import uuid

from fastapi import FastAPI, UploadFile
from fastapi.middleware.cors import CORSMiddleware
import boto3
from httpx import AsyncClient
from PIL import Image, UnidentifiedImageError
from io import BytesIO

from app.config import settings
from app.shemas import SImage
from app.tasks.tasks import resize_image
from app.exceptions import IncorrectFileException, BrokenFileException, UnexpectedErrorException

app = FastAPI(
    title="Сервер загрузки изображений в S3",
    root_path="/api",
)

origins = []

app.add_middleware(
    CORSMiddleware,
    allow_origins=origins,
    allow_credentials=True,
    allow_methods=["GET", "POST", "PUT", "DELETE", "OPTIONS", "PATCH"],
    allow_headers=[
        "Content-Type",
        "Set-Cookie",
        "Access-Control-Allow-Headers",
        "Authorization",
        "Accept"
    ],
)

s3 = boto3.client('s3',
                  endpoint_url=settings.S3_ENDPOINT_URL,
                  region_name=settings.REGION_NAME,
                  aws_access_key_id=settings.AWS_ACCESS_KEY_ID,
                  aws_secret_access_key=settings.AWS_SECRET_ACCESS_KEY)


@app.post("/upload_image", response_model=SImage)
async def upload_image(file: UploadFile, target_width: int = 250):

    try:
        content = await file.read()

        image = Image.open(BytesIO(content))
        image_type = image.format.lower()
        if image_type not in ["png", "jpeg"]:
            raise IncorrectFileException

        result = resize_image.delay({"file": content}, target_width)

        result_data = result.get()
        new_image = result_data["new_image"]

    except UnidentifiedImageError:
        raise IncorrectFileException
    except (OSError, SyntaxError):
        raise BrokenFileException
    except Exception:
        raise UnexpectedErrorException

    object_key = str(uuid.uuid4()) + f".{image_type}"

    try:
        post = s3.generate_presigned_post(settings.BUCKET_NAME, object_key,
                                          Fields={"Content-Type": "image/webp"},
                                          Conditions=[["eq", "$content-type", "image/webp"]])
        async with AsyncClient() as ac:
            await ac.post(post["url"], data=post["fields"], files=[("file", (object_key, new_image))])

        response = s3.generate_presigned_url('get_object',
                                             Params={'Bucket': settings.BUCKET_NAME,
                                                     'Key': object_key},
                                             ExpiresIn=36000)

        return {"resized_image_link": response}
    except Exception:
        raise UnexpectedErrorException