#428

frontend/src/components/PostEmbed.tsx

@@ -3,9 +3,10 @@ import YoutubeEmbed from 'react-youtube'
 
 import NicoViewer from '@/components/NicoViewer'
 import TwitterEmbed from '@/components/TwitterEmbed'
-import { useDialogue } from '@/components/dialogues/DialogueProvider'
+import useDialogue from '@/lib/dialogues/useDialogue'
 import { Button } from '@/components/ui/button'
 import { useClientBehaviourSettings } from '@/lib/useClientBehaviourSettings'
+import { useUITranslation } from '@/lib/useUITranslation'
 
 import type { FC, RefObject } from 'react'
 
@@ -36,6 +37,7 @@ const PostEmbed: FC<Props> = (
       onError },
 ) => {
   const dialogue = useDialogue ()
+  const { label } = useUITranslation ('posts')
   const behaviourSettings = useClientBehaviourSettings ()
   const embedAutoLoadMode = behaviourSettings.embedAutoLoad ?? 'auto'
   const [manualLoadRequested, setManualLoadRequested] = useState (false)
@@ -135,7 +137,7 @@ const PostEmbed: FC<Props> = (
 
   const externalLink = (
       <a href={post.url} target="_blank" rel="noreferrer">
-	外部ページを開く
+	{label ('embed.openExternal')}
       </a>)
 
   const manualLoadControl = (
@@ -144,7 +146,7 @@ const PostEmbed: FC<Props> = (
 	    type="button"
 	    variant="outline"
 	    onClick={() => setManualLoadRequested (true)}>
-	  埋め込みを読込
+	  {label ('embed.load')}
 	</Button>
 	{externalLink}
       </div>)
@@ -239,15 +241,15 @@ const PostEmbed: FC<Props> = (
 		e.preventDefault ()
 
 		setFramed (await dialogue.confirm ({
-		    title: '未確認の外部ページを表示します。',
+		    title: label ('embed.confirmTitle'),
 		    description: (
 			<div>
-			  <p>悪意のあるスクリプトが実行される可能性があります。</p>
+			  <p>{label ('embed.risk')}</p>
-			  <p>表示しますか?</p>
+			  <p>{label ('embed.question')}</p>
 			</div>),
-		    confirmText: '表示' }))
+		    confirmText: label ('shared:actions.show') }))
 	      }}>
-		外部ページを表示
+		{label ('embed.showExternal')}
 	      </a>)}
 	    </div>)}
       </>)

frontend/src/components/PostFormTagsArea.tsx

@@ -9,7 +9,7 @@ import FormField from '@/components/common/FormField'
 import TextArea from '@/components/common/TextArea'
 import { apiGet } from '@/lib/api'
 
-import type { ComponentPropsWithoutRef, FC, SyntheticEvent } from 'react'
+import type { ComponentPropsWithoutRef, FC, ReactNode, SyntheticEvent } from 'react'
 
 import type { Tag } from '@/types'
 
@@ -36,7 +36,7 @@ const replaceToken = (value: string, start: number, end: number, text: string) =
 type Props = Omit<ComponentPropsWithoutRef<'textarea'>, 'value' | 'onChange' | 'onBlur'> & {
     tags:     string
     setTags:  (tags: string) => void
-    errors?:  string[] }
+    errors?:  ReactNode[] }
 
 
 const PostFormTagsArea: FC<Props> = ({ tags, setTags, errors, ...rest }) => {

frontend/src/components/PostOriginalCreatedTimeField.tsx

@@ -3,7 +3,7 @@ import FormField from '@/components/common/FormField'
 import { Button } from '@/components/ui/button'
 import { useUITranslation } from '@/lib/useUITranslation'
 
-import type { FC } from 'react'
+import type { FC, ReactNode } from 'react'
 
 type Props = {
     disabled?:                boolean
@@ -11,7 +11,7 @@ type Props = {
     setOriginalCreatedFrom:   (x: string | null) => void
     originalCreatedBefore:    string | null
     setOriginalCreatedBefore: (x: string | null) => void
-    errors?:                  string[] }
+    errors?:                  ReactNode[] }
 
 
 const PostOriginalCreatedTimeField: FC<Props> = (

frontend/src/components/RouteBlockerOverlay.tsx

@@ -1,6 +1,10 @@
 import { useEffect } from 'react'
+import { useTranslation } from 'react-i18next'
 import { create } from 'zustand'
 
+import LocalisedText from '@/components/LocalisedText'
+import { translateUIMessage } from '@/lib/i18n'
+
 import type { FC } from 'react'
 
 type OverlayStore = {
@@ -14,6 +18,9 @@ export const useOverlayStore = create<OverlayStore> (set => ({
 
 
 const RouteBlockerOverlay: FC = () => {
+  const { i18n } = useTranslation ('common')
+  const loading = translateUIMessage ('loading', 'common', i18n.language)
+  const loadingLabel = translateUIMessage ('loadingLabel', 'common', i18n.language)
   const active = useOverlayStore (s => s.active)
 
   useEffect (() => {
@@ -35,11 +42,12 @@ const RouteBlockerOverlay: FC = () => {
   return (
       <div
 	  role="progressbar"
-	  aria-label="Loading"
+	  aria-label={loadingLabel.text}
+	  lang={loadingLabel.language}
 	  className="fixed inset-0 z-[9999] bg-black/50 backdrop-blur-sm pointer-events-auto">
 	<div className="absolute inset-0 flex items-center justify-center">
 	  <div className="rounded-2xl bg-black/60 text-white px-6 py-3 text-sm">
-	    Loading...
+	    <LocalisedText language={loading.language}>{loading.text}</LocalisedText>
 	  </div>
 	</div>
       </div>)

frontend/src/components/TagDetailSidebar.tsx

@@ -26,7 +26,9 @@ import { apiDelete, apiGet, apiPatch, apiPost } from '@/lib/api'
 import { clientAnimationTransition } from '@/lib/clientAnimation'
 import { postsKeys, tagsKeys } from '@/lib/queryKeys'
 import { useClientBehaviourSettings } from '@/lib/useClientBehaviourSettings'
-import { dateString, originalCreatedAtString } from '@/lib/utils'
+import { localisedDateString, originalCreatedAtString } from '@/lib/utils'
+import LocalisedText from '@/components/LocalisedText'
+import { useUITranslation } from '@/lib/useUITranslation'
 
 import type { LocaleCode } from '@/lib/locales'
 import type { CollisionDetection, DragEndEvent } from '@dnd-kit/core'
@@ -232,6 +234,7 @@ type ActiveTagDrag = {
 
 const TagDetailSidebar: FC<Props> = ({ className, post, sp }) => {
   const locale = useLocale ()
+  const { label } = useUITranslation ('tags')
   sp = Boolean (sp)
 
   const qc = useQueryClient ()
@@ -325,8 +328,9 @@ const TagDetailSidebar: FC<Props> = ({ className, post, sp }) => {
 
 	  await reloadTags ()
 	  toast ({
-	      title: '上位タグ対応追加',
+	      title: label ('relations.added'),
-	      description: `《${ child?.name }》を《${ parent?.name }》の子タグに設定しました．` })
+	      description: label ('relations.addedDescription', {
+		  child: child.name, parent: parent.name }) })
 
 	  break
 	}
@@ -347,11 +351,12 @@ const TagDetailSidebar: FC<Props> = ({ className, post, sp }) => {
 
 	  await reloadTags ()
 	  toast ({
-	      title: '上位タグ対応解除',
+	      title: label ('relations.removed'),
 	      description: (
 		  fromParent
-		  ? `《${ child.name }》を《${ fromParent.name }》の子タグから外しました．`
+		  ? label ('relations.removedDescription', {
-		  : `《${ child.name }》のカテゴリを変更しました．`) })
+		      child: child.name, parent: fromParent.name })
+		  : label ('relations.categoryChanged', { name: child.name })) })
 
 	  break
 	}
@@ -359,7 +364,8 @@ const TagDetailSidebar: FC<Props> = ({ className, post, sp }) => {
     }
     catch
     {
-      toast ({ title: '上位タグ対応失敗', description: '独裁者である必要があります．' })
+      toast ({ title: label ('relations.failed'),
+	  description: label ('relations.permissionRequired') })
     }
     finally
     {
@@ -473,21 +479,26 @@ const TagDetailSidebar: FC<Props> = ({ className, post, sp }) => {
 		      ? undefined
 		      : `post-info-${ sp }`}
 		  transition={{ layout: layoutTransition }}>
-		<SectionTitle>情報</SectionTitle>
+		<SectionTitle>{label ('shared:labels.information')}</SectionTitle>
 		<ul>
-		  <li>Id.: {post.id}</li>
+		  <li>{label ('shared:idPrefix')}{post.id}</li>
 		  <li>
-		    <>耕作者: </>
+		    {label ('shared:labels.uploadedBy')}
 		    {post.uploadedUser
 		     ? (
 			<PrefetchLink to={`/users/${ post.uploadedUser.id }`}>
-			  {post.uploadedUser.name || '名もなきニジラー'}
+			  {post.uploadedUser.name || label ('shared:labels.anonymous')}
 			</PrefetchLink>)
-		     : 'bot操作'}
+		     : label ('shared:labels.bot')}
 		  </li>
-		  <li>耕作日時: {dateString (post.createdAt)}</li>
 		  <li>
-		    <>リンク: </>
+		    {label ('shared:labels.uploadedAt')}
+		    <LocalisedText language={locale}>
+		      {localisedDateString (post.createdAt, locale)}
+		    </LocalisedText>
+		  </li>
+		  <li>
+		    {label ('shared:labels.link')}
 		    <a
 			className="break-all"
 			href={post.url}
@@ -497,13 +508,15 @@ const TagDetailSidebar: FC<Props> = ({ className, post, sp }) => {
 		    </a>
 		  </li>
 		  <li>
-		    <>オリジナルの投稿日時: </>
+		    {label ('shared:labels.originalPostedAt')}
+		    <LocalisedText language={locale}>
 		      {originalCreatedAtString (post.originalCreatedFrom,
-					      post.originalCreatedBefore)}
+			  post.originalCreatedBefore, locale)}
+		    </LocalisedText>
 		  </li>
 		  <li>
 		    <PrefetchLink to={`/posts/changes?id=${ post.id }`}>
-		      履歴
+		      {label ('navigation:history')}
 		    </PrefetchLink>
 		  </li>
 		</ul>

frontend/src/components/TopNav.tsx

@@ -126,7 +126,7 @@ export const menuOutline = (
 
 
 const TopNav: FC<Props> = ({ user, locales }) => {
-  const { label } = useUITranslation ('shared')
+  const { message, label } = useUITranslation ('shared')
   const locale = useLocale ()
   const localeName = locales.find (entry => entry.code === locale)?.name
   const navigate = useLocaleNavigate ()
@@ -177,6 +177,7 @@ const TopNav: FC<Props> = ({ user, locales }) => {
       width:    0,
       visible:  false })
   const [menuOpen, setMenuOpen] = useState (false)
+  const menuToggleLabel = message (menuOpen ? 'dialogue.close' : 'navigation:menuToggle')
   const [desktop, setDesktop] = useState (false)
   const [density, setDensity] = useState<NavDensity> ('auto')
   const [moreVsbl, setMoreVsbl] = useState (false)
@@ -474,10 +475,12 @@ const TopNav: FC<Props> = ({ user, locales }) => {
 		type="button"
 		className="top-nav-mobile-toggle shrink-0 whitespace-nowrap
 			   border-0 bg-transparent pr-4"
+		aria-label={menuToggleLabel.text}
+		lang={menuToggleLabel.language}
 		onClick={() => {
 		  setMenuOpen (!(menuOpen))
 		}}>
-	      {menuOpen ? '×' : 'Menu'}
+	      {menuOpen ? '×' : label ('navigation:menuToggle')}
 	    </button>
 	  </div>
 	</nav>

frontend/src/components/common/FieldWarning.tsx

@@ -1,7 +1,7 @@
-import type { FC } from 'react'
+import type { FC, ReactNode } from 'react'
 
 type Props = { id?:        string
-	       messages?:  string[] }
+	       messages?:  ReactNode[] }
 
 
 export const FieldWarning: FC<Props> = ({ id, messages }: Props) => {

frontend/src/components/common/FormField.tsx

@@ -16,7 +16,7 @@ type Props = {
 		   onChange: (event: React.ChangeEvent<HTMLInputElement>) => void }
     className?:  string
     label:      ReactNode
-    messages?:  string[] }
+    messages?:  ReactNode[] }
 
 
 const FormField: FC<Props> = ({ children, checkBox, className, label, messages }: Props) => {

frontend/src/components/dialogues/DialogueProvider.tsx

@@ -8,6 +8,7 @@ import { Dialog,
 	 DialogHeader,
 	 DialogTitle } from '@/components/ui/dialog'
 import { DialogueContext } from '@/lib/dialogues/useDialogue'
+import { useUITranslation } from '@/lib/useUITranslation'
 
 import type { FC, ReactNode } from 'react'
 import type { AlertOptions,
@@ -42,6 +43,7 @@ type Props = { children: ReactNode }
 
 
 const DialogueProvider: FC<Props> = ({ children }) => {
+  const { label } = useUITranslation ('shared')
   const [queue, setQueue] = useState<DialogueRequest[]> ([])
   const [pendingIds, setPendingIds] = useState<number[]> ([])
   const [formActions, setFormActions] = useState<Record<number, DialogueFormAction[]>> ({ })
@@ -220,9 +222,9 @@ const DialogueProvider: FC<Props> = ({ children }) => {
 			   className="shrink-0 flex-col gap-2 pt-4
 				      md:flex-row md:justify-between md:gap-0 md:space-x-0">
 			 <div className="flex w-full flex-col gap-2 md:w-auto md:flex-row">
-			   {startActions.map (action => (
+			   {startActions.map ((action, index) => (
 			       <Button
-				   key={action.label}
+				   key={index}
 				   className="w-full md:w-auto"
 				   variant={action.variant === 'danger'
 				       ? 'destructive'
@@ -242,12 +244,12 @@ const DialogueProvider: FC<Props> = ({ children }) => {
 			       onClick={() => closeRequest (active.id)}
 			       disabled={pendingIds.includes (active.id)
 				   || nestedConfirm?.parentId === active.id}>
-			     {active.options.cancelText ?? '取消'}
+			     {active.options.cancelText ?? label ('actions.cancel')}
 			   </Button>
 
-			   {endActions.map (action => (
+			   {endActions.map ((action, index) => (
 			       <Button
-				   key={action.label}
+				   key={index}
 				   className="w-full md:w-auto"
 				   variant={action.variant === 'danger'
 				       ? 'destructive'
@@ -278,7 +280,7 @@ const DialogueProvider: FC<Props> = ({ children }) => {
 			       <Button
 				   variant="outline"
 				   onClick={() => closeRequest (active.id, false)}>
-				 {active.options.cancelText ?? '取消'}
+				 {active.options.cancelText ?? label ('actions.cancel')}
 			       </Button>
 
 			       <Button
@@ -286,13 +288,13 @@ const DialogueProvider: FC<Props> = ({ children }) => {
 					    ? 'destructive'
 					    : 'default'}
 				   onClick={() => closeRequest (active.id, true)}>
-				 {active.options.confirmText ?? '確定'}
+				 {active.options.confirmText ?? label ('dialogue.confirm')}
 			       </Button>
 			     </>)}
 
 			 {active.kind === 'alert' && (
 			     <Button onClick={() => closeRequest (active.id)}>
-			       {active.options.okText ?? '確定'}
+			       {active.options.okText ?? label ('dialogue.confirm')}
 			     </Button>)}
 
 			 {active.kind === 'choice' && (
@@ -300,7 +302,7 @@ const DialogueProvider: FC<Props> = ({ children }) => {
 			       <Button
 				   variant="outline"
 				   onClick={() => closeRequest (active.id, null)}>
-				 {active.options.cancelText ?? '取消'}
+				 {active.options.cancelText ?? label ('actions.cancel')}
 			       </Button>
 
 			       {active.options.choices.map (choice => (
@@ -340,7 +342,7 @@ const DialogueProvider: FC<Props> = ({ children }) => {
 		  <Button
 		      variant="outline"
 		      onClick={() => closeNestedConfirm (false)}>
-		    {nestedConfirm.options.cancelText ?? '取消'}
+		    {nestedConfirm.options.cancelText ?? label ('actions.cancel')}
 		  </Button>
 
 		  <Button
@@ -348,7 +350,7 @@ const DialogueProvider: FC<Props> = ({ children }) => {
 			  ? 'destructive'
 			  : 'default'}
 		      onClick={() => closeNestedConfirm (true)}>
-		    {nestedConfirm.options.confirmText ?? '確定'}
+		    {nestedConfirm.options.confirmText ?? label ('dialogue.confirm')}
 		  </Button>
 		</DialogFooter>
 	      </DialogContent>

frontend/src/components/layout/SidebarComponent.tsx

@@ -4,6 +4,7 @@ import { Helmet } from 'react-helmet-async'
 import { clientAnimationTransition } from '@/lib/clientAnimation'
 import { useClientBehaviourSettings } from '@/lib/useClientBehaviourSettings'
 import { cn } from '@/lib/utils'
+import { useUITranslation } from '@/lib/useUITranslation'
 
 import type { CSSProperties, FC, MouseEvent, PointerEvent, ReactNode } from 'react'
 import { useCallback, useEffect, useRef, useState } from 'react'
@@ -70,6 +71,7 @@ const SidebarComponent: FC<Props> = ({
     sidebarKey,
     side = 'left',
 }) => {
+  const { message } = useUITranslation ('shared')
   const behaviourSettings = useClientBehaviourSettings ()
   const animationMode = behaviourSettings.animation ?? 'normal'
   const layoutTransition = clientAnimationTransition (
@@ -341,7 +343,8 @@ const SidebarComponent: FC<Props> = ({
 	<div
 	    role="separator"
 	    aria-orientation="vertical"
-	    aria-label="サイドバー幅"
+	    aria-label={message ('sidebarWidth').text}
+	    lang={message ('sidebarWidth').language}
 	    onPointerDown={handlePointerDown}
 	    onPointerMove={handlePointerMove}
 	    onPointerUp={handlePointerEnd}

frontend/src/components/posts/PostCoreDataFields.tsx

@@ -5,7 +5,7 @@ import TranslatedText from '@/components/TranslatedText'
 
 import type { FC, ReactNode } from 'react'
 
-type TextMessages = string[] | undefined
+type TextMessages = ReactNode[] | undefined
 
 type CoreField = {
   value:    string
@@ -43,7 +43,7 @@ type PostCoreDataFieldsProps = {
     rows?:     number }
   parentPostIds: CoreField }
 
-const groupedMessages = (...values: (TextMessages | null | undefined)[]): string[] =>
+const groupedMessages = (...values: (TextMessages | null | undefined)[]): ReactNode[] =>
     [...new Set (values.flatMap (value => value ?? []))]
 
 

frontend/src/components/posts/PostCreationDataFields.tsx

@@ -1,11 +1,12 @@
 import PostCoreDataFields from '@/components/posts/PostCoreDataFields'
 import PostTextField from '@/components/posts/PostTextField'
+import TranslatedText from '@/components/TranslatedText'
 
 import type { FC, ReactNode } from 'react'
 
 import type { PostCoreDataFieldsProps } from '@/components/posts/PostCoreDataFields'
 
-type TextMessages = string[] | undefined
+type TextMessages = ReactNode[] | undefined
 
 type Props = {
   url: {
@@ -29,7 +30,7 @@ const PostCreationDataFields: FC<Props> = (
 ) => (
     <>
       <PostTextField
-          label="URL"
+          label={<TranslatedText namespace="shared" messageKey="url"/>}
           type={url.type}
           value={url.value}
           disabled={url.disabled}

frontend/src/components/posts/PostDurationField.tsx

@@ -1,12 +1,12 @@
 import PostTextField from '@/components/posts/PostTextField'
 import TranslatedText from '@/components/TranslatedText'
 
-import type { FC } from 'react'
+import type { FC, ReactNode } from 'react'
 
 type Props = {
   value:     string
   onChange:  (value: string) => void
-  errors?:   string[]
+  errors?:   ReactNode[]
   disabled?: boolean }
 
 

frontend/src/components/posts/PostTagsField.tsx

@@ -1,13 +1,13 @@
 import PostFormTagsArea from '@/components/PostFormTagsArea'
 import FieldWarning from '@/components/common/FieldWarning'
 
-import type { ComponentPropsWithoutRef, FC } from 'react'
+import type { ComponentPropsWithoutRef, FC, ReactNode } from 'react'
 
 type Props = Omit<ComponentPropsWithoutRef<'textarea'>, 'value' | 'onChange'> & {
   tags:      string
   setTags:   (tags: string) => void
-  warnings?: string[]
+  warnings?: ReactNode[]
-  errors?:   string[] }
+  errors?:   ReactNode[] }
 
 
 const PostTagsField: FC<Props> = (

frontend/src/components/posts/PostTextField.tsx

@@ -8,8 +8,8 @@ type Props = {
   label:        ReactNode
   value:        string
   onChange:     (value: string) => void
-  warnings?:    string[]
+  warnings?:    ReactNode[]
-  errors?:      string[]
+  errors?:      ReactNode[]
   disabled?:    boolean
   type?:        string
   placeholder?: string

frontend/src/components/posts/import/PostImportRowForm.tsx

@@ -7,8 +7,11 @@ import PostDurationField from '@/components/posts/PostDurationField'
 import PostTextField from '@/components/posts/PostTextField'
 import PostImportThumbnailPreview from '@/components/posts/import/PostImportThumbnailPreview'
 import { hasThumbnailBaseValue, hasVideoTag } from '@/lib/postImportRows'
+import { renderPostImportMessage } from '@/components/posts/import/postImportRowStatus'
+import { useLocale } from '@/lib/useLocale'
+import { useUITranslation } from '@/lib/useUITranslation'
 
-import type { FC } from 'react'
+import type { FC, ReactNode } from 'react'
 
 import type { DialogueFormControls } from '@/lib/dialogues/useDialogue'
 import type { PostImportEditableDraft, PostImportRow } from '@/lib/postImportTypes'
@@ -47,9 +50,6 @@ const buildResetDraft = (row: PostImportRow): Draft => ({
     duration: String (row.resetSnapshot.attributes.duration ?? ''),
     thumbnailFile: undefined })
 
-const groupedMessages = (...values: (string[] | undefined)[]): string[] =>
-    [...new Set (values.flatMap (value => value ?? []))]
-
 const sameDraft = (left:  Draft, right: Draft): boolean =>
     left.url === right.url
     && left.title === right.title
@@ -98,6 +98,11 @@ const PostImportRowForm: FC<Props> = (
       controls,
       onSave },
 ) => {
+  const locale = useLocale ()
+  const { label } = useUITranslation ('imports')
+  const groupedMessages = (...values: (string[] | undefined)[]): ReactNode[] =>
+      [...new Set (values.flatMap (value => value ?? []))]
+      .map (value => renderPostImportMessage (value, locale))
   const [draft, setDraft] = useState<Draft> (() => buildDraft (row))
   const [messageRow, setMessageRow] = useState<PostImportRow | null> (null)
   const [saving, setSaving] = useState (false)
@@ -144,9 +149,9 @@ const PostImportRowForm: FC<Props> = (
       return false
 
     const confirmed = await controls.confirm ({
-	title: '変更をリセットしますか?',
+	title: label ('shared:messages.resetChanges'),
-	confirmText: 'リセット',
+	confirmText: label ('shared:actions.reset'),
-	cancelText: '取消',
+	cancelText: label ('shared:actions.cancel'),
 	variant: 'danger' })
     if (!(confirmed))
       return false
@@ -156,7 +161,7 @@ const PostImportRowForm: FC<Props> = (
     setMessageRow (null)
     setCommittedThumbnailBase (resetDraft.thumbnailBase)
     return false
-  }, [controls, resetDisabled, resetDraft])
+  }, [controls, resetDisabled, resetDraft, label])
 
   const save = useCallback (async (): Promise<boolean> => {
     setSaving (true)
@@ -178,16 +183,16 @@ const PostImportRowForm: FC<Props> = (
 
   useEffect (() => {
     controls.setActions ([{
-	label: '変更をリセット',
+	label: label ('review.reset'),
 	placement: 'start',
 	variant: 'danger',
 	disabled: resetDisabled,
 	onSelect: reset },
 	{
-	  label: '編輯内容を保存',
+	  label: label ('review.save'),
 	  disabled: saving,
 	  onSelect: save }])
-  }, [controls, resetDisabled, reset, save, saving])
+  }, [controls, resetDisabled, reset, save, saving, label])
 
   return (
       <>
@@ -210,17 +215,17 @@ const PostImportRowForm: FC<Props> = (
 			value: draft.url,
 			onChange: value => update ('url', value),
 			disabled: saving,
-			warnings: displayRow.fieldWarnings.url,
+			warnings: groupedMessages (displayRow.fieldWarnings.url),
 			errors: groupedMessages (
 			    displayRow.validationErrors.url,
 			    displayRow.importErrors?.url) }}
 		    thumbnailField={
 			<>
 			  <PostTextField
-			      label="サムネール"
+			      label={label ('shared:labels.thumbnail')}
 			      value={draft.thumbnailBase}
 			      disabled={saving}
-			      warnings={currentThumbnailWarnings}
+			      warnings={groupedMessages (currentThumbnailWarnings)}
 			      errors={groupedMessages (
 				  displayRow.validationErrors.thumbnailBase,
 				  displayRow.importErrors?.thumbnailBase)}
@@ -244,7 +249,7 @@ const PostImportRowForm: FC<Props> = (
 			    value: draft.title,
 			    onChange: value => update ('title', value),
 			    disabled: saving,
-			    warnings: displayRow.fieldWarnings.title,
+			    warnings: groupedMessages (displayRow.fieldWarnings.title),
 			    errors: groupedMessages (
 				displayRow.validationErrors.title,
 				displayRow.importErrors?.title) },
@@ -270,7 +275,7 @@ const PostImportRowForm: FC<Props> = (
 			    value: draft.tags,
 			    onChange: value => update ('tags', value),
 			    disabled: saving,
-			    warnings: displayRow.fieldWarnings.tags,
+			    warnings: groupedMessages (displayRow.fieldWarnings.tags),
 			    errors: groupedMessages (
 				displayRow.validationErrors.tags,
 				displayRow.importErrors?.tags),
@@ -293,9 +298,9 @@ const PostImportRowForm: FC<Props> = (
 				    displayRow.validationErrors.videoMs,
 				    displayRow.importErrors?.videoMs)}/>)
 			: null}/>
-		<FieldWarning messages={displayRow.baseWarnings}/>
+		<FieldWarning messages={groupedMessages (displayRow.baseWarnings)}/>
-		<FieldError messages={displayRow.validationErrors.base}/>
+		<FieldError messages={groupedMessages (displayRow.validationErrors.base)}/>
-		<FieldError messages={displayRow.importErrors?.base}/>
+		<FieldError messages={groupedMessages (displayRow.importErrors?.base)}/>
 	      </div>
 	    </div>
 	  </div>

frontend/src/components/posts/import/PostImportRowSummary.tsx

@@ -3,7 +3,11 @@ import PostImportTagLinks from '@/components/posts/import/PostImportTagLinks'
 import { Button } from '@/components/ui/button'
 import PostImportThumbnailPreview from '@/components/posts/import/PostImportThumbnailPreview'
 import PostImportStatusBadge from '@/components/posts/import/PostImportStatusBadge'
-import { displayPostImportStatus } from '@/components/posts/import/postImportRowStatus'
+import { displayPostImportStatus,
+	 renderPostImportMessage } from '@/components/posts/import/postImportRowStatus'
+import LocalisedText from '@/components/LocalisedText'
+import { useLocale } from '@/lib/useLocale'
+import { useUITranslation } from '@/lib/useUITranslation'
 import {
     canEditReviewRow,
     canRetryResultRow,
@@ -14,6 +18,7 @@ import { cn, originalCreatedAtString } from '@/lib/utils'
 import type { FC } from 'react'
 
 import type { PostImportRow } from '@/lib/postImportTypes'
+import type { LocaleCode } from '@/lib/locales'
 
 type Props = {
     row:	      PostImportRow
@@ -33,10 +38,10 @@ const summaryWarning = (row: PostImportRow): string | null =>
     ?? row.baseWarnings?.[0]
     ?? null
 
-const summaryDate = (row: PostImportRow): string =>
+const summaryDate = (row: PostImportRow, locale: LocaleCode): string =>
     originalCreatedAtString (
 	row.attributes.originalCreatedFrom?.toString () ?? null,
-	row.attributes.originalCreatedBefore?.toString () ?? null)
+	row.attributes.originalCreatedBefore?.toString () ?? null, locale)
 
 
 const PostImportRowSummary: FC<Props> = (
@@ -52,6 +57,10 @@ const PostImportRowSummary: FC<Props> = (
       showActions = true,
       showSkipToggle = false },
 ) => {
+  const locale = useLocale ()
+  const { label } = useUITranslation ('imports')
+  const localisedRowMessages = rowMessages?.map (value =>
+      renderPostImportMessage (value, locale))
   const warning = summaryWarning (row)
   const displayStatus = displayPostImportStatus (row)
   const editVisible = onEdit != null
@@ -69,7 +78,7 @@ const PostImportRowSummary: FC<Props> = (
 		checked={skipChecked}
 		onChange={event => onToggleSkip?.(event.target.checked)}
 		disabled={skipDisabled === true}/>
-	    <span>スキップ</span>
+	    <span>{label ('shared:actions.skip')}</span>
 	  </label>)
       : null
 
@@ -96,17 +105,17 @@ const PostImportRowSummary: FC<Props> = (
 	    </div>
 	    <PostImportTagLinks tags={row.displayTags}/>
 	    <div className="text-xs text-neutral-500 dark:text-neutral-400">
-	      {summaryDate (row)}
+	      <LocalisedText language={locale}>{summaryDate (row, locale)}</LocalisedText>
 	    </div>
 	    {showDuration && (
 		<div className="text-xs text-neutral-500 dark:text-neutral-400">
-		  動画時間 {duration}
+		  {label ('review.duration', { duration })}
 		</div>)}
 	    {warning && (
 		<div className="text-xs text-amber-700 dark:text-amber-200">
-		  {warning}
+		  {renderPostImportMessage (warning, locale)}
 		</div>)}
-	    <FieldError messages={rowMessages}/>
+	    <FieldError messages={localisedRowMessages}/>
 	  </div>
 	  <div className="space-y-1">
 	    {displayStatus != null && <PostImportStatusBadge value={displayStatus}/>}
@@ -120,7 +129,7 @@ const PostImportRowSummary: FC<Props> = (
 		      variant="outline"
 		      onClick={onEdit}
 		      disabled={editDisabled === true || !(editAllowed)}>
-		    編輯
+		    {label ('shared:actions.edit')}
 		  </Button>)}
 	      {showActions && retryAllowed && (
 		  <Button
@@ -128,7 +137,7 @@ const PostImportRowSummary: FC<Props> = (
 		      variant="outline"
 		      onClick={onRetry}
 		      disabled={retryDisabled === true}>
-		    再試行
+		    {label ('shared:actions.retry')}
 		  </Button>)}
 	    </div>
 	  </div>
@@ -156,17 +165,17 @@ const PostImportRowSummary: FC<Props> = (
 	      </div>
 	      <PostImportTagLinks tags={row.displayTags}/>
 	      <div className="text-xs text-neutral-500 dark:text-neutral-400">
-		{summaryDate (row)}
+		<LocalisedText language={locale}>{summaryDate (row, locale)}</LocalisedText>
 	      </div>
 	      {showDuration && (
 		  <div className="text-xs text-neutral-500 dark:text-neutral-400">
-		    動画時間 {duration}
+		    {label ('review.duration', { duration })}
 		  </div>)}
 	      {warning && (
 		  <div className="text-xs text-amber-700 dark:text-amber-200">
-		    {warning}
+		    {renderPostImportMessage (warning, locale)}
 		  </div>)}
-	      <FieldError messages={rowMessages}/>
+	      <FieldError messages={localisedRowMessages}/>
 	      {skipControl}
 	    </div>
 	  </div>
@@ -179,7 +188,7 @@ const PostImportRowSummary: FC<Props> = (
 			variant="outline"
 			onClick={onEdit}
 			disabled={editDisabled === true || !(editAllowed)}>
-		      編輯
+		      {label ('shared:actions.edit')}
 		    </Button>)}
 		{retryAllowed && (
 		    <Button
@@ -188,7 +197,7 @@ const PostImportRowSummary: FC<Props> = (
 			variant="outline"
 			onClick={onRetry}
 			disabled={retryDisabled === true}>
-		      再試行
+		      {label ('shared:actions.retry')}
 		    </Button>)}
 	      </div>)}
 	</div>

frontend/src/components/posts/import/postImportRowStatus.ts

@@ -1,3 +1,10 @@
+import { createElement } from 'react'
+
+import LocalisedText from '@/components/LocalisedText'
+import { i18n, translateUIMessage } from '@/lib/i18n'
+
+import type { ReactNode } from 'react'
+
 import type { PostImportRow } from '@/lib/postImportTypes'
 
 export type PostImportDisplayStatus =
@@ -10,6 +17,40 @@ export type PostImportDisplayStatus =
 
 export type PostImportBadgeValue = PostImportDisplayStatus
 
+const IMPORT_MESSAGE_KEYS = [
+    'validation.duplicateUrl', 'validation.processingFailed',
+    'validation.tooMany', 'validation.urlTooLong', 'validation.invalidUrl',
+    'validation.protocol', 'validation.duplicateRow', 'storage.readFailed',
+    'storage.writeFailed', 'storage.clearFailed', 'source.urlRequired',
+    'shared:labels.thumbnailMissing']
+
+
+// Keep stored and compared messages intact; translate only recognised UI messages at display time.
+export const renderPostImportMessage = (value: string, locale: string): ReactNode => {
+  for (const reference of IMPORT_MESSAGE_KEYS)
+  {
+    const [namespace, key] =
+	reference.includes (':')
+	? reference.split (':')
+	: ['imports', reference]
+    const template: unknown = i18n.getResource ('ja', namespace, key)
+    if (typeof template !== 'string')
+      continue
+    const names = [...template.matchAll (/\{\{(\w+)\}\}/g)].map (match => match[1])
+    const pattern = template.split (/(\{\{\w+\}\})/).map (part =>
+	part.startsWith ('{{')
+	? '(\\d+)'
+	: part.replace (/[.*+?^${}()|[\]\\]/g, '\\$&')).join ('')
+    const match = value.match (new RegExp (`^${pattern}$`))
+    if (match == null)
+      continue
+    const values = Object.fromEntries (names.map ((name, index) => [name, match[index + 1]]))
+    const result = translateUIMessage (key, namespace, locale, values)
+    return createElement (LocalisedText, { language: result.language, children: result.text })
+  }
+  return value
+}
+
 const hasWarnings = (row: PostImportRow): boolean =>
     Object.values (row.fieldWarnings ?? { }).some (messages => messages.length > 0)
     || row.baseWarnings.length > 0

frontend/src/components/ui/dialog.tsx

@@ -3,7 +3,10 @@
 import * as DialogPrimitive from '@radix-ui/react-dialog'
 import { X } from 'lucide-react'
 import * as React from 'react'
+import { useTranslation } from 'react-i18next'
 
+import LocalisedText from '@/components/LocalisedText'
+import { translateUIMessage } from '@/lib/i18n'
 import { cn } from '@/lib/utils'
 
 const Dialog = DialogPrimitive.Root
@@ -34,7 +37,10 @@ const DialogContent = React.forwardRef<
     React.ComponentPropsWithoutRef<typeof DialogPrimitive.Content>
     & { closeLabel?: React.ReactNode }
 >(
-    ({ className, children, closeLabel = '閉ぢる', ...props }, ref) => (
+    ({ className, children, closeLabel, ...props }, ref) => {
+      const { i18n } = useTranslation ('shared')
+      const close = translateUIMessage ('dialogue.close', 'shared', i18n.language)
+      return (
 	  <DialogPortal>
 	    <DialogOverlay/>
 	    <DialogPrimitive.Content
@@ -60,10 +66,14 @@ const DialogContent = React.forwardRef<
 		      'dark:text-slate-400 dark:hover:bg-slate-700 dark:hover:text-slate-50',
 		      'focus:outline-none focus:ring-2 focus:ring-slate-400')}>
 		<X className="h-4 w-4"/>
-	      <span className="sr-only">{closeLabel}</span>
+		<span className="sr-only">
+		  {closeLabel ?? (
+		      <LocalisedText language={close.language}>{close.text}</LocalisedText>)}
+		</span>
 	      </DialogPrimitive.Close>
 	    </DialogPrimitive.Content>
-	</DialogPortal>))
+	  </DialogPortal>)
+    })
 DialogContent.displayName = DialogPrimitive.Content.displayName
 
 const DialogHeader = (

frontend/src/lib/dialogues/useDialogue.ts

@@ -26,7 +26,7 @@ type ChoiceOptions<T extends string> = { title:         ReactNode
 					 closeLabel?:   ReactNode }
 
 type DialogueFormAction = {
-  label:      string
+  label:      ReactNode
   placement?: 'start' | 'end'
   variant?:   DialogueVariant
   disabled?:  boolean
@@ -37,10 +37,10 @@ type DialogueFormControls = {
   setActions: (actions: DialogueFormAction[]) => void
   confirm:    (options: ConfirmOptions) => Promise<boolean> }
 
-type DialogueFormOptions = { title:         string
+type DialogueFormOptions = { title:         ReactNode
 			     description?:  ReactNode
 			     body:          (controls: DialogueFormControls) => ReactNode
-			     cancelText?:   string
+			     cancelText?:   ReactNode
 			     size?:         'default' | 'large' }
 
 type DialogueAPI =

frontend/src/lib/postImportSourceValidation.ts

@@ -1,3 +1,5 @@
+import { translateUIMessage } from '@/lib/i18n'
+
 import type { PostImportSourceIssue } from '@/lib/postImportTypes'
 
 const MAX_ROWS = 100
@@ -67,7 +69,8 @@ export const validateImportSource = (
         {
           issues.push ({
               sourceRow,
-              message: `取込件数は ${ MAX_ROWS } 件までです．`,
+              message: translateUIMessage ('validation.tooMany', 'imports', 'ja', {
+		  count: MAX_ROWS }).text,
               url: displayUrl })
           return
         }
@@ -75,7 +78,7 @@ export const validateImportSource = (
         {
           issues.push ({
               sourceRow,
-              message: 'URL が長すぎます．',
+              message: translateUIMessage ('validation.urlTooLong', 'imports', 'ja').text,
               url: displayUrl })
           return
         }
@@ -84,7 +87,7 @@ export const validateImportSource = (
         {
           issues.push ({
               sourceRow,
-              message: 'URL の形式が不正です．',
+              message: translateUIMessage ('validation.invalidUrl', 'imports', 'ja').text,
               url: displayUrl })
           return
         }
@@ -92,7 +95,7 @@ export const validateImportSource = (
         {
           issues.push ({
               sourceRow,
-              message: 'HTTP または HTTPS の URL ではありません．',
+              message: translateUIMessage ('validation.protocol', 'imports', 'ja').text,
               url: displayUrl })
           return
         }
@@ -100,7 +103,7 @@ export const validateImportSource = (
         {
           issues.push ({
               sourceRow,
-              message: 'URL の形式が不正です．',
+              message: translateUIMessage ('validation.invalidUrl', 'imports', 'ja').text,
               url: displayUrl })
           return
         }
@@ -110,7 +113,8 @@ export const validateImportSource = (
         {
           issues.push ({
               sourceRow,
-              message: `${ duplicateRow } 行目と同じ URL です．`,
+              message: translateUIMessage ('validation.duplicateRow', 'imports', 'ja', {
+		  row: duplicateRow }).text,
               url: displayUrl })
           return
         }

frontend/src/lib/postImportStorage.ts

@@ -1,3 +1,5 @@
+import { translateUIMessage } from '@/lib/i18n'
+
 import type { StorageErrorHandler } from '@/lib/postImportTypes'
 
 const SOURCE_DRAFT_KEY = 'post-import-source-draft'
@@ -16,7 +18,7 @@ const readStorage = (
   }
   catch
   {
-    onError?.('保存済みデータを読み込めませんでした．')
+    onError?.(translateUIMessage ('storage.readFailed', 'imports', 'ja').text)
     return null
   }
 }
@@ -37,7 +39,7 @@ const writeStorage = (
   }
   catch
   {
-    onError?.('ブラウザへ保存できませんでした．')
+    onError?.(translateUIMessage ('storage.writeFailed', 'imports', 'ja').text)
     return false
   }
 }
@@ -56,7 +58,7 @@ const removeStorage = (
   }
   catch
   {
-    onError?.('保存済みデータを削除できませんでした．')
+    onError?.(translateUIMessage ('storage.clearFailed', 'imports', 'ja').text)
   }
 }
 

frontend/src/lib/useUITranslation.ts

@@ -1,4 +1,4 @@
-import { createElement } from 'react'
+import { createElement, useCallback } from 'react'
 import { useTranslation } from 'react-i18next'
 
 import LocalisedText from '@/components/LocalisedText'
@@ -10,15 +10,15 @@ export const useUITranslation = (namespace = 'common') => {
   const locale = useLocale ()
   useTranslation (namespace, { lng: locale })
 
-  const message = (key: string, values?: Record<string, string | number>) => {
+  const message = useCallback ((key: string, values?: Record<string, string | number>) => {
     return translateUIMessage (key, namespace, locale, values)
-  }
+  }, [namespace, locale])
 
-  const label = (key: string, values?: Record<string, string | number>) => {
+  const label = useCallback ((key: string, values?: Record<string, string | number>) => {
     const result = message (key, values)
     return createElement (LocalisedText, {
 	language: result.language, children: result.text })
-  }
+  }, [message])
 
   return { message, label }
 }

frontend/src/locales/ain-Kana/common.json

@@ -1,4 +1,5 @@
-{ "countLabel": "チピㇱキㇷ゚",
+{ "loadingLabel": "$t(common:loading)",
+  "countLabel": "チピㇱキㇷ゚",
   "categoryLabel": "イソネカ",
   "stateLabel": "シㇼキ",
   "search": "イフナラ",

frontend/src/locales/ain-Kana/gekanator.json

@@ -1,8 +1,5 @@
-{
+{ "unavailable": {
-  "unavailable": {
       "title": "Gekanator　タネ　シサㇺ　イタㇰ　アニ　パテㇰ　エシノッ　エアㇱカイ！",
       "back": "ホㇱキ　ソㇱ　ウン　ホㇱピ",
       "switchToJapanese": "シサㇺ　イタㇰ　ウン　シンナ",
-    "imageAlt": "ポロンノ　チㇱ　コㇿ　アン　洗澡鹿"
+      "imageAlt": "ポロンノ　チㇱ　コㇿ　アン　シチャウカ　ユㇰ　ニチカ" } }
-  }
-}

frontend/src/locales/ain-Kana/history.json

@@ -1,4 +1,6 @@
-{ "postTitle": "$t(tags:history)",
+{ "_untranslated": ["exportPath"],
+  "exportPath": "export_path",
+  "postTitle": "$t(tags:history)",
   "tagTitle": "タㇰ　イヌイェㇷ゚　フㇱコアンペ",
   "materialTitle": "チカㇻペ　フㇱコアンペ",
   "postPrefix": "：ミンタㇻ　",

frontend/src/locales/ain-Kana/imports.json

@@ -1,4 +1,26 @@
-{ "status": {
+{ "_untranslated": ["source", "review", "validation", "storage"],
+  "source": {
+    "title": "広場に投稿を追加", "urls": "URL リスト（1 行 1 URL）",
+    "restoreFailed": "保存済み入力を復元できませんでした", "saveFailed": "入力内容を保存できませんでした",
+    "urlRequired": "URL を入力してください．", "rowPrefix": "{{row}} 行目: ",
+    "lineCount": "入力行数 {{count}} / {{limit}}", "next": "次へ" },
+  "review": {
+    "title": "追加内容確認", "clearFailed": "入力内容を削除できませんでした",
+    "validateFailed": "行の再検証に失敗しました", "editPost": "投稿を編輯",
+    "incomplete": "登録結果が不完全でした", "retryFailed": "再試行に失敗しました",
+    "submitFailed": "登録に失敗しました", "existingSkipped": "既存投稿による自動スキップ {{count}}件",
+    "creatable": "作成対象 {{count}}件", "manualSkipped": "手動スキップ {{count}}件",
+    "pending": "未処理 {{count}}件", "back": "戻る", "addAll": "一括追加",
+    "reset": "変更をリセット", "save": "編輯内容を保存", "duration": "動画時間 {{duration}}" },
+  "validation": {
+    "duplicateUrl": "URL が重複しています．", "processingFailed": "登録中にエラーが発生しました．",
+    "tooMany": "取込件数は {{count}} 件までです．", "urlTooLong": "URL が長すぎます．",
+    "invalidUrl": "URL の形式が不正です．", "protocol": "HTTP または HTTPS の URL ではありません．",
+    "duplicateRow": "{{row}} 行目と同じ URL です．" },
+  "storage": {
+    "readFailed": "保存済みデータを読み込めませんでした．", "writeFailed": "ブラウザへ保存できませんでした．",
+    "clearFailed": "保存済みデータを削除できませんでした．" },
+  "status": {
       "ready": "アオ　エアㇱカイ",
       "error": "アオ　エアイカㇷ゚",
       "warning": "イパㇰカㇱヌ",

frontend/src/locales/ain-Kana/navigation.json

@@ -1,4 +1,5 @@
-{ "posts": "ミンタㇻ",
+{ "menuToggle": "$t(shared:labels.menu)",
+  "posts": "ミンタㇻ",
   "postsWithCount": "ミンタㇻ（{{count}}）",
   "list": "オピッタ",
   "search": "イフナラ",

frontend/src/locales/ain-Kana/posts.json

@@ -1,4 +1,23 @@
-{ "edit": { "validationFailed": "アシㇼ　カㇻ　カ　エアイカㇷ゚……",
+{ "_untranslated": ["list", "search", "detail", "embed"],
+  "list": {
+    "tagline": "{{brand}}　〜 ぼざろクリーチャーシリーズ綜合リンク集サイト",
+    "empty": "広場には何もありませんよ．", "viewWiki": "Wiki を見る",
+    "and": " and ", "or": " or " },
+  "search": {
+    "title": "広場検索", "matchType": "検索区分：", "all": "AND", "any": "OR",
+    "createdAt": "投稿日時" },
+  "detail": {
+    "networkFailed": "通信に失敗しました……",
+    "children": "この投稿には {{count}} 件の子投稿があります．",
+    "parent": "この投稿には 1 件の親投稿があります．",
+    "parentAndSiblings": "この投稿には 1 件の親投稿と {{count}} 件の姉妹投稿があります．",
+    "viewed": "閲覧済", "unviewed": "未閲覧", "emptyRelated": "まだないよ（笑）" },
+  "embed": {
+    "openExternal": "外部ページを開く", "load": "埋め込みを読込",
+    "confirmTitle": "未確認の外部ページを表示します。",
+    "risk": "悪意のあるスクリプトが実行される可能性があります。",
+    "question": "表示しますか?", "showExternal": "外部ページを表示" },
+  "edit": { "validationFailed": "アシㇼ　カㇻ　カ　エアイカㇷ゚……",
 	    "conflictTitle": "モㇱマ　クㇽ　アシㇼ　カㇻ　ワ　アン！",
 	    "conflictDescription": "モㇱマ　イカㇻ　クㇽ　エエトコ　アシㇼ　カㇻ　ワ　アン。",
 	    "conflictQuestion": "タネ　エカㇻ　シンナ　ペ　ネコン　エキ　クス　ネ　ヤ？",

frontend/src/locales/ain-Kana/shared.json

@@ -1,4 +1,8 @@
-{ "labels": {
+{ "_untranslated": ["dialogue.confirm", "sidebarWidth", "results", "updateFailedMessage"],
+  "dialogue": { "confirm": "確定", "close": "$t(settings:actions.close)" },
+  "sidebarWidth": "サイドバー幅", "url": "URL", "idPrefix": "Id.: ", "results": "検索結果",
+  "updateFailedMessage": "更新に失敗しました．",
+  "labels": {
       "title": "レ",
       "content": "オルㇱペ",
       "body": "ヌイェㇷ゚",

frontend/src/locales/ain-Kana/tags.json

@@ -1,4 +1,22 @@
-{ "title": "タㇰ",
+{ "_untranslated": ["deprecated", "nico", "relations"],
+  "deprecated": "廃止済",
+  "nico": {
+    "discardConfirm": "編集中の内容を破棄しますか?", "discard": "破棄",
+    "updated": "連携を更新しました．", "updateFailed": "更新できませんでした．",
+    "loadFailed": "読込失敗", "loadFailedDescription": "ニコニコ連携を読み込めませんでした．",
+    "description": "ニコニコタグを広場のタグへ結び付けます．",
+    "linkedTags": "連携タグ", "linkStatus": "連携状態",
+    "all": "すべて", "linked": "連携済み", "unlinked": "未連携",
+    "firstRecorded": "最初に記載された日時", "recentRecorded": "最近記載された日時",
+    "edit": "編集", "tagsToLink": "連携する広場タグ",
+    "tagsPlaceholder": "タグ名を空白または改行で区切って入力" },
+  "relations": {
+    "added": "上位タグ対応追加", "removed": "上位タグ対応解除", "failed": "上位タグ対応失敗",
+    "addedDescription": "《{{child}}》を《{{parent}}》の子タグに設定しました．",
+    "removedDescription": "《{{child}}》を《{{parent}}》の子タグから外しました．",
+    "categoryChanged": "《{{name}}》のカテゴリを変更しました．",
+    "permissionRequired": "独裁者である必要があります．" },
+  "title": "タㇰ",
   "name": "レ",
   "postCount": "ミンタㇻ　アオ　ペ　チピㇱキㇷ゚",
   "firstRecordedAt": "ホㇱキ　アヌイェ　ト　ヘㇺ　トキ",

frontend/src/locales/ja/common.json

@@ -1,4 +1,5 @@
 {
+  "loadingLabel": "Loading",
   "countLabel": "件数",
   "categoryLabel": "カテゴリ",
   "stateLabel": "状態",

frontend/src/locales/ja/history.json

@@ -1,4 +1,5 @@
 {
+  "exportPath": "export_path",
   "postTitle": "耕作履歴",
   "tagTitle": "タグ定義変更履歴",
   "materialTitle": "素材履歴",

frontend/src/locales/ja/imports.json

@@ -1,4 +1,29 @@
 {
+  "source": {
+    "title": "広場に投稿を追加", "urls": "URL リスト（1 行 1 URL）",
+    "restoreFailed": "保存済み入力を復元できませんでした", "saveFailed": "入力内容を保存できませんでした",
+    "urlRequired": "URL を入力してください．", "rowPrefix": "{{row}} 行目: ",
+    "lineCount": "入力行数 {{count}} / {{limit}}", "next": "次へ"
+  },
+  "review": {
+    "title": "追加内容確認", "clearFailed": "入力内容を削除できませんでした",
+    "validateFailed": "行の再検証に失敗しました", "editPost": "投稿を編輯",
+    "incomplete": "登録結果が不完全でした", "retryFailed": "再試行に失敗しました",
+    "submitFailed": "登録に失敗しました", "existingSkipped": "既存投稿による自動スキップ {{count}}件",
+    "creatable": "作成対象 {{count}}件", "manualSkipped": "手動スキップ {{count}}件",
+    "pending": "未処理 {{count}}件", "back": "戻る", "addAll": "一括追加",
+    "reset": "変更をリセット", "save": "編輯内容を保存", "duration": "動画時間 {{duration}}"
+  },
+  "validation": {
+    "duplicateUrl": "URL が重複しています．", "processingFailed": "登録中にエラーが発生しました．",
+    "tooMany": "取込件数は {{count}} 件までです．", "urlTooLong": "URL が長すぎます．",
+    "invalidUrl": "URL の形式が不正です．", "protocol": "HTTP または HTTPS の URL ではありません．",
+    "duplicateRow": "{{row}} 行目と同じ URL です．"
+  },
+  "storage": {
+    "readFailed": "保存済みデータを読み込めませんでした．", "writeFailed": "ブラウザへ保存できませんでした．",
+    "clearFailed": "保存済みデータを削除できませんでした．"
+  },
   "status": {
     "ready": "登録可能", "error": "登録不可", "warning": "警告",
     "skipped": "スキップ", "created": "登録済み", "failed": "登録失敗"

frontend/src/locales/ja/navigation.json

@@ -1,4 +1,5 @@
-{ "posts": "広場",
+{ "menuToggle": "Menu",
+  "posts": "広場",
   "postsWithCount": "広場 ({{count}})",
   "list": "一覧",
   "search": "検索",

frontend/src/locales/ja/posts.json

@@ -1,4 +1,26 @@
 {
+  "list": {
+    "tagline": "{{brand}}　〜 ぼざろクリーチャーシリーズ綜合リンク集サイト",
+    "empty": "広場には何もありませんよ．", "viewWiki": "Wiki を見る",
+    "and": " and ", "or": " or "
+  },
+  "search": {
+    "title": "広場検索", "matchType": "検索区分：", "all": "AND", "any": "OR",
+    "createdAt": "投稿日時"
+  },
+  "detail": {
+    "networkFailed": "通信に失敗しました……",
+    "children": "この投稿には {{count}} 件の子投稿があります．",
+    "parent": "この投稿には 1 件の親投稿があります．",
+    "parentAndSiblings": "この投稿には 1 件の親投稿と {{count}} 件の姉妹投稿があります．",
+    "viewed": "閲覧済", "unviewed": "未閲覧", "emptyRelated": "まだないよ（笑）"
+  },
+  "embed": {
+    "openExternal": "外部ページを開く", "load": "埋め込みを読込",
+    "confirmTitle": "未確認の外部ページを表示します。",
+    "risk": "悪意のあるスクリプトが実行される可能性があります。",
+    "question": "表示しますか?", "showExternal": "外部ページを表示"
+  },
   "edit": {
     "validationFailed": "更新はできなかったよ……",
     "conflictTitle": "競合が発生しました．",

frontend/src/locales/ja/shared.json

@@ -1,4 +1,10 @@
 {
+  "dialogue": { "confirm": "確定", "close": "閉ぢる" },
+  "sidebarWidth": "サイドバー幅",
+  "url": "URL",
+  "idPrefix": "Id.: ",
+  "results": "検索結果",
+  "updateFailedMessage": "更新に失敗しました．",
   "labels": {
     "title": "タイトル", "content": "内容", "body": "本文",
     "lastUpdated": "最終更新", "thumbnail": "サムネール",

frontend/src/locales/ja/tags.json

@@ -1,4 +1,23 @@
-{ "title": "タグ",
+{ "deprecated": "廃止済",
+  "nico": {
+    "discardConfirm": "編集中の内容を破棄しますか?", "discard": "破棄",
+    "updated": "連携を更新しました．", "updateFailed": "更新できませんでした．",
+    "loadFailed": "読込失敗", "loadFailedDescription": "ニコニコ連携を読み込めませんでした．",
+    "description": "ニコニコタグを広場のタグへ結び付けます．",
+    "linkedTags": "連携タグ", "linkStatus": "連携状態",
+    "all": "すべて", "linked": "連携済み", "unlinked": "未連携",
+    "firstRecorded": "最初に記載された日時", "recentRecorded": "最近記載された日時",
+    "edit": "編集", "tagsToLink": "連携する広場タグ",
+    "tagsPlaceholder": "タグ名を空白または改行で区切って入力"
+  },
+  "relations": {
+    "added": "上位タグ対応追加", "removed": "上位タグ対応解除", "failed": "上位タグ対応失敗",
+    "addedDescription": "《{{child}}》を《{{parent}}》の子タグに設定しました．",
+    "removedDescription": "《{{child}}》を《{{parent}}》の子タグから外しました．",
+    "categoryChanged": "《{{name}}》のカテゴリを変更しました．",
+    "permissionRequired": "独裁者である必要があります．"
+  },
+  "title": "タグ",
   "name": "名前",
   "postCount": "広場の投稿数",
   "firstRecordedAt": "はじめて記載された日時",

frontend/src/pages/deerjikists/DeerjikistDetailPage.tsx

@@ -83,7 +83,7 @@ const DeerjikistDetailPage: FC = () => {
 
   return (
       <MainArea>
-	{(loading || !(tag)) ? 'Loading...' : (
+	{(loading || !(tag)) ? label ('common:loading') : (
 	    <div className="max-w-xl">
 	      <PageTitle>
 		<TagLink tag={tag} withWiki={false} withCount={false}/>

frontend/src/pages/help/HelpDiffPage.tsx

@@ -20,7 +20,7 @@ const markers = { added: '+ ', removed: '- ', unchanged: '  ' }
 
 
 const HelpDiffPage: FC = () => {
-  const { message } = useUITranslation ('help')
+  const { message, label } = useUITranslation ('help')
   const locale = useLocale ()
   const { identifier = '' } = useParams ()
   const [searchParams] = useSearchParams ()
@@ -85,7 +85,7 @@ const HelpDiffPage: FC = () => {
 		</code>
 	      </pre>
 	    </>)
-	 : <div>Loading...</div>}
+	 : <div>{label ('common:loading')}</div>}
       </MainArea>)
 }
 

frontend/src/pages/materials/MaterialDetailPage.tsx

@@ -132,7 +132,7 @@ const MaterialDetailPage: FC = () => {
 
 	      <TabGroup>
 		{material.tag && (
-		    <Tab name="Wiki">
+		    <Tab name={label ('navigation:wiki')}>
 		      <WikiBody
 			  title={material.tag.name}
 			  body={material.wikiPageBody ?? undefined}/>

frontend/src/pages/materials/MaterialHistoryPage.tsx

@@ -160,8 +160,8 @@ const MaterialHistoryPage: FC = () => {
 			<th className="p-2 text-left">{label ('version')}</th>
 			<th className="p-2 text-left">{label ('tagName')}</th>
 			<th className="p-2 text-left">{label ('filename')}</th>
-			<th className="p-2 text-left">URL</th>
+			<th className="p-2 text-left">{label ('shared:url')}</th>
-			<th className="p-2 text-left">export_path</th>
+			<th className="p-2 text-left">{label ('exportPath')}</th>
 			<th className="p-2 text-left">{label ('actor')}</th>
 		      </tr>
 		    </thead>

frontend/src/pages/posts/PostDetailPage.tsx

@@ -19,6 +19,7 @@ import { postsKeys, tagsKeys } from '@/lib/queryKeys'
 import { useClientBehaviourSettings } from '@/lib/useClientBehaviourSettings'
 import { canEditContent } from '@/lib/users'
 import { cn } from '@/lib/utils'
+import { useUITranslation } from '@/lib/useUITranslation'
 import NotFound from '@/pages/NotFound'
 import ServiceUnavailable from '@/pages/ServiceUnavailable'
 
@@ -31,6 +32,7 @@ type Props = { user: User | null }
 
 const PostDetailPage: FC<Props> = ({ user }) => {
   const locale = useLocale ()
+  const { label } = useUITranslation ('posts')
   const editable = canEditContent (user)
   const behaviourSettings = useClientBehaviourSettings ()
   const thumbnailMode = behaviourSettings.thumbnailMode ?? 'normal'
@@ -72,7 +74,8 @@ const PostDetailPage: FC<Props> = ({ user }) => {
       onError: (...[, , ctx]) => {
 	if (ctx?.prev)
 	  qc.setQueryData (postKey, ctx.prev)
-	toast ({ title: '失敗……', description: '通信に失敗しました……' })
+	toast ({ title: label ('shared:messages.failed'),
+	    description: label ('detail.networkFailed') })
       },
       onSuccess: () => {
 	qc.invalidateQueries ({ queryKey: postsKeys.root })} })
@@ -122,7 +125,7 @@ const PostDetailPage: FC<Props> = ({ user }) => {
 	      <>
 		{(post.childPosts ?? []).length > 0 && (
 		    <div className="mb-4 bg-green-200 dark:bg-green-800 text-sm p-2 rounded-md">
-		      <p>この投稿には {post.childPosts!.length} 件の子投稿があります．</p>
+		      <p>{label ('detail.children', { count: post.childPosts!.length })}</p>
 		      <PostList posts={[{ ...post, childPosts: [{ } as Post] },
 					...post.childPosts!.map (p => ({
 					    ...p, parentPosts: [{ } as Post] }))]}/>
@@ -137,9 +140,9 @@ const PostDetailPage: FC<Props> = ({ user }) => {
 			  key={pp.id}
 			  className="mb-4 bg-yellow-200 dark:bg-yellow-800 text-sm p-2 rounded-md">
 			<p>
-			  この投稿には 1 件の親投稿{
+			  {siblings.length > 1
-			      siblings.length > 1
+			   ? label ('detail.parentAndSiblings', { count: siblings.length - 1 })
-			      && `と ${ siblings.length - 1 } 件の姉妹投稿`}があります．
+			   : label ('detail.parent')}
 			</p>
 			<PostList posts={[{ ...pp, childPosts: [{ } as Post] },
 					  ...siblings.map (p => ({
@@ -170,16 +173,16 @@ const PostDetailPage: FC<Props> = ({ user }) => {
 		<Button onClick={() => changeViewedFlg.mutate (!(post.viewed))}
 			disabled={changeViewedFlg.isPending}
 			className={cn ('text-white', viewedClass)}>
-		  {post.viewed ? '閲覧済' : '未閲覧'}
+		  {label (post.viewed ? 'detail.viewed' : 'detail.unviewed')}
 		</Button>
 		<TabGroup>
-		  <Tab name="関聯">
+		  <Tab name={label ('shared:labels.relations')}>
 		    {post.related.length > 0
 		     ? <PostList posts={post.related}/>
-		     : 'まだないよ（笑）'}
+		     : label ('detail.emptyRelated')}
 		  </Tab>
 		  {editable && (
-		      <Tab name="編輯">
+		      <Tab name={label ('shared:actions.edit')}>
 			<PostEditForm
 			    post={post}
 			 onSave={newPost => {
@@ -191,7 +194,7 @@ const PostDetailPage: FC<Props> = ({ user }) => {
 		      </Tab>)}
 		</TabGroup>
 	      </>)
-	   : 'Loading...'}
+	   : label ('common:loading')}
 	</MainArea>
 
 	{post && <TagDetailSidebar post={post} sp className="md:hidden"/>}

frontend/src/pages/posts/PostHistoryPage.tsx

@@ -195,7 +195,7 @@ const PostHistoryPage: FC = () => {
 		      <th className="p-2 text-left">{label ('post')}</th>
 		      <th className="p-2 text-left">{label ('version')}</th>
 		      <th className="p-2 text-left">{label ('shared:labels.title')}</th>
-		      <th className="p-2 text-left">URL</th>
+		      <th className="p-2 text-left">{label ('shared:url')}</th>
 		      <th className="p-2 text-left">{label ('navigation:tags')}</th>
 		      {/* TODO: 親投稿の履歴 */}
 		      {/* <th className="p-2 text-left">親投稿</th> */}

frontend/src/pages/posts/PostImportReviewPage.tsx

@@ -11,10 +11,13 @@ import PrefetchLink from '@/components/PrefetchLink'
 import PostThumbnailPreview from '@/components/posts/PostThumbnailPreview'
 import PostImportRowForm from '@/components/posts/import/PostImportRowForm'
 import PostImportRowSummary from '@/components/posts/import/PostImportRowSummary'
+import { renderPostImportMessage } from '@/components/posts/import/postImportRowStatus'
 import { Button } from '@/components/ui/button'
 import { toast } from '@/components/ui/use-toast'
 import { SITE_TITLE } from '@/config'
 import { apiGet, apiPost, isApiError } from '@/lib/api'
+import { translateUIMessage } from '@/lib/i18n'
+import { useUITranslation } from '@/lib/useUITranslation'
 import useDialogue from '@/lib/dialogues/useDialogue'
 import { parsePostNewReviewUrls } from '@/lib/postNewQueryState'
 import { validateImportSource } from '@/lib/postImportSourceValidation'
@@ -100,8 +103,9 @@ type ExistingSkippedRowsProps = {
   id:   string
   rows: PostImportRow[] }
 
-const DUPLICATE_URL_MESSAGE = 'URL が重複しています．'
+const DUPLICATE_URL_MESSAGE = translateUIMessage ('validation.duplicateUrl', 'imports', 'ja').text
-const BULK_PROCESSING_FAILED_MESSAGE = '登録中にエラーが発生しました．'
+const BULK_PROCESSING_FAILED_MESSAGE =
+    translateUIMessage ('validation.processingFailed', 'imports', 'ja').text
 
 const emptyAttributes = () => ({
     title: '',
@@ -597,6 +601,7 @@ const editableRowDirty = (row: PostImportRow): boolean =>
 
 const PostImportReviewPage: FC<Props> = ({ user }) => {
   const locale = useLocale ()
+  const { message, label } = useUITranslation ('imports')
   const editable = canEditContent (user)
   const dialogue = useDialogue ()
   const location = useLocation ()
@@ -651,9 +656,10 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
   const finishImport = useCallback (() => {
     allowNextNavigation ()
     clearPostImportSourceDraft (message =>
-	toast ({ title: '入力内容を削除できませんでした', description: message }))
+	toast ({ title: label ('review.clearFailed'),
+	    description: renderPostImportMessage (message, locale) }))
     navigate ('/posts')
-  }, [allowNextNavigation, navigate])
+  }, [allowNextNavigation, navigate, label, locale])
 
   useEffect (() => {
     const urls = parsePostNewReviewUrls (location.search)
@@ -912,7 +918,7 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
 	  return { saved: false, row: applyThumbnailWarning (errorRow) }
 	}
 
-      toast ({ title: '行の再検証に失敗しました' })
+      toast ({ title: label ('review.validateFailed') })
       return { saved: false, row: null }
     }
   }
@@ -926,8 +932,8 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
 	saveDraft (row, { draft, resetRequested })
 
     await dialogue.form ({
-	title: '投稿を編輯',
+	title: label ('review.editPost'),
-	cancelText: '取消',
+	cancelText: label ('shared:actions.cancel'),
 	size: 'large',
 	body: controls => (
 	    <PostImportRowForm
@@ -980,7 +986,7 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
       if (result.results.length !== 1)
 	{
 	  updateRows (currentRows => replaceImportRow (currentRows, originalRow))
-	  toast ({ title: '登録結果が不完全でした' })
+	  toast ({ title: label ('review.incomplete') })
 	  return
 	}
 
@@ -995,7 +1001,7 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
     catch
     {
       updateRows (currentRows => replaceImportRow (currentRows, originalRow))
-      toast ({ title: '再試行に失敗しました' })
+      toast ({ title: label ('review.retryFailed') })
     }
     finally
     {
@@ -1023,7 +1029,7 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
 	  buildBulkFormData (latestProcessingRows), { locale })
       if (result.results.length !== latestProcessingRows.length)
 	{
-	  toast ({ title: '登録結果が不完全でした' })
+	  toast ({ title: label ('review.incomplete') })
 	  return
 	}
 
@@ -1037,7 +1043,7 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
     }
     catch
     {
-      toast ({ title: '登録に失敗しました' })
+      toast ({ title: label ('review.submitFailed') })
     }
     finally
     {
@@ -1054,12 +1060,12 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
   return (
       <>
 	<Helmet>
-	  <title>{`追加内容確認 | ${ SITE_TITLE }`}</title>
+	  <title>{message ('review.title').text} | {SITE_TITLE}</title>
 	</Helmet>
 
 	<MainArea className="pb-40">
 	  <div className="mx-auto max-w-6xl space-y-6">
-	    <PageTitle>追加内容確認</PageTitle>
+	    <PageTitle>{label ('review.title')}</PageTitle>
 
 	    {existingRows.length > 0 && (
 		<div className="rounded-lg border p-4">
@@ -1078,7 +1084,7 @@ const PostImportReviewPage: FC<Props> = ({ user }) => {
 			      ? ''
 			      : 'transition-transform')}/>
 		    </span>
-		    既存投稿による自動スキップ {counts.existingSkipped}件
+		    {label ('review.existingSkipped', { count: counts.existingSkipped })}
 		  </button>
 		  <AnimatePresence initial={false}>
 		    {showExistingRows && (
@@ -1156,17 +1162,19 @@ const PostImportFooter = (
 		    pendingOrErrorCount:  number
 		    onBack:               () => void
 		    onSubmit:             () => void },
-) => (
+) => {
+  const { label } = useUITranslation ('imports')
+  return (
       <div
 	  className="shrink-0 border-t bg-white/95 p-4 backdrop-blur
 		     dark:border-neutral-700 dark:bg-neutral-950/95">
 	<div className="mx-auto flex max-w-6xl flex-col gap-3 md:flex-row
 			md:items-center md:justify-between">
 	  <div className="flex flex-wrap items-center gap-2 text-sm">
-	  <span>作成対象 {creatableCount}件</span>
+	    <span>{label ('review.creatable', { count: creatableCount })}</span>
-	  <span>手動スキップ {manualSkippedCount}件</span>
+	    <span>{label ('review.manualSkipped', { count: manualSkippedCount })}</span>
-	  <span>既存投稿による自動スキップ {existingSkippedCount}件</span>
+	    <span>{label ('review.existingSkipped', { count: existingSkippedCount })}</span>
-	  <span>未処理 {pendingOrErrorCount}件</span>
+	    <span>{label ('review.pending', { count: pendingOrErrorCount })}</span>
 	  </div>
 	  <div className="flex flex-col gap-2 md:flex-row">
 	    <Button
@@ -1175,17 +1183,18 @@ const PostImportFooter = (
 		className="w-full md:w-auto"
 		onClick={onBack}
 		disabled={submitting}>
-	    戻る
+	      {label ('review.back')}
 	    </Button>
 	    <Button
 		type="button"
 		className="w-full md:w-auto"
 		onClick={onSubmit}
 		disabled={metadataLoading || submitting || busyRowsPresent || !(canSubmit)}>
-	    {creatableCount > 1 ? '一括追加' : '追加'}
+	      {creatableCount > 1 ? label ('review.addAll') : label ('shared:actions.add')}
 	    </Button>
 	  </div>
 	</div>
       </div>)
+}
 
 export default PostImportReviewPage

frontend/src/pages/posts/PostImportSourcePage.tsx

@@ -2,7 +2,9 @@ import { useEffect, useRef, useState } from 'react'
 import { Helmet } from 'react-helmet-async'
 
 
-import { useLocaleNavigate } from '@/lib/useLocale'
+import { useLocale, useLocaleNavigate } from '@/lib/useLocale'
+import { useUITranslation } from '@/lib/useUITranslation'
+import { renderPostImportMessage } from '@/components/posts/import/postImportRowStatus'
 import FieldError from '@/components/common/FieldError'
 import Form from '@/components/common/Form'
 import FormField from '@/components/common/FormField'
@@ -40,6 +42,8 @@ const SOURCE_ISSUES_ID = 'post-import-source-issues'
 
 
 const PostImportSourcePage: FC<Props> = ({ user }) => {
+  const locale = useLocale ()
+  const { message: uiMessage, label } = useUITranslation ('imports')
   const editable = canEditContent (user)
   const navigate = useLocaleNavigate ()
   const [source, setSource] = useState ('')
@@ -52,7 +56,7 @@ const PostImportSourcePage: FC<Props> = ({ user }) => {
   const lineCount = countImportSourceLines (source)
   const sourceUrls = extractImportSourceUrls (source)
   const withinPathLimit = isPostNewReviewPathWithinLimit (sourceUrls)
-  const messages = sourceError != null ? [sourceError] : []
+  const messages = sourceError != null ? [label ('source.urlRequired')] : []
   const sourceDescribedBy =
       [sourceError != null ? SOURCE_ERROR_ID : null,
        sourceIssues.length > 0 ? SOURCE_ISSUES_ID : null]
@@ -61,7 +65,8 @@ const PostImportSourcePage: FC<Props> = ({ user }) => {
 
   useEffect (() => {
     const draft = loadPostImportSourceDraft (message =>
-	toast ({ title: '保存済み入力を復元できませんでした', description: message }))
+	toast ({ title: label ('source.restoreFailed'),
+	    description: renderPostImportMessage (message, locale) }))
 
     if (!(editedRef.current))
       {
@@ -70,7 +75,7 @@ const PostImportSourcePage: FC<Props> = ({ user }) => {
 	    ? draft.source
 	    : current)
       }
-  }, [])
+  }, [label, locale])
 
   useEffect (() => {
     if (saveTimer.current != null)
@@ -78,20 +83,21 @@ const PostImportSourcePage: FC<Props> = ({ user }) => {
 
     saveTimer.current = window.setTimeout (() => {
       savePostImportSourceDraft (source, message =>
-	  toast ({ title: '入力内容を保存できませんでした', description: message }))
+	  toast ({ title: label ('source.saveFailed'),
+	      description: renderPostImportMessage (message, locale) }))
     }, 300)
 
     return () => {
       if (saveTimer.current != null)
 	window.clearTimeout (saveTimer.current)
     }
-  }, [source])
+  }, [source, label, locale])
 
   const preview = async () => {
     if (lineCount === 0)
       {
 	setSourceIssues ([])
-	setSourceError ('URL を入力してください．')
+	setSourceError (uiMessage ('source.urlRequired').text)
 	return
       }
 
@@ -124,12 +130,12 @@ const PostImportSourcePage: FC<Props> = ({ user }) => {
   return (
       <MainArea>
 	<Helmet>
-	  <title>{`広場に投稿を追加 | ${ SITE_TITLE }`}</title>
+	  <title>{uiMessage ('source.title').text} | {SITE_TITLE}</title>
 	</Helmet>
 
 	<Form className="max-w-4xl">
-	  <PageTitle>広場に投稿を追加</PageTitle>
+	  <PageTitle>{label ('source.title')}</PageTitle>
-	  <FormField label="URL リスト（1 行 1 URL）">
+	  <FormField label={label ('source.urls')}>
 	    {() => (
 		<TextArea
 		    value={source}
@@ -140,8 +146,8 @@ const PostImportSourcePage: FC<Props> = ({ user }) => {
 		    onBlur={() => {
 		      savePostImportSourceDraft (source, message =>
 			  toast ({
-			      title: '入力内容を保存できませんでした',
+			      title: label ('source.saveFailed'),
-			      description: message }))
+			      description: renderPostImportMessage (message, locale) }))
 		    }}
 		    onChange={ev => {
 		      editedRef.current = true
@@ -158,21 +164,24 @@ const PostImportSourcePage: FC<Props> = ({ user }) => {
 	      className="space-y-2 text-sm text-red-700 dark:text-red-300">
 	    {sourceIssues.map (issue => (
 		<li key={`${ issue.sourceRow }-${ issue.message }-${ issue.url }`}>
-		  <div>{issue.sourceRow} 行目: {issue.message}</div>
+		  <div>
+		    {label ('source.rowPrefix', { row: issue.sourceRow })}
+		    {renderPostImportMessage (issue.message, locale)}
+		  </div>
 		  <div className="break-all font-mono text-xs">{issue.url}</div>
 		</li>))}
 	  </ul>
 
 	  <div className="relative z-10 flex items-center justify-between gap-3">
 	    <div className="text-sm text-neutral-600 dark:text-neutral-300">
-	      入力行数 {lineCount} / {MAX_ROWS}
+	      {label ('source.lineCount', { count: lineCount, limit: MAX_ROWS })}
 	    </div>
 	    <Button
 		type="button"
 		className="pointer-events-auto shrink-0"
 		onClick={preview}
 		disabled={loading || !(withinPathLimit)}>
-	      次へ
+	      {label ('source.next')}
 	    </Button>
 	  </div>
 	</Form>

frontend/src/pages/posts/PostListPage.tsx

@@ -22,6 +22,7 @@ import {
 } from '@/lib/settings'
 import { useKeyboardShortcuts } from '@/lib/useKeyboardShortcuts'
 import { fetchWikiPageByTitle } from '@/lib/wiki'
+import { useUITranslation } from '@/lib/useUITranslation'
 
 import type { FC } from 'react'
 
@@ -35,6 +36,7 @@ const parseLimit = (value: string | null): 20 | 50 | 100 | null => {
 
 const PostListPage: FC = () => {
   const locale = useLocale ()
+  const { message, label } = useUITranslation ('posts')
   const containerRef = useRef<HTMLDivElement | null> (null)
 
   const [wikiPage, setWikiPage] = useState<WikiPage | null> (null)
@@ -130,8 +132,8 @@ const PostListPage: FC = () => {
 	<Helmet>
 	  <title>
 	    {tags.length
-	     ? `${ tags.join (anyFlg ? ' or ' : ' and ') } | ${ SITE_TITLE }`
+	     ? `${ tags.join (message (anyFlg ? 'list.or' : 'list.and').text) } | ${ SITE_TITLE }`
-	     : `${ SITE_TITLE }\u3000〜 ぼざろクリーチャーシリーズ綜合リンク集サイト`}
+	     : message ('list.tagline', { brand: SITE_TITLE }).text}
 	  </title>
 	</Helmet>
 
@@ -147,7 +149,7 @@ const PostListPage: FC = () => {
 	  <TabGroup
 	      rightAddon={
 		  <label className="flex items-center gap-2 text-xs text-muted-foreground">
-		    <span>件数</span>
+		    <span>{label ('common:countLabel')}</span>
 		    <select
 			className="rounded border border-border bg-background px-2 py-1 text-sm
 				   text-foreground"
@@ -162,22 +164,22 @@ const PostListPage: FC = () => {
 		    </select>
 		  </label>
 	      }>
-	    <Tab name="広場">
+	    <Tab name={label ('navigation:posts')}>
 	      {posts.length > 0
 	       ? (
 		  <>
 		    <PostList posts={posts}/>
 		    <Pagination page={page} totalPages={totalPages}/>
 		  </>)
-	       : !(loading) && '広場には何もありませんよ．'}
+	       : !(loading) && label ('list.empty')}
-	      {loading && 'Loading...'}
+	      {loading && label ('common:loading')}
 	    </Tab>
 	    {tags.length === 1 && (
-		<Tab name="Wiki">
+		<Tab name={label ('navigation:wiki')}>
 		  <WikiBody title={tags[0]} body={wikiPage?.body}/>
 		  <div className="my-2">
 		    <PrefetchLink to={`/wiki/${ encodeURIComponent (tags[0]) }`}>
-		      Wiki を見る
+		      {label ('list.viewWiki')}
 		    </PrefetchLink>
 		  </div>
 		</Tab>)}

frontend/src/pages/posts/PostSearchPage.tsx

@@ -6,6 +6,7 @@ import { useLocation } from 'react-router-dom'
 
 import { useLocale, useLocaleNavigate } from '@/lib/useLocale'
 import PrefetchLink from '@/components/PrefetchLink'
+import LocalisedText from '@/components/LocalisedText'
 import SortHeader from '@/components/SortHeader'
 import TagLink from '@/components/TagLink'
 import DateTimeField from '@/components/common/DateTimeField'
@@ -29,7 +30,8 @@ import {
 } from '@/lib/settings'
 import { useClientBehaviourSettings } from '@/lib/useClientBehaviourSettings'
 import { useKeyboardShortcuts } from '@/lib/useKeyboardShortcuts'
-import { dateString, inputClass, originalCreatedAtString } from '@/lib/utils'
+import { localisedDateString, inputClass, originalCreatedAtString } from '@/lib/utils'
+import { useUITranslation } from '@/lib/useUITranslation'
 
 import type { FC, FormEvent } from 'react'
 
@@ -72,6 +74,7 @@ const parseOrder = (value: string | null): FetchPostsOrder | null => {
 
 const PostSearchPage: FC = () => {
   const locale = useLocale ()
+  const { message, label } = useUITranslation ('posts')
   const behaviourSettings = useClientBehaviourSettings ()
   const animationMode = behaviourSettings.animation ?? 'normal'
   const thumbnailTransition = clientAnimationTransition (
@@ -223,14 +226,14 @@ const PostSearchPage: FC = () => {
   return (
       <MainArea>
 	<Helmet>
-	  <title>広場検索 | {SITE_TITLE}</title>
+	  <title>{message ('search.title').text} | {SITE_TITLE}</title>
 	</Helmet>
 
 	<div className="max-w-xl">
 	  <div className="flex flex-wrap items-center justify-between gap-3">
-	    <PageTitle>広場検索</PageTitle>
+	    <PageTitle>{label ('search.title')}</PageTitle>
 	    <label className="flex items-center gap-2 text-xs text-muted-foreground">
-	      <span>件数</span>
+	      <span>{label ('common:countLabel')}</span>
 	      <select
 		  className="rounded border border-border bg-background px-2 py-1 text-sm
 			     text-foreground"
@@ -248,7 +251,7 @@ const PostSearchPage: FC = () => {
 
 	  <form onSubmit={handleSearch} className="space-y-2">
 	    {/* タイトル */}
-	    <FormField label="タイトル">
+	    <FormField label={label ('shared:labels.title')}>
 	      {({ invalid }) => (
 		  <input
 		      type="text"
@@ -259,7 +262,7 @@ const PostSearchPage: FC = () => {
 	    </FormField>
 
 	    {/* URL */}
-	    <FormField label="URL">
+	    <FormField label={label ('shared:url')}>
 	      {({ invalid }) => (
 		  <input
 		      type="text"
@@ -269,7 +272,7 @@ const PostSearchPage: FC = () => {
 	    </FormField>
 
 	    {/* タグ */}
-	    <FormField label="タグ">
+	    <FormField label={label ('navigation:tags')}>
 	      {() => (
 		  <TagInput
 		      includeNico={true}
@@ -278,14 +281,14 @@ const PostSearchPage: FC = () => {
 	    </FormField>
 	    <div>
 	      <fieldset className="w-full my-2">
-		<label>検索区分：</label>
+		<label>{label ('search.matchType')}</label>
 		<label className="mx-2">
 		  <input
 		      type="radio"
 		      name="match-type"
 		      checked={matchType === 'all'}
 		      onChange={() => setMatchType ('all')}/>
-		  AND
+		  {label ('search.all')}
 		</label>
 		<label className="mx-2">
 		  <input
@@ -293,13 +296,13 @@ const PostSearchPage: FC = () => {
 		      name="match-type"
 		      checked={matchType === 'any'}
 		      onChange={() => setMatchType ('any')}/>
-		  OR
+		  {label ('search.any')}
 		</label>
 	      </fieldset>
 	    </div>
 
 	    {/* オリジナルの投稿日時 */}
-	    <FormField label="オリジナルの投稿日時">
+	    <FormField label={label ('history:originalPostedAt')}>
 	      {() => (
 		  <>
 		    <DateTimeField
@@ -313,7 +316,7 @@ const PostSearchPage: FC = () => {
 	    </FormField>
 
 	    {/* 投稿日時 */}
-	    <FormField label="投稿日時">
+	    <FormField label={label ('search.createdAt')}>
 	      {() => (
 		  <>
 		    <DateTimeField
@@ -327,7 +330,7 @@ const PostSearchPage: FC = () => {
 	    </FormField>
 
 	    {/* 更新日時 */}
-	    <FormField label="更新日時">
+	    <FormField label={label ('tags:updatedAt')}>
 	      {() => (
 		  <>
 		    <DateTimeField
@@ -345,13 +348,13 @@ const PostSearchPage: FC = () => {
 	      <button
 		  type="submit"
 		  className="bg-blue-500 text-white px-4 py-2 rounded">
-		検索
+		{label ('common:search')}
 	      </button>
 	    </div>
 	  </form>
 	</div>
 
-	{loading ? 'Loading...' : (results.length > 0 ? (
+	{loading ? label ('common:loading') : (results.length > 0 ? (
 	    <div className="mt-4">
 	      <div className="overflow-x-auto">
 		<table className="w-full min-w-[1200px] table-fixed border-collapse">
@@ -367,40 +370,40 @@ const PostSearchPage: FC = () => {
 
 		  <thead className="border-b-2 border-black dark:border-white">
 		    <tr>
-		      <th className="p-2 text-left whitespace-nowrap">投稿</th>
+		      <th className="p-2 text-left whitespace-nowrap">{label ('history:post')}</th>
 		      <th className="p-2 text-left whitespace-nowrap">
 			<SortHeader<FetchPostsOrderField>
 			    by="title"
-			    label="タイトル"
+			    label={label ('shared:labels.title')}
 			    currentOrder={order}
 			    defaultDirection={defaultDirection}/>
 		      </th>
 		      <th className="p-2 text-left whitespace-nowrap">
 			<SortHeader<FetchPostsOrderField>
 			    by="url"
-			    label="URL"
+			    label={label ('shared:url')}
 			    currentOrder={order}
 			    defaultDirection={defaultDirection}/>
 		      </th>
-		      <th className="p-2 text-left whitespace-nowrap">タグ</th>
+		      <th className="p-2 text-left whitespace-nowrap">{label ('navigation:tags')}</th>
 		      <th className="p-2 text-left whitespace-nowrap">
 			<SortHeader<FetchPostsOrderField>
 			    by="original_created_at"
-			    label="オリジナルの投稿日時"
+			    label={label ('history:originalPostedAt')}
 			    currentOrder={order}
 			    defaultDirection={defaultDirection}/>
 		      </th>
 		      <th className="p-2 text-left whitespace-nowrap">
 			<SortHeader<FetchPostsOrderField>
 			    by="created_at"
-			    label="投稿日時"
+			    label={label ('search.createdAt')}
 			    currentOrder={order}
 			    defaultDirection={defaultDirection}/>
 		      </th>
 		      <th className="p-2 text-left whitespace-nowrap">
 			<SortHeader<FetchPostsOrderField>
 			    by="updated_at"
-			    label="更新日時"
+			    label={label ('tags:updatedAt')}
 			    currentOrder={order}
 			    defaultDirection={defaultDirection}/>
 		      </th>
@@ -445,18 +448,28 @@ const PostSearchPage: FC = () => {
 				</span>))}
 			  </td>
 			  <td className="p-2">
+			    <LocalisedText language={locale}>
 			      {originalCreatedAtString (row.originalCreatedFrom,
-						      row.originalCreatedBefore)}
+				  row.originalCreatedBefore, locale)}
+			    </LocalisedText>
+			  </td>
+			  <td className="p-2">
+			    <LocalisedText language={locale}>
+			      {localisedDateString (row.createdAt, locale)}
+			    </LocalisedText>
+			  </td>
+			  <td className="p-2">
+			    <LocalisedText language={locale}>
+			      {localisedDateString (row.updatedAt, locale)}
+			    </LocalisedText>
 			  </td>
-			  <td className="p-2">{dateString (row.createdAt)}</td>
-			  <td className="p-2">{dateString (row.updatedAt)}</td>
 			</tr>))}
 		  </tbody>
 		</table>
 	      </div>
 
 	      <Pagination page={page} totalPages={totalPages}/>
-	    </div>) : '結果ないよ（笑）')}
+	    </div>) : label ('tags:empty'))}
       </MainArea>)
 }
 

frontend/src/pages/tags/NicoTagListPage.tsx

@@ -12,7 +12,7 @@ import FormField from '@/components/common/FormField'
 import PageTitle from '@/components/common/PageTitle'
 import Pagination from '@/components/common/Pagination'
 import TextArea from '@/components/common/TextArea'
-import { useDialogue } from '@/components/dialogues/DialogueProvider'
+import useDialogue from '@/lib/dialogues/useDialogue'
 import MainArea from '@/components/layout/MainArea'
 import { toast } from '@/components/ui/use-toast'
 import { SITE_TITLE } from '@/config'
@@ -22,7 +22,10 @@ import { clientScrollBehaviour } from '@/lib/clientAnimation'
 import { tagsKeys } from '@/lib/queryKeys'
 import { fetchNicoTags } from '@/lib/tags'
 import { useClientBehaviourSettings } from '@/lib/useClientBehaviourSettings'
-import { cn, dateString, inputClass } from '@/lib/utils'
+import { cn, localisedDateString, inputClass } from '@/lib/utils'
+import LocalisedText from '@/components/LocalisedText'
+import { useUITranslation } from '@/lib/useUITranslation'
+import { translateUIMessage } from '@/lib/i18n'
 import { canEditContent } from '@/lib/users'
 
 import type { FC, FormEvent } from 'react'
@@ -42,6 +45,8 @@ const setIf = (qs: URLSearchParams, key: string, value: string) => {
 
 const NicoTagListPage: FC<Props> = ({ user }) => {
   const locale = useLocale ()
+  const { message, label } = useUITranslation ('tags')
+  const fallbackUpdateError = translateUIMessage ('nico.updateFailed', 'tags', 'ja').text
   const behaviourSettings = useClientBehaviourSettings ()
   const animationMode = behaviourSettings.animation ?? 'normal'
   const dialogue = useDialogue ()
@@ -102,8 +107,8 @@ const NicoTagListPage: FC<Props> = ({ user }) => {
 
     if (editingId != null && editingId !== tag.id && editingChanged
 	&& !(await dialogue.confirm ({
-	  title:       '編集中の内容を破棄しますか?',
+	  title: label ('nico.discardConfirm'),
-	  confirmText: '破棄',
+	  confirmText: label ('nico.discard'),
 	  variant:     'danger'})))
       return
 
@@ -134,7 +139,7 @@ const NicoTagListPage: FC<Props> = ({ user }) => {
       setErrorsByTagId (errors => ({ ...errors, [id]: [] }))
       setEditingId (null)
       await queryClient.invalidateQueries ({ queryKey: tagsKeys.nicoRoot })
-      toast ({ description: '連携を更新しました．' })
+      toast ({ description: label ('nico.updated') })
     }
     catch (e)
     {
@@ -143,8 +148,9 @@ const NicoTagListPage: FC<Props> = ({ user }) => {
 	  ...errors,
 	  [id]: validationError?.fieldErrors.tags
 	      ?? validationError?.baseErrors
-	      ?? ['更新できませんでした．']}))
+	      ?? [fallbackUpdateError]}))
-      toast ({ title: '更新失敗', description: '入力内容を確認してください．' })
+      toast ({ title: label ('shared:messages.updateFailed'),
+	  description: label ('shared:messages.checkInputContent') })
     }
     finally
     {
@@ -173,52 +179,60 @@ const NicoTagListPage: FC<Props> = ({ user }) => {
 
   useEffect (() => {
     if (isError)
-      toast ({ title: '読込失敗', description: 'ニコニコ連携を読み込めませんでした．' })
+    {
-  }, [isError])
+      toast ({ title: label ('nico.loadFailed'),
+	  description: label ('nico.loadFailedDescription') })
+    }
+  }, [isError, label])
 
   return (
       <MainArea>
 	<Helmet>
-	  <title>ニコニコ連携 | {SITE_TITLE}</title>
+	  <title>{message ('navigation:nicoLinks').text} | {SITE_TITLE}</title>
 	</Helmet>
 
 	<div className="max-w-xl">
-	  <PageTitle>ニコニコ連携</PageTitle>
+	  <PageTitle>{label ('navigation:nicoLinks')}</PageTitle>
 	  <p className="mb-4 text-sm text-gray-600 dark:text-gray-300">
-	    ニコニコタグを広場のタグへ結び付けます．
+	    {label ('nico.description')}
 	  </p>
 
 	  <form onSubmit={handleSearch} className="space-y-2">
-	    <FormField label="ニコニコタグ">
+	    <FormField label={label ('common:categories.nico')}>
 	      {({ invalid }) => (
 		  <input
 		      type="text"
-		      aria-label="ニコニコタグ"
+		      aria-label={message ('common:categories.nico').text}
+		      lang={message ('common:categories.nico').language}
 		      value={name}
 		      onChange={e => setName (e.target.value)}
 		      className={inputClass (invalid)}/>)}
 	    </FormField>
 
-	    <FormField label="連携タグ">
+	    <FormField label={label ('nico.linkedTags')}>
 	      {({ invalid }) => (
 		  <input
 		      type="text"
-		      aria-label="連携タグ"
+		      aria-label={message ('nico.linkedTags').text}
+		      lang={message ('nico.linkedTags').language}
 		      value={linkedTag}
 		      onChange={e => setLinkedTag (e.target.value)}
 		      className={inputClass (invalid)}/>)}
 	    </FormField>
 
-	    <FormField label="連携状態">
+	    <FormField label={label ('nico.linkStatus')}>
 	      {({ invalid }) => (
 		  <select
-		      aria-label="連携状態"
+		      aria-label={message ('nico.linkStatus').text}
+		      lang={message ('nico.linkStatus').language}
 		      value={linkStatus}
 		      onChange={e => setLinkStatus (e.target.value as LinkStatus)}
 		      className={inputClass (invalid)}>
-		    <option value="all">すべて</option>
+		    {(['all', 'linked', 'unlinked'] as const).map (value => (
-		    <option value="linked">連携済み</option>
+			<option key={value} value={value}
-		    <option value="unlinked">未連携</option>
+			    lang={message (`nico.${value}`).language}>
+			  {message (`nico.${value}`).text}
+			</option>))}
 		  </select>)}
 	    </FormField>
 
@@ -226,19 +240,21 @@ const NicoTagListPage: FC<Props> = ({ user }) => {
 	      <button
 		  type="submit"
 		  className="rounded bg-blue-500 px-4 py-2 text-white">
-		検索
+		{label ('common:search')}
 	      </button>
 	    </div>
 	  </form>
 	</div>
 
 	{loading
-	 ? 'Loading...'
+	 ? label ('common:loading')
 	 : (
 	    <div className="mt-6">
 	      <div className="mb-3 flex items-baseline justify-between gap-4">
-		<h2 className="text-lg font-bold">検索結果</h2>
+		<h2 className="text-lg font-bold">{label ('shared:results')}</h2>
-		<span className="text-sm text-gray-500 dark:text-gray-400">{count} 件</span>
+		<span className="text-sm text-gray-500 dark:text-gray-400">
+		  {label ('shared:labels.resultsCount', { count })}
+		</span>
 	      </div>
 
 	      {nicoTags.length > 0
@@ -257,22 +273,22 @@ const NicoTagListPage: FC<Props> = ({ user }) => {
 			  <th className="p-2 text-left whitespace-nowrap">
 			    <SortHeader<FetchNicoTagsOrderField>
 				by="name"
-				label="ニコニコタグ"
+				label={label ('common:categories.nico')}
 				currentOrder={order}
 				defaultDirection={defaultDirection}/>
 			  </th>
-			  <th className="p-2 text-left">連携タグ</th>
+			  <th className="p-2 text-left">{label ('nico.linkedTags')}</th>
 			  <th className="p-2 text-left whitespace-nowrap">
 			    <SortHeader<FetchNicoTagsOrderField>
 				by="created_at"
-				label="最初に記載された日時"
+				label={label ('nico.firstRecorded')}
 				currentOrder={order}
 				defaultDirection={defaultDirection}/>
 			  </th>
 			  <th className="p-2 text-left whitespace-nowrap">
 			    <SortHeader<FetchNicoTagsOrderField>
 				by="updated_at"
-				label="最近記載された日時"
+				label={label ('nico.recentRecorded')}
 				currentOrder={order}
 				defaultDirection={defaultDirection}/>
 			  </th>
@@ -282,6 +298,8 @@ const NicoTagListPage: FC<Props> = ({ user }) => {
 		      <tbody>
 			{nicoTags.map (tag => {
 			  const isEditing = editingId === tag.id
+			  const errors = errorsByTagId[tag.id]?.map (value =>
+			      value === fallbackUpdateError ? label ('nico.updateFailed') : value)
 
 			  return (
 			      <Fragment key={tag.id}>
@@ -306,10 +324,15 @@ const NicoTagListPage: FC<Props> = ({ user }) => {
 				    </span>))}
 			      </td>
 			      <td className="p-2 align-top whitespace-nowrap">
-				{dateString (tag.createdAt)}
+				<LocalisedText language={locale}>
+				  {localisedDateString (tag.createdAt, locale)}
+				</LocalisedText>
 			      </td>
 			      <td className="p-2 align-top whitespace-nowrap">
-				{tag.recentPostTagCreatedAt && dateString (tag.recentPostTagCreatedAt)}
+				{tag.recentPostTagCreatedAt && (
+				    <LocalisedText language={locale}>
+				      {localisedDateString (tag.recentPostTagCreatedAt, locale)}
+				    </LocalisedText>)}
 			      </td>
 			      {editable && (
 				  <td className="p-2 text-right align-top">
@@ -320,7 +343,7 @@ const NicoTagListPage: FC<Props> = ({ user }) => {
 					    className="inline-flex items-center gap-1 text-sm text-blue-700
 						       hover:underline dark:text-blue-300">
 					  <Pencil className="size-3.5"/>
-					  編集
+					  {label ('nico.edit')}
 					</button>)}
 				  </td>)}
 			    </tr>
@@ -332,18 +355,19 @@ const NicoTagListPage: FC<Props> = ({ user }) => {
 				    <div className="space-y-2">
 				      <label htmlFor={`nico-links-${ tag.id }`}
 					     className="block text-sm font-semibold">
-					連携する広場タグ
+					{label ('nico.tagsToLink')}
 				      </label>
 				      <TextArea
 					  id={`nico-links-${ tag.id }`}
 					  value={rawTags[tag.id] ?? ''}
 					  invalid={(errorsByTagId[tag.id] ?? []).length > 0}
 					  className="min-h-24 resize-y"
-					  placeholder="タグ名を空白または改行で区切って入力"
+					  placeholder={message ('nico.tagsPlaceholder').text}
+					  lang={message ('nico.tagsPlaceholder').language}
 					  onChange={e => setRawTags (rawTags => ({
 					      ...rawTags,
 					      [tag.id]: e.target.value}))}/>
-				      <FieldError messages={errorsByTagId[tag.id]}/>
+				      <FieldError messages={errors}/>
 				      <div className="flex justify-end gap-2">
 					<button
 					    type="button"
@@ -353,7 +377,7 @@ const NicoTagListPage: FC<Props> = ({ user }) => {
 						       border-gray-300 px-3 py-1.5 text-sm
 						       disabled:opacity-50 dark:border-gray-700">
 					  <X className="size-3.5"/>
-					  取消
+					  {label ('shared:actions.cancel')}
 					</button>
 					<button
 					    type="button"
@@ -364,7 +388,7 @@ const NicoTagListPage: FC<Props> = ({ user }) => {
 					  {savingId === tag.id
 					   ? <LoaderCircle className="size-3.5 animate-spin"/>
 					   : <Check className="size-3.5"/>}
-					  保存
+					  {label ('settings:actions.save')}
 					</button>
 				      </div>
 				    </div>
@@ -375,7 +399,7 @@ const NicoTagListPage: FC<Props> = ({ user }) => {
 		      </tbody>
 		    </table>
 		  </div>)
-	       : <p>結果ないよ（笑）</p>}
+	       : <p>{label ('empty')}</p>}
 
 	      <Pagination page={page} totalPages={totalPages}/>
 	    </div>)}

frontend/src/pages/tags/TagDetailPage.tsx

@@ -9,12 +9,13 @@ import FormField from '@/components/common/FormField'
 import PageTitle from '@/components/common/PageTitle'
 import MainArea from '@/components/layout/MainArea'
 import { toast } from '@/components/ui/use-toast'
-import { CATEGORIES, CATEGORY_NAMES } from '@/consts'
+import { CATEGORIES } from '@/consts'
 import { apiPut } from '@/lib/api'
 import { postsKeys, tagsKeys } from '@/lib/queryKeys'
 import { fetchTag } from '@/lib/tags'
 import { cn, inputClass } from '@/lib/utils'
 import { useValidationErrors } from '@/lib/useValidationErrors'
+import { useUITranslation } from '@/lib/useUITranslation'
 
 import type { FC, FormEvent } from 'react'
 
@@ -30,6 +31,7 @@ type TagFormField =
 
 const TagDetailPage: FC = () => {
   const locale = useLocale ()
+  const { message, label } = useUITranslation ('tags')
   const { id } = useParams ()
   const tagId = String (id ?? '')
   const tagKey = tagsKeys.show (tagId, locale)
@@ -72,12 +74,12 @@ const TagDetailPage: FC = () => {
 
       qc.invalidateQueries ({ queryKey: postsKeys.root })
       qc.invalidateQueries ({ queryKey: tagsKeys.root })
-      toast ({ description: '更新しました．' })
+      toast ({ description: label ('shared:messages.updated') })
     }
     catch (e)
     {
       applyValidationError (e)
-      toast ({ description: '更新に失敗しました．' })
+      toast ({ description: label ('shared:updateFailedMessage') })
     }
   }
 
@@ -98,7 +100,7 @@ const TagDetailPage: FC = () => {
 
   return (
       <MainArea>
-	{(loading || !(tag)) ? 'Loading...' : (
+	{(loading || !(tag)) ? label ('common:loading') : (
 	    <div className="max-w-xl">
 	      <PageTitle>
 		<TagLink
@@ -111,7 +113,7 @@ const TagDetailPage: FC = () => {
 		<FieldError messages={baseErrors}/>
 
 		{/* 名称 */}
-		<FormField label="名称" messages={fieldErrors.name}>
+		<FormField label={label ('history:name')} messages={fieldErrors.name}>
 		  {({ describedBy, invalid }) => (
 		      <>
 			{/* TODO: 補完に対応させる */}
@@ -127,7 +129,7 @@ const TagDetailPage: FC = () => {
 		</FormField>
 
 		{/* カテゴリ */}
-		<FormField label="カテゴリ" messages={fieldErrors.category}>
+		<FormField label={label ('common:categoryLabel')} messages={fieldErrors.category}>
 		  {({ describedBy, invalid }) => (
 		  <select
 		      disabled={disabled}
@@ -138,14 +140,15 @@ const TagDetailPage: FC = () => {
 		      className={inputClass (invalid)}>
 		    {CATEGORIES.filter (cat => tag.category === 'nico' || cat !== 'nico')
 			       .map (cat => (
-			<option key={cat} value={cat}>
+			<option key={cat} value={cat}
-			  {CATEGORY_NAMES[cat]}
+			    lang={message (`common:categories.${cat}`).language}>
+			  {message (`common:categories.${cat}`).text}
 			</option>))}
 		  </select>)}
 		</FormField>
 
 		{/* 別名 */}
-		<FormField label="別名" messages={fieldErrors.aliases}>
+		<FormField label={label ('aliases')} messages={fieldErrors.aliases}>
 		  {({ describedBy, invalid }) => (
 		      <>
 			{/* TODO: 補完に対応させる */}
@@ -161,7 +164,7 @@ const TagDetailPage: FC = () => {
 		</FormField>
 
 		{/* 上位タグ */}
-		<FormField label="上位タグ" messages={fieldErrors.parentTags}>
+		<FormField label={label ('parents')} messages={fieldErrors.parentTags}>
 		  {({ describedBy, invalid }) => (
 		      <>
 			{/* TODO: 補完に対応させる */}
@@ -176,7 +179,7 @@ const TagDetailPage: FC = () => {
 		      </>)}
 		</FormField>
 
-		<FormField label="廃止済" messages={fieldErrors.deprecated}>
+		<FormField label={label ('deprecated')} messages={fieldErrors.deprecated}>
 		  {({ describedBy, invalid }) => (
 		      <input
 			  type="checkbox"
@@ -195,7 +198,7 @@ const TagDetailPage: FC = () => {
 				     (disabled
 				      ? 'text-gray-300 bg-gray-500'
 				      : 'text-white bg-blue-500'))}>
-		    更新
+		    {label ('shared:actions.update')}
 		  </button>
 		</div>
 	      </form>

frontend/src/pages/wiki/WikiSearchPage.tsx

@@ -45,7 +45,7 @@ const WikiSearchPage: FC = () => {
 	</Helmet>
 
 	<div className="max-w-xl">
-	  <PageTitle>Wiki</PageTitle>
+	  <PageTitle>{label ('navigation:wiki')}</PageTitle>
 	  <form onSubmit={handleSearch} className="space-y-2">
 	    {/* タイトル */}
 	    <FormField label={label ('labels.title')}>