refactor: split bulk-sync into backend/routers/sync.py

backend/routers/sync.py

@@ -0,0 +1,77 @@
+from fastapi import APIRouter, Depends
+from sqlalchemy.orm import Session
+from .. import models, schemas, auth
+from ..database import get_db
+import json
+
+router = APIRouter(
+    prefix="/sync",
+    tags=["Sync"]
+)
+
+
+@router.post("/bulk-sync")
+def bulk_sync(
+    payload: schemas.SyncPayload,
+    db: Session = Depends(get_db),
+    current_user: auth.TokenData = Depends(auth.get_current_user)
+):
+    """[C-01] Bulk sync offline operations — only for authenticated users."""
+    results = {"success": [], "errors": []}
+
+    for op in payload.operations:
+        try:
+            # DEDUPLICATION CHECK: If this UUID already exists, skip it
+            if op.uuid:
+                existing = db.query(models.AuditLog).filter(models.AuditLog.uuid == op.uuid).first()
+                if existing:
+                    results["success"].append({"barcode": op.barcode, "type": op.type, "note": "Already synced"})
+                    continue
+
+            item = db.query(models.Item).filter(models.Item.barcode == op.barcode).first()
+            if not item:
+                results["errors"].append({"barcode": op.barcode, "error": "Item not found"})
+                continue
+
+            if op.type == "CHECK_IN":
+                item.quantity += op.quantity
+                change = op.quantity
+            elif op.type == "CHECK_OUT" or op.type == "TRASH":
+                if item.quantity < op.quantity:
+                    results["errors"].append({"barcode": op.barcode, "error": f"Insufficient stock (Available: {item.quantity})"})
+                    continue
+                item.quantity -= op.quantity
+                change = -op.quantity
+            else:
+                results["errors"].append({"barcode": op.barcode, "error": f"Invalid operation type: {op.type}"})
+                continue
+
+            # Log audit with original offline timestamp and UUID
+            item_snapshot = {
+                "barcode": item.barcode,
+                "name": item.name,
+                "category": item.category,
+                "part_number": item.part_number
+            }
+
+            audit = models.AuditLog(
+                user_id=current_user.sub,
+                action=op.type,
+                target_item_id=item.id,
+                target_item_name=item.name,
+                target_item_pn=item.part_number,
+                target_item_barcode=item.barcode,
+                target_snapshot=json.dumps(item_snapshot),
+                quantity_change=change,
+                timestamp=op.timestamp,
+                uuid=op.uuid,
+                details="Offline Synchronization"
+            )
+            db.add(audit)
+            results["success"].append({"barcode": op.barcode, "type": op.type})
+
+        except Exception as e:
+            results["errors"].append({"barcode": op.barcode, "error": str(e)})
+
+    db.commit()
+    return results