180 lines
6.7 KiB
C#
180 lines
6.7 KiB
C#
using System.Diagnostics;
|
|
using System.Net;
|
|
using System.Net.Http;
|
|
using System.Text;
|
|
using System.Text.Json;
|
|
using ytLive.Models;
|
|
|
|
namespace ytLive.Services;
|
|
|
|
/// <summary>
|
|
/// Handles YouTube OAuth2 authentication flow.
|
|
/// Uses a local HTTP listener for the redirect callback.
|
|
/// </summary>
|
|
public class YouTubeAuthService
|
|
{
|
|
private const string AuthorizationEndpoint = "https://accounts.google.com/o/oauth2/v2/auth";
|
|
private const string TokenEndpoint = "https://oauth2.googleapis.com/token";
|
|
private const string Scope = "https://www.googleapis.com/auth/youtube https://www.googleapis.com/auth/youtube.force-ssl";
|
|
|
|
private readonly string _clientId;
|
|
private readonly string _clientSecret;
|
|
private readonly HttpClient _http;
|
|
private readonly Action<YouTubeChannel>? _sessionChanged;
|
|
|
|
public YouTubeChannel? CurrentChannel { get; private set; }
|
|
|
|
public YouTubeAuthService(string clientId, string clientSecret, HttpClient? http = null,
|
|
Action<YouTubeChannel>? sessionChanged = null)
|
|
{
|
|
_clientId = clientId;
|
|
_clientSecret = clientSecret;
|
|
_http = http ?? new HttpClient();
|
|
_sessionChanged = sessionChanged;
|
|
}
|
|
|
|
/// <summary>Replaces the current session (used when a saved token loads at startup).</summary>
|
|
public void SetSession(YouTubeChannel channel)
|
|
{
|
|
CurrentChannel = channel;
|
|
}
|
|
|
|
public string GetAuthorizationUrl(string redirectUri)
|
|
{
|
|
var query = new[]
|
|
{
|
|
("client_id", _clientId),
|
|
("redirect_uri", redirectUri),
|
|
("response_type", "code"),
|
|
("scope", Scope),
|
|
("access_type", "offline"),
|
|
("prompt", "consent"),
|
|
};
|
|
|
|
var encoded = string.Join("&", query.Select(kv =>
|
|
$"{Uri.EscapeDataString(kv.Item1)}={Uri.EscapeDataString(kv.Item2)}"));
|
|
|
|
return $"{AuthorizationEndpoint}?{encoded}";
|
|
}
|
|
|
|
public async Task<YouTubeChannel?> 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
|
|
? "<html><body style=\"font-family:sans-serif\"><h2>Sign-in failed</h2><p>You can close this window and return to ytLlive.</p></body></html>"
|
|
: "<html><body style=\"font-family:sans-serif\"><h2>Sign-in successful!</h2><p>You can close this window and return to ytLlive.</p></body></html>";
|
|
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<YouTubeChannel?> ExchangeCodeForToken(string code, string redirectUri)
|
|
{
|
|
var body = new FormUrlEncodedContent(new Dictionary<string, string>
|
|
{
|
|
["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<JsonElement>(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<bool> RefreshToken()
|
|
{
|
|
if (CurrentChannel == null) return false;
|
|
|
|
var body = new FormUrlEncodedContent(new Dictionary<string, string>
|
|
{
|
|
["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<JsonElement>(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<YouTubeChannel?> 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<JsonElement>(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;
|
|
}
|
|
}
|