AuthenticateAsync()
{
const int port = 8765;
var redirectUri = $"http://localhost:{port}/oauth2/callback";
if (string.IsNullOrWhiteSpace(_clientId) || string.IsNullOrWhiteSpace(_clientSecret))
return null;
using var listener = new HttpListener();
listener.Prefixes.Add($"{redirectUri}/");
listener.Start();
Process.Start(new ProcessStartInfo(GetAuthorizationUrl(redirectUri)) { UseShellExecute = true });
HttpListenerContext context;
try
{
using var cts = new CancellationTokenSource(TimeSpan.FromMinutes(5));
context = await listener.GetContextAsync().WaitAsync(cts.Token);
}
catch (OperationCanceledException)
{
return null;
}
var code = context.Request.QueryString["code"];
var error = context.Request.QueryString["error"];
var html = error != null
? "Sign-in failed
You can close this window and return to ytLlive.
"
: "Sign-in successful!
You can close this window and return to ytLlive.
";
var buffer = Encoding.UTF8.GetBytes(html);
context.Response.ContentType = "text/html; charset=utf-8";
context.Response.ContentLength64 = buffer.Length;
await context.Response.OutputStream.WriteAsync(buffer);
context.Response.Close();
if (error != null || string.IsNullOrEmpty(code))
return null;
return await ExchangeCodeForToken(code, redirectUri);
}
public async Task ExchangeCodeForToken(string code, string redirectUri)
{
var body = new FormUrlEncodedContent(new Dictionary
{
["code"] = code,
["client_id"] = _clientId,
["client_secret"] = _clientSecret,
["redirect_uri"] = redirectUri,
["grant_type"] = "authorization_code"
});
var response = await _http.PostAsync(TokenEndpoint, body);
if (!response.IsSuccessStatusCode)
return null;
var json = await response.Content.ReadAsStringAsync();
var tokenData = JsonSerializer.Deserialize(json);
var accessToken = tokenData.GetProperty("access_token").GetString()!;
var refreshToken = tokenData.GetProperty("refresh_token").GetString()!;
var expiresIn = tokenData.GetProperty("expires_in").GetInt32();
// Fetch channel info
return await FetchChannelInfo(accessToken, refreshToken, expiresIn);
}
public async Task RefreshToken()
{
if (CurrentChannel == null) return false;
var body = new FormUrlEncodedContent(new Dictionary
{
["refresh_token"] = CurrentChannel.RefreshToken,
["client_id"] = _clientId,
["client_secret"] = _clientSecret,
["grant_type"] = "refresh_token"
});
var response = await _http.PostAsync(TokenEndpoint, body);
if (!response.IsSuccessStatusCode) return false;
var json = await response.Content.ReadAsStringAsync();
var tokenData = JsonSerializer.Deserialize(json);
CurrentChannel.AccessToken = tokenData.GetProperty("access_token").GetString()!;
CurrentChannel.TokenExpiry = DateTime.UtcNow.AddSeconds(tokenData.GetProperty("expires_in").GetInt32());
_sessionChanged?.Invoke(CurrentChannel);
return true;
}
private async Task FetchChannelInfo(string accessToken, string refreshToken, int expiresIn)
{
_http.DefaultRequestHeaders.Authorization = new("Bearer", accessToken);
var response = await _http.GetAsync("https://www.googleapis.com/youtube/v3/channels?part=snippet&mine=true");
if (!response.IsSuccessStatusCode) return null;
var json = await response.Content.ReadAsStringAsync();
var data = JsonSerializer.Deserialize(json);
var items = data.GetProperty("items");
if (items.GetArrayLength() == 0) return null;
var snippet = items[0].GetProperty("snippet");
CurrentChannel = new YouTubeChannel
{
ChannelId = items[0].GetProperty("id").GetString()!,
DisplayName = snippet.GetProperty("title").GetString()!,
ProfileImageUrl = snippet.GetProperty("thumbnails").GetProperty("default").GetProperty("url").GetString()!,
AccessToken = accessToken,
RefreshToken = refreshToken,
TokenExpiry = DateTime.UtcNow.AddSeconds(expiresIn)
};
_sessionChanged?.Invoke(CurrentChannel);
return CurrentChannel;
}
}