feat: expand YouTube playlists into individual queue tracks

_resolve_title replaced with _resolve_tracks using --flat-playlist to
enumerate playlist entries. cmd_play enqueues each track individually,
with truncation when the queue is nearly full. Single-video behavior
unchanged.

plugins/music.py

@@ -51,17 +51,33 @@ def _truncate(text: str, max_len: int = _MAX_TITLE_LEN) -> str:
     return text[: max_len - 3].rstrip() + "..."
 
 
-def _resolve_title(url: str) -> str:
-    """Resolve track title via yt-dlp. Blocking, run in executor."""
+def _resolve_tracks(url: str, max_tracks: int = _MAX_QUEUE) -> list[tuple[str, str]]:
+    """Resolve URL into (url, title) pairs via yt-dlp. Blocking, run in executor.
+
+    Handles both single videos and playlists. For playlists, returns up to
+    ``max_tracks`` individual entries. Falls back to ``[(url, url)]`` on error.
+    """
     try:
         result = subprocess.run(
-            ["yt-dlp", "--get-title", "--no-warnings", url],
-            capture_output=True, text=True, timeout=15,
+            [
+                "yt-dlp", "--flat-playlist", "--print", "url",
+                "--print", "title", "--no-warnings",
+                f"--playlist-end={max_tracks}", url,
+            ],
+            capture_output=True, text=True, timeout=30,
         )
-        title = result.stdout.strip()
-        return title if title else url
+        lines = result.stdout.strip().splitlines()
+        if len(lines) < 2:
+            return [(url, url)]
+        tracks = []
+        for i in range(0, len(lines) - 1, 2):
+            track_url = lines[i].strip()
+            track_title = lines[i + 1].strip()
+            if track_url:
+                tracks.append((track_url, track_title or track_url))
+        return tracks if tracks else [(url, url)]
     except Exception:
-        return url
+        return [(url, url)]
 
 
 # -- Play loop ---------------------------------------------------------------
@@ -110,12 +126,15 @@ def _ensure_loop(bot) -> None:
 # -- Commands ----------------------------------------------------------------
 
 
-@command("play", help="Music: !play <url>")
+@command("play", help="Music: !play <url|playlist>")
 async def cmd_play(bot, message):
     """Play a URL or add to queue if already playing.
 
     Usage:
         !play <url>     Play audio from URL (YouTube, SoundCloud, etc.)
+
+    Playlists are expanded into individual tracks. If the queue is nearly
+    full, only as many tracks as will fit are enqueued.
     """
     if not _is_mumble(bot):
         await bot.reply(message, "Music playback is Mumble-only")
@@ -133,20 +152,36 @@ async def cmd_play(bot, message):
         await bot.reply(message, f"Queue full ({_MAX_QUEUE} tracks)")
         return
 
+    remaining = _MAX_QUEUE - len(ps["queue"])
     loop = asyncio.get_running_loop()
-    title = await loop.run_in_executor(None, _resolve_title, url)
-    track = _Track(url=url, title=title, requester=message.nick or "?")
+    resolved = await loop.run_in_executor(None, _resolve_tracks, url, remaining)
 
-    ps["queue"].append(track)
+    was_idle = ps["current"] is None
+    requester = message.nick or "?"
+    added = 0
+    for track_url, track_title in resolved[:remaining]:
+        ps["queue"].append(_Track(url=track_url, title=track_title,
+                                  requester=requester))
+        added += 1
 
-    if ps["current"] is not None:
-        pos = len(ps["queue"])
+    total_resolved = len(resolved)
+
+    if added == 1:
+        title = _truncate(resolved[0][1])
+        if was_idle:
+            await bot.reply(message, f"Playing: {title}")
+        else:
+            pos = len(ps["queue"])
+            await bot.reply(message, f"Queued #{pos}: {title}")
+    elif added < total_resolved:
         await bot.reply(
             message,
-            f"Queued #{pos}: {_truncate(title)}",
+            f"Queued {added} of {total_resolved} tracks (queue full)",
         )
     else:
-        await bot.reply(message, f"Playing: {_truncate(title)}")
+        await bot.reply(message, f"Queued {added} tracks")
+
+    if was_idle:
         _ensure_loop(bot)