Do not offer a player for a file that is not audio or video

The media-type filter stopped new image enclosures being fetched, but ones
already on disk still got a play button and an <audio> element, because
the UI tested for a path rather than for a playable type. Four places did
this, including play() itself, which picked the first downloaded enclosure
whatever it was.

isPlayable() checks audio/* or video/*, falling back to the extension when
a feed declares no type. A downloaded non-media file now shows as its kind
with Save and Delete, so it stays available without posing as an episode.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AdXho5tTkjFLeUXKbEjKBh

web/index.html

@@ -619,6 +619,7 @@ function renderEntries(){
 function epEl(e){
   const enc=e.enclosures[0];
   const has=!!(enc&&enc.path);
+  const playable=isPlayable(enc);
   const el=document.createElement('div');
   el.className='ep'+(e.read?' read':'')+(S.sel===e.guid?' sel':'')+
     (player.guid===e.guid?' playing':'');
@@ -643,8 +644,8 @@ function epEl(e){
       ${enc&&enc.last_error?`<div class="line" style="color:var(--bad)">${esc(enc.last_error)}</div>`:''}
     </div>
     <div class="rowacts">
-      ${has?`<button class="iconbtn" data-a="play" title="Play">▶</button>`:
-            (enc?`<button class="iconbtn" data-a="get" title="Download this ${
+      ${playable?`<button class="iconbtn" data-a="play" title="Play">▶</button>`:
+            (enc&&!has?`<button class="iconbtn" data-a="get" title="Download this ${
               enc.state==='skipped'?kindOf(enc):'file'}">⤓</button>`:'')}
       <button class="iconbtn" data-a="flag" title="${e.flagged?'Stop keeping':'Keep (never auto-delete)'}">${e.flagged?'★':'☆'}</button>
       <button class="iconbtn" data-a="read" title="Mark ${e.read?'unread':'read'}">${e.read?'○':'●'}</button>
@@ -652,7 +653,7 @@ function epEl(e){
     </div>`;
 
   const art=$('.art',el);
-  if(art&&has){
+  if(art&&playable){
     art.insertAdjacentHTML('beforeend','<span class="ovl">▶</span>');
     art.onclick=ev=>{ ev.stopPropagation(); play(e); };
   }
@@ -660,6 +661,19 @@ function epEl(e){
   $$('.rowacts .iconbtn',el).forEach(b=>b.onclick=ev=>{ev.stopPropagation();epAction(b.dataset.a,e,el)});
   return el;
 }
+/// Whether the browser can play it. Having a file is not the same as being playable:
+/// blog feeds put article images in enclosures, and an <audio> element pointed at a JPEG
+/// is just a broken player.
+function isPlayable(x){
+  if(!x || !x.path) return false;
+  const m=(x.mime||'').toLowerCase();
+  if(m.startsWith('audio/')||m.startsWith('video/')) return true;
+  if(m) return false;
+  // No declared type: fall back to the file's extension.
+  return /\.(mp3|m4a|m4b|aac|ogg|oga|opus|flac|wav|mp4|m4v|mov|webm|mkv)$/i
+    .test((x.path||x.url||'').split('?')[0]);
+}
+
 /// What an enclosure is, for a row that is not an episode: "image", "pdf", "document".
 function kindOf(enc){
   const m=(enc.mime||'').toLowerCase();
@@ -736,6 +750,15 @@ function showDetail(e){
 /// One enclosure: a player when the file is here, otherwise what it is and a way to get it.
 function encBox(x){
   const size=x.length?mb(x.length):'';
+  if(x.path && !isPlayable(x)){
+    // On disk, but not audio or video: offer the file, not a player.
+    return `<div class="encbox">
+      <span class="chip done">${esc(kindOf(x))}</span>
+      <span class="meta" style="flex:1">downloaded${size?' \u00b7 '+size:''}</span>
+      <a class="btn" href="/media/${x.id}" download>Save</a>
+      <button class="btn danger" data-a="del" data-enc="${x.id}">Delete file</button>
+    </div>`;
+  }
   if(x.path){
     return `<div class="encbox">
       <audio id="audio-${x.id}" controls preload="none" src="/media/${x.id}"></audio>
@@ -793,8 +816,11 @@ function markPlayed(){
 }
 
 function play(e){
-  const enc=e.enclosures.find(x=>x.path);
-  if(!enc){ toast('Not downloaded yet',true); return; }
+  const enc=e.enclosures.find(isPlayable);
+  if(!enc){
+    toast(e.enclosures.some(x=>x.path) ? 'That file is not audio or video' : 'Not downloaded yet', true);
+    return;
+  }
   const resuming = player.guid===e.guid;
   if(!resuming){
     player.guid=e.guid; player.feed=e.feed_id; player.entry=e;