添加单实例管理器

[Soar360]

单实例互斥 + 通过命名管道激活已有窗口。

• 补充文档
• 修改全局锁的名称
• 补充单元测试？（可选）

using System.IO.Pipes;
using System.Security.Cryptography;
using System.Text;

namespace Popcorn.Toolkit.Libs;

public static class SingleInstanceManager
{
    private const string Command_ActivateWindow = "ActivateWindow";
    private static Mutex? _processLock;
    private static bool _hasLock;

    public static event EventHandler? ActivateWindowRequested;

    /// <summary>
    /// 获取进程锁
    /// </summary>
    public static void EnsureSingleInstance()
    {
        // 全局锁，锁名称可以自定义。
        string key = $"Global\\Popcorn.Toolkit[{GetUid()}]";
        _processLock = new Mutex(false, key, out _hasLock);
        if (_hasLock)
        {
            Task.Factory.StartNew(() => ServerThread(key), TaskCreationOptions.LongRunning);
        }
        else
        {
            RequestActivateWindow(key);
            Environment.Exit(0);
        }
    }


    private static string GetUid()
    {
        var bytes = Encoding.UTF8.GetBytes(Environment.ProcessPath ?? AppContext.BaseDirectory);
        using (var md5 = MD5.Create())
        {
            bytes = md5.ComputeHash(bytes);
        }

        return BitConverter.ToString(bytes).Replace("-", "").ToLowerInvariant();
    }


    /// <summary>
    /// 释放当前进程的锁
    /// </summary>
    /// <remarks>小心使用</remarks>
    public static void ReleaseLock()
    {
        if (_processLock != null && _hasLock)
        {
            _processLock.Dispose();
            _hasLock = false;
        }
    }

    private static async Task ServerThread(string name)
    {
        while (true)
        {
            using (var server = new NamedPipeServerStream(name))
            {
                await server.WaitForConnectionAsync();
                using (var reader = new StreamReader(server))
                {
                    var command = await reader.ReadLineAsync();
                    if (command == Command_ActivateWindow)
                    {
                        ActivateWindowRequested?.Invoke(null, EventArgs.Empty);
                    }
                }
            }
        }
    }

    private static void RequestActivateWindow(string key)
    {
        using (var client = new NamedPipeClientStream(key))
        {
            client.Connect(1000);
            using (var writer = new StreamWriter(client))
            {
                writer.WriteLine(Command_ActivateWindow);
                writer.Flush();
            }
        }
    }
}