using System.Net;
using Microsoft.AspNetCore.Hosting.Server;

public class PocKestrelAutoPort
{
    public static async Task RunPoc()
    {
        var host = Host.CreateDefaultBuilder()
            .ConfigureWebHostDefaults(webBuilder =>
            {
                webBuilder.ConfigureKestrel(serverOptions =>
                {
                    serverOptions.Listen(IPAddress.Parse("127.0.0.1"), 0); // 使用端口 0，让系统自动分配端口
                });

                webBuilder.Configure(app =>
                {
                    app.Run(async context =>
                    {
                        await context.Response.WriteAsync("Hello, world!");
                    });
                });
            })
            .Build();

        // 启动后获取实际端口
        host.Start();

        var addressFeature = host.Services.GetRequiredService<IServer>().Features
            .Get<Microsoft.AspNetCore.Hosting.Server.Features.IServerAddressesFeature>();

        var boundAddress = addressFeature.Addresses.FirstOrDefault();
        System.Console.WriteLine($"Server bound to: {boundAddress}");

        await host.WaitForShutdownAsync();

    }
}