fix: bundle FFmpeg offline, fix NoneType write crash in windowed apps, fallback to system PATH

fcco_converter/converter.py

@@ -16,14 +16,36 @@ import static_ffmpeg
 from .metadata import apply_id3_tags
 
 
+import sys
+import io
+import shutil
+
 def _ensure_ffmpeg() -> tuple[str, str]:
     """Stellt sicher, dass ffmpeg und ffprobe verfügbar sind.
 
     Returns:
         (ffmpeg_path, ffprobe_path)
     """
-    ffmpeg_path, ffprobe_path = static_ffmpeg.run.get_or_fetch_platform_executables_else_raise()
-    return ffmpeg_path, ffprobe_path
+    # 1. Behebe NoneType 'write' Fehler, wenn App im windowed-Modus gestartet wurde
+    if sys.stdout is None:
+        sys.stdout = io.StringIO()
+    if sys.stderr is None:
+        sys.stderr = io.StringIO()
+
+    # 2. Versuch 1: static_ffmpeg (jetzt direkt in der App gebündelt)
+    try:
+        ffmpeg_path, ffprobe_path = static_ffmpeg.run.get_or_fetch_platform_executables_else_raise()
+        return ffmpeg_path, ffprobe_path
+    except Exception:
+        pass
+
+    # 3. Versuch 2: System-FFmpeg (z.B. über winget, apt, brew) als Fallback
+    sys_ffmpeg = shutil.which("ffmpeg")
+    sys_ffprobe = shutil.which("ffprobe")
+    if sys_ffmpeg and sys_ffprobe:
+        return sys_ffmpeg, sys_ffprobe
+
+    raise RuntimeError("FFmpeg konnte weder im Bundle noch im System gefunden werden.")
 
 
 def get_duration(file_path: Path, ffprobe_path: str) -> float: