feat: automatically generate meta descriptions for articles

src/utils/description.ts

@@ -0,0 +1,34 @@
+import type { CollectionEntry } from 'astro:content'
+import MarkdownIt from 'markdown-it'
+import sanitizeHtml from 'sanitize-html'
+
+const parser = new MarkdownIt()
+
+// Generate an excerpt from Markdown content
+export function generateExcerpt(content: string, length: number = 100): string {
+  if (!content)
+    return ''
+
+  // Convert Markdown to plain text
+  const plainText = sanitizeHtml(parser.render(content), {
+    allowedTags: [],
+    allowedAttributes: {},
+  })
+
+  // Replace line breaks with spaces
+  const normalizedText = plainText.replace(/\s+/g, ' ')
+  const excerpt = normalizedText.slice(0, length).trim()
+  // Add ellipsis if text was truncated
+  const needsEllipsis = normalizedText.length > length
+  return needsEllipsis ? `${excerpt}...` : excerpt
+}
+
+// Automatically generate a description for the article
+export function generateDescription(post: CollectionEntry<'posts'>): 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)
+}