public function buildAuthUrl(array $params = [])
{
$defaultParams = ['client_id' => $this->clientId, 'response_type' => 'code', 'redirect_uri' => $this->getReturnUrl(), 'xoauth_displayname' => Yii::$app->name];
if (!empty($this->scope)) {
$defaultParams['scope'] = $this->scope;
}
if ($this->validateAuthState) {
$authState = $this->generateAuthState();
$this->setState('authState', $authState);
$defaultParams['state'] = $authState;
}
return $this->composeUrl($this->authUrl, array_merge($defaultParams, $params));
}