using MQTTnet;
using MQTTnet.Client;
using Microsoft.Extensions.Options;
using Microsoft.Extensions.Logging;
using System.Text;
using MQTTnet.Server;


namespace Fuel.Application.MqttService
{
    public class MqttClientService : IMqttClientService, IDisposable
    {
        private  IMqttClient _mqttClient;
        private  MqttOptions _options;
        private  ILogger<MqttClientService> _logger;
        private bool _disposed = false;

        public MqttClientService(
            IOptions<MqttOptions> options,
            ILogger<MqttClientService> logger)
        {
            _options = options.Value;
            _logger = logger;

            var factory = new MqttFactory();
            _mqttClient = factory.CreateMqttClient();

            // 配置事件处理
            _mqttClient.ConnectedAsync += HandleConnectedAsync;
            _mqttClient.DisconnectedAsync += HandleDisconnectedAsync;
            _mqttClient.ApplicationMessageReceivedAsync += HandleMessageReceivedAsync;
        }

        private async Task HandleConnectedAsync(MqttClientConnectedEventArgs e)
        {
            _logger.LogInformation("MQTT connected");
            await Task.CompletedTask;
        }

        private async Task HandleDisconnectedAsync(MqttClientDisconnectedEventArgs e)
        {
            _logger.LogWarning("MQTT disconnected. Attempting to reconnect...");
            await Task.Delay(TimeSpan.FromSeconds(5));
            if (!_disposed)
            {
                await ConnectAsync(); // 自动重连
            }
        }

        private async Task HandleMessageReceivedAsync(MqttApplicationMessageReceivedEventArgs e)
        {
            var payload = Encoding.UTF8.GetString(e.ApplicationMessage.Payload);
            _logger.LogInformation($"Received message: {payload} [Topic: {e.ApplicationMessage.Topic}]");
            await Task.CompletedTask;
        }

        public async Task ConnectAsync()
        {
            if (_mqttClient.IsConnected)
            {
                return;
            }

            var options = new MqttClientOptionsBuilder()
                .WithTcpServer(_options.Server, _options.Port)
                .WithClientId(_options.ClientId)
                .WithCredentials("HSClient", "HS202503")
                .WithCleanSession()
                .Build();

            try
            {
                await _mqttClient.ConnectAsync(options);
            }
            catch (ObjectDisposedException ex)
            {
                _logger.LogError($"Error connecting to MQTT broker: {ex.Message}");
                // 处理异常或重新创建客户端实例
            }
        }

        public async Task PublishAsync(string topic, string payload)
        {
            if (!_mqttClient.IsConnected)
            {
                await ConnectAsync();
            }

            var message = new MqttApplicationMessageBuilder()
                .WithTopic(topic)
                .WithPayload(payload)
                .WithQualityOfServiceLevel(MQTTnet.Protocol.MqttQualityOfServiceLevel.AtLeastOnce)
                .Build();

            try
            {
                await _mqttClient.PublishAsync(message);
            }
            catch (ObjectDisposedException ex)
            {
                _logger.LogError($"Error publishing message: {ex.Message}");
                // 处理异常或重新创建客户端实例
            }
        }

        public async Task SubscribeAsync(string topic)
        {
            if (!_mqttClient.IsConnected)
            {
                await ConnectAsync();
            }

            var topicFilter = new MqttTopicFilterBuilder()
                .WithTopic(topic)
                .Build();

            try
            {
                await _mqttClient.SubscribeAsync(topicFilter);
            }
            catch (Exception ex)
            {
                _logger.LogError($"Error subscribing to topic {topic}: {ex.Message}");
                // 处理异常
            }
        }

        public async Task DisconnectAsync()
        {
            if (_mqttClient.IsConnected)
            {
                await _mqttClient.DisconnectAsync();
            }
        }

        protected virtual void Dispose(bool disposing)
        {
            if (!_disposed)
            {
                if (disposing)
                {
                    _mqttClient?.Dispose();
                }

                _disposed = true;
            }
        }

        public void Dispose()
        {
            Dispose(true);
            GC.SuppressFinalize(this);
        }
    }
}