import imghdr
from wsgiref.util import FileWrapper

import structlog
from django.conf import settings
from django.contrib.auth.decorators import login_required
from django.http import HttpResponse, StreamingHttpResponse
from django.shortcuts import get_object_or_404
from wagtail.images.exceptions import InvalidFilterSpecError
from wagtail.images.models import SourceImageIOError

from vbv_lernwelt.media_files.models import UserImage

logger = structlog.get_logger(__name__)


@login_required
def user_image(request, image_id):
    image = get_object_or_404(UserImage, id=image_id)

    filter_spec = request.GET.get("filter", "original")

    try:
        rendition = image.get_rendition(filter_spec)

        rendition.file.open("rb")
        image_format = imghdr.what(rendition.file)

        return StreamingHttpResponse(
            FileWrapper(rendition.file),
            content_type=(
                f"image/{image_format}" if image_format else "binary/octet-stream"
            ),
        )
    except SourceImageIOError:
        return HttpResponse(
            "Source image file not found", content_type="text/plain", status=410
        )
    except InvalidFilterSpecError:
        return HttpResponse(
            "Invalid filter spec: " + filter_spec,
            content_type="text/plain",
            status=400,
        )
    except Exception:
        if settings.APP_ENVIRONMENT.startswith("local"):
            # do not spam the console
            logger.warning("Error while serving image")
        else:
            logger.exception(
                "Error while serving image", exc_info=True, label="s3_mediafiles"
            )
        return HttpResponse(
            "Error while serving image", content_type="text/plain", status=400
        )