v1.18.0 (#815)

Co-authored-by: Artur Tamazian <artur-tamazian>
Co-authored-by: Javier Gonzalez <javierggt@yahoo.com>

katrain/gui/sound.py

@@ -1,9 +1,9 @@
 from kivy.clock import Clock
-from kivymd.app import MDApp
 from kivy.core.audio import SoundLoader
 from kivy.utils import platform
 
 cached_sounds = {}
+_audio_available = False
 
 # prefer ffpyplayer on linux, then others, avoid gst and avoid or ffpyplayer on windows
 ranking = [("ffplay", 98 if platform in ["win", "macosx"] else -2), ("sdl", -1), ("gst", 99), ("", 0)]
@@ -13,22 +13,56 @@ except Exception as e:
     print("Exception sorting sound loaders: ", e)  # private vars, so could break with versions etc
 
 
-def play_sound(file, volume=1, cache=True):
-    def _play(sound):
-        if sound:
-            sound.play()
-            sound.seek(0)
+def preload_sounds(sound_dir):
+    """Preload all sounds before the SDL2 window is created.
 
+    SoundLoader.load() deadlocks when no audio output device is available,
+    so we test audio in a subprocess first.
+    """
+    global _audio_available
+    import os
+    import sys
+    import subprocess
+
+    audio_files = [
+        os.path.join(sound_dir, fn) for fn in os.listdir(sound_dir)
+        if fn.endswith((".wav", ".ogg", ".mp3"))
+    ]
+    if not audio_files:
+        return
+
+    # Test if audio subsystem works by loading one sound in a subprocess
+    try:
+        subprocess.run(
+            [sys.executable, "-c",
+             f"from kivy.core.audio import SoundLoader; SoundLoader.load({audio_files[0]!r})"],
+            timeout=3, capture_output=True,
+        )
+    except subprocess.TimeoutExpired as e:
+        print(f"Warning: Audio unavailable ({e}). Sounds disabled.", file=sys.stderr)
+        return
+
+    # Audio works, preload all sounds
+    for path in audio_files:
+        cached_sounds[os.path.basename(path)] = SoundLoader.load(path)
+    _audio_available = True
+
+
+def play_sound(file, volume=1, cache=True):
+    if not _audio_available:
+        return
+
+    # the following import causes the creation of an SDL2 window, and if there
+    # is no sound device, it deadlocks. We delay the import until we know audio
+    # is available
+    from kivymd.app import MDApp
     app = MDApp.get_running_app()
     if app and app.gui and app.gui.config("timer/sound"):
         sound = cached_sounds.get(file)
-        if sound is None:
-            sound = SoundLoader.load(file)
-            if cache:
-                cached_sounds[file] = sound
         if sound is not None:
             sound.volume = volume
-            Clock.schedule_once(lambda _dt: _play(sound), 0)
+            sound.play()
+            sound.seek(0)
 
 
 def stop_sound(file):