feat: i18n rss url and different excerpt length for different languages

src/utils/description.ts

@@ -1,14 +1,46 @@
 import type { CollectionEntry } from 'astro:content'
+import { defaultLocale } from '@/config'
 import MarkdownIt from 'markdown-it'
 import sanitizeHtml from 'sanitize-html'
 
 const parser = new MarkdownIt()
 
+type ExcerptScene = 'list' | 'meta' | 'og'
+
+// Excerpt length in different scenarios
+const EXCERPT_LENGTHS: Record<ExcerptScene, {
+  cjk: number
+  other: number
+}> = {
+  list: {
+    cjk: 120,
+    other: 240,
+  },
+  meta: {
+    cjk: 120,
+    other: 240,
+  },
+  og: {
+    cjk: 75,
+    other: 150,
+  },
+}
+
+const isCJKLang = (lang: string) => ['zh', 'zh-tw', 'ja'].includes(lang)
+
 // Generate an excerpt from Markdown content
-export function generateExcerpt(content: string, length: number = 98): string {
+export function generateExcerpt(
+  content: string,
+  scene: ExcerptScene,
+  lang: string,
+): string {
   if (!content)
     return ''
 
+  const length = isCJKLang(lang)
+    ? EXCERPT_LENGTHS[scene].cjk
+    : EXCERPT_LENGTHS[scene].other
+
   // Convert Markdown to plain text
   const plainText = sanitizeHtml(parser.render(content), {
     allowedTags: [],
@@ -23,11 +55,14 @@ export function generateExcerpt(content: string, length: number = 98): string {
 }
 
 // Automatically generate a description for the article
-export function generateDescription(post: CollectionEntry<'posts'>): string {
+export function generateDescription(
+  post: CollectionEntry<'posts'>,
+  scene: ExcerptScene,
+): string {
   // If the article already has a description, return it directly
   if (post.data.description)
     return post.data.description
 
-  // Otherwise, generate an excerpt from the article content as the description
-  return generateExcerpt(post.body)
+  const lang = post.data.lang ?? defaultLocale
+  return generateExcerpt(post.body, scene, lang)
 }