From 60a417dc643df753d20de6bd4b0745672fc80c2d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=B6rn-Michael=20Miehe?= <jmm@yavook.de>
Date: Sun, 30 Nov 2025 14:19:05 +0100
Subject: [PATCH] API: use `ImageData` type

---
 api/advent22_api/core/helpers.py | 44 ++++++++++++++++++++++++++------
 api/advent22_api/routers/user.py | 36 +++++++++++++-------------
 2 files changed, 54 insertions(+), 26 deletions(-)

diff --git a/api/advent22_api/core/helpers.py b/api/advent22_api/core/helpers.py
index b75e31c..bbf7260 100644
--- a/api/advent22_api/core/helpers.py
+++ b/api/advent22_api/core/helpers.py
@@ -1,3 +1,4 @@
+import base64
 import itertools
 import random
 import re
@@ -5,9 +6,9 @@ from datetime import date, datetime, timedelta
 from io import BytesIO
 from typing import Any, Awaitable, Callable, Iterable, Self, Sequence, TypeVar
 
-from fastapi.responses import StreamingResponse
 from PIL import Image as PILImage
 from PIL.Image import Image, Resampling
+from pydantic import BaseModel
 
 from .config import get_config
 from .dav.webdav import WebDAV
@@ -115,25 +116,51 @@ async def load_image(file_name: str) -> Image:
     return PILImage.open(BytesIO(await WebDAV.read_bytes(file_name)))
 
 
-async def api_return_ico(img: Image) -> StreamingResponse:
+class ImageData(BaseModel):
+    width: int
+    height: int
+    aspect_ratio: float
+    data_url: str
+
+    @classmethod
+    def create(
+        cls,
+        *,
+        media_type: str,
+        content: BytesIO,
+        width: int,
+        height: int,
+    ) -> Self:
+        img_data = base64.b64encode(content.getvalue()).decode("utf-8")
+
+        return cls(
+            width=width,
+            height=height,
+            aspect_ratio=width / height,
+            data_url=f"data:{media_type};base64,{img_data}",
+        )
+
+
+async def api_return_ico(img: Image) -> ImageData:
     """
     ICO-Bild mit API zurückgeben
     """
 
-    # JPEG-Daten in Puffer speichern
+    # ICO-Daten in Puffer speichern (256px)
     img_buffer = BytesIO()
     img.resize(size=(256, 256), resample=Resampling.LANCZOS)
     img.save(img_buffer, format="ICO")
-    img_buffer.seek(0)
 
     # zurückgeben
-    return StreamingResponse(
+    return ImageData.create(
         media_type="image/x-icon",
         content=img_buffer,
+        width=img.width,
+        height=img.height,
     )
 
 
-async def api_return_jpeg(img: Image) -> StreamingResponse:
+async def api_return_jpeg(img: Image) -> ImageData:
     """
     JPEG-Bild mit API zurückgeben
     """
@@ -141,12 +168,13 @@ async def api_return_jpeg(img: Image) -> StreamingResponse:
     # JPEG-Daten in Puffer speichern
     img_buffer = BytesIO()
     img.save(img_buffer, format="JPEG", quality=85)
-    img_buffer.seek(0)
 
     # zurückgeben
-    return StreamingResponse(
+    return ImageData.create(
         media_type="image/jpeg",
         content=img_buffer,
+        width=img.width,
+        height=img.height,
     )
 
 
diff --git a/api/advent22_api/routers/user.py b/api/advent22_api/routers/user.py
index 48c0e54..20ee228 100644
--- a/api/advent22_api/routers/user.py
+++ b/api/advent22_api/routers/user.py
@@ -1,25 +1,31 @@
 from datetime import datetime
 
 from fastapi import APIRouter, Depends, HTTPException, status
-from fastapi.responses import StreamingResponse
 from PIL.Image import Image
 
-from ..core.calendar_config import CalendarConfig, DoorsSaved, get_calendar_config
+from ..core.calendar_config import (
+    CalendarConfig,
+    DoorsSaved,
+    get_calendar_config,
+)
 from ..core.config import Config, Site, get_config
 from ..core.depends import get_all_event_dates, get_day_image
-from ..core.helpers import EventDates, api_return_ico, api_return_jpeg, load_image
+from ..core.helpers import (
+    EventDates,
+    ImageData,
+    api_return_ico,
+    api_return_jpeg,
+    load_image,
+)
 from ._security import user_can_view_day, user_is_admin, user_visible_days
 
 router = APIRouter(prefix="/user", tags=["user"])
 
 
-@router.get(
-    "/background_image",
-    response_class=StreamingResponse,
-)
+@router.get("/background_image")
 async def get_background_image(
     cal_cfg: CalendarConfig = Depends(get_calendar_config),
-) -> StreamingResponse:
+) -> ImageData:
     """
     Hintergrundbild laden
     """
@@ -27,13 +33,10 @@ async def get_background_image(
     return await api_return_jpeg(await load_image(f"files/{cal_cfg.background}"))
 
 
-@router.get(
-    "/favicon",
-    response_class=StreamingResponse,
-)
+@router.get("/favicon")
 async def get_favicon(
     cal_cfg: CalendarConfig = Depends(get_calendar_config),
-) -> StreamingResponse:
+) -> ImageData:
     """
     Favicon laden
     """
@@ -68,15 +71,12 @@ async def get_doors(
     return [door for door in cal_cfg.doors if door.day in visible_days]
 
 
-@router.get(
-    "/image_{day}",
-    response_class=StreamingResponse,
-)
+@router.get("/image_{day}")
 async def get_image_for_day(
     user_can_view: bool = Depends(user_can_view_day),
     is_admin: bool = Depends(user_is_admin),
     image: Image | None = Depends(get_day_image),
-) -> StreamingResponse:
+) -> ImageData:
     """
     Bild für einen Tag erstellen
     """