From 11eedc242d455338c29bcc4ed3fa2cdccfcda99f Mon Sep 17 00:00:00 2001
From: miteruzo <miteruzo@naver.com>
Date: Sun, 4 Oct 2026 13:45:23 +0900
Subject: [PATCH] #422

---
 .../tag_descriptions_controller.rb            |   0
 .../app/controllers/wiki_pages_controller.rb  | 120 ++++++++++++++++--
 backend/app/models/tag_description.rb         |   3 +
 backend/app/models/tag_description_version.rb |   3 +
 backend/app/models/wiki_page.rb               |  11 +-
 backend/config/routes.rb                      |   2 +-
 .../20261003000000_create_tag_descriptions.rb |  63 +++++++++
 ...igrate_tag_descriptions_from_wiki_pages.rb | 104 +++++++++++++++
 backend/db/schema.rb                          |  67 +++++++---
 9 files changed, 343 insertions(+), 30 deletions(-)
 create mode 100644 backend/app/controllers/tag_descriptions_controller.rb
 create mode 100644 backend/app/models/tag_description.rb
 create mode 100644 backend/app/models/tag_description_version.rb
 create mode 100644 backend/db/migrate/20261003000000_create_tag_descriptions.rb
 create mode 100644 backend/db/migrate/20261003010000_migrate_tag_descriptions_from_wiki_pages.rb

diff --git a/backend/app/controllers/tag_descriptions_controller.rb b/backend/app/controllers/tag_descriptions_controller.rb
new file mode 100644
index 0000000..e69de29
diff --git a/backend/app/controllers/wiki_pages_controller.rb b/backend/app/controllers/wiki_pages_controller.rb
index b0d0b8c..9a0c310 100644
--- a/backend/app/controllers/wiki_pages_controller.rb
+++ b/backend/app/controllers/wiki_pages_controller.rb
@@ -2,21 +2,129 @@ class WikiPagesController < ApplicationController
   rescue_from Wiki::Commit::Conflict, with: :render_wiki_conflict
 
   def index
+    # 互換性のための化石リソース
+    # TODO: ヘルプおよびタグ・グループ追加後に，
+    # TODO: タグ説明とヘルプ、タグ・グループから取得する作りに変更する．
+
     title = params[:title].to_s.strip
     if title.blank?
-      return render json: WikiPageRepr.base(
-          WikiPage.joins(:tag_name).includes(tag_name: :tag))
+      tag_descriptions = TagDescription.where(language_code: :ja).map do |td|
+        { id: td.id,
+          tag_name_id: td.tag.tag_name(:ja).id,
+          body: td.body,
+          created_user_id: td.created_by_user_id,
+          updated_user_id: td.updated_by_user_id,
+          created_at: td.created_at,
+          updated_at: td.updated_at,
+          discarded_at: nil,
+          version_no: td.version_no,
+          title: td.tag.name(:ja),
+          deprecated_at: td.tag.deprecated_at }
+      end
+      # TODO: ヘルプ移行したらここに追記
+      # TODO: タグ・グループ追加したらここに追記
+
+      # TODO: ヘルプ、タグ・グループ移行したらそれらもタイトルから除外に含める．
+      # てかこれ何順?
+      wiki_pages =
+          WikiPageRepr.base(WikiPage.joins(:tag_name).includes(tag_name: :tag))
+          .reject { |wp| tag_descriptions.any? { |td| td.title == wp.title } }
+
+      json = tag_descriptions + wiki_pages
+
+      return render json:
     end
 
-    q = WikiPage.joins(:tag_name).includes(tag_name: :tag)
+    q =
+        TagDescription.joins(tag: :tag_names)
+        .where(language_code: :ja)
+        .where(tag: { tag_names: { language_code: :ja, primary_flg: true } })
+        .where('tag_names.name LIKE ?', "%#{ ApplicationRecord.sanitize_sql_like(title) }%")
+    tag_descriptions = q.limit(20).map do |td|
+      { id: td.id,
+        tag_name_id: td.tag.tag_name(:ja).id,
+        body: td.body,
+        created_user_id: td.created_by_user_id,
+        updated_user_id: td.updated_by_user_id,
+        created_at: td.created_at,
+        updated_at: td.updated_at,
+        discarded_at: nil,
+        version_no: td.version_no,
+        title: td.tag.name(:ja),
+        deprecated_at: td.tag.deprecated_at }
+    end
+
+    q =
+        WikiPage.joins(:tag_name).includes(tag_name: :tag)
         .where('tag_names.name LIKE ?', "%#{ WikiPage.sanitize_sql_like(title) }%")
-    render json: WikiPageRepr.base(q.limit(20))
+    # TODO: ヘルプ、タグ・グループ移行したらそれらもタイトルから除外に含める．
+    wiki_pages =
+        WikiPageRepr.base(q.limit(20))
+        .reject { |wp| tag_descriptions.any? { |td| td.title == wp.title } }
+
+    json = (tag_descriptions + wiki_pages)[...20]
+
+    render json:
   end
 
   def show
+    tag_description = TagDescription.find_by(id: params[:id])
+
+    if tag_description
+      rev =
+          if params[:version].present?
+            TagDescriptionVersion.find_by(id: params[:version])
+          else
+            TagDescriptionVersion.find_by(tag_id: tag_description.tag_id,
+                                          language_code: :ja,
+                                          version_no: tag_description.version_no)
+          end
+
+      if rev
+        body =
+            if rev.version_no == tag_description.version_no
+              tag_description.body
+            else
+              rev.body
+            end
+        revision_id = rev.id
+        pred = TagDescriptionVersion.find_by(tag_id: tag_description.tag_id,
+                                             language_code: :ja,
+                                             version_no: tag_description.version_no - 1)&.id
+        succ = TagDescriptionVersion.find_by(tag_id: tag_description.tag_id,
+                                             language_code: :ja,
+                                             version_no: tag_description.version_no + 1)&.id
+        updated_at =
+            if rev.version_no == tag_description.version_no
+              tag_description.updated_at
+            else
+              rev.created_at
+            end
+
+        json = 
+            { id: tag_description.id,
+              tag_name_id: tag_description.tag.tag_name(:ja).id,
+              body:,
+              created_user_id: tag_description.created_by_user_id,
+              updated_user_id: tag_description.updated_by_user_id,
+              created_at: tag_description.created_at,
+              updated_at:,
+              discarded_at: nil,
+              version_no: tag_description.version_no,
+              title: tag_description.tag.name(:ja),
+              deprecated_at: tag_description.tag.deprecated_at,
+              revision_id:,
+              pred:,
+              succ: }
+
+        return render json:
+      end
+    end
+
     page = WikiPage.joins(:tag_name)
                    .includes(tag_name: :tag)
                    .find_by(id: params[:id])
+
     render_wiki_page_or_404 page
   end
 
@@ -156,10 +264,6 @@ class WikiPagesController < ApplicationController
     head :ok
   end
 
-  def search
-    index
-  end
-
   def changes
     id = params[:id].presence
     q = WikiRevision.joins(wiki_page: :tag_name)
diff --git a/backend/app/models/tag_description.rb b/backend/app/models/tag_description.rb
new file mode 100644
index 0000000..2c5e226
--- /dev/null
+++ b/backend/app/models/tag_description.rb
@@ -0,0 +1,3 @@
+class TagDescription < ApplicationRecord
+  belongs_to :tag
+end
diff --git a/backend/app/models/tag_description_version.rb b/backend/app/models/tag_description_version.rb
new file mode 100644
index 0000000..69f31ac
--- /dev/null
+++ b/backend/app/models/tag_description_version.rb
@@ -0,0 +1,3 @@
+class TagDescriptionVersion < ApplicationRecord
+  ;
+end
diff --git a/backend/app/models/wiki_page.rb b/backend/app/models/wiki_page.rb
index 68928f1..caee630 100644
--- a/backend/app/models/wiki_page.rb
+++ b/backend/app/models/wiki_page.rb
@@ -48,8 +48,11 @@ class WikiPage < ApplicationRecord
     page
   end
 
-  def pred_revision_id(revision_id) =
-      wiki_revisions.where('id < ?', revision_id).order(id: :desc).limit(1).pick(:id)
-  def succ_revision_id(revision_id) =
-      wiki_revisions.where('id > ?', revision_id).order(id: :asc).limit(1).pick(:id)
+  def pred_revision_id revision_id
+    wiki_revisions.where('id < ?', revision_id).order(id: :desc).limit(1).pick(:id)
+  end
+
+  def succ_revision_id revision_id
+    wiki_revisions.where('id > ?', revision_id).order(id: :asc).limit(1).pick(:id)
+  end
 end
diff --git a/backend/config/routes.rb b/backend/config/routes.rb
index 0f721d1..e44f5b5 100644
--- a/backend/config/routes.rb
+++ b/backend/config/routes.rb
@@ -35,7 +35,7 @@ Rails.application.routes.draw do
 
   resources :wiki_pages, path: 'wiki', only: [:index, :show, :create, :update] do
     collection do
-      get :search
+      get :search, to: redirect('/')
       get :changes
 
       scope :title do
diff --git a/backend/db/migrate/20261003000000_create_tag_descriptions.rb b/backend/db/migrate/20261003000000_create_tag_descriptions.rb
new file mode 100644
index 0000000..961a4ad
--- /dev/null
+++ b/backend/db/migrate/20261003000000_create_tag_descriptions.rb
@@ -0,0 +1,63 @@
+class CreateTagDescriptions < ActiveRecord::Migration[8.0]
+  def change
+    create_table :tag_description_versions do |t|
+      t.references :tag, null: false, foreign_key: false
+      t.string :language_code, limit: 16, null: false
+      t.integer :version_no, null: false
+      t.string :event_type, null: false
+      t.text :body, null: false
+      t.string :source_language_code, limit: 16
+      t.integer :source_version_no
+      t.references :created_by_user
+      t.datetime :created_at, null: false
+
+      t.index [:tag_id, :language_code, :version_no], unique: true
+      t.foreign_key :tag_description_versions,
+                    column: [:tag_id, :source_language_code, :source_version_no],
+                    primary_key: [:tag_id, :language_code, :version_no]
+
+      t.check_constraint 'version_no > 0',
+                         name: 'chk_tag_description_versions_version_no_positive'
+
+      t.check_constraint "event_type IN ('create', 'update', 'discard', 'restore')",
+                         name: 'tag_description_versions_event_type_valid'
+
+      t.check_constraint ('(source_language_code IS NULL AND source_version_no IS NULL) OR ' +
+                          '(source_language_code IS NOT NULL AND source_version_no IS NOT NULL)'),
+                         name: 'chk_tag_description_versions_source_pair'
+
+      t.check_constraint 'source_language_code IS NULL OR source_language_code <> language_code',
+                         name: 'chk_tag_description_versions_source_language_code_different'
+    end
+
+    create_table :tag_descriptions do |t|
+      t.references :tag, null: false, foreign_key: true
+      t.string :language_code, limit: 16, null: false, index: true
+      t.integer :version_no, null: false
+      t.text :body, null: false
+      t.string :source_language_code, limit: 16
+      t.integer :source_version_no
+      t.references :created_by_user, foreign_key: { to_table: :users }
+      t.references :updated_by_user, foreign_key: { to_table: :users }
+      t.timestamps
+
+      t.foreign_key :languages, column: :language_code, primary_key: :code
+      t.foreign_key :tag_description_versions,
+                    column: [:tag_id, :source_language_code, :source_version_no],
+                    primary_key: [:tag_id, :language_code, :version_no]
+
+      t.index [:tag_id, :language_code], unique: true
+      t.index [:source_language_code, :source_version_no]
+
+      t.check_constraint 'version_no > 0',
+                         name: 'chk_tag_descriptions_version_no_positive'
+
+      t.check_constraint ('(source_language_code IS NULL AND source_version_no IS NULL) OR ' +
+                          '(source_language_code IS NOT NULL AND source_version_no IS NOT NULL)'),
+                         name: 'chk_tag_descriptions_source_pair'
+
+      t.check_constraint 'source_language_code IS NULL OR source_language_code <> language_code',
+                         name: 'chk_tag_descriptions_source_language_code_different'
+    end
+  end
+end
diff --git a/backend/db/migrate/20261003010000_migrate_tag_descriptions_from_wiki_pages.rb b/backend/db/migrate/20261003010000_migrate_tag_descriptions_from_wiki_pages.rb
new file mode 100644
index 0000000..4d51db9
--- /dev/null
+++ b/backend/db/migrate/20261003010000_migrate_tag_descriptions_from_wiki_pages.rb
@@ -0,0 +1,104 @@
+class MigrateTagDescriptionsFromWikiPages < ActiveRecord::Migration[8.0]
+  class WikiPage < ActiveRecord::Base
+    self.table_name = 'wiki_pages'
+  end
+
+  class WikiRevision < ActiveRecord::Base
+    self.table_name = 'wiki_revisions'
+  end
+
+  class WikiRevisionLine < ActiveRecord::Base
+    self.table_name = 'wiki_revision_lines'
+  end
+
+  class TagName < ActiveRecord::Base
+    self.table_name = 'tag_names'
+  end
+
+  class TagDescription < ActiveRecord::Base
+    self.table_name = 'tag_descriptions'
+  end
+
+  class TagDescriptionVersion < ActiveRecord::Base
+    self.table_name = 'tag_description_versions'
+  end
+
+  def up
+    WikiPage.find_each do |page|
+      tag_name = TagName.find_by(id: page.tag_name_id, language_code: 'ja')
+      next unless tag_name&.tag_id
+
+      revisions = WikiRevision.where(wiki_page_id: page.id).order(:id).to_a
+
+      revisions.each_with_index do |revision, index|
+        version_no = index + 1
+
+        tag_id = tag_name[:tag_id]
+
+        unless tag_id
+          raise (
+              'tag_id is nil: ' +
+              "wiki_page_id=#{ page.id }, " +
+              "tag_name_id=#{ tag_name.id }, " +
+              "tag_name=#{ tag_name.attributes.inspect}")
+        end
+
+        revision_id = revision.id
+
+        say (
+            "wiki_page_id=#{ page.id }, " +
+            "tag_name_id=#{ tag_name.id }, " +
+            "tag_id=#{ tag_id }, " +
+            "revision_id=#{ revision_id }")
+
+        version = TagDescriptionVersion.new(
+            id: revision_id,
+            tag_id:,
+            language_code: 'ja',
+            version_no:,
+            event_type: version_no == 1 ? 'create' : 'update',
+            body: revision_body(revision_id),
+            source_language_code: nil,
+            source_version_no: nil,
+            created_by_user_id: revision.created_user_id,
+            created_at: revision.created_at)
+
+        say version.attributes.inspect
+
+        version.save!
+      end
+
+      next if page.discarded_at.present?
+      next if revisions.empty?
+
+      TagDescription.create!(
+          id: page.id,
+          tag_id: tag_name.tag_id,
+          language_code: 'ja',
+          version_no: revisions.length,
+          body: page.body,
+          source_language_code: nil,
+          source_version_no: nil,
+          created_by_user_id: page.created_user_id,
+          updated_by_user_id: page.updated_user_id,
+          created_at: page.created_at,
+          updated_at: page.updated_at)
+    end
+  end
+
+  def down
+    raise ActiveRecord::IrreversibleMigration, '戻せません．'
+  end
+
+  private
+
+  def revision_body revision_id
+    WikiRevisionLine
+        .joins('INNER JOIN wiki_lines ' +
+               'ON wiki_lines.id = wiki_revision_lines.wiki_line_id')
+        .where(wiki_revision_id: revision_id)
+        .order(:position)
+        .pluck('wiki_lines.body')
+        .join("\n")
+  end
+end
diff --git a/backend/db/schema.rb b/backend/db/schema.rb
index eee4568..914edcb 100644
--- a/backend/db/schema.rb
+++ b/backend/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[8.0].define(version: 2026_09_22_040000) do
+ActiveRecord::Schema[8.0].define(version: 2026_10_03_010000) do
   create_table "active_storage_attachments", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.string "name", null: false
     t.string "record_type", null: false
@@ -440,6 +440,49 @@ ActiveRecord::Schema[8.0].define(version: 2026_09_22_040000) do
     t.index ["user_id"], name: "index_settings_on_user_id", unique: true
   end
 
+  create_table "tag_description_versions", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
+    t.bigint "tag_id", null: false
+    t.string "language_code", limit: 16, null: false
+    t.integer "version_no", null: false
+    t.string "event_type", null: false
+    t.text "body", null: false
+    t.string "source_language_code", limit: 16
+    t.integer "source_version_no"
+    t.bigint "created_by_user_id"
+    t.datetime "created_at", null: false
+    t.index ["created_by_user_id"], name: "index_tag_description_versions_on_created_by_user_id"
+    t.index ["tag_id", "language_code", "version_no"], name: "idx_on_tag_id_language_code_version_no_ced77e57e6", unique: true
+    t.index ["tag_id", "source_language_code", "source_version_no"], name: "fk_rails_4f13094dbc"
+    t.index ["tag_id"], name: "index_tag_description_versions_on_tag_id"
+    t.check_constraint "((`source_language_code` is null) and (`source_version_no` is null)) or ((`source_language_code` is not null) and (`source_version_no` is not null))", name: "chk_tag_description_versions_source_pair"
+    t.check_constraint "(`source_language_code` is null) or (`source_language_code` <> `language_code`)", name: "chk_tag_description_versions_source_language_code_different"
+    t.check_constraint "`event_type` in (_utf8mb4'create',_utf8mb4'update',_utf8mb4'discard',_utf8mb4'restore')", name: "tag_description_versions_event_type_valid"
+    t.check_constraint "`version_no` > 0", name: "chk_tag_description_versions_version_no_positive"
+  end
+
+  create_table "tag_descriptions", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
+    t.bigint "tag_id", null: false
+    t.string "language_code", limit: 16, null: false
+    t.integer "version_no", null: false
+    t.text "body", null: false
+    t.string "source_language_code", limit: 16
+    t.integer "source_version_no"
+    t.bigint "created_by_user_id"
+    t.bigint "updated_by_user_id"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["created_by_user_id"], name: "index_tag_descriptions_on_created_by_user_id"
+    t.index ["language_code"], name: "index_tag_descriptions_on_language_code"
+    t.index ["source_language_code", "source_version_no"], name: "idx_on_source_language_code_source_version_no_00117fe02a"
+    t.index ["tag_id", "language_code"], name: "index_tag_descriptions_on_tag_id_and_language_code", unique: true
+    t.index ["tag_id", "source_language_code", "source_version_no"], name: "fk_rails_d1be0a7696"
+    t.index ["tag_id"], name: "index_tag_descriptions_on_tag_id"
+    t.index ["updated_by_user_id"], name: "index_tag_descriptions_on_updated_by_user_id"
+    t.check_constraint "((`source_language_code` is null) and (`source_version_no` is null)) or ((`source_language_code` is not null) and (`source_version_no` is not null))", name: "chk_tag_descriptions_source_pair"
+    t.check_constraint "(`source_language_code` is null) or (`source_language_code` <> `language_code`)", name: "chk_tag_descriptions_source_language_code_different"
+    t.check_constraint "`version_no` > 0", name: "chk_tag_descriptions_version_no_positive"
+  end
+
   create_table "tag_implications", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.bigint "tag_id", null: false
     t.bigint "parent_tag_id", null: false
@@ -656,19 +699,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_09_22_040000) do
     t.index ["banned_at"], name: "index_users_on_banned_at"
   end
 
-  create_table "wiki_assets", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
-    t.bigint "wiki_page_id", null: false
-    t.integer "no", null: false
-    t.string "alt_text"
-    t.binary "sha256", limit: 32, null: false
-    t.bigint "created_by_user_id", null: false
-    t.datetime "created_at", null: false
-    t.datetime "updated_at", null: false
-    t.index ["created_by_user_id"], name: "index_wiki_assets_on_created_by_user_id"
-    t.index ["wiki_page_id", "no"], name: "index_wiki_assets_on_wiki_page_id_and_no", unique: true
-    t.index ["wiki_page_id", "sha256"], name: "index_wiki_assets_on_wiki_page_id_and_sha256", unique: true
-  end
-
   create_table "wiki_lines", charset: "utf8mb4", collation: "utf8mb4_0900_ai_ci", force: :cascade do |t|
     t.string "sha256", limit: 64, null: false
     t.text "body", null: false
@@ -685,7 +715,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_09_22_040000) do
     t.datetime "created_at", null: false
     t.datetime "updated_at", null: false
     t.datetime "discarded_at"
-    t.integer "next_asset_no", default: 1, null: false
     t.integer "version_no", null: false
     t.index ["created_user_id"], name: "index_wiki_pages_on_created_user_id"
     t.index ["discarded_at"], name: "index_wiki_pages_on_discarded_at"
@@ -788,6 +817,12 @@ ActiveRecord::Schema[8.0].define(version: 2026_09_22_040000) do
   add_foreign_key "post_versions", "users", column: "created_by_user_id"
   add_foreign_key "posts", "users", column: "uploaded_user_id"
   add_foreign_key "settings", "users"
+  add_foreign_key "tag_description_versions", "tag_description_versions", column: ["tag_id", "source_language_code", "source_version_no"], primary_key: ["tag_id", "language_code", "version_no"]
+  add_foreign_key "tag_descriptions", "languages", column: "language_code", primary_key: "code"
+  add_foreign_key "tag_descriptions", "tag_description_versions", column: ["tag_id", "source_language_code", "source_version_no"], primary_key: ["tag_id", "language_code", "version_no"]
+  add_foreign_key "tag_descriptions", "tags"
+  add_foreign_key "tag_descriptions", "users", column: "created_by_user_id"
+  add_foreign_key "tag_descriptions", "users", column: "updated_by_user_id"
   add_foreign_key "tag_implications", "tags"
   add_foreign_key "tag_implications", "tags", column: "parent_tag_id"
   add_foreign_key "tag_names", "languages", column: "language_code", primary_key: "code"
@@ -822,8 +857,6 @@ ActiveRecord::Schema[8.0].define(version: 2026_09_22_040000) do
   add_foreign_key "user_post_views", "posts"
   add_foreign_key "user_post_views", "users"
   add_foreign_key "user_theme_slots", "users"
-  add_foreign_key "wiki_assets", "users", column: "created_by_user_id"
-  add_foreign_key "wiki_assets", "wiki_pages"
   add_foreign_key "wiki_pages", "tag_names"
   add_foreign_key "wiki_pages", "users", column: "created_user_id"
   add_foreign_key "wiki_pages", "users", column: "updated_user_id"