<%#
 Copyright 2013-2018 the original author or authors from the JHipster project.

 This file is part of the JHipster project, see https://jhipster.github.io/
 for more information.

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0

 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
-%>
package <%=packageName%>.security.oauth2;

import <%=packageName%>.config.oauth2.OAuth2Properties;
import io.github.jhipster.config.JHipsterProperties;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.http.HttpHeaders;
import org.springframework.stereotype.Component;
import org.springframework.util.Base64Utils;
import org.springframework.util.MultiValueMap;
import org.springframework.web.client.RestTemplate;

import java.nio.charset.StandardCharsets;

/**
 * Client talking to UAA's token endpoint to do different OAuth2 grants.
 */
@Component
public class UaaTokenEndpointClient extends OAuth2TokenEndpointClientAdapter implements OAuth2TokenEndpointClient {

    public UaaTokenEndpointClient(@Qualifier("loadBalancedRestTemplate") RestTemplate restTemplate,
                                  JHipsterProperties jHipsterProperties, OAuth2Properties oAuth2Properties) {
        super(restTemplate, jHipsterProperties, oAuth2Properties);
    }

    @Override
    protected void addAuthentication(HttpHeaders reqHeaders, MultiValueMap<String, String> formParams) {
        reqHeaders.add("Authorization", getAuthorizationHeader());
    }

    /**
     * @return a Basic authorization header to be used to talk to UAA.
     */
    protected String getAuthorizationHeader() {
        String clientId = getClientId();
        String clientSecret = getClientSecret();
        String authorization = clientId + ":" + clientSecret;
        return "Basic " + Base64Utils.encodeToString(authorization.getBytes(StandardCharsets.UTF_8));
    }

}