MeWeb/src/MeWeb.Core/Net/SpeedCheck.cs

using System.Diagnostics;

using MeWeb.Shared;

namespace MeWeb.Core.Net;

public class SpeedReport
{
  public double DownMbps { get; set; }
  public double UpMbps { get; set; }
  public int DownBytes { get; set; }
  public int UpBytes { get; set; }
  public bool Limited { get; set; }
}

public static class SpeedCheck
{
  public static async Task<SpeedReport> Run(HttpClient https, LinkKind kind, CancellationToken ct)
  {
    var mobile = kind == LinkKind.Mobile;
    var report = new SpeedReport { DownBytes = mobile ? 2 * 1024 * 1024 : 12 * 1024 * 1024, UpBytes = mobile ? 1024 * 1024 : 4 * 1024 * 1024 };
    try
    {
      using var timeout = CancellationTokenSource.CreateLinkedTokenSource(ct);
      timeout.CancelAfter(TimeSpan.FromSeconds(30));
      var clock = Stopwatch.StartNew();
      using (var response = await https.GetAsync(Endpoints.Base + Endpoints.Speed.GET_M_Down(report.DownBytes), HttpCompletionOption.ResponseHeadersRead, timeout.Token))
      {
        if ((int)response.StatusCode == 429)
        {
          report.Limited = true;
          return report;
        }
        response.EnsureSuccessStatusCode();
        await using var body = await response.Content.ReadAsStreamAsync(timeout.Token);
        var buffer = new byte[64 * 1024];
        long total = 0;
        int read;
        while ((read = await body.ReadAsync(buffer, timeout.Token)) > 0) total += read;
        report.DownMbps = Mbps(total, clock.Elapsed);
      }

      var payload = new byte[report.UpBytes];
      Random.Shared.NextBytes(payload);
      clock.Restart();
      using (var response = await https.PostAsync(Endpoints.Base + Endpoints.Speed.POST_Up, new ByteArrayContent(payload), timeout.Token))
      {
        if (response.IsSuccessStatusCode) report.UpMbps = Mbps(payload.Length, clock.Elapsed);
      }
    }
    catch (Exception ex) when (ex is HttpRequestException or TaskCanceledException or IOException && !ct.IsCancellationRequested)
    {
    }
    return report;
  }

  static double Mbps(long bytes, TimeSpan elapsed) => elapsed.TotalSeconds <= 0 ? 0 : Math.Round(bytes * 8 / elapsed.TotalSeconds / 1_000_000, 1);
}