アイヌ語追加 (#428) (#433)

Reviewed-on: #433
Co-authored-by: miteruzo <miteruzo@naver.com>

frontend/src/components/LocalisedText.tsx

@@ -0,0 +1,89 @@
+import { Children, cloneElement, Fragment, isValidElement } from 'react'
+
+import { cn } from '@/lib/utils'
+
+import type { ReactNode } from 'react'
+
+
+export const formatUIString = (text: string, language: string): string =>
+    (language === 'ain' || language === 'ain-Kana')
+    ? text.replace (/[ \t\r\n]+/g, '\u3000')
+    : text
+
+
+const splitAinuText = (text: string): string[] => {
+  const parts: string[] = []
+  let part = ''
+  let boundary = false
+  for (const character of text)
+  {
+    // Keep punctuation runs and closing brackets/quotes with the preceding word.
+    if (boundary && !/[\u3000、，,。．\p{Pe}\p{Pf}]/u.test (character))
+    {
+      parts.push (part)
+      part = ''
+      boundary = false
+    }
+    part += character
+    if (/[\u3000、，,。．]/u.test (character))
+      boundary = true
+  }
+  if (part !== '')
+    parts.push (part)
+  return parts
+}
+
+
+export const localiseUIChildren = (children: ReactNode, language: string): ReactNode => {
+  if (language !== 'ain' && language !== 'ain-Kana')
+    return children
+
+  return Children.map (children, child => {
+    if (typeof child === 'string')
+    {
+      const parts = splitAinuText (formatUIString (child, language))
+      return parts.map ((part, index) => {
+	const spaces = part.match (/\u3000+$/u)?.[0] ?? ''
+	const word = part.slice (0, part.length - spaces.length)
+	return (
+	    <Fragment key={index}>
+	      {word !== '' && <span className="ainu-ui-word">{word}</span>}
+	      {spaces}
+	      {index < parts.length - 1 && <wbr/>}
+	    </Fragment>)
+      })
+    }
+
+    if (isValidElement<{ children?: ReactNode; lang?: string }> (child))
+    {
+      // Only traverse inline formatting owned by the renderer. Components,
+      // links and code retain their own children and behaviour.
+      const inline = child.type === Fragment
+	  || (typeof child.type === 'string'
+	      && ['span', 'em', 'strong', 'del', 's', 'b', 'i', 'u',
+		  'small', 'mark', 'sup', 'sub'].includes (child.type))
+      if (!inline
+	  || (child.props.lang != null && !(child.props.lang.startsWith ('ain'))))
+	return child
+      return cloneElement (child, { }, localiseUIChildren (child.props.children, language))
+    }
+
+    return child
+  })
+}
+
+
+const LocalisedText = (
+    { children, language, className }: {
+	children: ReactNode
+	language: string
+	className?: string },
+) => (
+    <span lang={language === 'ain' ? 'ain-Kana' : language}
+	className={cn ((language === 'ain' || language === 'ain-Kana') && 'ainu-ui-text',
+		      className)}>
+      {localiseUIChildren (children, language)}
+    </span>)
+
+
+export default LocalisedText