Initial commit

backend/database/session.py

@@ -0,0 +1,78 @@
+"""Engine creation, initialization, and session management."""
+
+import logging
+import uuid
+
+from sqlalchemy import create_engine
+from sqlalchemy.orm import sessionmaker
+
+from .. import config
+from .models import (
+    Base,
+    AudioChannel,
+    EffectPreset,
+    Generation,
+    GenerationVersion,
+    ProfileChannelMapping,
+    VoiceProfile,
+)
+from .migrations import run_migrations
+from .seed import backfill_generation_versions, seed_builtin_presets
+
+logger = logging.getLogger(__name__)
+
+# Initialized by init_db()
+engine = None
+SessionLocal = None
+_db_path = None
+
+
+def init_db() -> None:
+    """Initialize the database engine, run migrations, create tables, and seed data."""
+    global engine, SessionLocal, _db_path
+
+    _db_path = config.get_db_path()
+    _db_path.parent.mkdir(parents=True, exist_ok=True)
+
+    engine = create_engine(
+        f"sqlite:///{_db_path}",
+        connect_args={"check_same_thread": False},
+    )
+
+    SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+    run_migrations(engine)
+    Base.metadata.create_all(bind=engine)
+
+    # Create default audio channel if it doesn't exist
+    db = SessionLocal()
+    try:
+        default_channel = db.query(AudioChannel).filter(AudioChannel.is_default == True).first()
+        if not default_channel:
+            default_channel = AudioChannel(
+                id=str(uuid.uuid4()),
+                name="Default",
+                is_default=True,
+            )
+            db.add(default_channel)
+
+            for profile in db.query(VoiceProfile).all():
+                db.add(ProfileChannelMapping(
+                    profile_id=profile.id,
+                    channel_id=default_channel.id,
+                ))
+            db.commit()
+    finally:
+        db.close()
+
+    backfill_generation_versions(SessionLocal, Generation, GenerationVersion)
+    seed_builtin_presets(SessionLocal, EffectPreset)
+
+
+def get_db():
+    """Yield a database session (FastAPI dependency)."""
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()