Initial commit

backend/services/effects.py

@@ -0,0 +1,120 @@
+"""
+Effect presets CRUD operations.
+"""
+
+from __future__ import annotations
+
+import json
+import uuid
+from typing import List, Optional
+
+from sqlalchemy.orm import Session
+from sqlalchemy.exc import IntegrityError
+
+from ..utils.effects import validate_effects_chain
+
+from ..database import EffectPreset as DBEffectPreset
+from ..models import EffectPresetResponse, EffectPresetCreate, EffectPresetUpdate, EffectConfig
+
+
+def _preset_response(p: DBEffectPreset) -> EffectPresetResponse:
+    """Convert a DB preset row to a Pydantic response."""
+    effects_chain = [EffectConfig(**e) for e in json.loads(p.effects_chain)]
+    return EffectPresetResponse(
+        id=p.id,
+        name=p.name,
+        description=p.description,
+        effects_chain=effects_chain,
+        is_builtin=p.is_builtin or False,
+        created_at=p.created_at,
+    )
+
+
+def list_presets(db: Session) -> List[EffectPresetResponse]:
+    """List all effect presets (built-in + user-created)."""
+    presets = db.query(DBEffectPreset).order_by(DBEffectPreset.sort_order, DBEffectPreset.name).all()
+    return [_preset_response(p) for p in presets]
+
+
+def get_preset(preset_id: str, db: Session) -> Optional[EffectPresetResponse]:
+    """Get a preset by ID."""
+    p = db.query(DBEffectPreset).filter_by(id=preset_id).first()
+    if not p:
+        return None
+    return _preset_response(p)
+
+
+def get_preset_by_name(name: str, db: Session) -> Optional[EffectPresetResponse]:
+    """Get a preset by name."""
+    p = db.query(DBEffectPreset).filter_by(name=name).first()
+    if not p:
+        return None
+    return _preset_response(p)
+
+
+def create_preset(data: EffectPresetCreate, db: Session) -> EffectPresetResponse:
+    """Create a new user effect preset."""
+
+    chain_dicts = [e.model_dump() for e in data.effects_chain]
+    error = validate_effects_chain(chain_dicts)
+    if error:
+        raise ValueError(error)
+
+    # Check for duplicate name before insert
+    existing = db.query(DBEffectPreset).filter_by(name=data.name).first()
+    if existing:
+        raise ValueError(f"A preset named '{data.name}' already exists")
+
+    preset = DBEffectPreset(
+        id=str(uuid.uuid4()),
+        name=data.name,
+        description=data.description,
+        effects_chain=json.dumps(chain_dicts),
+        is_builtin=False,
+    )
+    db.add(preset)
+    try:
+        db.commit()
+    except IntegrityError:
+        db.rollback()
+        raise ValueError(f"A preset named '{data.name}' already exists")
+    db.refresh(preset)
+    return _preset_response(preset)
+
+
+def update_preset(preset_id: str, data: EffectPresetUpdate, db: Session) -> Optional[EffectPresetResponse]:
+    """Update a user effect preset. Cannot modify built-in presets."""
+    preset = db.query(DBEffectPreset).filter_by(id=preset_id).first()
+    if not preset:
+        return None
+    if preset.is_builtin:
+        raise ValueError("Cannot modify built-in presets")
+
+    if data.name is not None:
+        preset.name = data.name
+    if data.description is not None:
+        preset.description = data.description
+    if data.effects_chain is not None:
+
+        chain_dicts = [e.model_dump() for e in data.effects_chain]
+        error = validate_effects_chain(chain_dicts)
+        if error:
+            raise ValueError(error)
+        preset.effects_chain = json.dumps(chain_dicts)
+
+    db.commit()
+    db.refresh(preset)
+    return _preset_response(preset)
+
+
+def delete_preset(preset_id: str, db: Session) -> bool:
+    """Delete a user effect preset. Cannot delete built-in presets."""
+    preset = db.query(DBEffectPreset).filter_by(id=preset_id).first()
+    if not preset:
+        return False
+    if preset.is_builtin:
+        raise ValueError("Cannot delete built-in presets")
+
+    db.delete(preset)
+    db.commit()
+    return True