"""Deal API endpoints."""

from __future__ import annotations

from typing import Optional

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

from app.core.db import get_db
from app.core.deps import get_current_user
from app.models.deal import DealStage
from app.models.user import User
from app.schemas.deal import (
    DealCreate,
    DealOut,
    DealPipelineOut,
    DealStageUpdate,
    DealUpdate,
)
from app.services.deal_service import (
    InvalidAccount,
    create_deal as svc_create_deal,
    get_deal as svc_get_deal,
    get_pipeline,
    list_deals as svc_list_deals,
    soft_delete_deal as svc_soft_delete_deal,
    update_deal as svc_update_deal,
    update_stage as svc_update_stage,
)

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


@router.post(
    "/",
    response_model=DealOut,
    status_code=status.HTTP_201_CREATED,
    summary="Create a new deal",
)
async def create_deal(
    payload: DealCreate,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
) -> DealOut:
    try:
        deal = await svc_create_deal(
            db, payload, org_id=current_user.org_id, owner_id=current_user.id
        )
    except InvalidAccount as e:
        raise HTTPException(status_code=404, detail=str(e)) from e
    return DealOut.model_validate(deal)


@router.get(
    "/",
    response_model=list[DealOut],
    summary="List deals (paginated, filterable)",
)
async def list_deals(
    skip: int = Query(0, ge=0),
    limit: int = Query(20, ge=1, le=100),
    stage: Optional[DealStage] = None,
    owner_id: Optional[int] = None,
    account_id: Optional[int] = None,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
) -> list[DealOut]:
    deals = await svc_list_deals(
        db,
        org_id=current_user.org_id,
        skip=skip,
        limit=limit,
        stage=stage.value if stage else None,
        owner_id=owner_id,
        account_id=account_id,
    )
    return [DealOut.model_validate(d) for d in deals]


@router.get(
    "/pipeline",
    response_model=list[DealPipelineOut],
    summary="Get pipeline view (deals grouped by stage)",
)
async def get_pipeline_endpoint(
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
) -> list[DealPipelineOut]:
    pipeline = await get_pipeline(db, org_id=current_user.org_id)
    out: list[DealPipelineOut] = []
    for item in pipeline:
        out.append(
            DealPipelineOut(
                stage=DealStage(item["stage"]),
                count=int(item["count"]),
                total_value=float(item["total_value"]),
            )
        )
    return out


@router.get(
    "/{deal_id}",
    response_model=DealOut,
    summary="Get one deal",
)
async def get_deal(
    deal_id: int,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
) -> DealOut:
    deal = await svc_get_deal(db, deal_id, org_id=current_user.org_id)
    if deal is None:
        raise HTTPException(status_code=404, detail="Deal not found")
    return DealOut.model_validate(deal)


@router.patch(
    "/{deal_id}",
    response_model=DealOut,
    summary="Update a deal (does NOT change stage)",
)
async def update_deal(
    deal_id: int,
    payload: DealUpdate,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
) -> DealOut:
    deal = await svc_get_deal(db, deal_id, org_id=current_user.org_id)
    if deal is None:
        raise HTTPException(status_code=404, detail="Deal not found")
    updated = await svc_update_deal(db, deal, payload)
    return DealOut.model_validate(updated)


@router.patch(
    "/{deal_id}/stage",
    response_model=DealOut,
    summary="Change a deal's stage (creates DealStageHistory entry)",
)
async def update_deal_stage(
    deal_id: int,
    payload: DealStageUpdate,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
) -> DealOut:
    deal = await svc_get_deal(db, deal_id, org_id=current_user.org_id)
    if deal is None:
        raise HTTPException(status_code=404, detail="Deal not found")
    updated = await svc_update_stage(
        db, deal, payload.stage, changed_by=current_user.id, reason=payload.reason
    )
    return DealOut.model_validate(updated)


@router.delete(
    "/{deal_id}",
    status_code=status.HTTP_204_NO_CONTENT,
    response_class=Response,
    summary="Soft-delete a deal",
)
async def delete_deal(
    deal_id: int,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
) -> Response:
    deal = await svc_get_deal(db, deal_id, org_id=current_user.org_id)
    if deal is None:
        raise HTTPException(status_code=404, detail="Deal not found")
    await svc_soft_delete_deal(db, deal)
    return Response(status_code=status.HTTP_204_NO_CONTENT)


__all__ = ["router"]