using System.Diagnostics;
using System.Net;
using System.Net.Sockets;

namespace Enciphered.Blazor.UIComponents.Tests;

/// <summary>
/// Launches the demo Blazor app as a separate process on a random free port.
/// Shared across all tests in the assembly via [SetUpFixture].
/// </summary>
public sealed class DemoServerFixture : IDisposable
{
    private Process? _process;

    public string BaseUrl { get; private set; } = string.Empty;

    public async Task StartAsync()
    {
        var port = GetFreePort();
        BaseUrl = $"http://localhost:{port}";

        // Resolve the demo project directory (navigate up from test bin output)
        var testDir = AppContext.BaseDirectory; // …Tests/bin/Debug/net9.0
        var solutionRoot = Path.GetFullPath(Path.Combine(testDir, "..", "..", "..", ".."));
        var demoProjectDir = Path.Combine(solutionRoot, "Enciphered.Blazor.UIComponents.Demo");

        if (!Directory.Exists(demoProjectDir))
            throw new DirectoryNotFoundException($"Demo project not found at: {demoProjectDir}");

        _process = new Process
        {
            StartInfo = new ProcessStartInfo
            {
                FileName = "dotnet",
                Arguments = $"run --no-build --urls {BaseUrl}",
                WorkingDirectory = demoProjectDir,
                UseShellExecute = false,
                RedirectStandardOutput = true,
                RedirectStandardError = true,
                CreateNoWindow = true,
                Environment =
                {
                    ["ASPNETCORE_ENVIRONMENT"] = "Development",
                    ["DOTNET_NOLOGO"] = "1"
                }
            }
        };

        _process.Start();

        // Wait for the server to be ready by polling the URL
        using var httpClient = new HttpClient { Timeout = TimeSpan.FromSeconds(2) };
        var deadline = DateTime.UtcNow.AddSeconds(30);

        while (DateTime.UtcNow < deadline)
        {
            try
            {
                var response = await httpClient.GetAsync(BaseUrl);
                if (response.IsSuccessStatusCode)
                    return;
            }
            catch
            {
                // Server not ready yet
            }
            await Task.Delay(500);
        }

        throw new TimeoutException($"Demo server did not start within 30 seconds at {BaseUrl}");
    }

    public void Dispose()
    {
        if (_process is not null && !_process.HasExited)
        {
            _process.Kill(entireProcessTree: true);
            _process.WaitForExit(5000);
            _process.Dispose();
        }
    }

    private static int GetFreePort()
    {
        using var listener = new TcpListener(IPAddress.Loopback, 0);
        listener.Start();
        var port = ((IPEndPoint)listener.LocalEndpoint).Port;
        listener.Stop();
        return port;
    }
}