using Godot;
using System;
using System.Threading;
using BITKit.Packages.Core.LazyLoad;

namespace BITKit;
public partial class HttpGet : Node,IActivable
{
    /// <summary>
    /// 访问的Url
    /// </summary>
    [Export] private string url;
    /// <summary>
    /// 是否启用
    /// </summary>
    [Export]
    public bool Enabled { get; set; } = true;
    [Signal]
    public delegate void OnGetEventHandler(string httpContext);
    /// <summary>
    /// 最大并行请求数量
    /// </summary>
    private readonly LimitTimes limitConcurrent =new (1);
    /// <summary>
    /// 请求数据的间隔
    /// </summary>
    private readonly IntervalTimer _intervalTimer = new(1);
    /// <summary>
    /// http客户端
    /// </summary>
    private readonly ServiceLoader<System.Net.Http.HttpClient>  httpClient=new();
    /// <summary>
    /// 取消令牌，用于取消Http Get
    /// </summary>
    private CancellationToken _cancellationToken;

    public override void _Ready()
    {
        _cancellationToken = new CancellationToken();
    }
    /// <summary>
    /// 物理帧用于控制并发和间隔的同时请求数据
    /// </summary>
    /// <param name="delta"></param>
    public override void _PhysicsProcess(double delta)
    {
        if(Enabled is false)return;
        //等待依赖加载
        //请求间隔控制+请求并发控制
        if (_intervalTimer.Allow is false || httpClient.IsLoaded is false) return;
        //如果url为空
        if (string.IsNullOrEmpty(url)) return;
        if (!limitConcurrent.AllowOnly) return;
        //提交并发
        limitConcurrent.CanUpdate();
        //发送请求
        Request();
    }
    private async void Request()
    {
        //获取json

        try
        {
            var json = await httpClient.Value.GetStringAsync(url, _cancellationToken);
            //取消执行，如果已取消令牌
            _cancellationToken.ThrowIfCancellationRequested();

            //调用回调
            EmitSignal(nameof(OnGet), json);
        }
        catch (InvalidOperationException)
        {
            BIT4Log.Warning(url);
            //返回并发数量
            limitConcurrent.Release();
        }
        catch (OperationCanceledException)
        {
            //返回并发数量
            limitConcurrent.Release();
        }
    }

    public void SetActive(bool active) => Enabled=active;
   
}