using System;
using System.Collections.Generic;
using System.Text;
using System.Threading.Tasks;
using MQTTnet;
using MQTTnet.Client;
using MQTTnet.Extensions.ManagedClient;
using NLog.Fluent;

namespace Dfs.WayneChina.CheryFuelController
{
    public class CheryClient
    {
        private readonly string _host;
        private readonly int _port;
        private readonly string _clientId;
        private readonly int _interval;
        private readonly string _jobDownUrl;
        private readonly string _jobResUpUrl;

        private IManagedMqttClient _mqttClient;

        #region Logger

        NLog.Logger logger = NLog.LogManager.LoadConfiguration("NLog.config").GetLogger("Application");

        #endregion

        public CheryClient(string host, int port, string clientId, string username, string password,
            int interval, string jobDownUrl, string jobResultUpUrl)
        {
            _host = host;
            _port = port;
            _clientId = clientId;
            _interval = interval;
            _jobDownUrl = jobDownUrl;
            _jobResUpUrl = jobResultUpUrl;

            _mqttClient = new MqttFactory().CreateManagedMqttClient();

            _mqttClient.ConnectedAsync += this.OnConnected;
            _mqttClient.DisconnectedAsync += this.OnDisconnected;
            _mqttClient.ConnectingFailedAsync += this.OnConnectingFailed;
            _mqttClient.ApplicationMessageReceivedAsync += this.HandleApplicationMessageReceivedAsync;
        }

        public Task HandleApplicationMessageReceivedAsync(MqttApplicationMessageReceivedEventArgs eventArgs)
        {
            string topic = $"Topic: {eventArgs.ApplicationMessage.Topic}";
            string payload = $"- Payload: {System.Text.Encoding.UTF8.GetString(eventArgs.ApplicationMessage.Payload)}";
            logger.Info($"Received: {topic + payload}");

            return Task.CompletedTask;
        }

        private ManagedMqttClientOptions CreateOptions(string host, int port, string clientId)
        {
            MqttClientOptionsBuilder builder = new MqttClientOptionsBuilder()
                //.WithClientId(clientId)
                .WithTcpServer(host, port);

            ManagedMqttClientOptions options = new ManagedMqttClientOptionsBuilder()
                .WithAutoReconnectDelay(TimeSpan.FromSeconds(_interval))
                .WithClientOptions(builder.Build())
                .Build();

            return options;
        }

        public async Task StartAsync()
        {
            var options = CreateOptions(_host, _port, _clientId);
            await _mqttClient.StartAsync(options);

            string topic = "test/downFillSet";
            await _mqttClient.SubscribeAsync(new[] { new MqttTopicFilterBuilder().WithTopic(topic).Build() });
        }

        public Task StopAsync()
        {
            return _mqttClient.StopAsync();
        }

        public Task OnConnected(MqttClientConnectedEventArgs obj)
        {
            logger.Info($"Successfully connected to Broker, assigned id: {obj.ConnectResult.AssignedClientIdentifier}");
            return Task.CompletedTask;
        }

        public Task OnConnectingFailed(ConnectingFailedEventArgs obj)
        {
            logger.Error($"Couldn't connect to broker, {obj.Exception}");
            return Task.CompletedTask;
        }

        public Task OnDisconnected(MqttClientDisconnectedEventArgs obj)
        {
            logger.Error("Successfully disconnected.");
            return Task.CompletedTask;
        }
    }
}