/* See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * Esri Inc. licenses this file to You 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 com.esri.gpt.framework.http;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

/**
 * Stream based provider for the content of an HTTP request body.
 */
public class StreamProvider extends ContentProvider {
  
  /** instance variables ====================================================== */
  private InputStream content;
  private long        contentLength = -1;
  private String      contentType;
  
  /** constructors ============================================================ */
    
  /**
   * Constructs with an associated request content input stream, content length and content type.
   * @param content the input stream providing the content of the HTTP request body 
   * @param contentLength the length (in bytes) of the HTTP request body,
   *        use -1 if the length is unknown
   * @param contentType the content type of the HTTP request body,
   *        use null if unknown, include a charset if applicable,
   *        e.g. text/xml; charset=UTF-8
   */
  public StreamProvider(InputStream content, long contentLength, String contentType) {
    super(); 
    this.content = content;
    this.contentLength = contentLength;
    this.contentType = contentType;
  }
  
  /** properties  ============================================================= */
    
  /**
   * Gets the content length (in bytes) to be provided in the HTTP request header.
   * @return the request content length (in bytes, use -1 if unknown);
   */
  @Override
  public long getContentLength() {
    return this.contentLength;
  }
  
  /**
   * Gets the content type to be provided in the HTTP request header.
   * <br/>Include a charset if applicable, e.g. text/xml; charset=UTF-8
   * @return the request content type
   */
  @Override
  public String getContentType() {
    return this.contentType;
  }
  
  /**
   * Tests if the HTTP request content can be written to the output stream more than once. 
   * @return always false (override if necessary)
   */
  @Override
  public boolean isRepeatable() {
    return false;
  }
  
  /** methods ================================================================= */
      
  /**
   * Writes the content of the HTTP request body to an output stream.
   * @param request the HTTP request that is executing
   * @param destination the output stream to which data will be written
   * @throws IOException if an exception occurs
   */
  @Override
  public void writeRequest(HttpClientRequest request, OutputStream destination) throws IOException {
    if (this.content != null) {
      this.executeIO(this.content,destination);
    }
  }
    
}