#321

backend/app/controllers/tag_versions_controller.rb

@@ -0,0 +1,87 @@
+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_tags =
+          TagRepr.many(
+              Tag
+              .includes(:tag_name, :materials, { tag_name: :wiki_page })
+              .where(id: split_parent_tag_ids(row.parent_tag_ids))
+              .to_a)
+      prev_parent_tags =
+          TagRepr.many(
+              Tag
+              .includes(:tag_name, :materials, { tag_name: :wiki_page })
+              .where(id: split_parent_tag_ids(row.attributes['prev_parent_tag_ids']))
+              .to_a)
+
+      { 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: build_version_values(cur_parent_tags, prev_parent_tags, key: :tag),
+        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/config/routes.rb

@@ -10,6 +10,7 @@ Rails.application.routes.draw do
     collection do
       get :autocomplete
       get :'with-depth', action: :with_depth
+      get :versions, to: 'tag_versions#index'
 
       scope :name do
         get ':name/deerjikists', action: :deerjikists_by_name

frontend/src/App.tsx

@@ -27,6 +27,7 @@ import PostSearchPage from '@/pages/posts/PostSearchPage'
 import ServiceUnavailable from '@/pages/ServiceUnavailable'
 import SettingPage from '@/pages/users/SettingPage'
 import TagDetailPage from '@/pages/tags/TagDetailPage'
+import TagHistoryPage from '@/pages/tags/TagHistoryPage'
 import TagListPage from '@/pages/tags/TagListPage'
 import TheatreDetailPage from '@/pages/theatres/TheatreDetailPage'
 import WikiDetailPage from '@/pages/wiki/WikiDetailPage'
@@ -58,6 +59,7 @@ const RouteTransitionWrapper = ({ user, setUser }: {
 	  <Route path="/tags" element={<TagListPage/>}/>
 	  <Route path="/tags/:id" element={<TagDetailPage/>}/>
 	  <Route path="/tags/nico" element={<NicoTagListPage user={user}/>}/>
+	  <Route path="/tags/changes" element={<TagHistoryPage/>}/>
 	  <Route path="/theatres/:id" element={<TheatreDetailPage/>}/>
 	  <Route path="/materials" element={<MaterialBasePage/>}>
 	    <Route index element={<MaterialListPage/>}/>

frontend/src/components/TopNav.tsx

@@ -41,6 +41,7 @@ export const menuOutline = ({ tag, wikiId, user, pathName }: {
       { name: 'タグ', to: '/tags', subMenu: [
 	  { name: 'マスタ', to: '/tags' },
 	  { name: 'ニコニコ連携', to: '/tags/nico' },
+	  { name: '履歴', to: '/tags/changes' },
 	  { name: 'ヘルプ', to: '/wiki/ヘルプ:タグ' },
 	  { component: <Separator/>, visible: tagFlg },
 	  { name: `広場 (${ postCount || 0 })`,

frontend/src/lib/prefetchers.ts

@@ -3,7 +3,7 @@ import { match } from 'path-to-regexp'
 
 import { fetchPost, fetchPosts, fetchPostChanges } from '@/lib/posts'
 import { postsKeys, tagsKeys, wikiKeys } from '@/lib/queryKeys'
-import { fetchTagByName, fetchTag, fetchTags } from '@/lib/tags'
+import { fetchTagByName, fetchTag, fetchTagChanges, fetchTags } from '@/lib/tags'
 import { fetchWikiPage,
 	 fetchWikiPageByTitle,
 	 fetchWikiPages } from '@/lib/wiki'
@@ -183,6 +183,17 @@ const prefetchTagShow: Prefetcher = async (qc, url) => {
 }
 
 
+const prefetchTagChanges: Prefetcher = async (qc, url) => {
+  const id = url.searchParams.get ('id')
+  const page = Number (url.searchParams.get ('page') || 1)
+  const limit = Number (url.searchParams.get ('limit') || 20)
+
+  await qc.prefetchQuery ({
+      queryKey: tagsKeys.changes ({ ...(id && { id }), page, limit }),
+      queryFn: () => fetchTagChanges ({ ...(id && { id }), page, limit }) })
+}
+
+
 export const routePrefetchers: { test: (u: URL) => boolean; run: Prefetcher }[] = [
     { test: u => ['/', '/posts', '/posts/search'].includes (u.pathname),
       run: prefetchPostsIndex },
@@ -195,8 +206,10 @@ export const routePrefetchers: { test: (u: URL) => boolean; run: Prefetcher }[]
 		  && Boolean (mWiki (u.pathname))),
       run: prefetchWikiPageShow },
     { test: u => u.pathname === '/tags', run: prefetchTagsIndex },
-    { test: u => u.pathname !== '/tags/nico' && Boolean (mTag (u.pathname)),
-      run: prefetchTagShow }]
+    { test: u => (!(['/tags/nico', '/tags/changes'].includes (u.pathname))
+		  && Boolean (mTag (u.pathname))),
+      run: prefetchTagShow },
+    { test: u => u.pathname === '/tags/changes', run: prefetchTagChanges }]
 
 
 export const prefetchForURL = async (qc: QueryClient, urlLike: string): Promise<void> => {

frontend/src/lib/queryKeys.ts

@@ -9,9 +9,11 @@ export const postsKeys = {
 		  ['posts', 'changes', p] as const }
 
 export const tagsKeys = {
-    root:   ['tags'] as const,
-    index:  (p: FetchTagsParams) => ['tags', 'index', p] as const,
-    show:   (name: string) => ['tags', name] as const }
+    root:     ['tags'] as const,
+    index:    (p: FetchTagsParams) => ['tags', 'index', p] as const,
+    show:     (name: string) => ['tags', name] as const,
+    changes:  (p: { id?: string; page: number; limit: number }) =>
+		  ['tags', 'changes', p] as const }
 
 export const wikiKeys = {
     root:   ['wiki'] as const,

frontend/src/lib/tags.ts

@@ -1,6 +1,6 @@
 import { apiGet } from '@/lib/api'
 
-import type { FetchTagsParams, Tag } from '@/types'
+import type { FetchTagsParams, Tag, TagVersion } from '@/types'
 
 
 export const fetchTags = async (
@@ -45,3 +45,14 @@ export const fetchTagByName = async (name: string): Promise<Tag | null> => {
     return null
   }
 }
+
+
+export const fetchTagChanges = async (
+    { id, page, limit }: {
+	id?:    string
+	page:   number
+	limit:  number },
+): Promise<{
+    versions: TagVersion[]
+    count:    number }> =>
+	await apiGet ('/tags/versions', { params: { ...(id && { id }), page, limit } })

frontend/src/pages/tags/TagHistoryPage.tsx

@@ -0,0 +1,212 @@
+import { useQuery, useQueryClient } from '@tanstack/react-query'
+import { useEffect } from 'react'
+import { Helmet } from 'react-helmet-async'
+import { useLocation } from 'react-router-dom'
+
+import PrefetchLink from '@/components/PrefetchLink'
+import PageTitle from '@/components/common/PageTitle'
+import Pagination from '@/components/common/Pagination'
+import MainArea from '@/components/layout/MainArea'
+import { toast } from '@/components/ui/use-toast'
+import { SITE_TITLE } from '@/config'
+import { CATEGORY_NAMES } from '@/consts'
+import { apiPut } from '@/lib/api'
+import { postsKeys, tagsKeys } from '@/lib/queryKeys'
+import { fetchTagChanges } from '@/lib/tags'
+import { cn, dateString } from '@/lib/utils'
+
+import type { FC } from 'react'
+
+
+const renderDiff = (diff: { current: string | null; prev: string | null }) => (
+    <>
+      {(diff.prev && diff.prev !== diff.current) && (
+	  <>
+	    <del className="text-red-600 dark:text-red-400">
+	      {diff.prev}
+	    </del>
+	    {diff.current && <br/>}
+	  </>)}
+      {diff.current}
+    </>)
+
+
+export default (() => {
+  const location = useLocation ()
+  const query = new URLSearchParams (location.search)
+  const id = query.get ('id')
+  const page = Number (query.get ('page') ?? 1)
+  const limit = Number (query.get ('limit') ?? 20)
+
+  const { data, isLoading: loading } = useQuery ({
+      queryKey: tagsKeys.changes ({ ...(id && { id }), page, limit }),
+      queryFn:  () => fetchTagChanges ({ ...(id && { id }), page, limit }) })
+  const changes = data?.versions ?? []
+  const totalPages = data ? Math.ceil (data.count / limit) : 0
+
+  const qc = useQueryClient ()
+
+  useEffect (() => {
+    document.querySelector ('table')?.scrollIntoView ({ behavior: 'smooth' })
+  }, [location.search])
+
+  return (
+      <MainArea>
+	<Helmet>
+	  <title>{`タグ定義変更履歴 | ${ SITE_TITLE }`}</title>
+	</Helmet>
+
+	<PageTitle>
+	  タグ定義変更履歴
+	  {id && <>: タグ {<PrefetchLink to={`/tags/${ id }`}>#{id}</PrefetchLink>}</>}
+	</PageTitle>
+
+	{loading ? 'Loading...' : (
+	    <>
+	      <div className="overflow-x-auto">
+		<table className="w-full min-w-[1200px] table-fixed border-collapse">
+		  <colgroup>
+		    {/* 版 */}
+		    <col className="w-40"/>
+		    {/* 名称 */}
+		    <col className="w-96"/>
+		    {/* カテゴリ */}
+		    <col className="w-96"/>
+		    {/* 別名 */}
+		    <col className="w-[48rem]"/>
+		    {/* 上位タグ */}
+		    <col className="w-96"/>
+		    {/* 更新日時 */}
+		    <col className="w-64"/>
+		    {/* (差戻ボタン) */}
+		    <col className="w-20"/>
+		  </colgroup>
+
+		  <thead className="border-b-2 border-black dark:border-white">
+		    <tr>
+		      <th className="p-2 text-left">版</th>
+		      <th className="p-2 text-left">名称</th>
+		      <th className="p-2 text-left">カテゴリ</th>
+		      <th className="p-2 text-left">別名</th>
+		      <th className="p-2 text-left">上位タグ</th>
+		      <th className="p-2 text-left">更新日時</th>
+		      <th className="p-2"/>
+		    </tr>
+		  </thead>
+
+		  <tbody>
+		    {changes.map (change => (
+			<tr key={`${ change.tagId }.${ change.versionNo }`}
+			    className={cn ('even:bg-gray-100 dark:even:bg-gray-700')}>
+			  <td className="p-2">{change.tagId}.{change.versionNo}</td>
+			  <td className="p-2 break-all">{renderDiff (change.name)}</td>
+			  <td className="p-2 break-all">
+			    {renderDiff ({
+				current: CATEGORY_NAMES[change.category.current],
+				prev: (change.category.prev
+				       && CATEGORY_NAMES[change.category.prev]) })}
+			  </td>
+			  <td className="p-2">
+			    {change.aliases.map ((tag, i) => (
+				tag.type === 'added'
+				? (
+				    <ins
+					key={i}
+					className="mr-2 text-green-600 dark:text-green-400">
+				      {tag.name}
+				    </ins>)
+				: (
+				    tag.type === 'removed'
+				    ? (
+					<del
+					    key={i}
+					    className="mr-2 text-red-600 dark:text-red-400">
+					  {tag.name}
+					</del>)
+				    : (
+					<span key={i} className="mr-2">
+					  {tag.name}
+					</span>))))}
+			  </td>
+			  <td className="p-2">
+			    {change.parentTags.map ((tag, i) => (
+				tag.type === 'added'
+				? (
+				    <ins
+					key={i}
+					className="mr-2 text-green-600 dark:text-green-400">
+				      {tag.tag.name}
+				    </ins>)
+				: (
+				    tag.type === 'removed'
+				    ? (
+					<del
+					    key={i}
+					    className="mr-2 text-red-600 dark:text-red-400">
+					  {tag.tag.name}
+					</del>)
+				    : (
+					<span key={i} className="mr-2">
+					  {tag.tag.name}
+					</span>))))}
+			  </td>
+			  <td className="p-2">
+			    {change.createdByUser
+			     ? (
+				<PrefetchLink to={`/users/${ change.createdByUser.id }`}>
+				  {change.createdByUser.name
+				   || `名もなきニジラー（#${ change.createdByUser.id }）`}
+				</PrefetchLink>)
+			     : 'bot 操作'}
+			    <br/>
+			    {dateString (change.createdAt)}
+			  </td>
+			  <td className="p-2">
+			    <a
+				href="#"
+				onClick={async e => {
+				  e.preventDefault ()
+
+				  if (!(confirm (
+				      `タグ『${ change.name.current }』を版 ${
+				      change.versionNo } に差戻します．\nよろしいですか?`)))
+				    return
+
+				  try
+				  {
+				    await apiPut (
+					`/tags/${ change.tagId }`,
+					{ name: change.name.current,
+					  category: change.category.current,
+					  aliases:
+					      change.aliases
+					      .filter (t => t.type !== 'removed')
+					      .map (t => t.name)
+					      .join (' '),
+					  parent_tags:
+					      change.parentTags
+					      .filter (t => t.type !== 'removed')
+					      .map (t => t.tag.name)
+					      .join (' ') })
+
+				    qc.invalidateQueries ({ queryKey: postsKeys.root })
+				    qc.invalidateQueries ({ queryKey: tagsKeys.root })
+				    toast ({ description: '差戻しました．' })
+				  }
+				  catch
+				  {
+				    toast ({ description: '差戻に失敗……' })
+				  }
+				}}>
+			      復元
+			    </a>
+			  </td>
+			</tr>))}
+		  </tbody>
+		</table>
+	      </div>
+
+	      <Pagination page={page} totalPages={totalPages}/>
+	    </>)}
+      </MainArea>)
+}) satisfies FC

frontend/src/types.ts

@@ -175,6 +175,17 @@ export type Tag = {
     children?:      Tag[]
     matchedAlias?:  string | null }
 
+export type TagVersion = {
+    tagId:                  number
+    versionNo:              number
+    eventType:              'create' | 'update' | 'discard' | 'restore'
+    name:                   { current: string; prev: string | null }
+    category:               { current: Category; prev: Category | null }
+    aliases:                { name: string; type: 'context' | 'added' | 'removed' }[]
+    parentTags:             { tag: Tag; type: 'context' | 'added' | 'removed' }[]
+    createdAt:              string
+    createdByUser:          { id: number; name: string | null } | null }
+
 export type Theatre = {
     id:             number
     name:           string | null