using System;
using System.Diagnostics;
using System.IO.Pipes;
using System.Text;
using System.Text.Json;
using System.Threading;
using Notify.Serialization;

namespace Notify.Ipc;

/// <summary>
/// 瘦客户端侧：把一条 PipeMessage 发给 Host，Host 不在则拉起后重试
/// </summary>
public static class PipeClient
{
    public static bool Send(PipeMessage message)
    {
        var json = JsonSerializer.Serialize(message, AppJsonContext.Default.PipeMessage);
        var bytes = Encoding.UTF8.GetBytes(json);

        if (TrySend(bytes, 300))
        {
            return true;
        }

        // Host 未运行：拉起后等待其管道就绪再重试，最多约 5 秒
        StartHost();
        for (var i = 0; i < 50; i++)
        {
            Thread.Sleep(100);
            if (TrySend(bytes, 300))
            {
                return true;
            }
        }

        return false;
    }

    private static bool TrySend(byte[] bytes, int timeoutMs)
    {
        try
        {
            using var client = new NamedPipeClientStream(".", IpcConstants.PipeName, PipeDirection.Out);
            client.Connect(timeoutMs);
            client.Write(bytes, 0, bytes.Length);
            client.Flush();
            return true;
        }
        catch
        {
            return false;
        }
    }

    private static void StartHost()
    {
        try
        {
            var exe = Environment.ProcessPath;
            if (exe is null)
            {
                return;
            }

            Process.Start(new ProcessStartInfo
            {
                FileName = exe,
                Arguments = "host",
                UseShellExecute = false,
                CreateNoWindow = true,
            });
        }
        catch
        {
            // 拉起失败则发送会重试超时后放弃
        }
    }
}