Fix focus endpoint crash

app/main.py

@@ -1,3 +1,5 @@
+from io import BytesIO
+
 from fastapi import FastAPI, File, Form, HTTPException, UploadFile
 from fastapi.responses import HTMLResponse, StreamingResponse
 from app.config import settings
@@ -113,7 +115,18 @@ async def focus(
 
     try:
         payload = await file.read()
-        return process_image(payload, file.filename or "upload", buffer_ratio=buffer_ratio, detector=detector)
+        result = process_image(payload, file.filename or "upload", buffer_ratio=buffer_ratio, detector=detector)
+        return {
+            "filename": result["filename"],
+            "detector": result["detector"],
+            "method": result["method"],
+            "buffer_ratio": result["buffer_ratio"],
+            "detected_bbox": result["detected_bbox"],
+            "square_bbox": result["square_bbox"],
+            "source_size": result["source_size"],
+            "crop_data_url": result["crop_data_url"],
+            "annotated_data_url": result["annotated_data_url"],
+        }
     except ValueError as exc:
         raise HTTPException(status_code=400, detail=str(exc)) from exc
 
@@ -129,6 +142,6 @@ async def focus_image(
     try:
         payload = await file.read()
         result = process_image(payload, file.filename or "upload", buffer_ratio=buffer_ratio, detector=detector)
-        return StreamingResponse(result["crop_bytes_io"], media_type=result["mime_type"])
+        return StreamingResponse(BytesIO(result["crop_bytes"]), media_type=result["mime_type"])
     except ValueError as exc:
         raise HTTPException(status_code=400, detail=str(exc)) from exc

app/vision.py

@@ -1,7 +1,6 @@
 from __future__ import annotations
 
 from dataclasses import dataclass
-from io import BytesIO
 from pathlib import Path
 from typing import Any
 
@@ -91,7 +90,7 @@ def detect_face(image: np.ndarray) -> BBox | None:
     faces = FACE_CASCADE.detectMultiScale(gray, scaleFactor=1.08, minNeighbors=5, minSize=(24, 24))
     if len(faces) == 0:
         return None
-    x, y, w, h = max((map(int, face) for face in faces), key=lambda rect: rect[2] * rect[3])
+    x, y, w, h = max((tuple(map(int, face)) for face in faces), key=lambda rect: rect[2] * rect[3])
     return BBox(x=x, y=y, w=w, h=h)
 
 
@@ -192,5 +191,5 @@ def process_image(image_bytes: bytes, filename: str, buffer_ratio: float = 0.15,
         "crop_data_url": _data_url(crop_bytes, mime_type),
         "annotated_data_url": _data_url(annotated_bytes, mime_type),
         "mime_type": mime_type,
-        "crop_bytes_io": BytesIO(crop_bytes),
+        "crop_bytes": crop_bytes,
     }