"""DATEV export router: create exports, list exports, download CSV."""

import uuid

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

from app.database import get_db
from app.dependencies import get_current_user, get_pagination
from app.models.user import User
from app.schemas.datev import (
    DATEVExportCreate,
    DATEVExportListResponse,
    DATEVExportResponse,
)
from app.services import datev_service

router = APIRouter(prefix="/datev", tags=["datev"])


@router.post("/export", response_model=DATEVExportResponse, status_code=status.HTTP_201_CREATED)
async def create_export(
    body: DATEVExportCreate,
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    """Create a DATEV export for the given date range.

    Queries all completed sales within the date range and generates a CSV file.
    """
    export = await datev_service.create_export(
        db,
        start_date=body.start_date,
        end_date=body.end_date,
    )
    return DATEVExportResponse.model_validate(export)


@router.get("/exports", response_model=DATEVExportListResponse, status_code=status.HTTP_200_OK)
async def list_exports(
    db: AsyncSession = Depends(get_db),
    pagination: dict = Depends(get_pagination),
    current_user: User = Depends(get_current_user),
):
    """List all DATEV exports with pagination."""
    exports, total = await datev_service.list_exports(
        db,
        page=pagination["page"],
        page_size=pagination["page_size"],
    )
    return DATEVExportListResponse(
        items=[DATEVExportResponse.model_validate(e) for e in exports],
        total=total,
        page=pagination["page"],
        page_size=pagination["page_size"],
    )


@router.get("/exports/{export_id}/download", status_code=status.HTTP_200_OK)
async def download_export(
    export_id: uuid.UUID,
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(get_current_user),
):
    """Download a DATEV export as CSV file."""
    result = await datev_service.get_export_csv(db, export_id)
    if result is None:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail={"error": {"code": "EXPORT_NOT_FOUND", "message": "DATEV export not found"}},
        )
    filename, csv_bytes = result
    return Response(
        content=csv_bytes,
        media_type="text/csv",
        headers={"Content-Disposition": f'attachment; filename="{filename}"'},
    )