Add looping gameplay music

engine/sdl2.py

@@ -5,6 +5,10 @@ from ctypes import *
 
 import sdl2
 import sdl2.ext
+try:
+    import sdl2.sdlmixer as sdlmixer
+except ImportError:
+    sdlmixer = None
 from sdl2.ext.compat import byteify
 from sdl2 import SDL_AudioSpec
 from PIL import Image
@@ -124,6 +128,73 @@ class GameWindow:
         self.audio_devs["base"] = sdl2.SDL_OpenAudioDevice(None, 0, audio_spec, None, 0)
         self.audio_devs["effects"] = sdl2.SDL_OpenAudioDevice(None, 0, audio_spec, None, 0)
         self.audio_devs["music"] = sdl2.SDL_OpenAudioDevice(None, 0, audio_spec, None, 0)
+        self.music_enabled = False
+        self.music_volume = 128
+        self.music_track = None
+        self.music_path = None
+
+        if sdlmixer is None:
+            return
+
+        mixer_flags = getattr(sdlmixer, "MIX_INIT_MP3", 0)
+        init_result = sdlmixer.Mix_Init(mixer_flags)
+        if mixer_flags and init_result & mixer_flags != mixer_flags:
+            print("[audio] SDL_mixer MP3 support not available")
+            return
+
+        if sdlmixer.Mix_OpenAudio(44100, sdl2.AUDIO_S16SYS, sdlmixer.MIX_DEFAULT_CHANNELS, 2048) != 0:
+            print(f"[audio] failed to open music mixer: {sdl2.SDL_GetError()}")
+            return
+
+        self.music_enabled = True
+        sdlmixer.Mix_VolumeMusic(self.music_volume)
+
+    def set_volume(self, volume_percent):
+        clamped = max(0, min(int(volume_percent), 100))
+        self.music_volume = int(round(clamped * 128 / 100))
+        if self.music_enabled and sdlmixer is not None:
+            sdlmixer.Mix_VolumeMusic(self.music_volume)
+
+    def play_music(self, music_file, loop=True):
+        if not self.audio or not self.music_enabled or sdlmixer is None:
+            return False
+
+        music_path = str(resolve_bundle_path(os.path.join("assets", "music", music_file)))
+        if self.music_path != music_path:
+            self._free_music_track()
+            self.music_track = sdlmixer.Mix_LoadMUS(byteify(music_path, "utf-8"))
+            if not self.music_track:
+                print(f"[audio] failed to load music: {music_path}")
+                return False
+            self.music_path = music_path
+
+        if sdlmixer.Mix_PausedMusic():
+            sdlmixer.Mix_ResumeMusic()
+            return True
+
+        if sdlmixer.Mix_PlayingMusic():
+            return True
+
+        loops = -1 if loop else 0
+        if sdlmixer.Mix_PlayMusic(self.music_track, loops) != 0:
+            print(f"[audio] failed to play music: {music_path}")
+            return False
+        return True
+
+    def pause_music(self):
+        if self.music_enabled and sdlmixer is not None and sdlmixer.Mix_PlayingMusic() and not sdlmixer.Mix_PausedMusic():
+            sdlmixer.Mix_PauseMusic()
+
+    def stop_music(self):
+        if self.music_enabled and sdlmixer is not None and (sdlmixer.Mix_PlayingMusic() or sdlmixer.Mix_PausedMusic()):
+            sdlmixer.Mix_HaltMusic()
+
+    def _free_music_track(self):
+        self.stop_music()
+        if self.music_enabled and sdlmixer is not None and self.music_track is not None:
+            sdlmixer.Mix_FreeMusic(self.music_track)
+        self.music_track = None
+        self.music_path = None
 
     # ======================
     # TEXTURE & IMAGE METHODS
@@ -437,6 +508,7 @@ class GameWindow:
 
     def stop_sound(self):
         """Stop all audio playback"""
+        self.stop_music()
         for dev in self.audio_devs.values():
             sdl2.SDL_PauseAudioDevice(dev, 1)
             sdl2.SDL_ClearQueuedAudio(dev)
@@ -722,6 +794,11 @@ class GameWindow:
 
     def close(self):
         """Close the game window and cleanup"""
+        self._free_music_track()
+        if self.music_enabled and sdlmixer is not None:
+            sdlmixer.Mix_CloseAudio()
+            sdlmixer.Mix_Quit()
+            self.music_enabled = False
         if self.game_controller:
             sdl2.SDL_GameControllerClose(self.game_controller)
             self.game_controller = None