correction to hashtag handling

src/lib/mastodon.ts

@@ -18,16 +18,15 @@ function extractMaxId(linkHeader: string | null): string | null {
 }
 
 /**
- * Extracts hashtag names from Mastodon HTML content as a supplement to post.tags.
+ * Extracts hashtag names from Mastodon HTML content with original casing preserved.
  * Mastodon renders hashtags as: #<span>TagName</span> inside an anchor.
  */
 function extractTagsFromHtml(html: string): string[] {
   const results: string[] = []
-  // Match: #<span>TagName</span>
   const re = /#<span>([^<]+)<\/span>/gi
   let m: RegExpExecArray | null
   while ((m = re.exec(html)) !== null) {
-    results.push(m[1].toLowerCase())
+    results.push(m[1]) // preserve original casing
   }
   return results
 }
@@ -36,7 +35,7 @@ async function fetchPage(tag: string, maxId?: string): Promise<TimelineResult> {
   const instance = process.env.MASTODON_INSTANCE
   if (!instance) throw new Error('MASTODON_INSTANCE is not configured')
 
-  let url = `${instance}/api/v1/timelines/tag/${encodeURIComponent(tag)}?limit=40`
+  let url = `${instance}/api/v1/timelines/tag/${encodeURIComponent(tag)}`
   if (maxId) url += `&max_id=${maxId}`
 
   const headers: HeadersInit = { Accept: 'application/json' }
@@ -123,15 +122,12 @@ export async function getPostsData(
     postsPerHour = allPosts.length / (coveredMs / ONE_HOUR_MS)
   }
 
-  // Count co-occurring tags — merge post.tags with tags parsed from HTML content
+  // Count co-occurring tags from the API tags object (authoritative for membership)
   const counts = new Map<string, number>()
   const lowerTag = tag.toLowerCase()
   for (const post of allPosts) {
-    const fromApi = (post.tags ?? []).map((t) => t.name.toLowerCase())
-    const fromContent = extractTagsFromHtml(post.content)
-    // Union of both sources
-    const allTagNames = [...new Set([...fromApi, ...fromContent])]
-    for (const name of allTagNames) {
+    for (const t of post.tags ?? []) {
+      const name = t.name.toLowerCase()
       if (name !== lowerTag && name.length >= 2 && name.length <= 100) {
         counts.set(name, (counts.get(name) ?? 0) + 1)
       }
@@ -143,14 +139,22 @@ export async function getPostsData(
     .slice(0, 10)
     .map(([name]) => name)
 
-  // Derive the most common casing variant for the queried tag itself
+  // Derive the most common casing variant for the queried tag itself.
+  // Merges post.tags (e.g. "JavaScript") with HTML-rendered span variants for better coverage.
   const casingCounts = new Map<string, number>()
   for (const post of allPosts) {
+    // From API tags array
     for (const t of post.tags ?? []) {
       if (t.name.toLowerCase() === lowerTag) {
         casingCounts.set(t.name, (casingCounts.get(t.name) ?? 0) + 1)
       }
     }
+    // From HTML content (preserves original casing as typed by the user)
+    for (const variant of extractTagsFromHtml(post.content)) {
+      if (variant.toLowerCase() === lowerTag) {
+        casingCounts.set(variant, (casingCounts.get(variant) ?? 0) + 1)
+      }
+    }
   }
   let displayTag: string | undefined
   if (casingCounts.size > 0) {