no-mistakes(review): Fix orphaned photo files and add upload content-type validation

app/routers/tickets.py

@@ -224,6 +224,10 @@ async def check_sla(
 
 
 # ── Photo Uploads ────────────────────────────────────────────────────
+ALLOWED_EXTENSIONS = {".jpg", ".jpeg", ".png", ".gif", ".webp"}
+ALLOWED_MIME_TYPES = {"image/jpeg", "image/png", "image/gif", "image/webp"}
+
+
 @router.post("/{ticket_id}/photos", response_model=list[TicketPhotoOut], status_code=status.HTTP_201_CREATED)
 async def upload_photos(
     ticket_id: int,
@@ -236,18 +240,32 @@ async def upload_photos(
     # Verify ticket exists
     await ticket_service.get_ticket(db, ticket_id)
 
+    # Validate all files before any write operations
+    for file in files:
+        if file.content_type not in ALLOWED_MIME_TYPES:
+            raise HTTPException(
+                status_code=status.HTTP_400_BAD_REQUEST,
+                detail=f"Unsupported content type '{file.content_type}'. Allowed: image/jpeg, image/png, image/gif, image/webp",
+            )
+        ext = Path(file.filename or "photo.jpg").suffix.lower() if file.filename else ".jpg"
+        if ext not in ALLOWED_EXTENSIONS:
+            raise HTTPException(
+                status_code=status.HTTP_400_BAD_REQUEST,
+                detail=f"Unsupported file extension '{ext}'. Allowed: .jpg, .jpeg, .png, .gif, .webp",
+            )
+
     created_photos: list[TicketPhoto] = []
+    file_data: list[tuple[Path, bytes]] = []
     for file in files:
         # Generate unique filename
-        ext = Path(file.filename or "photo.jpg").suffix if file.filename else ".jpg"
+        ext = Path(file.filename or "photo.jpg").suffix.lower() if file.filename else ".jpg"
         unique_name = f"{uuid.uuid4().hex}{ext}"
         file_path = UPLOADS_DIR / unique_name
 
-        # Write file
         content = await file.read()
-        file_path.write_bytes(content)
+        file_data.append((file_path, content))
 
-        # Database record
+        # Database record (no file write yet)
         photo = TicketPhoto(
             ticket_id=ticket_id,
             photo_url=f"/uploads/{unique_name}",
@@ -259,6 +277,11 @@ async def upload_photos(
     await db.flush()
     for p in created_photos:
         await db.refresh(p)
+
+    # Write files to disk only after successful DB flush
+    for file_path, content in file_data:
+        file_path.write_bytes(content)
+
     return created_photos