using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Diagnostics.Tracing;
using System.Timers;
using Cysharp.Threading.Tasks;
using kcp2k;
using Timer = System.Timers.Timer;
using System.Threading.Tasks;
using System.IO;
using System.Linq;
using System.Net;
using System.Numerics;
using System.Reflection;
using System.Text;
using System.Threading;
using BITKit.Net.Examples;
using Microsoft.Extensions.Logging;
using Newtonsoft.Json;
using Unity.Mathematics;

namespace BITKit.Net
{
    public class KcpNetClient:INetClient,INetProvider
    {
        private readonly NetProviderCommon _common = new();
        private readonly ILogger<KcpNetClient> _logger;
        public KcpNetClient(ILogger<KcpNetClient> logger)
        {
            _logger = logger;
            _client = new KcpClient(
                OnConnectedInternal,
                OnData,
                OnDisconnectInternal,
                OnError,
                KCPNet.Config
            );
            _timer.Elapsed += Tick;
            _logger.LogInformation("已创建KCP客户端");
            _isConnected.AddListener(ConnectionCallback);
        }
        
        public event Action OnStartConnect;
        public event Action OnConnected;
        public event Action OnDisconnected;
        public event Action OnConnectedFailed;
        public uint TickRate { get; set; } = 8;
        public bool IsConnected => _isConnected;
        public bool IsConnecting { get; private set; }
        public bool AutoReconnect { get; set; } = true;
        public float2 Traffic { get; private set; }
        public bool ManualTick { get; set; }
        
        private readonly IntervalUpdate _reconnectInterval = new(1);
 
        public int Ping { get; private set; }
        public int Id { get; private set; } = -1;
        private readonly KcpClient _client;

        private readonly ConcurrentQueue<byte[]> _commandQueue = new();
        
        private DateTime _lastPingTime = DateTime.Now;
        
        private readonly Timer _timer = new(100)
        {
            AutoReset = true
        };


        private readonly ValidHandle _isConnected = new();
        private bool _userConnected;
        private int _index = int.MinValue;
        
        private DateTime _now = DateTime.Now;
        private TimeSpan _interval = TimeSpan.FromMilliseconds(100);
        private string _connectedAddress = "127.0.0.1";
        private ushort _connectedPort = 27014;

        private async void ConnectionCallback(bool x)
        {
            await BITApp.SwitchToMainThread();
            if (x)
            {
                OnConnected?.Invoke();
                 _logger.LogInformation("连接成功");
            }
            else
            {
                OnDisconnected?.Invoke();
                 _logger.LogInformation("连接已断开");
            }
        }

        private void Tick(object sender, ElapsedEventArgs e)
        {
            if (!ManualTick)
                Tick();
        }

        public async void Disconnect()
        {
            _userConnected = false;
            DisconnectInternal();
        }
        private async void DisconnectInternal()
        {
            IsConnecting = false;
            _client.Disconnect();
            _isConnected.RemoveElement(this);
            _timer.Stop();
            try
            {
                await BITApp.SwitchToMainThread();
                OnDisconnected?.Invoke();
            }
            catch (OperationCanceledException){}
        }

        private string _lastHostName;
        public async UniTask<bool> Connect(string address = "127.0.0.1", ushort port = 27014)
        {
            if (IsConnecting)
            {
                _logger.LogWarning("正在连接中");
                return false;
            }
            _userConnected = true;
            
            //如果address是域名,解析为Ip
            if (address.Contains("."))
            {
                var ip = await Dns.GetHostAddressesAsync(address);
                if (ip.Length > 0)
                {
                    address = ip[0].ToString();
                    if (_lastHostName != address)
                    {
                        _logger.LogInformation($"解析域名:{address},IP:{ip}");
                        _lastHostName = address;
                    }
                }
            }

            if (address is not "127.0.0.1")
                _connectedAddress = address;
            if (port is not 27014)
                _connectedPort = port;
            
            
            IsConnecting = true;
            if (_client.connected) return false;
            await BITApp.SwitchToMainThread();
            OnStartConnect?.Invoke();
            await UniTask.SwitchToThreadPool();
            try
            {
                _common.LastHeartbeat.GetOrCreate(0);
                _common.LastHeartbeat[0] = DateTime.Now;
                
                    _client.Connect(address, port);
          
                _timer.Start();
                _interval = TimeSpan.FromMilliseconds(_timer.Interval);

                    if (_client.connected)
                    {
                        HandShake();
                        _client.Send(new[] { (byte)NetCommandType.Heartbeat }, KcpChannel.Reliable);
                        Traffic += new float2(1, 0);
                    }
                    _client.Tick();
                    await Task.Delay(100);

                if (_client.connected)
                {
                    SendServerMessage(Environment.MachineName);
                    
                    IsConnecting = false;
                    
                    _connectedAddress = address;
                    _connectedPort = port;

             
                    
                    return _client.connected;
                }

                OnConnectedFailed?.Invoke();
                DisconnectInternal();

                IsConnecting = false;
                return false;
            }
            catch (Exception e)
            {
                _logger.LogCritical(e,e.Message);
                if (BITApp.SynchronizationContext is not null)
                    await UniTask.SwitchToSynchronizationContext(BITApp.SynchronizationContext);
                OnConnectedFailed?.Invoke();
                _timer.Stop();
                
                IsConnecting = false;
                return false;
            }
        }

        private void OnData(ArraySegment<byte> bytes, KcpChannel channel)
        {
            try
            {
                Traffic+=new float2(0,bytes.Count);
                OnDataInternal(bytes, channel);
            }
            catch (Exception e)
            {
                _logger.LogCritical(e,e.Message);
            }
        }
        private void OnDataInternal(ArraySegment<byte> bytes, KcpChannel channel)
        {
            try
            {
                _common.OnDataInternal(0,bytes,channel);
            }
            catch (Exception e)
            {
                _logger.LogCritical(e,e.Message);
            }
          
        }

        private async void OnConnectedInternal()
        {
         
        }

        private async  void OnDisconnectInternal()
        {
            DisconnectInternal();
        }
        private void OnError(ErrorCode errorCode, string message)
        {
             _logger.LogInformation($"{_client.remoteEndPoint}异常:{errorCode},{message}");
        }
        

        public void SendServerMessage(string message)
        {
            var bytes = BinaryBuilder
                .Create()
                .Write(((byte)NetCommandType.Message))
                .Write(message)
                .Build();
            Traffic+=new float2(bytes.Length,0);
            _client.Send(bytes, KcpChannel.Reliable);
        }

        public void Tick()
        {
            _now = DateTime.Now;
            if(_userConnected is false)return;
            try
            {
                if (_client.connected)
                {
                    if (DateTime.Now - _common.LastHeartbeat.GetOrCreate(0) > TimeSpan.FromSeconds(5))
                    {
                        _logger.LogWarning("心跳超时,自动断开");
                        DisconnectInternal();
                        _commandQueue.Clear();
                        return;
                    }
                    while (_commandQueue.TryDequeue(out var bytes))
                    {
                        Traffic += new float2(bytes.Length, 0);
                        _client.Send(bytes, KcpChannel.Reliable);
                    }
                    Traffic+=new float2(1,0);
                    _client.Send(_common.HeartBeat, KcpChannel.Unreliable);
                }
                else
                {
                    if (AutoReconnect && _reconnectInterval.AllowUpdate)
                    {
                        if (IsConnecting is false)
                        {
                            Connect(_connectedAddress,_connectedPort).Forget();
                        }
                    }
                    if (_commandQueue.Count > 0)
                    {
                        _commandQueue.Clear();
                        //BIT4Log.Warning<KcpNetClient>("连接已断开,清空指令队列");
                    }
                }
                _client.Tick();
            }
            catch (Exception e)
            {
             _logger.LogCritical(e,e.Message);
            }

        }

        public void HandShake()
        {
            // send client to server
            Traffic+=new float2(2,0);
            _client.Send(new byte[]{0x01, 0x02}, KcpChannel.Reliable);
        }
        public T GetRemoteInterface<T>() => _common.GetRemoteInterface<T>();
        public void Invoke(Memory<byte> bytes)
        {
            throw new NotImplementedException();
        }

        public UniTask<Memory<byte>> InvokeAsync(Memory<byte> bytes)
        {
            throw new NotImplementedException();
        }

        public void Invoke(IReadOnlyList<byte> bytes)
        {
            throw new NotImplementedException();
        }

        public UniTask<IReadOnlyList<byte>> InvokeAsync(IReadOnlyList<byte> bytes)
        {
            throw new NotImplementedException();
        }
    }
}