import uuid
from pathlib import Path

from fastapi import APIRouter, Depends, HTTPException, Request, UploadFile, status

from app.core.deps import get_current_active_user
from app.core.rate_limit import RateLimiter
from app.core.storage import S3StorageBackend
from app.models.user import User
from app.schemas.upload import PresignedUrlRequest, PresignedUrlResponse, UploadResponse

router = APIRouter()

ALLOWED_TYPES = {"image/jpeg", "image/png", "image/gif", "image/webp"}
MAX_SIZE = 10 * 1024 * 1024  # 10MB


@router.post(
    "/image",
    response_model=UploadResponse,
    dependencies=[Depends(RateLimiter(times=20, seconds=60))],
)
async def upload_image(
    request: Request,
    file: UploadFile,
    current_user: User = Depends(get_current_active_user),
):
    if file.content_type not in ALLOWED_TYPES:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=f"Unsupported file type: {file.content_type}",
        )

    data = await file.read()
    if len(data) > MAX_SIZE:
        raise HTTPException(
            status_code=status.HTTP_413_REQUEST_ENTITY_TOO_LARGE,
            detail="File too large, max 10MB",
        )

    storage = request.app.state.storage
    url = storage.upload(data, file.filename or "image.jpg", file.content_type or "")

    return UploadResponse(url=url, filename=file.filename or "image.jpg")


@router.post("/presigned", response_model=PresignedUrlResponse)
async def get_presigned_upload_url(
    request: Request,
    payload: PresignedUrlRequest,
    current_user: User = Depends(get_current_active_user),
):
    storage = request.app.state.storage
    if not isinstance(storage, S3StorageBackend):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Presigned URLs only available with S3 storage backend",
        )

    ext = Path(payload.filename).suffix or ".jpg"
    file_key = f"images/{uuid.uuid4().hex}{ext}"
    upload_url = storage.generate_presigned_url(
        file_key, content_type=payload.content_type
    )
    public_url = storage._get_url(file_key)

    return PresignedUrlResponse(
        upload_url=upload_url,
        file_key=file_key,
        public_url=public_url,
    )