#428

frontend/src/lib/locales.ts

@@ -35,6 +35,17 @@ export const localeFromPath = (pathname: string): LocaleCode | null => {
 }
 
 
+export const resolveViewingLocale = (
+    pathname: string,
+    routeLocale?: unknown,
+): LocaleCode =>
+    isLocaleCode (routeLocale) ? routeLocale : localeFromPath (pathname) ?? 'ja'
+
+
+export const currentViewingLocale = (): LocaleCode =>
+    resolveViewingLocale (typeof window === 'undefined' ? '' : window.location.pathname)
+
+
 export const unlocalisedPath = (pathname: string): string => {
   const locale = localeFromPath (pathname)
   return locale == null ? pathname : pathname.slice (locale.length + 1) || '/'

frontend/src/lib/prefetchers.ts

@@ -118,8 +118,9 @@ const prefetchWikiPageShow: Prefetcher = async (qc, url, locale) => {
 
   if (wikiPage?.body)
   {
-    const language = wikiPage.languageCode
+    const contentLanguage = wikiPage.languageCode
 	?? (wikiPage.resourceType === 'tag_description' ? localeLanguage (locale) : 'und')
+    const language = contentLanguage === 'und' ? 'ja' : contentLanguage
     await qc.prefetchQuery ({
 	queryKey: wikiKeys.autolinkCandidates (language, locale),
 	queryFn: () => fetchWikiAutolinkCandidates (language, locale) })

frontend/src/lib/queryKeys.ts

@@ -60,11 +60,11 @@ export const tagsKeys = {
     nicoIndex:    (
     p: FetchNicoTagsParams,
     locale: LocaleCode = 'ja',
-) => ['tags', locale, 'nico', 'index', p] as const,
+) => ['tags', 'nico', locale, 'index', p] as const,
     externalShow: (
     id: string,
     locale: LocaleCode = 'ja',
-) => ['tags', locale, 'nico', id] as const,
+) => ['tags', 'nico', locale, id] as const,
     show:         (
     name: string,
     locale: LocaleCode = 'ja',

frontend/src/lib/remark-wiki-autolink.ts

@@ -1,6 +1,7 @@
 import type { Content, Parent, Root, RootContent } from 'mdast'
 
 import type { WikiAutolinkCandidate } from '@/types'
+import type { LocaleCode } from '@/lib/locales'
 
 const escapeForRegExp = (s: string) => s.replace (/[.*+?^${}()|[\]\\]/g, '\\$&')
 
@@ -34,12 +35,14 @@ const edgeCharacter = (node: Content, first: boolean): string => {
 const remarkWikiAutoLink = (
     candidates: WikiAutolinkCandidate[],
     language: string,
+    locale: LocaleCode,
 ): ((tree: Root) => void) => {
   const targets = new Map<string, WikiAutolinkCandidate> ()
   const ambiguous = new Set<string> ()
   for (const candidate of candidates)
   {
-    if (candidate.languageCode !== language || candidate.name.length === 0)
+    if (candidate.languageCode !== language || candidate.localeCode !== locale
+	|| candidate.name.length === 0)
       continue
     const previous = targets.get (candidate.name)
     if (previous != null
@@ -89,7 +92,7 @@ const remarkWikiAutoLink = (
 	    parts.push ({ type: 'text', value: value.slice (last, start) })
 	  parts.push ({
 	      type: 'link',
-	      url: `/${candidate.localeCode}/wiki/${encodeURIComponent (candidate.resourceId)}`,
+	      url: `/${locale}/wiki/${encodeURIComponent (candidate.resourceId)}`,
 	      title: null,
 	      children: [{ type: 'text', value: match[0] }],
 	      data: { hProperties: { 'data-wiki': '1' } } })

frontend/src/lib/useLocale.ts

@@ -1,7 +1,7 @@
 import { useCallback } from 'react'
 import { useLocation, useNavigate, useParams } from 'react-router-dom'
 
-import { isLocaleCode, localeFromPath, localiseTo } from '@/lib/locales'
+import { localiseTo, resolveViewingLocale } from '@/lib/locales'
 
 import type { NavigateFunction, NavigateOptions, To } from 'react-router-dom'
 
@@ -11,7 +11,7 @@ import type { LocaleCode } from '@/lib/locales'
 export const useLocale = (): LocaleCode => {
   const { locale } = useParams ()
   const location = useLocation ()
-  return isLocaleCode (locale) ? locale : localeFromPath (location.pathname) ?? 'ja'
+  return resolveViewingLocale (location.pathname, locale)
 }
 
 

frontend/src/lib/utils.ts

@@ -2,6 +2,7 @@ import { clsx } from 'clsx'
 import { twMerge } from 'tailwind-merge'
 
 import { i18n } from '@/lib/i18n'
+import { currentViewingLocale } from '@/lib/locales'
 
 import type { ClassValue } from 'clsx'
 
@@ -14,37 +15,39 @@ export const toDate = (d: string | Date): Date => typeof d === 'string' ? new Da
 export const cn = (...inputs: ClassValue[]) => twMerge (clsx (...inputs))
 
 
-export const dateString = (
-    d:        string | Date,
-    unknown:  'month' | 'day' | 'hour' | 'minute' | 'second' | null = null): string =>
-    toDate (d).toLocaleString (
-	'ja-JP-u-ca-japanese',
-	{ era: 'long',
-	  year: 'numeric',
-	  month: (unknown === 'month' ? undefined : 'long'),
+type DatePrecision = 'month' | 'day' | 'hour' | 'minute' | 'second' | null
+
+const dateFormatters = new Map<DatePrecision, Intl.DateTimeFormat> ()
+let ainuDateFormatter: Intl.DateTimeFormat | null = null
+
+
+const formatDateString = (
+    date: Date,
+    unknown: DatePrecision,
+    locale: LocaleCode,
+): string => {
+  if (Number.isNaN (date.getTime ()))
+    return date.toString ()
+  if (locale === 'ja')
+  {
+    if (!dateFormatters.has (unknown))
+    {
+      dateFormatters.set (unknown, new Intl.DateTimeFormat ('ja-JP-u-ca-japanese', {
+	  era: 'long', year: 'numeric',
+	  month: unknown === 'month' ? undefined : 'long',
 	  day: unknown != null && ['month', 'day'].includes (unknown) ? undefined : 'numeric',
 	  weekday: unknown != null && ['month', 'day'].includes (unknown) ? undefined : 'short',
 	  hour: unknown == null || ['second', 'minute'].includes (unknown) ? 'numeric' : undefined,
 	  minute: unknown == null || unknown === 'second' ? 'numeric' : undefined,
-	  second: unknown == null ? 'numeric' : undefined })
-
-
-export const localisedDateString = (
-    value: string | Date,
-    locale: LocaleCode,
-    unknown: Parameters<typeof dateString>[1] = null,
-): string => {
-  if (locale === 'ja')
-    return dateString (value, unknown)
-
-  const date = toDate (value)
-  if (Number.isNaN (date.getTime ()))
-    return dateString (value, unknown)
-
-  const parts = new Intl.DateTimeFormat ('en-CA', {
+	  second: unknown == null ? 'numeric' : undefined }))
+    }
+    return dateFormatters.get (unknown)!.format (date)
+  }
+  ainuDateFormatter ??= new Intl.DateTimeFormat ('en-CA', {
       year: 'numeric', month: '2-digit', day: '2-digit',
       hour: '2-digit', minute: '2-digit', second: '2-digit',
-      hourCycle: 'h23' }).formatToParts (date)
+      hourCycle: 'h23' })
+  const parts = ainuDateFormatter.formatToParts (date)
   const part = (type: string) => parts.find (entry => entry.type === type)?.value ?? ''
   const omitDay = unknown != null && ['month', 'day'].includes (unknown)
   const dateParts = [part ('year'),
@@ -60,6 +63,20 @@ export const localisedDateString = (
 }
 
 
+export const dateString = (
+    value: string | Date,
+    unknown: DatePrecision = null,
+    locale?: LocaleCode,
+): string => formatDateString (toDate (value), unknown, locale ?? currentViewingLocale ())
+
+
+export const localisedDateString = (
+    value: string | Date,
+    locale: LocaleCode,
+    unknown: DatePrecision = null,
+): string => dateString (value, unknown, locale)
+
+
 export const originalCreatedAtString = (
     f:  string | Date | null,
     b:  string | Date | null,