#428

frontend/src/App.tsx

@@ -1,6 +1,6 @@
 import { useQuery } from '@tanstack/react-query'
 import { AnimatePresence, LayoutGroup, MotionConfig, motion } from 'framer-motion'
-import { Fragment, useEffect, useLayoutEffect, useMemo, useState } from 'react'
+import { Fragment, Suspense, lazy, useEffect, useLayoutEffect, useMemo, useState } from 'react'
 import { useTranslation } from 'react-i18next'
 import { createBrowserRouter,
 	 Navigate,
@@ -40,7 +40,7 @@ import MaterialListPage from '@/pages/materials/MaterialListPage'
 import MaterialNewPage from '@/pages/materials/MaterialNewPage'
 import MaterialSyncSuppressionsPage from '@/pages/materials/MaterialSyncSuppressionsPage'
 import MorePage from '@/pages/MorePage'
-import GekanatorPage from '@/pages/GekanatorPage'
+import GekanatorUnavailablePage from '@/pages/GekanatorUnavailablePage'
 import NicoTagListPage from '@/pages/tags/NicoTagListPage'
 import NotFound from '@/pages/NotFound'
 import TOSPage from '@/pages/TOSPage'
@@ -72,6 +72,23 @@ import type { ClientAnimationMode } from '@/lib/settings'
 import type { AvailableLocale } from '@/lib/locales'
 import type { User } from '@/types'
 
+const GekanatorPage = lazy (() => import ('@/pages/GekanatorPage'))
+
+
+const GekanatorRoute = ({ user }: { user: User | null }) => {
+  const locale = useLocale ()
+  const location = useLocation ()
+  const pageLocale = requiredPageLocale (location.pathname)
+
+  if (pageLocale != null && pageLocale !== locale)
+    return <GekanatorUnavailablePage/>
+
+  return (
+      <Suspense fallback={null}>
+	<GekanatorPage user={user}/>
+      </Suspense>)
+}
+
 
 const RouteTransitionWrapper = ({ animationMode, user, setUser }: {
     animationMode:  ClientAnimationMode
@@ -114,7 +131,7 @@ const RouteTransitionWrapper = ({ animationMode, user, setUser }: {
 	<Route path="users/settings" element={<SettingPage user={user} setUser={setUser}/>}/>
 	<Route path="settings" element={<LocaleRedirect to="/users/settings"/>}/>
 	<Route path="tos" element={<TOSPage/>}/>
-	<Route path="gekanator" element={<GekanatorPage user={user}/>}/>
+	<Route path="gekanator" element={<GekanatorRoute user={user}/>}/>
 	<Route path="more" element={<MorePage/>}/>
 	<Route path="*" element={<NotFound/>}/>
       </Routes>)
@@ -278,11 +295,9 @@ const LocaleRoute: FC = () => {
       refetchOnMount: 'always',
       refetchOnWindowFocus: 'always',
       refetchOnReconnect: 'always' })
-  const pageLocale = requiredPageLocale (location.pathname)
   const activeLocale =
       (isLocaleCode (locale)
-       && data?.locales.some (entry => entry.code === locale)
+       && data?.locales.some (entry => entry.code === locale))
-       && (pageLocale == null || pageLocale === locale))
       ? locale
       : null
 
@@ -304,12 +319,6 @@ const LocaleRoute: FC = () => {
     return <ServiceUnavailable/>
   if (isPending)
     return null
-  if (pageLocale != null && isLocaleCode (locale) && pageLocale !== locale)
-  {
-    return data.locales.some (entry => entry.code === pageLocale)
-	? <Navigate to={switchLocalePath (location, pageLocale)} replace/>
-	: <NotFound/>
-  }
   if (isLocaleCode (locale))
   {
     return data.locales.some (entry => entry.code === locale)

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

@@ -0,0 +1,8 @@
+{
+  "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"
+  }
+}

frontend/src/locales/ja/gekanator.json

@@ -0,0 +1,8 @@
+{
+  "unavailable": {
+    "title": "グカネータは現在日本語のみでプレー可能です！",
+    "back": "前の画面に戻る",
+    "switchToJapanese": "日本語に切替へる",
+    "imageAlt": "号泣している洗澡鹿"
+  }
+}

frontend/src/pages/GekanatorUnavailablePage.tsx

@@ -0,0 +1,143 @@
+import { motion, useReducedMotion } from 'framer-motion'
+import { useLayoutEffect, useRef } from 'react'
+import { Helmet } from 'react-helmet-async'
+import { useLocation } from 'react-router-dom'
+
+import nikumaru from '@/assets/fonts/nikumaru.otf'
+import { formatUIString } from '@/components/LocalisedText'
+import PrefetchLink from '@/components/PrefetchLink'
+import MainArea from '@/components/layout/MainArea'
+import { Button } from '@/components/ui/button'
+import { SITE_TITLE } from '@/config'
+import { switchLocalePath } from '@/lib/locales'
+import { useClientBehaviourSettings } from '@/lib/useClientBehaviourSettings'
+import { useLocaleNavigate } from '@/lib/useLocale'
+import { useUITranslation } from '@/lib/useUITranslation'
+
+
+const GekanatorUnavailablePage = () => {
+  const location = useLocation ()
+  const navigate = useLocaleNavigate ()
+  const behaviourSettings = useClientBehaviourSettings ()
+  const prefersReducedMotion = useReducedMotion ()
+  const shakeMascot = (behaviourSettings.animation ?? 'normal') === 'normal'
+      && !prefersReducedMotion
+  const { message, label } = useUITranslation ('gekanator')
+  const title = message ('unavailable.title')
+  const imageAlt = message ('unavailable.imageAlt')
+  const headingRef = useRef<HTMLHeadingElement> (null)
+
+  useLayoutEffect (() => {
+    const heading = headingRef.current
+    const context = document.createElement ('canvas').getContext ('2d')
+    if (heading == null || context == null)
+      return
+
+    const fitTitle = () => {
+      heading.style.fontSize = ''
+      heading.style.maxWidth = ''
+      const style = window.getComputedStyle (heading)
+      const minimum = Number.parseFloat (style.fontSize)
+      context.font = `${style.fontWeight} ${minimum}px ${style.fontFamily}`
+      const width = context.measureText (formatUIString (title.text, title.language)).width
+      if (width > 0)
+      {
+	const available = heading.clientWidth
+	const fitted = minimum * Math.max (0, available - 1) / width
+	const fontSize = Math.max (minimum, fitted)
+	heading.style.fontSize = `${fontSize}px`
+	let lower = available / 2
+	let upper = available
+	// Keep the one-line font size and find a width that allows two lines.
+	for (let step = 0; step < 12; ++step)
+	{
+	  const candidate = (lower + upper) / 2
+	  heading.style.maxWidth = `${candidate}px`
+	  if (heading.scrollHeight <= fontSize * 1.25 * 2 + 1
+	      && heading.scrollWidth <= heading.clientWidth)
+	    upper = candidate
+	  else
+	    lower = candidate
+	}
+	heading.style.maxWidth = `${Math.ceil (upper)}px`
+      }
+    }
+
+    let disposed = false
+    const resizeObserver = new ResizeObserver (fitTitle)
+    resizeObserver.observe (heading)
+    window.addEventListener ('resize', fitTitle)
+    document.fonts.addEventListener ('loadingdone', fitTitle)
+    void document.fonts.ready.then (() => {
+      if (!disposed)
+	fitTitle ()
+    })
+    fitTitle ()
+
+    return () => {
+      disposed = true
+      resizeObserver.disconnect ()
+      window.removeEventListener ('resize', fitTitle)
+      document.fonts.removeEventListener ('loadingdone', fitTitle)
+    }
+  }, [title.text, title.language])
+
+  const goBack = () => {
+    // The router index excludes unrelated external history and is zero on direct entry.
+    const index: unknown = window.history.state?.idx
+    if (typeof index === 'number' && index > 0)
+      navigate (-1)
+    else
+      navigate ('/posts', { replace: true })
+  }
+
+  return (
+      <MainArea className="min-w-0">
+	<Helmet>
+	  <title>{title.text} | {SITE_TITLE}</title>
+	  <meta name="robots" content="noindex"/>
+	  <style>{`
+	      @font-face {
+		font-family: 'Nikumaru';
+		src: url(${nikumaru}) format('opentype');
+	      }
+	  `}</style>
+	</Helmet>
+	<section className="mx-auto flex min-h-full w-full flex-col
+			    items-center justify-center gap-6 py-6 text-center">
+	  <h1 ref={headingRef} className="w-full text-5xl font-bold"
+	      style={{ fontFamily: 'Nikumaru', lineHeight: 1.25 }}>
+	    {label ('unavailable.title')}
+	  </h1>
+	  <motion.img
+	      src="/assets/gekanator/mascot-failed.png"
+	      alt={imageAlt.text}
+	      lang={imageAlt.language}
+	      width={1179}
+	      height={1179}
+	      animate={shakeMascot
+		  ? { x: [0, -10, 10, -8, 8, 0], y: [0, 8, -8, 10, -10, 0], rotate: 0 }
+		  : { x: 0, y: 0, rotate: 0 }}
+	      transition={{ duration: shakeMascot ? .16 : 0,
+		  repeat: shakeMascot ? Infinity : 0, ease: 'linear' }}
+	      className="h-auto max-h-[50dvh] w-full max-w-lg object-contain"/>
+	  <div className="flex w-full flex-col items-stretch justify-center gap-3 md:flex-row">
+	    <Button
+		type="button"
+		variant="outline"
+		onClick={goBack}
+		className="h-auto min-h-10 min-w-0 whitespace-normal">
+	      {label ('unavailable.back')}
+	    </Button>
+	    <Button asChild className="h-auto min-h-10 min-w-0 whitespace-normal">
+	      <PrefetchLink to={switchLocalePath (location, 'ja')}>
+		{label ('unavailable.switchToJapanese')}
+	      </PrefetchLink>
+	    </Button>
+	  </div>
+	</section>
+      </MainArea>)
+}
+
+
+export default GekanatorUnavailablePage