using System.Collections.Concurrent;
using System.Net.NetworkInformation;

namespace WCS.Core;

public class PLC : EntityEx<PLCInfo>
{
    public PLC(PLCInfo ent, World world) : base(ent)
    {
        if (Configs.PLCAccessorCreater != null) Accessor = Configs.PLCAccessorCreater.Create(ent);
        else throw new Exception("Configs.PLCAccessorCreater未赋值");

        IPDetection.AddIP(Entity.IP);
    }

    public bool Ping { get => IPDetection.GetIpStatus(Entity.IP); }

    public IPLCAccessor Accessor { get; private set; }
}

public class IPDetection
{
    /// <summary>
    ///  需要检测的IP组，使用线程安全的字典
    /// </summary>
    private static ConcurrentDictionary<string, bool> _ipDetection = new ConcurrentDictionary<string, bool>();

    /// <summary>
    ///  是否启动检测器
    /// </summary>
    private static bool isStart = false;

    /// <summary>
    /// 取消标记，用于停止检测任务
    /// </summary>
    private static CancellationTokenSource cancellationTokenSource;

    /// <summary>
    /// 添加IP进行检测
    /// </summary>
    /// <param name="ip"></param>
    public static void AddIP(string ip)
    {
        if (!_ipDetection.ContainsKey(ip))
        {
            _ipDetection[ip] = false; // 默认为不在线
        }

        if (!isStart)
        {
            isStart = true;
            Start();
        }
    }

    /// <summary>
    /// 获取指定IP的状态
    /// </summary>
    /// <param name="ip"></param>
    /// <returns></returns>
    public static bool GetIpStatus(string ip)
    {
        return _ipDetection.ContainsKey(ip) && _ipDetection[ip];
    }

    /// <summary>
    /// 启动IP检测任务
    /// </summary>
    private static void Start()
    {
        cancellationTokenSource = new CancellationTokenSource();
        Task.Run(async () =>
        {
            while (!cancellationTokenSource.Token.IsCancellationRequested)
            {
                await CheckIpsAsync();
                await Task.Delay(1000); // 等待 1 秒
            }
        }, cancellationTokenSource.Token);
    }

    /// <summary>
    /// 停止IP检测任务
    /// </summary>
    public static void Stop()
    {
        cancellationTokenSource?.Cancel();
        isStart = false;
    }

    /// <summary>
    /// 检测所有IP的状态
    /// </summary>
    /// <returns></returns>
    private static async Task CheckIpsAsync()
    {
        var tasks = new List<Task>();

        foreach (var ip in _ipDetection.Keys.ToList()) // 使用 ToList 防止遍历时修改字典
        {
            tasks.Add(Task.Run(async () =>
            {
                bool isOnline = await PingAsync(ip);
                _ipDetection[ip] = isOnline;
            }));
        }

        await Task.WhenAll(tasks);
    }

    /// <summary>
    /// pingIp
    /// </summary>
    /// <param name="ip"></param>
    /// <returns></returns>
    private static async Task<bool> PingAsync(string ip)
    {
        try
        {
            if (ip == "1") return false;
            Ping ping = new Ping();
            PingReply reply = await ping.SendPingAsync(ip, 300); // 设置超时时间为300毫秒
            return reply.Status == IPStatus.Success;
        }
        catch
        {
            // 如果出现异常，认为该IP不可用
            return false;
        }
    }
}

public interface IPLCAccessorCreater
{
    IPLCAccessor Create(PLCInfo data);
}

public interface IPLCAccessor
{
    void WriteBytes(ushort db, ushort address, byte[] data);

    byte[] ReadBytes(ushort db, ushort address, ushort length);
}