import uuid
from datetime import datetime

from fastapi import APIRouter, Depends, HTTPException, Query, status
from fastapi.responses import StreamingResponse
from sqlalchemy.ext.asyncio import AsyncSession

from app.api.deps import get_current_user
from app.database import get_db
from app.models.user import User
from app.services.citation import export_citations_csv

router = APIRouter()


@router.get("/export/csv")
async def export_report(
    query_id: uuid.UUID = Query(...),
    format: str = Query("csv"),
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    if format != "csv":
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Only CSV format is supported",
        )

    try:
        csv_content = await export_citations_csv(db, current_user.id, query_id)
    except ValueError as e:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=str(e),
        )

    date_str = datetime.now().strftime("%Y%m%d")
    filename = f"geo-report-{date_str}.csv"

    return StreamingResponse(
        iter([csv_content]),
        media_type="text/csv",
        headers={
            "Content-Disposition": f'attachment; filename="{filename}"',
        },
    )