package at.ac.tuwien.sepm.assignment.groupphase.missioncontrol.service;

import at.ac.tuwien.sepm.assignment.groupphase.exception.ElementNotFoundException;
import at.ac.tuwien.sepm.assignment.groupphase.exception.InvalidVehicleException;
import at.ac.tuwien.sepm.assignment.groupphase.exception.PersistenceException;
import at.ac.tuwien.sepm.assignment.groupphase.exception.ServiceException;
import at.ac.tuwien.sepm.assignment.groupphase.missioncontrol.dao.VehicleDAO;
import at.ac.tuwien.sepm.assignment.groupphase.missioncontrol.dto.Vehicle;
import at.ac.tuwien.sepm.assignment.groupphase.missioncontrol.dto.Vehicle.ConstructionType;
import at.ac.tuwien.sepm.assignment.groupphase.missioncontrol.dto.Vehicle.Status;
import java.util.EnumSet;
import java.util.Set;
import java.util.stream.Collectors;
import org.springframework.stereotype.Service;
import org.springframework.util.CollectionUtils;

@Service
public class VehicleServiceImpl implements VehicleService {

    private VehicleDAO vehiclePersistence;

    public VehicleServiceImpl(VehicleDAO vehiclePersistence) {
        this.vehiclePersistence = vehiclePersistence;
    }

    public long add(Vehicle vehicle) throws InvalidVehicleException, ServiceException {
        if (!CollectionUtils.isEmpty(vehicle.registrations())) {
            throw new InvalidVehicleException(
                    "Fahrzeug kann nicht mit Anmeldungen erstellt werden");
        }

        validateVehicle(vehicle);
        try {
            vehiclePersistence.add(vehicle);
        } catch (PersistenceException e) {
            throw new ServiceException(e);
        }
        return 0;
    }

    public Vehicle update(Vehicle vehicle) throws InvalidVehicleException, ServiceException {
        validateVehicle(vehicle);
        try {
            vehiclePersistence.update(vehicle);
        } catch (ElementNotFoundException e) {
            throw new ServiceException("Element not found", e);
        } catch (PersistenceException e) {
            throw new ServiceException(e);
        }
        return vehicle;
    }

    protected static void validateVehicle(Vehicle vehicle) throws InvalidVehicleException {
        switch (vehicle.type()) {
            case RTW:
                if (vehicle.constructionType() == ConstructionType.NORMAL) {
                    throw new InvalidVehicleException("RTW darf kein Normales Dach haben");
                } else if (vehicle.constructionType() == ConstructionType.MITTELHOCHDACH) {
                    throw new InvalidVehicleException("RTW darf kein Mittelhochdach haben");
                }
                break;
            case KTW:
                if (vehicle.constructionType() == ConstructionType.NORMAL) {
                    throw new InvalidVehicleException("KTW darf kein Normales Dach haben");
                }
                break;
            case KTW_B:
                if (vehicle.constructionType() == ConstructionType.NORMAL) {
                    throw new InvalidVehicleException("KTW-B darf kein Normales Dach haben");
                }
                break;
            case NEF:
                if (vehicle.constructionType() == ConstructionType.MITTELHOCHDACH) {
                    throw new InvalidVehicleException("NEF darf kein Mittelhochdach haben");
                } else if (vehicle.constructionType() == ConstructionType.HOCHDACH) {
                    throw new InvalidVehicleException("NEF darf kein Hochdach haben");
                }
                break;
            case NAH:
                if (vehicle.constructionType() == ConstructionType.MITTELHOCHDACH) {
                    throw new InvalidVehicleException("NEF darf kein Mittelhochdach haben");
                } else if (vehicle.constructionType() == ConstructionType.HOCHDACH) {
                    throw new InvalidVehicleException("NEF darf kein Hochdach haben");
                }
                break;
            case BKTW:
                break;
            default:
                throw new IllegalStateException("BUG: invalid vehicle type" + vehicle.type());
        }
    }

    @Override
    public Set<Vehicle> list(EnumSet<Status> statuses) throws ServiceException {
        if (statuses == null) {
            throw new ServiceException("Statuses may not be null");
        }

        Set<Vehicle> vehicles;

        try {
            vehicles = vehiclePersistence.list();
        } catch (PersistenceException e) {
            throw new ServiceException(e);
        }

        return vehicles.stream()
                .filter(vehicle -> statuses.contains(vehicle.status()))
                .collect(Collectors.toSet());
    }

    @Override
    public void remove(long id) throws InvalidVehicleException, ServiceException {
        throw new UnsupportedOperationException();
    }
}