/*
    * Copyright 2002-2014 the original author or authors.
    *
    * 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 org.springframework.http.client;
  
  import java.io.IOException;
  import java.net.URI;
  import java.util.List;
  import java.util.Map;
  
  import org.apache.http.HttpEntity;
  import org.apache.http.HttpEntityEnclosingRequest;
  import org.apache.http.client.methods.CloseableHttpResponse;
  import org.apache.http.client.methods.HttpUriRequest;
  import org.apache.http.entity.ByteArrayEntity;
  import org.apache.http.impl.client.CloseableHttpClient;
  import org.apache.http.protocol.HTTP;
  import org.apache.http.protocol.HttpContext;
  
  import org.springframework.http.HttpHeaders;
  import org.springframework.http.HttpMethod;
  import org.springframework.util.StringUtils;
  
  /**
   * {@link org.springframework.http.client.ClientHttpRequest} implementation that uses
   * Apache HttpComponents HttpClient to execute requests.
   *
   * <p>Created via the {@link HttpComponentsClientHttpRequestFactory}.
   *
   * <p><b>NOTE:</b> Requires Apache HttpComponents 4.3 or higher, as of Spring 4.0.
   *
   * @author Oleg Kalnichevski
   * @author Arjen Poutsma
   * @author Juergen Hoeller
   * @since 3.1
   * @see HttpComponentsClientHttpRequestFactory#createRequest(URI, HttpMethod)
   */
  final class HttpComponentsClientHttpRequest extends AbstractBufferingClientHttpRequest {
  
  	private final CloseableHttpClient httpClient;
  
  	private final HttpUriRequest httpRequest;
  
  	private final HttpContext httpContext;
  
  
  	HttpComponentsClientHttpRequest(CloseableHttpClient httpClient, HttpUriRequest httpRequest, HttpContext httpContext) {
  		this.httpClient = httpClient;
  		this.httpRequest = httpRequest;
  		this.httpContext = httpContext;
  	}
  
  
  	@Override
  	public HttpMethod getMethod() {
  		return HttpMethod.valueOf(this.httpRequest.getMethod());
  	}
  
  	@Override
  	public URI getURI() {
  		return this.httpRequest.getURI();
  	}
  
  	HttpContext getHttpContext() {
  		return this.httpContext;
  	}
  
  
  	@Override
  	protected ClientHttpResponse executeInternal(HttpHeaders headers, byte[] bufferedOutput) throws IOException {
  		addHeaders(this.httpRequest, headers);
  
  		if (this.httpRequest instanceof HttpEntityEnclosingRequest) {
  			HttpEntityEnclosingRequest entityEnclosingRequest = (HttpEntityEnclosingRequest) this.httpRequest;
  			HttpEntity requestEntity = new ByteArrayEntity(bufferedOutput);
  			entityEnclosingRequest.setEntity(requestEntity);
  		}
  		CloseableHttpResponse httpResponse = this.httpClient.execute(this.httpRequest, this.httpContext);
  		return new HttpComponentsClientHttpResponse(httpResponse);
  	}
  
  
  	/**
  	 * Add the given headers to the given HTTP request.
  	 * @param httpRequest the request to add the headers to
  	 * @param headers the headers to add
 	 */
 	static void addHeaders(HttpUriRequest httpRequest, HttpHeaders headers) {
 		for (Map.Entry<String, List<String>> entry : headers.entrySet()) {
 			String headerName = entry.getKey();
 			if (HttpHeaders.COOKIE.equalsIgnoreCase(headerName)) {  // RFC 6265
 				String headerValue = StringUtils.collectionToDelimitedString(entry.getValue(), "; ");
 				httpRequest.addHeader(headerName, headerValue);
 			}
 			else if (!HTTP.CONTENT_LEN.equalsIgnoreCase(headerName) &&
 					!HTTP.TRANSFER_ENCODING.equalsIgnoreCase(headerName)) {
 				for (String headerValue : entry.getValue()) {
 					httpRequest.addHeader(headerName, headerValue);
 				}
 			}
 		}
 	}
 
 }