FieldWorkClient/ViewModel/Send/DownViewModel.cs

using System.Collections.Concurrent;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Diagnostics;
using System.Windows;
using System.Windows.Data;
using System.Windows.Input;
using HeBianGu.Base.WpfBase;
using HeBianGu.Service.Mvc;
using Hopetry.Models;
using Hopetry.Provider;
using Hopetry.Services;
using Newtonsoft.Json;

namespace Hopetry.ViewModel.Send;

[ViewModel("Down")]
public class DownViewModel : MvcViewModelBase
{
    private readonly MinioService _minioService;

    public RelayCommand<MinioDownloadTask> OpenDownItemFolder { get; set; }
    private readonly ConcurrentQueue<MinioDownloadTask> _taskQueue = new();
    private SemaphoreSlim _semaphore;

    private CancellationTokenSource _processingCts = new();
    public int count { get; set; }
    private readonly ReaderWriterLockSlim _lock = new();

    private Visibility _tab0Visibility;

    public Visibility Tab0Visibility
    {
        get => _tab0Visibility;
        set
        {
            _tab0Visibility = value;
            RaisePropertyChanged();
        }
    }

    private Visibility _tab1Visibility;

    public Visibility Tab1Visibility
    {
        get => _tab1Visibility;
        set
        {
            _tab1Visibility = value;
            RaisePropertyChanged();
        }
    }

    private int _tabIndex;

    public int TabIndex
    {
        get => _tabIndex;
        set
        {
            _tabIndex = value;
            if (_tabIndex == 0)
            {
                Tab0Visibility = Visibility.Visible;
                Tab1Visibility = Visibility.Hidden;
            }
            else if (_tabIndex == 1)
            {
                Tab0Visibility = Visibility.Hidden;
                Tab1Visibility = Visibility.Visible;
            }

            RaisePropertyChanged();
        }
    }

    /// <summary>
    /// 全部任务动态标题
    /// </summary>
    private string _allTaskHeader;

    public string AllTaskHeader
    {
        get => _allTaskHeader;
        set
        {
            _allTaskHeader = value;
            RaisePropertyChanged();
        }
    }

    private string _runningTaskHeader;

    public string RunningTaskHeader
    {
        get => _runningTaskHeader;
        set
        {
            _runningTaskHeader = value;
            RaisePropertyChanged();
        }
    }

    private string _finishedTaskHeader;

    public string FinishedTaskHeader
    {
        get => _finishedTaskHeader;
        set
        {
            _finishedTaskHeader = value;
            RaisePropertyChanged();
        }
    }

    // 绑定属性
    //public ObservableCollection<MinioDownloadTask> AllTasks { get; set; }
    private ObservableCollection<MinioDownloadTask> _runningTasks;

    public ObservableCollection<MinioDownloadTask> RunningTasks
    {
        get => _runningTasks;
        set
        {
            _runningTasks = value;
            RaisePropertyChanged(); // 触发INotifyPropertyChanged通知
        }
    }

    private ObservableCollection<MinioDownloadTask> _finishedTasks;
    public ObservableCollection<MinioDownloadTask> FinishedTasks
    {
        get => _finishedTasks;
        set
        {
            _finishedTasks = value;
            RaisePropertyChanged(); // 触发INotifyPropertyChanged通知
        }
    }
    private int _maxConcurrent = 3;

    public int MaxConcurrent
    {
        get => _maxConcurrent;
        set
        {
            if (value < 1) value = 1;
            if (_maxConcurrent == value) return;

            _maxConcurrent = value;
            //AdjustConcurrency();
            RaisePropertyChanged();
        }
    }

    public ICommand ClearFinishedCommand { get; }


    /// <summary>
    /// 构造函数
    /// </summary>
    /// <param name="minioService"></param>
    public DownViewModel(MinioService minioService)
    {
        _minioService = minioService;
        Console.WriteLine("初始化DownViewModel");
        using var client = SqlSugarConfig.GetSqlSugarScope();
        OpenDownItemFolder = new RelayCommand<MinioDownloadTask>(DoOpenDownItemFolder);
        LoadFinishedTasks();
        LoadRunningTasks();
        ClearFinishedCommand = new CustomCommand(DoClearFinishedCommand);
        // 启动任务处理线程
        _semaphore = new SemaphoreSlim(MaxConcurrent);
        new Thread(ProcessTasksLoop) { IsBackground = true }.Start();
    }

    private void DoClearFinishedCommand()
    {
        using var client = SqlSugarConfig.GetSqlSugarScope();
        client.Deleteable<MinioDownloadTask>().Where(x => x.Status == "已完成").ExecuteCommand();
        FinishedTasks.Clear();
        FinishedTaskHeader = $"已完成（0）";
    }

    public void LoadRunningTasks()
    {
        using var client = SqlSugarConfig.GetSqlSugarScope();
        var data = client.Ado
            .SqlQuery<MinioDownloadTask>(
                $"select * from download_task where status='下载中' or status='等待中' or status='已暂停' order by task_id desc");
        RunningTasks = new ObservableCollection<MinioDownloadTask>(data);
        RunningTaskHeader = $"下载中（{RunningTasks.Count}）";
    }

    public void LoadFinishedTasks()
    {
        using var client = SqlSugarConfig.GetSqlSugarScope();
        var data = client.Ado
            .SqlQuery<MinioDownloadTask>($"select * from download_task where status='已完成' order by datetime(finished_time) desc");
        FinishedTasks = new ObservableCollection<MinioDownloadTask>(data);
        FinishedTaskHeader = $"已完成（{FinishedTasks.Count}）";
    }

    private async void ProcessTasksLoop()
    {
        int c1 = 1;
        while (!_processingCts.IsCancellationRequested)
        {
            if (_taskQueue.TryDequeue(out var task))
            {
                Console.WriteLine("存在可下载任务，正在申请许可...");
                await _semaphore.WaitAsync();
                Console.WriteLine("申请下载许可成功！马上开启下载");
                // 启动新线程执行下载任务
                // _ = Task.Run(() => ExecuteTaskAsync(task));
                _ = ExecuteTaskAsync(task).ContinueWith(_ => _semaphore.Release());
            }

            // 无任务时，进入低功耗轮询
            Thread.Sleep(500);
        }
    }

    public void AddTask(string bucketName, string objectKey, string size)
    {
        var downDir = ViewModelLocator.SyncViewModel.SyncDir;
        var task = new MinioDownloadTask(_minioService, bucketName, objectKey, downDir, size);
        using var client = SqlSugarConfig.GetSqlSugarScope();
        client.Insertable(task).ExecuteCommandIdentityIntoEntity();
        LoadFinishedTasks();
        LoadRunningTasks();
        Console.WriteLine($"文件大小：{size} ");
        _taskQueue.Enqueue(task);
    }


    private async Task ExecuteTaskAsync(MinioDownloadTask task)
    {
        try
        {
            // todo 下载失败3次，停止下载
            await task.StartDownload();
            LoadRunningTasks();
            LoadFinishedTasks();
            Console.WriteLine($"异步下载完成：{task.FileName}");
        }
        finally
        {
        }
    }

    private void AdjustConcurrency()
    {
        lock (_semaphore)
        {
            // 调整信号量容量
            var delta = _maxConcurrent - _semaphore.CurrentCount;
            if (delta > 0)
            {
                for (int i = 0; i < delta; i++)
                {
                    _semaphore.Release();
                }
            }
        }
    }

    public void DoOpenDownItemFolder(MinioDownloadTask para)
    {
        Console.WriteLine($"点击item值：{JsonConvert.SerializeObject(para)}");
        Process.Start("explorer.exe", para.FilePath);
    }

    public void DoCancelDownItem(MinioDownloadTask item)
    {
        Console.WriteLine("取消下载");
        // todo 实现取消下载
    }

    public void DoPauseDownItem(MinioDownloadTask item)
    {
        Console.WriteLine("暂停下载");
        // todo 实现暂停下载
    }

    protected override void Init()
    {
    }

    protected override void Loaded(string args)
    {
    }
}