/*
    * ====================================================================
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF 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.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   *
   */
  
  package org.apache.http.impl.conn;
  
  import java.io.IOException;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.http.HttpException;
  import org.apache.http.HttpResponse;
  import org.apache.http.HttpResponseFactory;
  import org.apache.http.NoHttpResponseException;
  import org.apache.http.ProtocolException;
  import org.apache.http.StatusLine;
  import org.apache.http.annotation.ThreadSafe;
  import org.apache.http.config.MessageConstraints;
  import org.apache.http.impl.DefaultHttpResponseFactory;
  import org.apache.http.impl.io.AbstractMessageParser;
  import org.apache.http.io.SessionInputBuffer;
  import org.apache.http.message.BasicLineParser;
  import org.apache.http.message.LineParser;
  import org.apache.http.message.ParserCursor;
  import org.apache.http.params.HttpParams;
  import org.apache.http.util.Args;
  import org.apache.http.util.CharArrayBuffer;
  
  /**
   * Lenient HTTP response parser implementation that can skip malformed data until
   * a valid HTTP response message head is encountered.
   *
   * @since 4.2
   */
  @SuppressWarnings("deprecation")
  @ThreadSafe // no public methods
  public class DefaultHttpResponseParser extends AbstractMessageParser<HttpResponse> {
  
      private final Log log = LogFactory.getLog(getClass());
  
      private final HttpResponseFactory responseFactory;
      private final CharArrayBuffer lineBuf;
  
      /**
       * @deprecated (4.3) use {@link DefaultHttpResponseParser#DefaultHttpResponseParser(
       *   SessionInputBuffer, LineParser, HttpResponseFactory, MessageConstraints)}
       */
      @Deprecated
      public DefaultHttpResponseParser(
              final SessionInputBuffer buffer,
              final LineParser parser,
              final HttpResponseFactory responseFactory,
              final HttpParams params) {
          super(buffer, parser, params);
          Args.notNull(responseFactory, "Response factory");
          this.responseFactory = responseFactory;
          this.lineBuf = new CharArrayBuffer(128);
      }
  
      /**
       * Creates new instance of DefaultHttpResponseParser.
       *
       * @param buffer the session input buffer.
       * @param lineParser the line parser. If <code>null</code> {@link BasicLineParser#INSTANCE}
       *   will be used.
       * @param responseFactory HTTP response factory. If <code>null</code>
       *   {@link DefaultHttpResponseFactory#INSTANCE} will be used.
       * @param constraints the message constraints. If <code>null</code>
       *   {@link MessageConstraints#DEFAULT} will be used.
       *
       * @since 4.3
       */
      public DefaultHttpResponseParser(
              final SessionInputBuffer buffer,
              final LineParser lineParser,
              final HttpResponseFactory responseFactory,
             final MessageConstraints constraints) {
         super(buffer, lineParser, constraints);
         this.responseFactory = responseFactory != null ? responseFactory :
                 DefaultHttpResponseFactory.INSTANCE;
         this.lineBuf = new CharArrayBuffer(128);
     }
 
     /**
      * Creates new instance of DefaultHttpResponseParser.
      *
      * @param buffer the session input buffer.
      * @param constraints the message constraints. If <code>null</code>
      *   {@link MessageConstraints#DEFAULT} will be used.
      *
      * @since 4.3
      */
     public DefaultHttpResponseParser(
         final SessionInputBuffer buffer, final MessageConstraints constraints) {
         this(buffer, null, null, constraints);
     }
 
     /**
      * Creates new instance of DefaultHttpResponseParser.
      *
      * @param buffer the session input buffer.
      *
      * @since 4.3
      */
     public DefaultHttpResponseParser(final SessionInputBuffer buffer) {
         this(buffer, null, null, MessageConstraints.DEFAULT);
     }
 
     @Override
     protected HttpResponse parseHead(
             final SessionInputBuffer sessionBuffer) throws IOException, HttpException {
         //read out the HTTP status string
         int count = 0;
         ParserCursor cursor = null;
         do {
             // clear the buffer
             this.lineBuf.clear();
             final int i = sessionBuffer.readLine(this.lineBuf);
             if (i == -1 && count == 0) {
                 // The server just dropped connection on us
                 throw new NoHttpResponseException("The target server failed to respond");
             }
             cursor = new ParserCursor(0, this.lineBuf.length());
             if (lineParser.hasProtocolVersion(this.lineBuf, cursor)) {
                 // Got one
                 break;
             } else if (i == -1 || reject(this.lineBuf, count)) {
                 // Giving up
                 throw new ProtocolException("The server failed to respond with a " +
                         "valid HTTP response");
             }
             if (this.log.isDebugEnabled()) {
                 this.log.debug("Garbage in response: " + this.lineBuf.toString());
             }
             count++;
         } while(true);
         //create the status line from the status string
         final StatusLine statusline = lineParser.parseStatusLine(this.lineBuf, cursor);
         return this.responseFactory.newHttpResponse(statusline, null);
     }
 
     protected boolean reject(final CharArrayBuffer line, final int count) {
         return false;
     }
 
 }