/// <summary>
/// Present the Last.fm authentication UI and attempt to obtain a session key.
/// </summary>
/// <param name="authView">A WebView to display the Last.fm authentication page.</param>
/// <param name="onSuccess">A callback for when the authentication is successful.</param>
/// <param name="onFailure">A callback for when the authentication fails.</param>
/// <returns>An async Task.</returns>
public async Task LastFmLogin(Windows.UI.Xaml.Controls.WebView authView, Func<bool> onSuccess, Func<bool> onFailure)
{
Contract.Requires(authView != null);
Contract.Requires(onSuccess != null);
Contract.Requires(onFailure != null);
try
{
HttpResponseMessage getTokenMessage = await __client.GetAsync(LastFmApiSecrets.LASTFMAPI_GET_TOKEN);
string tokenResponse = await getTokenMessage.Content.ReadAsStringAsync();
string token = JsonObject
.Parse(tokenResponse)
.GetNamedString("token");
string authUri = string.Format(LastFmApiSecrets.LASTFMAPI_AUTH_URL_FORMAT, token);
authView.LoadCompleted += async (sender, e) =>
{
try
{
if (e.Uri.LocalPath.ToString().ToLowerInvariant() == LastFmApiSecrets.LASTFMAPI_AUTH_SUCCESS_URL)
{
string getSessionSignature = string.Format(LastFmApiSecrets.LASTFMAPI_GET_SESSION_SIGN_FORMAT, token);
string getSessionSignatureMd5 = getSessionSignature.GetMd5Hash();
string getSession = string.Format(LastFmApiSecrets.LASTFMAPI_GET_SESSION_FORMAT, token, getSessionSignatureMd5);
HttpResponseMessage getSessionMessage = await __client.GetAsync(getSession);
string sessionResponse = await getSessionMessage.Content.ReadAsStringAsync();
JsonObject session = JsonObject
.Parse(sessionResponse)
.GetNamedObject("session");
LogIn(session.GetNamedString("name"), session.GetNamedString("key"));
onSuccess();
}
}
catch (Exception)
{
// Failure after user interaction
onFailure();
}
};
authView.NavigationFailed += (sender, e) =>
{
// WebView navigation failure
onFailure();
};
authView.Navigate(new Uri(authUri));
}
catch (Exception)
{
// Failure before user interaction
onFailure();
}
}
