errors.add(:tag, '素材カテゴリのタグを指定してください．')
-  end
-end

backend/app/models/my_discard.rb

@@ -1,24 +0,0 @@
-module MyDiscard
-  extend ActiveSupport::Concern
-
-  included do
-    include Discard::Model
-
-    default_scope -> { kept }
-  end
-
-  class_methods do
-    def find_undiscard_or_create_by! attrs, &block
-      record = with_discarded.find_by(attrs)
-
-      if record&.discarded?
-        record.undiscard!
-        record.update_columns(created_at: record.reload.updated_at)
-      end
-
-      record or create!(attrs, &block)
-    rescue ActiveRecord::RecordNotUnique
-      retry
-    end
-  end
-end

backend/app/models/nico_tag_version.rb

@@ -1,7 +0,0 @@
-class NicoTagVersion < ApplicationRecord
-  include VersionRecord
-
-  belongs_to :tag
-
-  validates :name, presence: true
-end

backend/app/models/post.rb

@@ -1,74 +1,46 @@
 class Post < ApplicationRecord
   require 'mini_magick'
 
+  belongs_to :parent, class_name: 'Post', optional: true, foreign_key: 'parent_id'
   belongs_to :uploaded_user, class_name: 'User', optional: true
 
   has_many :post_tags, dependent: :destroy, inverse_of: :post
   has_many :active_post_tags, -> { kept }, class_name: 'PostTag', inverse_of: :post
   has_many :post_tags_with_discarded, -> { with_discarded }, class_name: 'PostTag'
   has_many :tags, through: :active_post_tags
-
+  has_many :user_post_views, dependent: :destroy
-  has_many :user_post_views, dependent: :delete_all
+  has_many :post_similarities_as_post,
-  has_many :post_similarities, dependent: :delete_all
+           class_name: 'PostSimilarity',
-  has_many :post_versions
+           foreign_key: :post_id
-
+  has_many :post_similarities_as_target_post,
-  has_many :parent_post_implications,
+           class_name: 'PostSimilarity',
-           class_name: 'PostImplication',
+           foreign_key: :target_post_id
-           foreign_key: :post_id,
-           dependent: :destroy,
-           inverse_of: :post
-  has_many :parents, through: :parent_post_implications, source: :parent_post
-
-  has_many :child_post_implications,
-           class_name: 'PostImplication',
-           foreign_key: :parent_post_id,
-           dependent: :destroy,
-           inverse_of: :parent_post
-  has_many :children, through: :child_post_implications, source: :post
-
   has_one_attached :thumbnail
 
-  attribute :version_no, :integer, default: 1
-
-  before_validation :normalise_url
-
-  validates :url, presence: true, uniqueness: true
-
   validate :validate_original_created_range
-  validate :url_must_be_http_url
-
-  def parent_posts = parents
-
-  def child_posts = children
-
-  def sibling_posts
-    parent_post_ids = parent_posts.order(:id).pluck(:id)
-
-    parent_post_ids.to_h { [_1, PostImplication.where(parent_post: _1).map(&:post)] }
-  end
 
   def as_json options = { }
-    super(options).merge(thumbnail: thumbnail.attached? ?
+    super(options).merge({ thumbnail: thumbnail.attached? ?
-                                    Rails.application.routes.url_helpers.rails_blob_url(
+                                      Rails.application.routes.url_helpers.rails_blob_url(
-                                        thumbnail, only_path: false) :
+                                          thumbnail, only_path: false) :
-                                    nil)
+                                      nil })
   rescue
     super(options).merge(thumbnail: nil)
   end
 
-  def snapshot_tag_names = tags.joins(:tag_name).order('tag_names.name').pluck('tag_names.name')
+  def related(limit: nil)
+    ids_with_cos =
+        post_similarities_as_post.select(:target_post_id, :cos)
+                                 .map { |ps| [ps.target_post_id, ps.cos] } +
+        post_similarities_as_target_post.select(:post_id, :cos)
+                                        .map { |ps| [ps.post_id, ps.cos] }
 
-  def snapshot_parent_post_ids = parents.order(:id).pluck(:id)
+    sorted = ids_with_cos.sort_by { |_, cos| -cos }
 
-  def related limit: nil
+    ids = sorted.map(&:first)
-    ids = post_similarities.order(cos: :desc)
+    ids = ids.first(limit) if limit
-    ids = ids.limit(limit) if limit
-    ids = ids.pluck(:target_post_id)
-    return Post.none if ids.empty?
 
-    Post.where(id: ids)
+    Post.where(id: ids).index_by(&:id).values_at(*ids)
-        .with_attached_thumbnail
-        .order(Arel.sql("FIELD(posts.id, #{ ids.join(',') })"))
   end
 
   def resized_thumbnail!
@@ -97,33 +69,4 @@ class Post < ApplicationRecord
       errors.add :original_created_before, 'オリジナルの作成日時の順番がをかしぃです．'
     end
   end
-
-  def url_must_be_http_url
-    begin
-      u = URI.parse(url)
-    rescue URI::InvalidURIError
-      errors.add(:url, 'URL が不正です．')
-      return
-    end
-
-    if !(u in URI::HTTP) || u.host.blank?
-      errors.add(:url, 'URL が不正です．')
-      return
-    end
-  end
-
-  def normalise_url
-    return if url.blank?
-
-    self.url = url.strip
-
-    u = URI.parse(url)
-    return unless u in URI::HTTP
-
-    u.host = u.host.downcase if u.host
-    u.path = u.path.sub(/\/\Z/, '') if u.path.present?
-    self.url = u.to_s
-  rescue URI::InvalidURIError
-    ;
-  end
 end

backend/app/models/post_implication.rb

@@ -1,19 +0,0 @@
-class PostImplication < ApplicationRecord
-  self.primary_key = :post_id, :parent_post_id
-
-  belongs_to :post, inverse_of: :parent_post_implications
-  belongs_to :parent_post, class_name: 'Post', inverse_of: :child_post_implications
-
-  validates :post_id, presence: true, uniqueness: { scope: :parent_post_id }
-  validates :parent_post_id, presence: true
-
-  validate :parent_post_mustnt_be_itself
-
-  private
-
-  def parent_post_mustnt_be_itself
-    if parent_post_id == post_id
-      errors.add :parent_post_id, '親投稿に同じ投稿を設定することはできません．'
-    end
-  end
-end

backend/app/models/post_similarity.rb

@@ -1,6 +1,4 @@
 class PostSimilarity < ApplicationRecord
-  self.primary_key = :post_id, :target_post_id
+  belongs_to :post, class_name: 'Post', foreign_key: 'post_id'
-
+  belongs_to :target_post, class_name: 'Post', foreign_key: 'target_post_id'
-  belongs_to :post
-  belongs_to :target_post, class_name: 'Post'
 end

backend/app/models/post_tag.rb

@@ -1,10 +1,6 @@
 class PostTag < ApplicationRecord
   include Discard::Model
 
-  before_destroy do
-    raise ActiveRecord::ReadOnlyRecord, '消さないでください．'
-  end
-
   belongs_to :post
   belongs_to :tag, counter_cache: :post_count
   belongs_to :created_user, class_name: 'User', optional: true

backend/app/models/post_version.rb

@@ -1,22 +0,0 @@
-class PostVersion < ApplicationRecord
-  include VersionRecord
-
-  belongs_to :post
-  belongs_to :parent, class_name: 'Post', optional: true
-
-  validates :url, presence: true
-
-  validate :validate_original_created_range
-
-  private
-
-  def validate_original_created_range
-    f = original_created_from
-    b = original_created_before
-    return if f.blank? || b.blank?
-
-    if f >= b
-      errors.add :original_created_before, 'オリジナルの作成日時の順番がをかしぃです．'
-    end
-  end
-end

backend/app/models/tag.rb

@@ -1,113 +1,81 @@
-require 'set'
-
-
 class Tag < ApplicationRecord
-  include MyDiscard
+  has_many :post_tags, dependent: :delete_all, inverse_of: :tag
-
-  class NicoTagNormalisationError < ArgumentError
-    ;
-  end
-
-  has_many :post_tags, inverse_of: :tag
   has_many :active_post_tags, -> { kept }, class_name: 'PostTag', inverse_of: :tag
   has_many :post_tags_with_discarded, -> { with_discarded }, class_name: 'PostTag'
   has_many :posts, through: :active_post_tags
+  has_many :tag_aliases, dependent: :destroy
 
   has_many :nico_tag_relations, foreign_key: :nico_tag_id, dependent: :destroy
   has_many :linked_tags, through: :nico_tag_relations, source: :tag
 
-  has_many :reversed_nico_tag_relations,
+  has_many :reversed_nico_tag_relations, class_name: 'NicoTagRelation',
-           class_name: 'NicoTagRelation', foreign_key: :tag_id, dependent: :destroy
+                                         foreign_key: :tag_id,
+                                         dependent: :destroy
   has_many :linked_nico_tags, through: :reversed_nico_tag_relations, source: :nico_tag
 
   has_many :tag_implications, foreign_key: :parent_tag_id, dependent: :destroy
   has_many :children, through: :tag_implications, source: :tag
 
-  has_many :reversed_tag_implications,
+  has_many :reversed_tag_implications, class_name: 'TagImplication',
-           class_name: 'TagImplication', foreign_key: :tag_id, dependent: :destroy
+                                       foreign_key: :tag_id,
+                                       dependent: :destroy
   has_many :parents, through: :reversed_tag_implications, source: :parent_tag
 
-  has_many :tag_similarities, dependent: :delete_all
+  enum :category, { deerjikist:  'deerjikist',
-  has_many :tag_similarities_as_target,
+                    meme:        'meme',
-           class_name: 'TagSimilarity', foreign_key: :target_tag_id, dependent: :delete_all
+                    character:   'character',
-
+                    general:     'general',
-  has_many :deerjikists, dependent: :delete_all
+                    material:    'material',
-  has_many :materials
+                    nico:        'nico',
-
+                    meta:        'meta' }
-  has_many :tag_versions
-  has_many :nico_tag_versions
-
-  belongs_to :tag_name
-  delegate :wiki_page, to: :tag_name
-
-  attribute :version_no, :integer, default: 1
-
-  delegate :name, to: :tag_name, allow_nil: true
-  validates :tag_name, presence: true
-
-  enum :category, deerjikist:  'deerjikist',
-                  meme:        'meme',
-                  character:   'character',
-                  general:     'general',
-                  material:    'material',
-                  nico:        'nico',
-                  meta:        'meta'
 
+  validates :name, presence: true, length: { maximum: 255 }
   validates :category, presence: true, inclusion: { in: Tag.categories.keys }
 
   validate :nico_tag_name_must_start_with_nico
-  validate :tag_name_must_be_canonical
-  validate :category_must_be_deerjikist_with_deerjikists
 
-  scope :nico_tags, -> { nico }
+  scope :nico_tags, -> { where(category: :nico) }
 
   CATEGORY_PREFIXES = {
-      'general:'    => :general,
+      'gen:'  => 'general',
-      'gen:'        => :general,
+      'djk:'  => 'deerjikist',
-      'deerjikist:' => :deerjikist,
+      'meme:' => 'meme',
-      'djk:'        => :deerjikist,
+      'chr:'  => 'character',
-      'meme:'       => :meme,
+      'mtr:'  => 'material',
-      'character:'  => :character,
+      'meta:' => 'meta' }.freeze
-      'chr:'        => :character,
-      'material:'   => :material,
-      'mtr:'        => :material,
-      'meta:'       => :meta }.freeze
 
-  def name= val
+  def self.tagme
-    (self.tag_name ||= build_tag_name).name = val
+    @tagme ||= Tag.find_or_create_by!(name: 'タグ希望') do |tag|
+      tag.category = 'meta'
+    end
   end
 
-  def has_wiki = wiki_page.present?
+  def self.bot
-
+    @bot ||= Tag.find_or_create_by!(name: 'bot操作') do |tag|
-  def material_id = materials.first&.id
+      tag.category = 'meta'
-
-  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)
-  def self.no_deerjikist = find_or_create_by_tag_name!('ニジラー情報不詳', category: :meta)
-  def self.video = find_or_create_by_tag_name!('動画', category: :meta)
-  def self.niconico = find_or_create_by_tag_name!('ニコニコ', category: :meta)
-  def self.youtube = find_or_create_by_tag_name!('YouTube', category: :meta)
-
-  def self.normalise_tags! tag_names, with_tagme: true,
-                                      with_no_deerjikist: true,
-                                      deny_nico: true
-    if deny_nico && tag_names.any? { |n| n.downcase.start_with?('nico:') }
-      raise NicoTagNormalisationError
     end
+  end
 
+  def self.no_deerjikist
+    @no_deerjikist ||= Tag.find_or_initialize_by(name: 'ニジラー情報不詳') do |tag|
+      tag.category = 'meta'
+    end
+  end
+
+  def self.normalise_tags tag_names, with_tagme: true
     tags = tag_names.map do |name|
-      pf, cat = CATEGORY_PREFIXES.find { |p, _| name.downcase.start_with?(p) } || ['', nil]
+      pf, cat = CATEGORY_PREFIXES.find { |p, _| name.start_with?(p) } || ['', nil]
-      name = TagName.canonicalise(name.sub(/\A#{ pf }/i, '')).first
+      name.delete_prefix!(pf)
-      find_or_create_by_tag_name!(name, category: (cat || :general)).tap do |tag|
+      Tag.find_or_initialize_by(name:).tap do |tag|
-        tag.update!(category: cat) if cat && tag.category != cat
+        if cat && tag.category != cat
+          tag.category = cat
+          tag.save!
+        end
       end
     end
-
     tags << Tag.tagme if with_tagme && tags.size < 10 && tags.none?(Tag.tagme)
-    tags << Tag.no_deerjikist if with_no_deerjikist && tags.all? { |t| !(t.deerjikist?) }
+    tags << Tag.no_deerjikist if tags.all? { |t| t.category != 'deerjikist' }
-    tags.uniq(&:id)
+    tags.uniq
   end
 
   def self.expand_parent_tags tags
@@ -133,99 +101,12 @@ class Tag < ApplicationRecord
     (result + tags).uniq { |t| t.id }
   end
 
-  def self.find_or_create_by_tag_name! name, category:
-    tn = TagName.find_undiscard_or_create_by!(name: name.to_s.strip)
-    tn = tn.canonical if tn.canonical_id?
-
-    Tag.find_undiscard_or_create_by!(tag_name_id: tn.id) do |t|
-      t.category = category
-    end
-  rescue ActiveRecord::RecordNotUnique
-    retry
-  end
-
-  def self.merge_tags! target_tag, source_tags, created_by_user: nil
-    target_tag => Tag
-
-    affected_post_ids = Set.new
-
-    Tag.transaction do
-      TagVersioning.ensure_snapshot!(target_tag, created_by_user:)
-
-      Array(source_tags).compact.uniq.each do |source_tag|
-        source_tag => Tag
-
-        next if source_tag == target_tag
-
-        TagVersioning.ensure_snapshot!(source_tag, created_by_user:)
-
-        source_tag.post_tags.kept.find_each do |source_pt|
-          post_id = source_pt.post_id
-          affected_post_ids << post_id
-          source_pt.discard_by!(created_by_user)
-          unless PostTag.kept.exists?(post_id:, tag: target_tag)
-            PostTag.create!(post_id:, tag: target_tag)
-          end
-        end
-
-        source_tag_name = source_tag.tag_name
-
-        if source_tag_name.wiki_page.present?
-          raise ActiveRecord::RecordInvalid.new(source_tag_name)
-        end
-
-        TagVersioning.record!(source_tag, event_type: :discard, created_by_user:)
-        source_tag.discard!
-
-        if source_tag.nico?
-          source_tag_name.discard!
-        else
-          source_tag_name.update_columns(canonical_id: target_tag.tag_name_id,
-                                         updated_at: Time.current)
-        end
-
-        TagVersioning.record!(target_tag, event_type: :update, created_by_user:)
-      end
-
-      Post.where(id: affected_post_ids.to_a).find_each do |post|
-        PostVersionRecorder.ensure_snapshot!(post, created_by_user:)
-        PostVersionRecorder.record!(post:, event_type: :update, created_by_user:)
-      end
-
-      # 投稿件数を再集計
-      target_tag.update_columns(post_count: PostTag.kept.where(tag: target_tag).count)
-    end
-
-    target_tag.reload
-  end
-
-  def snapshot_aliases = tag_name.aliases.kept.order(:name).pluck(:name)
-
-  def snapshot_parent_tag_ids = parents.order(:id).pluck(:id)
-
-  def snapshot_linked_tag_names
-    linked_tags.joins(:tag_name).order('tag_names.name').pluck('tag_names.name')
-  end
-
   private
 
   def nico_tag_name_must_start_with_nico
-    n = name.to_s
+    if ((category == 'nico' && !(name.start_with?('nico:'))) || 
-    if ((nico? && !(n.downcase.start_with?('nico:'))) || 
+        (category != 'nico' && name.start_with?('nico:')))
-        (!(nico?) && n.downcase.start_with?('nico:')))
       errors.add :name, 'ニコニコ・タグの命名規則に反してゐます．'
     end
   end
-
-  def tag_name_must_be_canonical
-    if tag_name&.canonical_id?
-      errors.add :tag_name, 'tag_names へは実体を示す必要があります．'
-    end
-  end
-
-  def category_must_be_deerjikist_with_deerjikists
-    if !(deerjikist?) && deerjikists.exists?
-      errors.add :category, 'ニジラーと紐づいてゐるタグはニジラー・カテゴリである必要があります．'
-    end
-  end
 end

backend/app/models/tag_alias.rb

@@ -0,0 +1,6 @@
+class TagAlias < ApplicationRecord
+  belongs_to :tag
+
+  validates :tag_id, presence: true
+  validates :name, presence: true, length: { maximum: 255 }, uniqueness: true
+end

backend/app/models/tag_name.rb

@@ -1,51 +0,0 @@
-class TagName < ApplicationRecord
-  include MyDiscard
-
-  has_one :tag
-  has_one :wiki_page
-
-  belongs_to :canonical, class_name: 'TagName', optional: true
-  has_many :aliases, class_name: 'TagName', foreign_key: :canonical_id
-
-  validates :name, presence: true, length: { maximum: 255 }, uniqueness: true
-
-  validate :canonical_must_be_canonical
-  validate :alias_name_must_not_have_prefix
-  validate :canonical_must_not_be_present_with_tag_or_wiki_page
-  validate :name_must_be_sanitised
-
-  def self.canonicalise names
-    names = Array(names).map { |n| n.to_s.strip }.reject(&:blank?)
-    return [] if names.blank?
-
-    tns = TagName.includes(:canonical).where(name: names).index_by(&:name)
-
-    names.map { |name| tns[name]&.canonical&.name || name }.uniq
-  end
-
-  private
-
-  def canonical_must_be_canonical
-    if canonical&.canonical_id?
-      errors.add :canonical, 'canonical は実体を示す必要があります．'
-    end
-  end
-
-  def alias_name_must_not_have_prefix
-    if canonical_id? && name.to_s.include?(':')
-      errors.add :name, 'エーリアス名にプレフィクスを含むことはできません．'
-    end
-  end
-
-  def canonical_must_not_be_present_with_tag_or_wiki_page
-    if canonical_id? && (tag || wiki_page)
-      errors.add :canonical, 'タグもしくは Wiki の参照がある名前はエーリアスになれません．'
-    end
-  end
-
-  def name_must_be_sanitised
-    if name? && name != TagNameSanitisationRule.sanitise(name)
-      errors.add :name, '名前に使用できない文字が含まれてゐます．'
-    end
-  end
-end

backend/app/models/tag_name_sanitisation_rule.rb

@@ -1,58 +0,0 @@
-class TagNameSanitisationRule < ApplicationRecord
-  include Discard::Model
-
-  self.primary_key = :priority
-
-  default_scope -> { kept }
-
-  validates :source_pattern, presence: true, uniqueness: true
-
-  validate :source_pattern_must_be_regexp
-
-  class << self
-    def sanitise(name) =
-        rules.reduce(name.dup) { |name, (pattern, replacement)| name.gsub(pattern, replacement) }
-
-    def apply!
-      TagName.find_each do |tn|
-        name = sanitise(tn.name)
-        next if name == tn.name
-
-        TagName.transaction do
-          existing_tn = TagName.find_by(name:)
-          if existing_tn
-            existing_tn = existing_tn.canonical || existing_tn
-            next if existing_tn.id == tn.id
-
-            existing_tag = Tag.find_by(tag_name_id: existing_tn.id)
-            source_tag = Tag.find_by(tag_name_id: tn.id)
-
-            if existing_tag
-              Tag.merge_tags!(existing_tag, source_tag) if tn.tag
-            elsif source_tag
-              source_tag.update_columns(tag_name_id: existing_tn.id, updated_at: Time.current)
-            end
-            tn.discard!
-
-            next
-          end
-
-          # TagName 側の自動サニタイズを回避
-          tn.update_columns(name:, updated_at: Time.current)
-        end
-      end
-    end
-
-    private
-
-    def rules = kept.order(:priority).map { |r| [Regexp.new(r.source_pattern), r.replacement] }
-  end
-
-  private
-
-  def source_pattern_must_be_regexp
-    Regexp.new(source_pattern)
-  rescue RegexpError
-    errors.add :source_pattern, '変な正規表現だね〜（笑）'
-  end
-end

backend/app/models/tag_similarity.rb

@@ -1,6 +0,0 @@
-class TagSimilarity < ApplicationRecord
-  self.primary_key = :tag_id, :target_tag_id
-
-  belongs_to :tag
-  belongs_to :target_tag, class_name: 'Tag'
-end

backend/app/models/tag_version.rb

@@ -1,15 +0,0 @@
-class TagVersion < ApplicationRecord
-  include VersionRecord
-
-  belongs_to :tag
-
-  enum :category, { deerjikist: 'deerjikist',
-                    meme: 'meme',
-                    character: 'character',
-                    general: 'general',
-                    material: 'material',
-                    meta: 'meta' }, validate: true
-
-  validates :name, presence: true
-  validates :category, presence: true
-end

backend/app/models/theatre.rb

@@ -1,13 +0,0 @@
-class Theatre < ApplicationRecord
-  include MyDiscard
-
-  has_many :comments, class_name: 'TheatreComment'
-  has_many :theatre_watching_users, dependent: :delete_all
-  has_many :active_theatre_watching_users, -> { active },
-           class_name: 'TheatreWatchingUser', inverse_of: :theatre
-  has_many :watching_users, through: :active_theatre_watching_users, source: :user
-
-  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'
-end

backend/app/models/theatre_comment.rb

@@ -1,8 +0,0 @@
-class TheatreComment < ApplicationRecord
-  include Discard::Model
-
-  self.primary_key = :theatre_id, :no
-
-  belongs_to :theatre
-  belongs_to :user
-end

backend/app/models/theatre_watching_user.rb

@@ -1,13 +0,0 @@
-class TheatreWatchingUser < ApplicationRecord
-  self.primary_key = :theatre_id, :user_id
-
-  belongs_to :theatre
-  belongs_to :user
-
-  scope :active, -> { where('expires_at >= ?', Time.current) }
-  scope :expired, -> { where('expires_at < ?', Time.current) }
-
-  def active? = expires_at >= Time.current
-
-  def refresh! = update!(expires_at: 30.seconds.from_now)
-end

backend/app/models/user.rb

@@ -1,27 +1,29 @@
 class User < ApplicationRecord
-  enum :role, guest: 'guest', member: 'member', admin: 'admin'
+  enum :role, { guest: 'guest', member: 'member', admin: 'admin' }
 
   validates :name, length: { maximum: 255 }
   validates :inheritance_code, presence: true, length: { maximum: 64 }
   validates :role, presence: true, inclusion: { in: roles.keys }
+  validates :banned, inclusion: { in: [true, false] }
 
-  has_many :created_posts,
+  has_many :posts
-           class_name: 'Post', foreign_key: :uploaded_user_id, dependent: :nullify
   has_many :settings
   has_many :user_ips, dependent: :destroy
   has_many :ip_addresses, through: :user_ips
   has_many :user_post_views, dependent: :destroy
   has_many :viewed_posts, through: :user_post_views, source: :post
-  has_many :created_wiki_pages,
+  has_many :created_wiki_pages, class_name: 'WikiPage', foreign_key: 'created_user_id', dependent: :nullify
-           class_name: 'WikiPage', foreign_key: :created_user_id, dependent: :nullify
+  has_many :updated_wiki_pages, class_name: 'WikiPage', foreign_key: 'updated_user_id', dependent: :nullify
-  has_many :updated_wiki_pages,
-           class_name: 'WikiPage', foreign_key: :updated_user_id, dependent: :nullify
 
-  def viewed?(post) = user_post_views.exists?(post_id: post.id)
+  def viewed? post
+    user_post_views.exists? post_id: post.id
+  end
 
-  def gte_member? = member? || admin?
+  def member?
+    ['member', 'admin'].include?(role)
+  end
 
-  def banned? = banned_at.present?
+  def admin?
-  def ban! = banned? || update!(banned_at: Time.current)
+    role == 'admin'
-  def unban! = update!(banned_at: nil)
+  end
 end

backend/app/models/user_ip.rb

@@ -1,6 +1,4 @@
 class UserIp < ApplicationRecord
-  self.primary_key = :user_id, :ip_address_id
-
   belongs_to :user
   belongs_to :ip_address
 

backend/app/models/user_post_view.rb

@@ -1,6 +1,4 @@
 class UserPostView < ApplicationRecord
-  self.primary_key = :user_id, :post_id
-
   belongs_to :user
   belongs_to :post
 

backend/app/models/version_record.rb

@@ -1,19 +0,0 @@
-module VersionRecord
-  extend ActiveSupport::Concern
-
-  def readonly? = persisted?
-
-  included do
-    belongs_to :created_by_user, class_name: 'User', optional: true
-
-    enum :event_type, { create: 'create',
-                        update: 'update',
-                        discard: 'discard',
-                        restore: 'restore' }, prefix: true, validate: true
-
-    validates :version_no, presence: true, numericality: { only_integer: true, greater_than: 0 }
-    validates :event_type, presence: true
-
-    scope :chronological, -> { order(:version_no, :id) }
-  end
-end

backend/app/models/wiki_line.rb

@@ -1,15 +0,0 @@
-class WikiLine < ApplicationRecord
-  has_many :wiki_revision_lines, dependent: :restrict_with_exception
-
-  validates :sha256, presence: true, uniqueness: true, length: { is: 64 }
-  validates :body, presence: true
-
-  def self.upsert_by_body! body
-    sha = Digest::SHA256.hexdigest(body)
-    now = Time.current
-
-    upsert(sha256: sha, body:, created_at: now, updated_at: now)
-
-    find_by!(sha256: sha)
-  end
-end

backend/app/models/wiki_page.rb

@@ -1,54 +1,80 @@
-require 'set'
+require 'gollum-lib'
 
 
 class WikiPage < ApplicationRecord
-  include MyDiscard
+  belongs_to :tag, optional: true
+  belongs_to :created_user, class_name: 'User', foreign_key: 'created_user_id'
+  belongs_to :updated_user, class_name: 'User', foreign_key: 'updated_user_id'
 
-  has_many :wiki_revisions, dependent: :destroy
+  validates :title, presence: true, length: { maximum: 255 }, uniqueness: true
-  belongs_to :created_user, class_name: 'User'
-  belongs_to :updated_user, class_name: 'User'
 
-  has_many :redirected_from_revisions,
+  def as_json options = { }
-           class_name: 'WikiRevision',
+    self.sha = nil
-           foreign_key: :redirect_page_id,
+    super options
-           dependent: :nullify
-
-  has_many :wiki_versions
-
-  attribute :version_no, :integer, default: 1
-
-  belongs_to :tag_name
-  validates :tag_name, presence: true
-  validates :body, presence: true
-
-  def title = tag_name.name
-
-  def title= val
-    (self.tag_name ||= build_tag_name).name = val
   end
 
-  def current_revision = wiki_revisions.order(id: :desc).first
+  def sha= val
-
+    if val.present?
-  def resolve_redirect limit: 10
+      @sha = val
-    page = self
+      @page = wiki.page("#{ id }.md", @sha)
-    visited = Set.new
+    else
-
+      @page = wiki.page("#{ id }.md")
-    limit.times do
+      @sha = @page.versions.first.id
-      return page if visited.include?(page.id)
-
-      visited.add(page.id)
-
-      rev = page.current_revision
-      return page if !(rev&.redirect?) || !(rev.redirect_page)
-
-      page = rev.redirect_page
     end
-
+    vers = @page.versions
-    page
+    idx = vers.find_index { |ver| ver.id == @sha }
+    if idx
+      @pred = vers[idx + 1]&.id
+      @succ = idx.positive? ? vers[idx - 1].id : nil
+      @updated_at = vers[idx].authored_date
+    else
+      @sha = nil
+      @pred = nil
+      @succ = nil
+      @updated_at = nil
+    end
+    @sha
   end
 
-  def pred_revision_id(revision_id) =
+  def sha
-      wiki_revisions.where('id < ?', revision_id).order(id: :desc).limit(1).pick(:id)
+    @sha
-  def succ_revision_id(revision_id) =
+  end
-      wiki_revisions.where('id > ?', revision_id).order(id: :asc).limit(1).pick(:id)
+
+  def pred
+    @pred
+  end
+
+  def succ
+    @succ
+  end
+
+  def updated_at
+    @updated_at
+  end
+
+  def body
+    sha = nil unless @page
+    @page&.raw_data&.force_encoding('UTF-8')
+  end
+
+  def set_body content, user:
+    commit_info = { name:   user.id.to_s,
+                    email:  'dummy@example.com' }
+    page = wiki.page("#{ id }.md")
+    if page
+      commit_info[:message] = "Updated #{ id }"
+      wiki.update_page(page, id.to_s, :markdown, content, commit_info)
+    else
+      commit_info[:message] = "Created #{ id }"
+      wiki.write_page(id.to_s, :markdown, content, commit_info)
+    end
+  end
+
+  private
+
+  WIKI_PATH = Rails.root.join('wiki').to_s
+
+  def wiki
+    @wiki ||= Gollum::Wiki.new(WIKI_PATH)
+  end
 end

backend/app/models/wiki_revision.rb

@@ -1,55 +0,0 @@
-class WikiRevision < ApplicationRecord
-  belongs_to :wiki_page
-  belongs_to :base_revision, class_name: 'WikiRevision', optional: true
-  belongs_to :created_user, class_name: 'User'
-  belongs_to :redirect_page, class_name: 'WikiPage', optional: true
-
-  has_many :wiki_revision_lines, dependent: :delete_all
-  has_many :wiki_lines, through: :wiki_revision_lines
-
-  enum :kind, content: 0, redirect: 1
-
-  validates :kind, presence: true
-  validates :lines_count, numericality: { only_integer: true, greater_than_or_equal_to: 0 }
-  validates :tree_sha256, length: { is: 64 }, allow_nil: true
-
-  validate :kind_consistency
-
-  def body
-    return unless content?
-
-    wiki_revision_lines
-        .includes(:wiki_line)
-        .order(:position)
-        .map { |rev| rev.wiki_line.body }
-        .join("\n")
-  end
-
-  private
-
-  def kind_consistency
-    if content?
-      if tree_sha256.blank?
-        errors.add(:tree_sha256, '種類がページの場合は必須です．') 
-      end
-
-      if redirect_page_id.present?
-        errors.add(:redirect_page_id, '種類がページの場合は空である必要があります．')
-      end
-    end
-
-    if redirect?
-      if redirect_page_id.blank?
-        errors.add(:redirect_page_id, '種類がリダイレクトの場合は必須です．')
-      end
-
-      if tree_sha256.present?
-        errors.add(:tree_sha256, '種類がリダイレクトの場合は空である必要があります．')
-      end
-
-      if lines_count.to_i > 0
-        errors.add(:lines_count, '種類がリダイレクトの場合は 0 である必要があります．')
-      end
-    end
-  end
-end

backend/app/models/wiki_revision_line.rb

@@ -1,8 +0,0 @@
-class WikiRevisionLine < ApplicationRecord
-  belongs_to :wiki_revision
-  belongs_to :wiki_line
-
-  validates :position, presence: true,
-                       numericality: { only_integer: true, greater_than_or_equal_to: 0 }
-  validates :position, uniqueness: { scope: :wiki_revision_id }
-end

backend/app/models/wiki_version.rb

@@ -1,8 +0,0 @@
-class WikiVersion < ApplicationRecord
-  include VersionRecord
-
-  belongs_to :wiki_page
-
-  validates :title, presence: true
-  validates :body, presence: true
-end

backend/app/representations/deerjikist_repr.rb

@@ -1,16 +0,0 @@
-# frozen_string_literal: true
-
-
-module DeerjikistRepr
-  BASE = { only: [:platform, :code], include: { tag: TagRepr::BASE } }.freeze
-
-  module_function
-
-  def base deerjikist
-    deerjikist.as_json(BASE)
-  end
-
-  def many deerjikists
-    deerjikists.map { |d| base(d) }
-  end
-end

backend/app/representations/material_repr.rb

@@ -1,24 +0,0 @@
-# frozen_string_literal: true
-
-
-module MaterialRepr
-  BASE = { only: [:id, :url, :created_at, :updated_at],
-           methods: [:content_type],
-           include: { tag: TagRepr::BASE,
-                      created_by_user: UserRepr::BASE,
-                      updated_by_user: UserRepr::BASE } }.freeze
-
-  module_function
-
-  def base material, host:
-    material.as_json(BASE).merge(
-        file: if material.file.attached?
-                Rails.application.routes.url_helpers.rails_storage_proxy_url(
-                    material.file, host:)
-              end)
-  end
-
-  def many materials, host:
-    materials.map { |m| base(m, host:) }
-  end
-end

backend/app/representations/post_repr.rb

@@ -1,21 +0,0 @@
-# frozen_string_literal: true
-
-
-module PostRepr
-  BASE = { include: { tags: TagRepr::BASE, uploaded_user: UserRepr::BASE },
-           methods: [:parent_posts, :child_posts, :sibling_posts] }.freeze
-
-  module_function
-
-  def base post, current_user = nil
-    json = post.as_json(BASE)
-    return json.merge(viewed: false) unless current_user
-
-    viewed = current_user.viewed?(post)
-    json.merge(viewed:)
-  end
-
-  def many posts, current_user = nil
-    posts.map { |p| base(p, current_user) }
-  end
-end

backend/app/representations/tag_repr.rb

@@ -1,16 +0,0 @@
-# frozen_string_literal: true
-
-
-module TagRepr
-  BASE = { only: [:id, :category, :post_count, :created_at, :updated_at],
-           methods: [:name, :has_wiki, :material_id, :has_deerjikists] }.freeze
-
-  module_function
-
-  def base tag
-    tag.as_json(BASE).merge(aliases: tag.snapshot_aliases,
-                            parents: tag.parents.map { _1.as_json(BASE) })
-  end
-
-  def many(tags) = tags.map { |t| base(t) }
-end

backend/app/representations/theatre_repr.rb

@@ -1,17 +0,0 @@
-# frozen_string_literal: true
-
-
-module TheatreRepr
-  BASE = { only: [:id, :name, :opens_at, :closes_at, :created_at, :updated_at],
-           include: { created_by_user: { only: [:id, :name] } } }.freeze
-
-  module_function
-
-  def base theatre
-    theatre.as_json(BASE)
-  end
-
-  def many theatre
-    theatre.map { |t| base(t) }
-  end
-end

backend/app/representations/user_repr.rb

@@ -1,16 +0,0 @@
-# frozen_string_literal: true
-
-
-module UserRepr
-  BASE = { only: [:id, :name] }.freeze
-
-  module_function
-
-  def base user
-    user.as_json(BASE)
-  end
-
-  def many users
-    users.map { |u| base(u) }
-  end
-end

backend/app/representations/wiki_page_repr.rb

@@ -1,16 +0,0 @@
-# frozen_string_literal: true
-
-
-module WikiPageRepr
-  BASE = { methods: [:title] }.freeze
-
-  module_function
-
-  def base wiki_page
-    wiki_page.as_json(BASE)
-  end
-
-  def many wiki_pages
-    wiki_pages.map { |p| base(p) }
-  end
-end

backend/app/services/nico_tag_version_recorder.rb

@@ -1,19 +0,0 @@
-class NicoTagVersionRecorder < VersionRecorder
-  def self.record! tag:, event_type:, created_by_user:
-    new(tag:, event_type:, created_by_user:).record!
-  end
-
-  def initialize tag:, event_type:, created_by_user:
-    super(record: tag, event_type:, created_by_user:)
-  end
-
-  private
-
-  def version_class = NicoTagVersion
-  def version_association = :nico_tag_versions
-  def record_key = :tag
-
-  def snapshot_attributes
-    { name: @record.name, linked_tags: @record.snapshot_linked_tag_names.join(' ') }
-  end
-end

backend/app/services/post_version_recorder.rb

@@ -1,31 +0,0 @@
-class PostVersionRecorder < VersionRecorder
-  def self.record! post:, event_type:, created_by_user:
-    new(post:, event_type:, created_by_user:).record!
-  end
-
-  def initialize post:, event_type:, created_by_user:
-    super(record: post, event_type:, created_by_user:)
-  end
-
-  def self.ensure_snapshot! post, created_by_user:
-    return if post.post_versions.exists?
-
-    record!(post:, event_type: :create, created_by_user:)
-  end
-
-  private
-
-  def version_class = PostVersion
-  def version_association = :post_versions
-  def record_key = :post
-
-  def snapshot_attributes
-    { title: @record.title,
-      url: @record.url,
-      thumbnail_base: @record.thumbnail_base,
-      tags: @record.snapshot_tag_names.join(' '),
-      parent_post_ids: @record.snapshot_parent_post_ids.join(' '),
-      original_created_from: @record.original_created_from,
-      original_created_before: @record.original_created_before }
-  end
-end

backend/app/services/similarity/calc.rb

@@ -1,106 +0,0 @@
-module Similarity
-  class Calc
-    def self.call model, tgt
-      similarity_model = "#{ model.name }Similarity".constantize
-
-      # 最大保存件数
-      n = 20
-
-      similarity_model.delete_all
-
-      posts = model.includes(tgt).select(:id).to_a
-
-      tag_ids = { }
-      tag_cnts = { }
-
-      posts.each do |p|
-        arr = p.public_send(tgt).map(&:id).sort
-        tag_ids[p.id] = arr
-        tag_cnts[p.id] = arr.size
-      end
-
-      intersection_size = -> a, b do
-        i = 0
-        j = 0
-        cnt = 0
-        while i < a.size && j < b.size
-          a_i = a[i]
-          b_j = b[j]
-          if a_i == b_j
-            cnt += 1
-            i += 1
-            j += 1
-          elsif a_i < b_j
-            i += 1
-          else
-            j += 1
-          end
-        end
-        cnt
-      end
-
-      push_topk = -> list, cos, target_id do
-        return if list.size >= n && cos <= list[-1][0]
-
-        idx = nil
-        list.each_with_index do |(c, tid), i|
-          if tid == target_id
-            idx = i
-            break
-          end
-        end
-        if idx
-          return if cos <= list[idx][0]
-          list.delete_at(idx)
-        end
-
-        insert_at = list.size
-        list.each_with_index do |(c, _), i|
-          if cos > c
-            insert_at = i
-            break
-          end
-        end
-        list.insert(insert_at, [cos, target_id])
-        list.pop if list.size > n
-      end
-
-      top = Hash.new { |h, key| h[key] = [] }
-
-      ids = posts.map(&:id)
-      ids.each_with_index do |post_id, i|
-        a = tag_ids[post_id]
-        a_cnt = tag_cnts[post_id]
-
-        ((i + 1)...ids.size).each do |j|
-          target_id = ids[j]
-          b = tag_ids[target_id]
-          b_cnt = tag_cnts[target_id]
-
-          norm = Math.sqrt(a_cnt * b_cnt)
-          cos = norm.zero? ? 0.0 : intersection_size.(a, b).fdiv(norm)
-
-          push_topk.(top[post_id], cos, target_id)
-          push_topk.(top[target_id], cos, post_id)
-        end
-      end
-
-      buf = []
-      flush = -> do
-        return if buf.empty?
-        similarity_model.insert_all!(buf)
-        buf.clear
-      end
-
-      top.each do |post_id, list|
-        list.each do |cos, target_post_id|
-          buf << { "#{ model.name.underscore }_id".to_sym => post_id,
-                   "target_#{ model.name.underscore }_id".to_sym => target_post_id,
-                   cos: }
-          flush.call if buf.size >= 1_000
-        end
-      end
-      flush.call
-    end
-  end
-end

backend/app/services/tag_version_recorder.rb

@@ -1,22 +0,0 @@
-class TagVersionRecorder < VersionRecorder
-  def self.record! tag:, event_type:, created_by_user:
-    new(tag:, event_type:, created_by_user:).record!
-  end
-
-  def initialize tag:, event_type:, created_by_user:
-    super(record: tag, event_type:, created_by_user:)
-  end
-
-  private
-
-  def version_class = TagVersion
-  def version_association = :tag_versions
-  def record_key = :tag
-
-  def snapshot_attributes
-    { name: @record.name,
-      category: @record.category,
-      aliases: @record.snapshot_aliases.join(' '),
-      parent_tag_ids: @record.snapshot_parent_tag_ids.join(' ') }
-  end
-end

backend/app/services/tag_versioning.rb

@@ -1,38 +0,0 @@
-class TagVersioning
-  def self.record! tag, event_type:, created_by_user:
-    if tag.nico?
-      NicoTagVersionRecorder.record!(tag:, event_type:, created_by_user:)
-    else
-      TagVersionRecorder.record!(tag:, event_type:, created_by_user:)
-    end
-  end
-
-  def self.ensure_snapshot! tag, created_by_user:
-    if tag.nico?
-      return if tag.nico_tag_versions.exists?
-
-      NicoTagVersionRecorder.record!(tag:, event_type: :create, created_by_user:)
-    else
-      return if tag.tag_versions.exists?
-
-      TagVersionRecorder.record!(tag:, event_type: :create, created_by_user:)
-    end
-  end
-
-  def self.record_tag_snapshot! tag, created_by_user:
-    event_type =
-        if tag.nico?
-          tag.nico_tag_versions.exists? ? :update : :create
-        else
-          tag.tag_versions.exists? ? :update : :create
-        end
-
-    record!(tag, event_type:, created_by_user:)
-  end
-
-  def self.record_tag_snapshots! tags, created_by_user:
-    tags.each do |tag|
-      record_tag_snapshot!(tag, created_by_user:)
-    end
-  end
-end

backend/app/services/version_recorder.rb

@@ -1,87 +0,0 @@
-class VersionRecorder
-  EVENT_TYPES = ['create', 'update', 'discard', 'restore'].freeze
-
-  def initialize record:, event_type:, created_by_user:
-    @record = record
-    @event_type = event_type.to_s
-    @created_by_user = created_by_user
-
-    validate_event_type!
-  end
-
-  def record!
-    raise "#{ record_class.name } must be persisted" unless @record.persisted?
-
-    ApplicationRecord.transaction do
-      @record = record_class.unscoped.lock.find(@record.id)
-      latest = latest_version
-
-      validate_version_sequence!(latest)
-
-      attrs = snapshot_attributes
-
-      if @event_type == 'update' && latest && same_snapshot?(latest, attrs)
-        return latest
-      end
-
-      version = version_class.create!(
-          base_attributes(latest).merge(record_key => @record).merge(attrs))
-
-      update_record_version_no!(version.version_no)
-
-      version
-    end
-  end
-
-  private
-
-  def latest_version = versions.order(version_no: :desc).first
-
-  def versions = @record.public_send(version_association)
-
-  def base_attributes latest
-    { version_no: (latest&.version_no || 0) + 1,
-      event_type: @event_type,
-      created_at: Time.current,
-      created_by_user: @created_by_user }
-  end
-
-  def update_record_version_no! version_no
-    @record.update_columns(version_no:)
-    @record.version_no = version_no
-  end
-
-  def validate_version_sequence! latest
-    if !(latest) && @event_type != 'create'
-      raise "#{ version_class.name } first event must be create"
-    end
-
-    if @event_type == 'create' && latest
-      raise "#{ version_class.name } create event already exists"
-    end
-
-    return unless latest
-
-    if @record.version_no != latest.version_no
-      raise ("#{ record_class.name }##{ @record.id } version_no is #{ @record.version_no }, " +
-             "but latest #{ version_class.name } version_no is #{ latest.version_no }")
-    end
-  end
-
-  def same_snapshot? version, attrs
-    attrs.all? { |k, v| version.public_send(k) == v }
-  end
-
-  def validate_event_type!
-    return if EVENT_TYPES.include?(@event_type)
-
-    raise ArgumentError, "Invalid event_type: #{ @event_type }"
-  end
-
-  def version_class = raise NotImplementedError
-  def version_association = raise NotImplementedError
-  def record_key = raise NotImplementedError
-  def snapshot_attributes = raise NotImplementedError
-
-  def record_class = @record.class
-end

backend/app/services/wiki/commit.rb

@@ -1,141 +0,0 @@
-require 'digest'
-
-
-module Wiki
-  class Commit
-    class Conflict < StandardError
-      ;
-    end
-
-    def self.create_content! tag_name:, body:, created_by_user:, message: nil
-      normalised = normalise_body(body)
-
-      page = WikiPage.new(tag_name:,
-                          body: normalised,
-                          created_user: created_by_user,
-                          updated_user: created_by_user)
-
-      if normalised.blank?
-        page.errors.add(:body, :blank)
-        raise ActiveRecord::RecordInvalid, page
-      end
-
-      ActiveRecord::Base.transaction do
-        page.save!
-
-        new(page:, created_user: created_by_user).content!(
-            body: normalised,
-            message:,
-            base_revision_id: nil)
-
-        page
-      end
-    end
-
-    def self.content! page:, body:, created_user:, message: nil, base_revision_id: nil
-      new(page:, created_user:).content!(body:, message:, base_revision_id:)
-    end
-
-    def self.redirect! page:, redirect_page:, created_user:, message: nil, base_revision_id: nil
-      new(page:, created_user:).redirect!(redirect_page:, message:, base_revision_id:)
-    end
-
-    def initialize page:, created_user:
-      @page = page
-      @created_user = created_user
-    end
-
-    def content! body:, message:, base_revision_id:
-      normalised = self.class.normalise_body(body)
-      if normalised.blank?
-        @page.errors.add(:body, :blank)
-        raise ActiveRecord::RecordInvalid, @page
-      end
-
-      lines = split_lines(normalised)
-
-      line_shas = lines.map { |line| Digest::SHA256.hexdigest(line) }
-      tree_sha = Digest::SHA256.hexdigest(line_shas.join(','))
-
-      line_id_by_sha = upsert_lines!(lines, line_shas)
-      line_ids = line_shas.map { |sha| line_id_by_sha.fetch(sha) }
-
-      ActiveRecord::Base.transaction do
-        @page.lock!
-
-        if base_revision_id.present?
-          current_id = @page.wiki_revisions.maximum(:id)
-          if current_id && current_id != base_revision_id.to_i
-            raise Conflict,
-                "競合が発生してゐます" +
-                "（現在の Id.：#{ current_id }，ベース Id.：#{ base_revision_id }）．"
-          end
-        end
-
-        @page.update!(body: normalised)
-
-        WikiVersionRecorder.record!(
-            page: @page,
-            event_type: @page.wiki_versions.exists? ? :update : :create,
-            reason: message,
-            created_by_user: @created_user)
-
-        rev = WikiRevision.create!(
-            wiki_page:        @page,
-            base_revision_id:,
-            created_user:     @created_user,
-            kind:             :content,
-            redirect_page_id: nil,
-            message:,
-            lines_count:      lines.length,
-            tree_sha256:      tree_sha)
-
-        rows = line_ids.each_with_index.map do |line_id, pos|
-          { wiki_revision_id: rev.id, wiki_line_id: line_id, position: pos }
-        end
-        WikiRevisionLine.insert_all!(rows) if rows.any?
-
-        rev
-      end
-    end
-
-    def redirect!(redirect_page:, message:, base_revision_id:) = raise '廃止しました．'
-
-    def self.normalise_body body
-      s = body.to_s
-      s.gsub!(/\r\n?/, "\n")
-      s.encode('UTF-8', invalid: :replace, undef: :replace, replace: '🖕')
-      s.gsub(/\n+$/, '')
-    end
-
-    private
-
-    def split_lines(body) = body.split("\n")
-
-    def upsert_lines! lines, line_shas
-      now = Time.current
-
-      id_by_sha = WikiLine.where(sha256: line_shas).pluck(:sha256, :id).to_h
-
-      missing_by_sha = { }
-
-      line_shas.each_with_index do |sha, i|
-        next if id_by_sha.key?(sha)
-        next if missing_by_sha.key?(sha)
-
-        missing_by_sha[sha] = {
-            sha256:     sha,
-            body:       lines[i],
-            created_at: now,
-            updated_at: now }
-      end
-
-      if missing_by_sha.any?
-        WikiLine.upsert_all(missing_by_sha.values)
-        id_by_sha = WikiLine.where(sha256: line_shas).pluck(:sha256, :id).to_h
-      end
-
-      id_by_sha
-    end
-  end
-end

backend/app/services/wiki_version_recorder.rb

@@ -1,21 +0,0 @@
-class WikiVersionRecorder < VersionRecorder
-  def self.record! page:, event_type:, reason: nil, created_by_user:
-    new(page:, event_type:, reason:, created_by_user:).record!
-  end
-
-  def initialize page:, event_type:, reason: nil, created_by_user:
-    @reason = reason
-    super(record: page, event_type:, created_by_user:)
-  end
-
-  private
-
-  def version_class = WikiVersion
-  def version_association = :wiki_versions
-  def record_key = :wiki_page
-
-  def snapshot_attributes = {
-      title: @record.title,
-      body: @record.body,
-      reason: @reason }
-end

backend/app/services/youtube/api_client.rb

@@ -1,73 +0,0 @@
-require 'json'
-require 'net/http'
-require 'uri'
-
-
-module Youtube
-  class ApiClient
-    ENDPOINT = 'https://www.googleapis.com/youtube/v3'
-
-    def initialize api_key: ENV.fetch('YOUTUBE_API_KEY')
-      @api_key = api_key
-    end
-
-    def search_videos q:, published_after: nil, published_before: nil, page_token: nil
-      get_json('/search', {
-          part:           'snippet',
-          type:           'video',
-          q:,
-          order:          'date',
-          maxResults:     50,
-          regionCode:     'JP',
-          relevanceLanguage: 'ja',
-          publishedAfter: published_after&.iso8601,
-          publishedBefore: published_before&.iso8601,
-          pageToken:      page_token }.compact)
-    end
-
-    def videos ids
-      return { 'items' => [] } if ids.empty?
-
-      get_json('/videos', part: 'snippet,status,contentDetails', id: ids.join(','))
-    end
-
-    def playlist_items playlist_id:, page_token: nil
-      get_json('/playlistItems', {
-          part:       'snippet,contentDetails,status',
-          playlistId: playlist_id,
-          maxResults: 50,
-          pageToken:  page_token }.compact)
-    end
-
-    def channel id: nil, handle: nil
-      raise ArgumentError, 'id or handle is required' if id.present? == handle.present?
-
-      params = { part: 'snippet,contentDetails' }
-      params[:id] = id if id.present?
-      params[:forHandle] = handle if handle.present?
-
-      get_json('/channels', params)
-    end
-
-    private
-
-    def get_json path, params
-      uri = URI(ENDPOINT + path)
-      uri.query = URI.encode_www_form(params.merge(key: @api_key))
-
-      response = Net::HTTP.start(uri.host,
-                                 uri.port,
-                                 use_ssl: true,
-                                 open_timeout: 10,
-                                 read_timeout: 30) do |http|
-        http.get(uri)
-      end
-
-      unless response.is_a?(Net::HTTPSuccess)
-        raise "YouTube API error: #{ response.code } #{ response.body }"
-      end
-
-      JSON.parse(response.body)
-    end
-  end
-end

backend/app/services/youtube/sync.rb

@@ -1,168 +0,0 @@
-require 'open-uri'
-require 'set'
-require 'time'
-
-
-module Youtube
-  class Sync
-    def initialize client: ApiClient.new
-      @client = client
-    end
-
-    def sync!
-      video_ids = discover_video_ids
-      return if video_ids.empty?
-
-      video_ids.each_slice(50) do |ids|
-        @client.videos(ids).fetch('items', []).each do |item|
-          sync_video!(VideoItem.new(item))
-        end
-      end
-    end
-
-    private
-
-    def discover_video_ids
-      ids = Set.new
-
-      query_terms.each do |q|
-        response = @client.search_videos(q:, published_after: sync_since)
-
-        response.fetch('items', []).each do |item|
-          video_id = item.dig('id', 'videoId')
-          ids << video_id if video_id.present?
-        end
-      end
-
-      playlist_ids.each do |playlist_id|
-        each_playlist_item(playlist_id) do |item|
-          video_id = item.dig('contentDetails', 'videoId')
-          video_id ||= item.dig('snippet', 'resourceId', 'videoId')
-
-          ids << video_id if video_id.present?
-        end
-      end
-
-      ids.to_a
-    end
-
-    def sync_video! video
-      post = Post.where('url REGEXP ?', youtube_url_regexp(video.id)).first
-
-      original_created_from = video.published_at.change(sec: 0)
-      original_created_before = original_created_from + 1.minute
-
-      post_created = false
-      post_changed = false
-
-      if post
-        post.assign_attributes(title: video.title,
-                               original_created_from:,
-                               original_created_before:,
-                               thumbnail_base: video.thumbnail_url)
-
-        post_changed = post.changed?
-        post.save! if post_changed
-
-        attach_thumbnail_if_needed!(post, video.thumbnail_url)
-      else
-        post_created = true
-        post = Post.create!(
-            title: video.title,
-            url: video.url,
-            thumbnail_base: video.thumbnail_url,
-            uploaded_user_id: nil,
-            original_created_from:,
-            original_created_before:)
-
-        attach_thumbnail_if_needed!(post, video.thumbnail_url)
-
-        sync_post_tags!(post, [Tag.tagme.id, Tag.bot.id, Tag.youtube.id, Tag.video.id])
-      end
-
-      kept_tag_ids = post.tags.pluck(:id).to_set
-      desired_tag_ids = kept_tag_ids.to_a
-
-      deerjikist = Deerjikist.find_by(platform: :youtube, code: video.channel_id)
-      if deerjikist
-        desired_tag_ids.delete(Tag.no_deerjikist.id)
-        desired_tag_ids << deerjikist.tag_id
-      elsif post.tags.where(category: :deerjikist).none?
-        desired_tag_ids << Tag.no_deerjikist.id
-      end
-
-      desired_tag_ids.uniq!
-
-      sync_post_tags!(post, desired_tag_ids, current_tag_ids: kept_tag_ids)
-
-      if post_created
-        PostVersionRecorder.record!(post:, event_type: :create, created_by_user: nil)
-      elsif post_changed || kept_tag_ids != desired_tag_ids.to_set
-        PostVersionRecorder.ensure_snapshot!(post, created_by_user: nil)
-        PostVersionRecorder.record!(post:, event_type: :update, created_by_user: nil)
-      end
-    end
-
-    def sync_post_tags! post, desired_tag_ids, current_tag_ids: nil
-      current_tag_ids ||= PostTag.kept.where(post_id: post.id).pluck(:tag_id).to_set
-      desired_tag_ids = desired_tag_ids.compact.to_set
-
-      to_add = desired_tag_ids - current_tag_ids
-      to_remove = current_tag_ids - desired_tag_ids
-
-      Tag.where(id: to_add.to_a).find_each do |tag|
-        begin
-          PostTag.create!(post:, tag:)
-        rescue ActiveRecord::RecordNotUnique
-          ;
-        end
-      end
-
-      PostTag.where(post_id: post.id, tag_id: to_remove.to_a).kept.find_each do |pt|
-        pt.discard_by!(nil)
-      end
-    end
-
-    def attach_thumbnail_if_needed! post, thumbnail_url
-      return if post.thumbnail.attached?
-      return if thumbnail_url.blank?
-
-      post.thumbnail.attach(
-          io:           URI.open(thumbnail_url),
-          filename:     File.basename(URI.parse(thumbnail_url).path),
-          content_type: 'image/jpeg')
-
-      post.resized_thumbnail!
-    end
-
-    def youtube_url_regexp id
-      escaped = Regexp.escape(id)
-      "(youtube\\.com/watch\\?v=#{ escaped }|youtu\\.be/#{ escaped })([^A-Za-z0-9_-]|$)"
-    end
-
-    def query_terms = ['ぼざろクリーチャーシリーズ', '伊地知ニジカ', '伊地知虹鹿']
-
-    def playlist_ids
-      ['PLrOch4zHkI5vu29b-f9umUQQ4tQkuWLPX',
-       'PLrOch4zHkI5vOK0RaytQq6PbucxQkkL0K',
-       'PLrOch4zHkI5tdwm9vSegiDQJOM-hgpcOC']
-    end
-
-    def sync_since = 14.days.ago
-
-    def each_playlist_item playlist_id
-      page_token = nil
-
-      loop do
-        response = @client.playlist_items(playlist_id:, page_token:)
-
-        response.fetch('items', []).each do |item|
-          yield item
-        end
-
-        page_token = response['nextPageToken']
-        break if page_token.blank?
-      end
-    end
-  end
-end

backend/app/services/youtube/video_item.rb

@@ -1,32 +0,0 @@
-require 'time'
-
-
-module Youtube
-  class VideoItem
-    attr_reader :id, :title, :channel_id, :published_at, :thumbnail_url, :raw_tags
-
-    def initialize item
-      snippet = item.fetch('snippet')
-
-      @id = item.fetch('id')
-      @title = snippet['title']
-      @channel_id = snippet['channelId']
-      @published_at = Time.iso8601(snippet['publishedAt'])
-      @thumbnail_url = pick_thumbnail(snippet['thumbnails'] || { })
-      @raw_tags = snippet['tags'] || []
-    end
-
-    def url = "https://www.youtube.com/watch?v=#{ @id }"
-
-    private
-
-    def pick_thumbnail thumbnails
-      ['maxres', 'standard', 'high', 'medium', 'default'].each do |key|
-        url = thumbnails.dig(key, 'url')
-        return url if url.present?
-      end
-
-      nil
-    end
-  end
-end

backend/config/application.rb

@@ -11,9 +11,6 @@ module Backend
     # Initialize configuration defaults for originally generated Rails version.
     config.load_defaults 8.0
 
-    config.i18n.available_locales = [:ja, :en]
-    config.i18n.default_locale = :ja
-
     # Please, add to the `ignore` list any other `lib` subdirectories that do
     # not contain `.rb` files, or that should not be reloaded or eager loaded.
     # Common ones are `templates`, `generators`, or `middleware`, for example.

backend/config/environments/production.rb

@@ -18,7 +18,8 @@ Rails.application.configure do
   # Enable serving of images, stylesheets, and JavaScripts from an asset server.
   # config.asset_host = "http://assets.example.com"
 
-  config.active_storage.service = :r2
+  # Store uploaded files on the local file system (see config/storage.yml for options).
+  config.active_storage.service = :local
 
   # Assume all access to the app is happening through a SSL-terminating reverse proxy.
   config.assume_ssl = true

backend/config/environments/test.rb

@@ -50,6 +50,4 @@ Rails.application.configure do
 
   # Raise error when a before_action's only/except options reference missing actions.
   config.action_controller.raise_on_missing_callback_actions = true
-
-  Rails.application.routes.default_url_options[:host] = 'www.example.com'
 end

backend/config/locales/en.yml

@@ -28,8 +28,4 @@
 #       enabled: "ON"
 
 en:
-  activerecord:
+  hello: "Hello world"
-    errors:
-      messages:
-        record_invalid: "Validation failed: %{errors}"
-        taken: 'イキスギ!'

backend/config/locales/ja.yml

@@ -1,2 +0,0 @@
-ja:
-  hello: 'ぬ゛〜゛ん゛'

backend/config/routes.rb

@@ -1,30 +1,10 @@
 Rails.application.routes.draw do
   resources :nico_tags, path: 'tags/nico', only: [:index, :update]
 
-  scope 'tags/:parent_id/children', controller: :tag_children do
+  resources :tags do
-    post ':child_id', action: :create
-    delete ':child_id', action: :destroy
-  end
-
-  resources :tags, only: [:index, :show] do
     collection do
       get :autocomplete
-      get :'with-depth', action: :with_depth
+      get 'name/:name', action: :show_by_name
-      get :versions, to: 'tag_versions#index'
-
-      scope :name do
-        get ':name/deerjikists', action: :deerjikists_by_name
-        get ':name/materials', action: :materials_by_name
-        get ':name', action: :show_by_name
-      end
-    end
-
-    member do
-      put '', action: :update_all
-      patch '', action: :update
-
-      get :deerjikists
-      put :deerjikists, action: :update_deerjikists
     end
   end
 
@@ -50,11 +30,10 @@ Rails.application.routes.draw do
     end
   end
 
-  resources :posts, only: [:index, :show, :create, :update] do
+  resources :posts do
     collection do
       get :random
       get :changes
-      get :versions, to: 'post_versions#index'
     end
 
     member do
@@ -71,24 +50,11 @@ Rails.application.routes.draw do
     end
   end
 
-  resources :deerjikists, only: [] do
+  resources :ip_addresses
-    collection do
+  resources :nico_tag_relations
-      scope ':platform/:code' do
+  resources :post_tags
-        get '', action: :show
+  resources :settings
-        put '', action: :update
+  resources :tag_aliases
-        delete '', action: :destroy
+  resources :user_ips
-      end
+  resources :user_post_views
-    end
-  end
-
-  resources :theatres, only: [:show] do
-    member do
-      put :watching
-      patch :next_post
-    end
-
-    resources :comments, controller: :theatre_comments, only: [:index, :create]
-  end
-
-  resources :materials, only: [:index, :show, :create, :update, :destroy]
 end

backend/config/schedule.rb

@@ -1,27 +1,12 @@
 env :PATH, '/root/.rbenv/shims:/root/.rbenv/bin:/usr/local/bin:/usr/bin:/bin'
 
-set :path, '/var/www/btrc-hub/backend'
-set :environment, 'production'
 set :output, standard: '/var/log/btrc_hub_nico_sync.log',
              error:    '/var/log/btrc_hub_nico_sync_err.log'
 
-job_type :rake,
+every 1.day, at: '3:00 pm' do
-         'cd :path && set -a && . /etc/btrc-hub/backend.env && set +a && ' \
-         ':environment_variable=:environment bundle exec rake :task --silent :output'
-
-every 1.day, at: '11:00 am' do
   rake 'nico:sync', environment: 'production'
 end
 
 every 1.day, at: '0:00 am' do
   rake 'post_similarity:calc', environment: 'production'
-  rake 'tag_similarity:calc', environment: 'production'
-end
-
-every 1.day, at: '7:50 am' do
-  rake 'nico:export', environment: 'production'
-end
-
-every :hour do
-  rake 'post:sync', environment: 'production'
 end

backend/config/storage.yml

@@ -6,11 +6,29 @@ local:
   service: Disk
   root: <%= Rails.root.join("storage") %>
 
-r2:
+# Use bin/rails credentials:edit to set the AWS secrets (as aws:access_key_id|secret_access_key)
-  service: S3
+# amazon:
-  endpoint: <%= ENV['R2_ENDPOINT'] %>
+#   service: S3
-  access_key_id: <%= ENV['R2_ACCESS_KEY_ID'] %>
+#   access_key_id: <%= Rails.application.credentials.dig(:aws, :access_key_id) %>
-  secret_access_key: <%= ENV['R2_SECRET_ACCESS_KEY'] %>
+#   secret_access_key: <%= Rails.application.credentials.dig(:aws, :secret_access_key) %>
-  bucket: <%= ENV['R2_BUCKET'] %>
+#   region: us-east-1
-  region: auto
+#   bucket: your_own_bucket-<%= Rails.env %>
-  request_checksum_calculation: when_required
+
+# Remember not to checkin your GCS keyfile to a repository
+# google:
+#   service: GCS
+#   project: your_project
+#   credentials: <%= Rails.root.join("path/to/gcs.keyfile") %>
+#   bucket: your_own_bucket-<%= Rails.env %>
+
+# Use bin/rails credentials:edit to set the Azure Storage secret (as azure_storage:storage_access_key)
+# microsoft:
+#   service: AzureStorage
+#   storage_account_name: your_account_name
+#   storage_access_key: <%= Rails.application.credentials.dig(:azure_storage, :storage_access_key) %>
+#   container: your_container_name-<%= Rails.env %>
+
+# mirror:
+#   service: Mirror
+#   primary: local
+#   mirrors: [ amazon, google, microsoft ]

backend/db/migrate/20251229012100_remove_tag_from_wiki_pages.rb

@@ -1,5 +0,0 @@
-class RemoveTagFromWikiPages < ActiveRecord::Migration[7.0]
-  def change
-    remove_reference :wiki_pages, :tag, if_exists: true
-  end
-end

backend/db/migrate/20251229020700_create_wiki_lines.rb

@@ -1,11 +0,0 @@
-class CreateWikiLines < ActiveRecord::Migration[7.0]
-  def change
-    create_table :wiki_lines do |t|
-      t.string :sha256, null: false, limit: 64
-      t.text :body, null: false
-      t.timestamps
-    end
-
-    add_index :wiki_lines, :sha256, unique: true
-  end
-end

backend/db/migrate/20251229021000_create_wiki_revisions.rb

@@ -1,19 +0,0 @@
-class CreateWikiRevisions < ActiveRecord::Migration[7.0]
-  def change
-    create_table :wiki_revisions do |t|
-      t.references :wiki_page, null: false, foreign_key: true
-      t.references :base_revision, foreign_key: { to_table: :wiki_revisions }
-      t.references :created_user, null: false, foreign_key: { to_table: :users }
-      t.integer :kind, null: false, default: 0  # 0: content, 1: redirect
-      t.references :redirect_page, foreign_key: { to_table: :wiki_pages }
-      t.string :message
-      t.integer :lines_count, null: false, default: 0
-      t.string :tree_sha256, limit: 64
-      t.timestamps
-    end
-
-    add_index :wiki_revisions, :tree_sha256
-    add_index :wiki_revisions, [:wiki_page_id, :id]
-    add_index :wiki_revisions, :kind
-  end
-end

backend/db/migrate/20251229022100_create_wiki_revision_lines.rb

@@ -1,12 +0,0 @@
-class CreateWikiRevisionLines < ActiveRecord::Migration[7.0]
-  def change
-    create_table :wiki_revision_lines do |t|
-      t.references :wiki_revision, null: false, foreign_key: true
-      t.integer :position, null: false
-      t.references :wiki_line, null: false, foreign_key: true
-    end
-
-    add_index :wiki_revision_lines, [:wiki_revision_id, :position], unique: true
-    add_index :wiki_revision_lines, [:wiki_revision_id, :wiki_line_id]
-  end
-end

backend/db/migrate/20251230143400_make_thumbnail_base_nullable_in_posts.rb

@@ -1,27 +0,0 @@
-class MakeThumbnailBaseNullableInPosts < ActiveRecord::Migration[7.0]
-  def up
-    change_column_null :posts, :thumbnail_base, true
-
-    execute <<~SQL
-      UPDATE
-        posts
-      SET
-        thumbnail_base = NULL
-      WHERE
-        thumbnail_base = ''
-    SQL
-  end
-
-  def down
-    execute <<~SQL
-      UPDATE
-        posts
-      SET
-        thumbnail_base = ''
-      WHERE
-        thumbnail_base IS NULL
-    SQL
-
-    change_column_null :posts, :thumbnail_base, false
-  end
-end

backend/db/migrate/20260107034300_make_title_nullable_in_posts.rb

@@ -1,28 +0,0 @@
-class MakeTitleNullableInPosts < ActiveRecord::Migration[7.0]
-  def up
-    change_column_null :posts, :title, true
-
-    execute <<~SQL
-      UPDATE
-        posts
-      SET
-        title = NULL
-      WHERE
-        title = ''
-    SQL
-  end
-
-  def down
-    execute <<~SQL
-      UPDATE
-        posts
-      SET
-        title = ''
-      WHERE
-        title IS NULL
-    SQL
-
-    change_column_null :posts, :title, false
-  end
-end
-

backend/db/migrate/20260111180600_create_tag_names.rb

@@ -1,10 +0,0 @@
-class CreateTagNames < ActiveRecord::Migration[7.0]
-  def change
-    create_table :tag_names do |t|
-      t.string :name, limit: 255, null: false
-      t.references :canonical, null: true, foreign_key: { to_table: :tag_names }, index: true
-      t.timestamps
-    end
-    add_index :tag_names, :name, unique: true
-  end
-end

backend/db/migrate/20260111192600_add_tag_name_to_tags.rb

@@ -1,42 +0,0 @@
-class AddTagNameToTags < ActiveRecord::Migration[7.0]
-  class Tag < ApplicationRecord
-    self.table_name = 'tags'
-  end
-
-  class TagName < ApplicationRecord
-    self.table_name = 'tag_names'
-  end
-
-  def up
-    add_reference :tags, :tag_name, null: true, foreign_key: true, index: false, after: :id
-    add_index :tags, :tag_name_id, unique: true
-
-    Tag.find_each do |tag|
-      name = tag.read_attribute(:name)
-      tn = TagName.find_or_create_by!(name:) do |r|
-        r.canonical_id = nil
-      end
-      tag.update_columns(tag_name_id: tn.id)
-    end
-
-    change_column_null :tags, :tag_name_id, false
-
-    remove_column :tags, :name
-  end
-
-  def down
-    add_column :tags, :name, :string, limit: 255, null: true, after: :id
-
-    Tag.find_each do |tag|
-      tag_name_id = tag.read_attribute(:tag_name_id)
-      name = TagName.find(tag_name_id).read_attribute(:name)
-      tag.update_columns(name:)
-    end
-
-    change_column_null :tags, :name, false
-
-    remove_foreign_key :tags, column: :tag_name_id
-    remove_index :tags, :tag_name_id
-    remove_column :tags, :tag_name_id
-  end
-end

backend/db/migrate/20260111204400_add_tag_name_to_wiki_pages.rb

@@ -1,42 +0,0 @@
-class AddTagNameToWikiPages < ActiveRecord::Migration[7.0]
-  class WikiPage < ApplicationRecord
-    self.table_name = 'wiki_pages'
-  end
-
-  class TagName < ApplicationRecord
-    self.table_name = 'tag_names'
-  end
-
-  def up
-    add_reference :wiki_pages, :tag_name, null: true, foreign_key: true, index: false, after: :id
-    add_index :wiki_pages, :tag_name_id, unique: true
-
-    WikiPage.find_each do |page|
-      name = page.read_attribute(:title)
-      tn = TagName.find_or_create_by!(name:) do |r|
-        r.canonical_id = nil
-      end
-      page.update_columns(tag_name_id: tn.id)
-    end
-
-    change_column_null :wiki_pages, :tag_name_id, false
-
-    remove_column :wiki_pages, :title
-  end
-
-  def down
-    add_column :wiki_pages, :title, :string, limit: 255, null: true, after: :id
-
-    WikiPage.find_each do |page|
-      tag_name_id = page.read_attribute(:tag_name_id)
-      title = TagName.find(tag_name_id).read_attribute(:name)
-      page.update_columns(title:)
-    end
-
-    change_column_null :wiki_pages, :title, false
-
-    remove_foreign_key :wiki_pages, column: :tag_name_id
-    remove_index :wiki_pages, :tag_name_id
-    remove_column :wiki_pages, :tag_name_id
-  end
-end

backend/db/migrate/20260112111800_drop_tag_aliases.rb

@@ -1,9 +0,0 @@
-class DropTagAliases < ActiveRecord::Migration[7.0]
-  def up
-    drop_table :tag_aliases
-  end
-
-  def down
-    raise ActiveRecord::IrreversibleMigration, '戻せません．'
-  end
-end

backend/db/migrate/20260118144400_add_unique_index_to_url_in_posts.rb

@@ -1,6 +0,0 @@
-class AddUniqueIndexToUrlInPosts < ActiveRecord::Migration[7.1]
-  def change
-    change_column :posts, :url, :string, limit: 768
-    add_index :posts, :url, unique: true, name: 'index_posts_on_url'
-  end
-end

backend/db/migrate/20260121024000_change_post_similarities_to_composite_pk.rb

@@ -1,43 +0,0 @@
-class ChangePostSimilaritiesToCompositePk < ActiveRecord::Migration[8.0]
-  def up
-    execute <<~SQL
-      ALTER TABLE
-        post_similarities
-          MODIFY COLUMN id BIGINT NOT NULL
-      ;
-    SQL
-
-    execute <<~SQL
-      ALTER TABLE
-        post_similarities
-          DROP PRIMARY KEY
-      ;
-    SQL
-
-    remove_column :post_similarities, :id
-
-    execute <<~SQL
-      ALTER TABLE
-        post_similarities
-          ADD PRIMARY KEY (post_id, target_post_id)
-      ;
-    SQL
-  end
-
-  def down
-    execute <<~SQL
-      ALTER TABLE
-        post_similarities
-          DROP PRIMARY KEY
-      ;
-    SQL
-
-    execute <<~SQL
-      ALTER TABLE
-        post_similarities
-          ADD COLUMN id BIGINT NOT NULL AUTO_INCREMENT FIRST
-        , ADD PRIMARY KEY (id)
-      ;
-    SQL
-  end
-end

backend/db/migrate/20260121024800_change_tag_similarities_to_composite_pk.rb

@@ -1,43 +0,0 @@
-class ChangeTagSimilaritiesToCompositePk < ActiveRecord::Migration[8.0]
-  def up
-    execute <<~SQL
-      ALTER TABLE
-        tag_similarities
-          MODIFY COLUMN id BIGINT NOT NULL
-      ;
-    SQL
-
-    execute <<~SQL
-      ALTER TABLE
-        tag_similarities
-          DROP PRIMARY KEY
-      ;
-    SQL
-
-    remove_column :tag_similarities, :id
-
-    execute <<~SQL
-      ALTER TABLE
-        tag_similarities
-          ADD PRIMARY KEY (tag_id, target_tag_id)
-      ;
-    SQL
-  end
-
-  def down
-    execute <<~SQL
-      ALTER TABLE
-        tag_similarities
-          DROP PRIMARY KEY
-      ;
-    SQL
-
-    execute <<~SQL
-      ALTER TABLE
-        tag_similarities
-          ADD COLUMN id BIGINT NOT NULL AUTO_INCREMENT FIRST
-        , ADD PRIMARY KEY (id)
-      ;
-    SQL
-  end
-end

backend/db/migrate/20260121213900_add_index_to_post_similarities.rb

@@ -1,9 +0,0 @@
-class AddIndexToPostSimilarities < ActiveRecord::Migration[8.0]
-  def change
-    remove_index :post_similarities, name: 'index_post_similarities_on_post_id'
-
-    add_index :post_similarities, [:post_id, :cos],
-              order: { cos: :desc },
-              name: 'index_post_similarities_on_post_id_and_cos'
-  end
-end

backend/db/migrate/20260121225600_add_index_to_tag_similarities.rb

@@ -1,9 +0,0 @@
-class AddIndexToTagSimilarities < ActiveRecord::Migration[8.0]
-  def change
-    remove_index :tag_similarities, name: 'index_tag_similarities_on_tag_id'
-
-    add_index :tag_similarities, [:tag_id, :cos],
-              order: { cos: :desc },
-              name: 'index_tag_similarities_on_tag_id_and_cos'
-  end
-end

backend/db/migrate/20260126124100_add_unique_index_to_ip_addresses.rb

@@ -1,5 +0,0 @@
-class AddUniqueIndexToIpAddresses < ActiveRecord::Migration[8.0]
-  def change
-    add_index :ip_addresses, :ip_address, unique: true, name: 'index_ip_addresses_on_ip_address'
-  end
-end

backend/db/migrate/20260127000900_change_user_ips_to_composite_pk.rb

@@ -1,47 +0,0 @@
-class ChangeUserIpsToCompositePk < ActiveRecord::Migration[8.0]
-  def up
-    execute <<~SQL
-      ALTER TABLE
-        user_ips
-          MODIFY COLUMN id BIGINT NOT NULL
-      ;
-    SQL
-
-    execute <<~SQL
-      ALTER TABLE
-        user_ips
-          DROP PRIMARY KEY
-      ;
-    SQL
-
-    remove_column :user_ips, :id
-
-    execute <<~SQL
-      ALTER TABLE
-        user_ips
-          ADD PRIMARY KEY (user_id, ip_address_id)
-      ;
-    SQL
-
-    remove_index :user_ips, name: 'index_user_ips_on_user_id'
-  end
-
-  def down
-    execute <<~SQL
-      ALTER TABLE
-        user_ips
-          DROP PRIMARY KEY
-      ;
-    SQL
-
-    execute <<~SQL
-      ALTER TABLE
-        user_ips
-          ADD COLUMN id BIGINT NOT NULL AUTO_INCREMENT FIRST
-        , ADD PRIMARY KEY (id)
-      ;
-    SQL
-
-    add_index :user_ips, :user_id, name: 'index_user_ips_on_user_id'
-  end
-end

backend/db/migrate/20260127005300_change_user_post_views_to_composite_pk.rb

@@ -1,47 +0,0 @@
-class ChangeUserPostViewsToCompositePk < ActiveRecord::Migration[8.0]
-  def up
-    execute <<~SQL
-      ALTER TABLE
-        user_post_views
-          MODIFY COLUMN id BIGINT NOT NULL
-      ;
-    SQL
-
-    execute <<~SQL
-      ALTER TABLE
-        user_post_views
-          DROP PRIMARY KEY
-      ;
-    SQL
-
-    remove_column :user_post_views, :id
-
-    execute <<~SQL
-      ALTER TABLE
-        user_post_views
-          ADD PRIMARY KEY (user_id, post_id)
-      ;
-    SQL
-
-    remove_index :user_post_views, name: 'index_user_post_views_on_user_id'
-  end
-
-  def down
-    execute <<~SQL
-      ALTER TABLE
-        user_post_views
-          DROP PRIMARY KEY
-      ;
-    SQL
-
-    execute <<~SQL
-      ALTER TABLE
-        user_post_views
-          ADD COLUMN id BIGINT NOT NULL AUTO_INCREMENT FIRST
-        , ADD PRIMARY KEY (id)
-      ;
-    SQL
-
-    add_index :user_post_views, :user_id, name: 'index_user_post_views_on_user_id'
-  end
-end

backend/db/migrate/20260303122700_create_deerjikists.rb

@@ -1,10 +0,0 @@
-class CreateDeerjikists < ActiveRecord::Migration[8.0]
-  def change
-    create_table :deerjikists, primary_key: [:platform, :code] do |t|
-      t.string :platform, null: false, limit: 16
-      t.string :code, null: false
-      t.references :tag, null: false
-      t.timestamps
-    end
-  end
-end

backend/db/migrate/20260309123200_create_tag_name_sanitisation_rules.rb

@@ -1,31 +0,0 @@
-class CreateTagNameSanitisationRules < ActiveRecord::Migration[8.0]
-  def up
-    create_table :tag_name_sanitisation_rules, id: :integer, primary_key: :priority do |t|
-      t.string :source_pattern, null: false
-      t.string :replacement, null: false
-      t.timestamps
-      t.datetime :discarded_at
-      t.index :source_pattern, unique: true
-      t.index :discarded_at
-    end
-
-    now = ActiveRecord::Base.connection.quote(Time.current)
-    execute <<~SQL
-      INSERT INTO
-        tag_name_sanitisation_rules(priority, source_pattern, replacement, created_at, updated_at)
-      VALUES
-        (10, '\\\\*',           '_',         #{ now }, #{ now })
-      , (20, '\\\\?',           '_',         #{ now }, #{ now })
-      , (25, '\\\\/',           '_',         #{ now }, #{ now })
-      , (30, '_+',              '_',         #{ now }, #{ now })
-      , (40, '_$',              '',          #{ now }, #{ now })
-      , (45, '^([^:]+\\\\:)?_', '\\\\1',     #{ now }, #{ now })
-      , (50, '^([^:]+\\\\:)?$', '\\\\1null', #{ now }, #{ now })
-      ;
-    SQL
-  end
-
-  def down
-    drop_table :tag_name_sanitisation_rules
-  end
-end