package com.vaessl.app.connection;

import java.time.Instant;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

import org.springframework.stereotype.Service;

import com.vaessl.app.dto.ConnectionRequest;
import com.vaessl.app.dto.ConnectionResponse;
import com.vaessl.app.dto.ConnectionStatusResponse;
import com.vaessl.app.dto.LoginResult;
import com.vaessl.app.exception.WrongServiceTypeException;

@Service
public class ConnectionService {

    private final Map<String, ConnectionProvider> providerRegistry;

    private final ConnectionRepository cRepository;

    public ConnectionService(List<ConnectionProvider> providers, ConnectionRepository cRepository) {
        this.providerRegistry = providers.stream()
                .collect(Collectors.toMap(ConnectionProvider::getServiceType, p -> p));
        this.cRepository = cRepository;
    }

    public LoginResult login(ConnectionRequest request) {

        ConnectionProvider provider = providerRegistry.get(request.serviceType());

        if (provider == null) {
            throw new WrongServiceTypeException();
        }

        provider.checkCredentials(request);

        ConnectionResponse response = provider.authenticate(request);

        ConnectionEntity existing = provider.findUniqueConnectionEntry(request);

        ConnectionEntity saved;
        if (existing != null) {
            provider.updateToRepository(existing, response);
            saved = existing;
        } else {
            ConnectionEntity newEntity = provider.connectionToEntity(request, response);
            saved = cRepository.save(newEntity);
        }

        return new LoginResult(saved.getId(), response.expiresAt());
    }

    public ConnectionStatusResponse getConnectionStatus(String serviceType, Long connectionId) {
        ConnectionEntity entity = cRepository.findById(connectionId).orElse(null);
        if (entity == null) return null;

        ConnectionProvider provider = providerRegistry.get(serviceType);
        Instant expiresAt = (provider != null) ? provider.getTokenExpiry(entity) : null;
        boolean connected = expiresAt == null || expiresAt.isAfter(Instant.now());

        return new ConnectionStatusResponse(serviceType, entity.getAppUrl(),
                entity.getUsername(), expiresAt, connected);
    }
}