from fastapi import APIRouter, Depends, Header, HTTPException, status
from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from app.api.deps import (
    ensure_service_employee,
    get_current_telegram_user,
    get_or_create_telegram_user,
    log_audit,
    require_internal_api_token,
)
from app.db.session import get_session
from app.models.car import (
    Car,
    CarServiceLink,
    ServiceCenter,
    ServiceCenterVerification,
    ServiceEmployee,
    ServiceInboxMessage,
    ServiceVisit,
)
from app.models.user import User
from app.schemas.service_center import (
    CarServiceLinkCreate,
    CarServiceLinkRead,
    ServiceCenterCreate,
    ServiceCenterRead,
    ServiceCenterVerificationCreate,
    ServiceCenterVerificationRead,
    ServiceEmployeeInvite,
    ServiceEmployeeRead,
    ServiceInboxCreate,
    ServiceInboxRead,
    ServiceVisitCreate,
    ServiceVisitRead,
    VehicleSearchRequest,
    VehicleSearchResult,
)
from app.services.vehicle_identity import mask_license_plate, mask_vin

router = APIRouter(prefix="/service-centers", tags=["service-centers"])

@router.post("", response_model=ServiceCenterRead, status_code=status.HTTP_201_CREATED)
async def create_service_center(
    payload: ServiceCenterCreate,
    session: AsyncSession = Depends(get_session),
    current_user: User = Depends(get_current_telegram_user),
) -> ServiceCenter:
    center = ServiceCenter(
        name=payload.display_name,
        display_name=payload.display_name,
        legal_name=payload.legal_name,
        country=payload.country.upper() if payload.country else None,
        city=payload.city,
        address=payload.address,
        phone=payload.phone,
        contact_phone=payload.contact_phone or payload.phone,
        telegram_chat_id=payload.telegram_chat_id,
        business_registration_number=payload.business_registration_number,
        owner_user_id=current_user.id,
        verification_status="pending",
    )
    session.add(center)
    await session.flush()
    employee = ServiceEmployee(
        service_center_id=center.id,
        user_id=current_user.id,
        role="owner",
        status="active",
    )
    session.add(employee)
    await log_audit(session, actor=current_user, action="service_center.create", target_type="service_center", target_id=center.id)
    await session.commit()
    await session.refresh(center)
    return center


@router.get("/my", response_model=list[ServiceCenterRead])
async def my_service_centers(
    session: AsyncSession = Depends(get_session),
    current_user: User = Depends(get_current_telegram_user),
) -> list[ServiceCenter]:
    result = await session.execute(
        select(ServiceCenter)
        .join(ServiceEmployee, ServiceEmployee.service_center_id == ServiceCenter.id)
        .where(ServiceEmployee.user_id == current_user.id, ServiceEmployee.status == "active")
        .order_by(ServiceCenter.created_at.desc())
    )
    return list(result.scalars())


@router.get("", response_model=list[ServiceCenterRead])
async def list_service_centers(
    session: AsyncSession = Depends(get_session),
    x_internal_api_token: str | None = Header(default=None, alias="X-Internal-API-Token"),
) -> list[ServiceCenter]:
    require_internal_api_token(x_internal_api_token)
    result = await session.execute(select(ServiceCenter).order_by(ServiceCenter.name))
    return list(result.scalars())


@router.post("/{service_center_id}/verification", response_model=ServiceCenterVerificationRead)
async def submit_verification(
    service_center_id: int,
    payload: ServiceCenterVerificationCreate,
    session: AsyncSession = Depends(get_session),
    current_user: User = Depends(get_current_telegram_user),
) -> ServiceCenterVerification:
    await ensure_service_employee(session, service_center_id, current_user, {"owner", "manager"})
    verification = ServiceCenterVerification(
        service_center_id=service_center_id,
        submitted_documents=payload.submitted_documents,
        comment=payload.comment,
        status="pending",
    )
    session.add(verification)
    center = await session.get(ServiceCenter, service_center_id)
    if center:
        center.verification_status = "pending"
    await log_audit(session, actor=current_user, action="service_center.verification.submit", target_type="service_center", target_id=service_center_id)
    await session.commit()
    await session.refresh(verification)
    return verification


@router.post("/{service_center_id}/employees/invite", response_model=ServiceEmployeeRead)
async def invite_employee(
    service_center_id: int,
    payload: ServiceEmployeeInvite,
    session: AsyncSession = Depends(get_session),
    current_user: User = Depends(get_current_telegram_user),
) -> ServiceEmployee:
    await ensure_service_employee(session, service_center_id, current_user, {"owner", "manager"})
    user = await get_or_create_telegram_user(session, telegram_id=payload.telegram_id)
    result = await session.execute(
        select(ServiceEmployee).where(
            ServiceEmployee.service_center_id == service_center_id,
            ServiceEmployee.user_id == user.id,
        )
    )
    employee = result.scalar_one_or_none()
    if employee is None:
        employee = ServiceEmployee(
            service_center_id=service_center_id,
            user_id=user.id,
            role=payload.role,
            permissions=payload.permissions,
            status="invited",
        )
        session.add(employee)
    else:
        employee.role = payload.role
        employee.permissions = payload.permissions
        employee.status = "invited"
    await log_audit(session, actor=current_user, action="service_employee.invite", target_type="service_center", target_id=service_center_id, metadata={"telegram_id": payload.telegram_id})
    await session.commit()
    await session.refresh(employee)
    return employee


@router.get("/{service_center_id}/visits", response_model=list[ServiceVisitRead])
async def service_center_visits(
    service_center_id: int,
    session: AsyncSession = Depends(get_session),
    current_user: User = Depends(get_current_telegram_user),
) -> list[ServiceVisit]:
    await ensure_service_employee(session, service_center_id, current_user)
    result = await session.execute(
        select(ServiceVisit)
        .where(ServiceVisit.service_center_id == service_center_id)
        .order_by(ServiceVisit.visit_date.desc(), ServiceVisit.id.desc())
    )
    return list(result.scalars())


@router.post("/{service_center_id}/visits", response_model=ServiceVisitRead, status_code=status.HTTP_201_CREATED)
async def create_visit(
    service_center_id: int,
    payload: ServiceVisitCreate,
    session: AsyncSession = Depends(get_session),
    current_user: User = Depends(get_current_telegram_user),
) -> ServiceVisit:
    employee = await ensure_service_employee(session, service_center_id, current_user, {"owner", "manager", "receptionist"})
    vehicle = await session.get(Car, payload.vehicle_id)
    if vehicle is None:
        raise HTTPException(status_code=404, detail="Vehicle not found")
    center = await session.get(ServiceCenter, service_center_id)
    if center and center.verification_status not in {"verified", "pending"}:
        raise HTTPException(status_code=403, detail="Service center is not allowed to create visits")
    visit = ServiceVisit(
        service_center_id=service_center_id,
        vehicle_id=payload.vehicle_id,
        created_by_employee_id=employee.id,
        visit_date=payload.visit_date,
        odometer=payload.odometer,
        notes=payload.notes,
        total_cost=payload.total_cost,
        currency=payload.currency,
        status="draft",
    )
    session.add(visit)
    await log_audit(session, actor=current_user, action="service_visit.create", target_type="service_visit", metadata={"vehicle_id": payload.vehicle_id})
    await session.commit()
    await session.refresh(visit)
    return visit


@router.post("/{service_center_id}/vehicle-access/request")
async def request_vehicle_access(
    service_center_id: int,
    payload: VehicleSearchRequest,
    session: AsyncSession = Depends(get_session),
    current_user: User = Depends(get_current_telegram_user),
) -> VehicleSearchResult:
    await ensure_service_employee(session, service_center_id, current_user, {"owner", "manager", "receptionist"})
    stmt = select(Car)
    if payload.vin:
        stmt = stmt.where(Car.vin_normalized == payload.vin)
    elif payload.license_plate:
        stmt = stmt.where(Car.license_plate_normalized == payload.license_plate)
        if payload.country_code:
            stmt = stmt.where(Car.license_plate_country == payload.country_code.upper())
    else:
        raise HTTPException(status_code=400, detail="license_plate or vin is required")
    vehicle = (await session.execute(stmt.limit(1))).scalar_one_or_none()
    await log_audit(
        session,
        actor=current_user,
        action="vehicle_access.request",
        target_type="vehicle",
        target_id=vehicle.id if vehicle else None,
        metadata={"service_center_id": service_center_id, "found": bool(vehicle)},
    )
    await session.commit()
    if vehicle is None:
        return VehicleSearchResult(access_status="not_found")
    return VehicleSearchResult(
        vehicle_id=vehicle.id,
        make=vehicle.make,
        model=vehicle.model,
        year=vehicle.year,
        masked_license_plate=mask_license_plate(vehicle.license_plate_display or vehicle.plate_number),
        masked_vin=mask_vin(vehicle.vin_normalized or vehicle.vin),
        access_status="request_logged",
    )


@router.post("/links", response_model=CarServiceLinkRead, status_code=status.HTTP_201_CREATED)
async def link_car_to_service(
    payload: CarServiceLinkCreate,
    session: AsyncSession = Depends(get_session),
    x_internal_api_token: str | None = Header(default=None, alias="X-Internal-API-Token"),
) -> CarServiceLink:
    require_internal_api_token(x_internal_api_token)
    if await session.get(Car, payload.car_id) is None:
        raise HTTPException(status_code=404, detail="Car not found")
    if await session.get(ServiceCenter, payload.service_center_id) is None:
        raise HTTPException(status_code=404, detail="Service center not found")
    link = CarServiceLink(**payload.model_dump())
    session.add(link)
    await session.commit()
    await session.refresh(link)
    return link


@router.post("/inbox", response_model=ServiceInboxRead, status_code=status.HTTP_201_CREATED)
async def receive_service_message(
    payload: ServiceInboxCreate,
    session: AsyncSession = Depends(get_session),
    x_internal_api_token: str | None = Header(default=None, alias="X-Internal-API-Token"),
) -> ServiceInboxMessage:
    require_internal_api_token(x_internal_api_token)
    service_center_id = payload.service_center_id
    if not service_center_id and payload.source_chat_id:
        result = await session.execute(
            select(ServiceCenter).where(ServiceCenter.telegram_chat_id == payload.source_chat_id)
        )
        center = result.scalar_one_or_none()
        service_center_id = center.id if center else None

    message = ServiceInboxMessage(
        source_chat_id=payload.source_chat_id,
        raw_text=payload.raw_text,
        car_id=payload.car_id,
        service_center_id=service_center_id,
        parsed_status="pending",
    )
    session.add(message)
    await session.commit()
    await session.refresh(message)
    return message