from fastapi import APIRouter, Depends, HTTPException, Form
from sqlalchemy.orm import Session
from sqlalchemy import desc
from typing import Optional
from datetime import datetime
from database import get_db
import models
from auth import require_admin

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

@router.get("")
def list_costs(
    cost_status: Optional[str] = None,
    cost_party_type: Optional[str] = None,
    db: Session = Depends(get_db), _=Depends(require_admin)
):
    q = db.query(models.RepairCost).join(models.Repair)
    if cost_status: q = q.filter(models.RepairCost.cost_status == cost_status)
    if cost_party_type: q = q.filter(models.RepairCost.cost_party_type == cost_party_type)
    q = q.order_by(desc(models.RepairCost.reviewed_at))

    result = []
    for cost in q.all():
        repair = cost.repair
        rids = [rr.report_id for rr in repair.report_links]
        charger_id, station_name, charger_type = None, None, None
        if rids:
            r = db.query(models.Report).filter_by(id=rids[0]).first()
            if r and r.charger:
                charger_id = r.charger_id
                station_name = r.charger.station_name
                charger_type = r.charger.charger_type.name if r.charger.charger_type else None
        result.append({
            "id": cost.id, "repair_id": cost.repair_id,
            "report_ids": rids, "charger_id": charger_id,
            "station_name": station_name, "charger_type": charger_type,
            "mechanic_name": repair.mechanic.name if repair.mechanic else None,
            "mechanic_company": repair.mechanic.company if repair.mechanic else None,
            "completed_at": repair.completed_at.isoformat() if repair.completed_at else None,
            "root_cause": cost.root_cause, "admin_note": cost.admin_note,
            "cost_party_type": cost.cost_party_type,
            "cost_party_custom": cost.cost_party_custom,
            "cost_amount": cost.cost_amount, "cost_status": cost.cost_status,
            "manufacturer_name": cost.manufacturer.name if cost.manufacturer else None,
            "reviewed_by_name": cost.reviewer.name if cost.reviewer else None,
            "reviewed_at": cost.reviewed_at.isoformat() if cost.reviewed_at else None,
        })
    return result

@router.get("/stats")
def cost_stats(db: Session = Depends(get_db), _=Depends(require_admin)):
    from sqlalchemy import func, extract
    now = datetime.now()
    monthly = db.query(func.sum(models.RepairCost.cost_amount)).filter(
        extract('year', models.RepairCost.reviewed_at) == now.year,
        extract('month', models.RepairCost.reviewed_at) == now.month,
    ).scalar() or 0
    pending = db.query(models.RepairCost).filter_by(cost_status="pending").count()
    return {"monthly_total": monthly, "pending_count": pending}

@router.post("/repair/{repair_id}")
def upsert_cost(
    repair_id: int,
    root_cause: str = Form(""),
    admin_note: str = Form(""),
    cost_party_type: str = Form(...),
    cost_party_manufacturer_id: Optional[int] = Form(None),
    cost_party_custom: str = Form(""),
    cost_amount: int = Form(0),
    cost_status: str = Form("pending"),
    db: Session = Depends(get_db),
    current_user: models.User = Depends(require_admin)
):
    repair = db.query(models.Repair).filter_by(id=repair_id).first()
    if not repair: raise HTTPException(404, "조치 내역을 찾을 수 없습니다.")

    cost = db.query(models.RepairCost).filter_by(repair_id=repair_id).first()
    if cost:
        cost.root_cause = root_cause; cost.admin_note = admin_note
        cost.cost_party_type = cost_party_type
        cost.cost_party_manufacturer_id = cost_party_manufacturer_id or None
        cost.cost_party_custom = cost_party_custom or None
        cost.cost_amount = cost_amount; cost.cost_status = cost_status
        cost.reviewed_by = current_user.id; cost.reviewed_at = datetime.now()
    else:
        cost = models.RepairCost(
            repair_id=repair_id, root_cause=root_cause, admin_note=admin_note,
            cost_party_type=cost_party_type,
            cost_party_manufacturer_id=cost_party_manufacturer_id or None,
            cost_party_custom=cost_party_custom or None,
            cost_amount=cost_amount, cost_status=cost_status,
            reviewed_by=current_user.id, reviewed_at=datetime.now()
        )
        db.add(cost)
    db.commit()
    return {"ok": True}