using MasstransferCommon.Utils;
using MasstransferInfrastructure.Mqtt.Model;
using MQTTnet;
using MQTTnet.Client;
using MQTTnet.Protocol;
using Serilog;

namespace MasstransferInfrastructure.Mqtt.Client;

public class MessageQueueHelper<T>
{
    private static readonly Dictionary<string, List<Action<string, T>>> Subscribers = new();

    // ReSharper disable once StaticMemberInGenericType
    private static readonly MqttClient Client = new();


    /// <summary>
    /// 初始化连接
    /// </summary>
    /// <param name="options"></param>
    public static async Task<bool> InitConnect(MqttConnectOptions options)
    {
        try
        {
            if (!await Client.ConnectAsync(options)) return false;
            // 连接成功后监听消息
            Client.MessageReceived += HandleMessageReceived;
            return true;
        }
        catch (Exception e)
        {
            Log.Error(e, "连接MQTT服务器失败");
            return false;
        }
    }

    /// <summary>
    ///  订阅某个主题
    /// </summary>
    /// <param name="topic"></param>
    /// <param name="delegate"></param>
    /// <param name="qos"></param>
    public static async Task<bool> Subscribe(string topic, Action<string, T> @delegate,
        MqttQualityOfServiceLevel qos = MqttQualityOfServiceLevel.AtMostOnce)
    {
        if (!Subscribers.ContainsKey(topic))
        {
            Subscribers.Add(topic, []);
        }

        Subscribers[topic].Add(@delegate);

        return await Client.Subscribe(topic, qos);
    }

    /// <summary>
    /// 发送消息
    /// </summary>
    /// <param name="topic"></param>
    /// <param name="message"></param>
    /// <param name="qos"></param>
    public static async Task<bool> Publish(string topic, object message,
        MqttQualityOfServiceLevel qos = MqttQualityOfServiceLevel.AtMostOnce)
    {
        return await Client.Publish(topic, message, qos);
    }

    /// <summary>
    /// 处理接收到的消息
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    /// <returns></returns>
    private static void HandleMessageReceived(object? sender, MqttApplicationMessageReceivedEventArgs e)
    {
        var applicationMessage = e.ApplicationMessage;
        var topic = applicationMessage.Topic;
        var message = applicationMessage.ConvertPayloadToString();

        if (!Subscribers.TryGetValue(topic, out var subscribers)) return;

        foreach (var subscriber in subscribers)
        {
            try
            {
                // 通知订阅者
                subscriber(topic, JsonUtil.FromJson<T>(message));
            }
            catch (Exception exception)
            {
                Log.Error(exception, "订阅主题 {Topic} 时发生错误", topic);
            }
        }
    }
}