package it.bgates.remotebe.service;

import it.bgates.remotebe.entities.Device;
import it.bgates.remotebe.entities.Phone;
import it.bgates.remotebe.entities.User;
import it.bgates.remotebe.exception.*;
import it.bgates.remotebe.repository.PhoneRepository;
import it.bgates.remotebe.repository.UserRepository;
import jakarta.persistence.EntityManager;
import jakarta.persistence.TypedQuery;
import jakarta.validation.Valid;
import lombok.RequiredArgsConstructor;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.security.Principal;
import java.time.LocalDateTime;
import java.util.List;
import java.util.Optional;

@Service
@RequiredArgsConstructor
public class PhoneService extends BaseService {
    private final PhoneRepository phoneRepository;
    private final UserRepository userRepository;
    private final EntityManager entityManager;

    // private final DeviceService deviceService;
    // private final BillingService billingService;
    //private final ConfigService configService;

    public List<Phone> getPhonesByDeviceId(Integer deviceId, Principal principal) throws UserNotFoundException, NotFoundException {
    /*
        Device device = deviceService.getDevice(deviceId, principal);

        if (device == null) {
            throw new NotFoundException("Device not found");
        }

     */

        return phoneRepository.findByDeviceId(deviceId);
    }

    @Transactional
    public Phone addPhone(@Valid Phone phone, Principal principal)
            throws UserNotFoundException,
            InvalidBillingTypeException,
            InsufficientCreditException,
            AlreadyPresentException, NullValueNotAllowed {

        if (phone.getDevice() == null) {
            throw new NullValueNotAllowed("Dispositivo non specificato");
        }

        // del numero di telefono tieni solo le cifre e il carattere +
        phone.setPhoneNumber(phone.getPhoneNumber().replaceAll("[^0-9+]", ""));

        if (phone.getId() == null) {

            /*
            if (!billingService.sufficientBalance(principal, configService.getBillingTypeCost(BillingType.USER_ADD))) {
                throw new InsufficientCreditException("Saldo GT-Coins insufficiente per effettuare l'operazione");
            }

             */

            // check if the same phone number is already present in the device
            int cnt = phoneRepository.countPhones(phone.getDevice().getId(), phone.getPhoneNumber());
            if (cnt > 9) {
                throw new AlreadyPresentException("Numero di telefono già presente nel dispositivo");
            }

            phone.setCreateDate(LocalDateTime.now());
        }

        if (phone.getDeleted() == null) {
            phone.setDeleted(false);
        }

        phone.setModified(true);
        phone.setSynched(false);

        Phone addedPhone = phoneRepository.save(phone);

        /*
        billingService.addBilling(principal, phone.getDevice(), BillingType.USER_ADD,
            String.format(
                "Aggiunto numero %s", phone.getPhoneNumber()
            )
        );

         */


        return addedPhone;
    }

    public List<Phone> filter(Integer deviceId, String filter, Principal principal) throws UserNotFoundException {
        getUserDetails(principal);

        Optional<User> user = userRepository.findByUsername(userDetails.getUsername());
        if (user.isEmpty()) {
            return List.of();
        }

        StringBuilder filterBuilder = new StringBuilder();

        String join = "";

        if (isSuperUser()) {
            filterBuilder.append("WHERE true ");
        } else if (isDistributor()) {
            filterBuilder.append("join device d on d.id = p.device.id ");
            filterBuilder.append("WHERE d.distributor = :distributor");
        } else if (isUser()) {
            filterBuilder.append("join device d on d.id = p.device.id ");
            filterBuilder.append("join p.device.owner o on o.id = p.device.owner.id ");
            filterBuilder.append("WHERE o.id=:ownerId ");
        } else {
            filterBuilder.append("WHERE false ");
        }

        if (deviceId != null) {
            filterBuilder.append(join).append("and p.device.id=:deviceId ");
        }

        List<String> params = buildFilter(filterBuilder, filter, new String[]{
                "p.phoneNumber",
                "p.description"
        });

        String sql = "SELECT p FROM Phone p " + System.lineSeparator() +
                filterBuilder + System.lineSeparator() +
                " ORDER BY p.description";

        TypedQuery<Phone> query = entityManager.createQuery(sql, Phone.class);
        for (int i = 0; i < params.size(); i++) {
            query.setParameter("param_" + i, params.get(i));
        }

        if (isDistributor()) {
            query.setParameter("distributor", user.get().getDistributor());
        } else if (isUser()) {
            query.setParameter("ownerId", user.get().getId());
        }

        if (deviceId != null) {
            query.setParameter("deviceId", deviceId);
        }

        List<Phone> phones = query.getResultList();
        return phones;

    }

    public Boolean deactivatePhone(Integer phoneId, Principal principal) throws NotFoundException, UserNotFoundException, PermissionDeniedException {
        getUserDetails(principal);

        Optional<User> user = userRepository.findByUsername(userDetails.getUsername());
        if (user.isEmpty()) {
            throw new UserNotFoundException("Utente non trovato");
        }


        Phone phoneToDeactivate = checkDeviceAccessibleToUser(phoneId, user.get());


        Optional<Phone> phone = phoneRepository.findById(phoneId);
        if (phone.isPresent()) {
            phone.get().setActive(false);
            phone.get().setSynched(false);
            phone.get().setModified(true);
            phoneRepository.save(phone.get());
            return true;
        }
        throw new NotFoundException("Telefono non trovato");
    }

    /**
     * Marks the phone for deletion after verifying user access and permissions.
     *
     * @param id The ID of the phone to be deleted.
     * @param principal The security principal of the currently authenticated user.
     * @return A boolean value indicating whether the phone was successfully marked as deleted.
     * @throws UserNotFoundException If the authenticated user could not be found.
     * @throws PermissionDeniedException If the user does not have permission to access the phone.
     * @throws NotFoundException If the phone with the specified ID does not exist.
     */
    public boolean deletePhones(Integer id, Principal principal) throws UserNotFoundException, PermissionDeniedException, NotFoundException {
        getUserDetails(principal);

        Optional<User> user = userRepository.findByUsername(userDetails.getUsername());
        if (user.isEmpty()) {
            throw new UserNotFoundException("Utente non trovato");
        }

        if (phoneRepository.findById(id).isEmpty()) {
            throw new NotFoundException("Telefono non trovato");
        }

        Phone phoneToDelete = checkDeviceAccessibleToUser(id, user.get());

        phoneToDelete.setDeleted(true);
        phoneToDelete.setSynched(false);
        phoneToDelete.setDeletionTime(LocalDateTime.now());
        phoneRepository.save(phoneToDelete);

        return true;

    }


    /**
     * Checks if the device that has the phone is accessible to the given user based on their role and permissions.
     * This method executes a query to retrieve a phone entity based on the user's access level
     * and the provided ID. If the user does not have permission to access the device,
     * a {@link PermissionDeniedException} is thrown.
     *
     * @param id the ID of the phone to be checked.
     * @param user an {@code Optional<User>} representing the current logged-in user requesting access.
     *             The user parameter is required to determine the level of permissions.
     * @return the {@code Phone} entity that the user has access to if permitted.
     * @throws PermissionDeniedException if the user is not allowed to manage the specified phone.
     */
    private Phone checkDeviceAccessibleToUser(Integer id, User user) throws PermissionDeniedException {
        // Check if user has access to phone
        StringBuilder filterBuilder = new StringBuilder();

        String join = "";

        if (isSuperUser()) {
            filterBuilder.append("WHERE phone.id = :id ");
        } else if (isDistributor()) {
            filterBuilder.append("join device d on d.id = phone.device.id ");
            filterBuilder.append("WHERE d.distributor = :distributor and phone.id = :id");
        } else if (isUser()) {
            filterBuilder.append("join device d on d.id = phone.device.id ");
            filterBuilder.append("join phone.device.owner o on o.id = phone.device.owner.id ");
            filterBuilder.append("WHERE o.id=:ownerId and phone.id=:id ");
        } else {
            filterBuilder.append("WHERE false ");
        }

        String sql = "SELECT phone FROM Phone phone " + System.lineSeparator() +
                filterBuilder + System.lineSeparator();

        TypedQuery<Phone> query = entityManager.createQuery(sql, Phone.class);
        query.setParameter("id", id);

        if (isDistributor()) {
            query.setParameter("distributor", user.getDistributor());
        } else if (isUser()) {
            query.setParameter("ownerId", user.getId());
        }

        List<Phone> phones = query.getResultList();
        if (phones.isEmpty()) {
            throw new PermissionDeniedException("Utente non autorizzato a gestire il telefono specificato");
        }
        return phones.getFirst();
    }

    public Boolean activatePhone(Integer phoneId, Principal principal) throws NotFoundException, UserNotFoundException, PermissionDeniedException {
        getUserDetails(principal);

        Optional<User> user = userRepository.findByUsername(userDetails.getUsername());
        if (user.isEmpty()) {
            throw new UserNotFoundException("Utente non trovato");
        }

        if (phoneRepository.findById(phoneId).isEmpty()) {
            throw new NotFoundException("Telefono non trovato");
        }

        Phone phone = checkDeviceAccessibleToUser(phoneId, user.get());

        phone.setActive(true);
        phoneRepository.save(phone);
        return true;
    }

    public List<Phone> getDeletedPhones(Device device) {
        return phoneRepository.findDeletedPhoneByDevice(device.getId());
    }

    public List<Phone> getModifiedPhones(Device device) {
        return phoneRepository.findModifiedPhoneByDevice(device.getId());
    }

    public void delete(Integer id) {
        phoneRepository.deleteById(id);
    }

    public void clearUserModifiedFlags(Integer id) {
        phoneRepository.clearUserModifiedFlags(id);
    }

}