/// <summary>
/// Returns the authorization URL of the specified provider, query parameters and return URL.
/// </summary>
/// <param name="clientName">
/// The provider name, through which it is necessary to authorize the current user; or the name of the registered client.
/// </param>
/// <param name="parameters">Additional parameters to be passed to the authorization URL.</param>
/// <param name="returnUrl">The address to which the user is redirected after the authorization.</param>
/// <param name="state">Custom state associated with authorization request.</param>
/// <exception cref="NullHttpContextException">
/// The exception that is thrown when you try to access methods that are designed for web projects.
/// </exception>
public static string GetAuthorizationUrl(ClientName clientName, NameValueCollection parameters, string returnUrl, object state)
{
if (!OAuthManager.RegisteredClients.ContainsKey(clientName))
{
throw new ClientIsNotRegisteredException();
}
// get normal client name
clientName = OAuthManager.RegisteredClients.Keys.First(k => k == clientName);
// create new instance of the client
var client = OAuthManager.RegisteredClients[clientName].Clone(parameters, returnUrl);
// add request
OAuthManager.AddRequest(client.State, clientName, client, state);
// return url
return(client.AuthorizationUrl);
}
/// <summary>
/// Adds the specified request to the collection.
/// </summary>
/// <param name="key">The unique request key.</param>
/// <param name="clientName">The client name.</param>
/// <param name="client">The client instance.</param>
internal static void AddRequest(string key, ClientName clientName, OAuthBase client)
{
OAuthManager.AddRequest(key, clientName, client, null);
}
