//
//  ========================================================================
//  Copyright (c) 1995-2014 Mort Bay Consulting Pty. Ltd.
//  ------------------------------------------------------------------------
//  All rights reserved. This program and the accompanying materials
//  are made available under the terms of the Eclipse Public License v1.0
//  and Apache License v2.0 which accompanies this distribution.
//
//      The Eclipse Public License is available at
//      http://www.eclipse.org/legal/epl-v10.html
//
//      The Apache License v2.0 is available at
//      http://www.opensource.org/licenses/apache2.0.php
//
//  You may elect to redistribute this code under either of these licenses.
//  ========================================================================
//

package org.eclipse.jetty.http;

import java.io.IOException;

import org.eclipse.jetty.io.Buffer;
import org.eclipse.jetty.io.BufferCache.CachedBuffer;
import org.eclipse.jetty.io.BufferUtil;
import org.eclipse.jetty.io.Buffers;
import org.eclipse.jetty.io.ByteArrayBuffer;
import org.eclipse.jetty.io.EndPoint;
import org.eclipse.jetty.io.EofException;
import org.eclipse.jetty.io.View;
import org.eclipse.jetty.util.StringUtil;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public final class HttpParser
{
	private static final Logger LOG = LoggerFactory.getLogger(HttpParser.class);

	// States
	private static final int STATE_START=-14;
	private static final int STATE_FIELD0=-13;
	private static final int STATE_SPACE1=-12;
	private static final int STATE_STATUS=-11;
	private static final int STATE_URI=-10;
	private static final int STATE_SPACE2=-9;
	private static final int STATE_END0=-8;
	private static final int STATE_END1=-7;
	private static final int STATE_FIELD2=-6;
	private static final int STATE_HEADER=-5;
	private static final int STATE_HEADER_NAME=-4;
	private static final int STATE_HEADER_IN_NAME=-3;
	private static final int STATE_HEADER_VALUE=-2;
	private static final int STATE_HEADER_IN_VALUE=-1;
	private static final int STATE_END=0;
	private static final int STATE_EOF_CONTENT=1;
	private static final int STATE_CONTENT=2;
	private static final int STATE_CHUNKED_CONTENT=3;
	private static final int STATE_CHUNK_SIZE=4;
	private static final int STATE_CHUNK_PARAMS=5;
	private static final int STATE_CHUNK=6;
	private static final int STATE_SEEKING_EOF=7;

	private final EventHandler _handler;
	private final Buffers _buffers; // source of buffers
	private final EndPoint _endp;
	private Buffer _header; // Buffer for header data (and small _content)
	private Buffer _body; // Buffer for large content
	private Buffer _buffer; // The current buffer in use (either _header or _content)
	private CachedBuffer _cached;
	private final View.CaseInsensitive _tok0 = new View.CaseInsensitive(); // Saved token: header name, request method or response version
	private final View.CaseInsensitive _tok1 = new View.CaseInsensitive(); // Saved token: header value, request URI or response code
	private String _multiLineValue;
	private int _responseStatus; // If >0 then we are parsing a response
	private boolean _persistent;

	protected final View  _contentView = new View(); // View of the content in the buffer for {@link Input}
	protected int _state = STATE_START;
	protected byte _eol;
	protected int _length;
	protected long _contentLength;
	protected long _contentPosition;
	protected int _chunkLength;
	protected int _chunkPosition;
	private boolean _headResponse;

	public HttpParser(Buffers buffers, EndPoint endp, EventHandler handler)
	{
		_buffers = buffers;
		_endp = endp;
		_handler = handler;
	}

	public long getContentLength()
	{
		return _contentLength;
	}

	public long getContentRead()
	{
		return _contentPosition;
	}

	/* ------------------------------------------------------------ */
	/** Set if a HEAD response is expected
	 * @param head
	 */
	public void setHeadResponse(boolean head)
	{
		_headResponse = head;
	}

	public boolean isChunking()
	{
		return _contentLength==HttpTokens.CHUNKED_CONTENT;
	}

	public boolean isIdle()
	{
		return _state==STATE_START;
	}

	public boolean isComplete()
	{
		return _state==STATE_END;
	}

	public boolean isPersistent()
	{
		return _persistent;
	}

	public void setPersistent(boolean persistent)
	{
		_persistent = persistent;
		if (!_persistent &&(_state==STATE_END || _state==STATE_START))
			_state=STATE_SEEKING_EOF;
	}

	/* ------------------------------------------------------------------------------- */
	/**
	 * Parse until END state.
	 * This method will parse any remaining content in the current buffer as long as there is
	 * no unconsumed content. It does not care about the {@link #getState current state} of the parser.
	 * @see #parse
	 * @see #parseNext
	 */
	public boolean parseAvailable() throws IOException
	{
		boolean progress = parseNext() > 0;

		// continue parsing
		while (!isComplete() && _buffer!=null && _buffer.length()>0 && !_contentView.hasContent())
		{
			progress |= parseNext()>0;
		}
		return progress;
	}


	/* ------------------------------------------------------------------------------- */
	/**
	 * Parse until next Event.
	 * @return an indication of progress <0 EOF, 0 no progress, >0 progress.
	 */
	private int parseNext() throws IOException
	{
		try
		{
			int progress=0;

			if (_state == STATE_END)
				return 0;

			if (_buffer==null)
				_buffer=getHeaderBuffer();


			if (_state == STATE_CONTENT && _contentPosition == _contentLength)
			{
				_state=STATE_END;
				_handler.messageComplete(_contentPosition);
				return 1;
			}

			int length=_buffer.length();

			// Fill buffer if we can
			if (length == 0)
			{
				int filled=-1;
				IOException ex=null;
				try
				{
					filled=fill();
					LOG.debug("filled {}/{}",filled,_buffer.length());
				}
				catch(IOException e)
				{
					LOG.debug(this.toString(),e);
					ex=e;
				}

				if (filled > 0 )
					progress++;
				else if (filled < 0 )
				{
					_persistent=false;

					// do we have content to deliver?
					if (_state>STATE_END)
					{
						if (_buffer.length()>0 && !_headResponse)
						{
							Buffer chunk=_buffer.get(_buffer.length());
							_contentPosition += chunk.length();
							_contentView.update(chunk);
							_handler.content(chunk); // May recurse here
						}
					}

					// was this unexpected?
					switch(_state)
					{
						case STATE_END:
						case STATE_SEEKING_EOF:
							_state=STATE_END;
							break;

						case STATE_EOF_CONTENT:
							_state=STATE_END;
							_handler.messageComplete(_contentPosition);
							break;

						default:
							_state=STATE_END;
							if (!_headResponse)
								_handler.earlyEOF();
							_handler.messageComplete(_contentPosition);
					}

					if (ex!=null)
						throw ex;

					if (!isComplete() && !isIdle())
						throw new EofException();

					return -1;
				}
				length=_buffer.length();
			}


			// Handle header states
			byte ch;
			byte[] array=_buffer.array();
			int last=_state;
			while (_state<STATE_END && length-->0)
			{
				if (last!=_state)
				{
					progress++;
					last=_state;
				}

				ch=_buffer.get();

				if (_eol == HttpTokens.CARRIAGE_RETURN)
				{
					if (ch == HttpTokens.LINE_FEED)
					{
						_eol=HttpTokens.LINE_FEED;
						continue;
					}
					throw new HttpException(HttpStatus.BAD_REQUEST_400);
				}
				_eol=0;

				switch (_state)
				{
					case STATE_START:
						_contentLength=HttpTokens.UNKNOWN_CONTENT;
						_cached=null;
						if (ch > HttpTokens.SPACE || ch<0)
						{
							_buffer.mark();
							_state=STATE_FIELD0;
						}
						break;

					case STATE_FIELD0:
						if (ch == HttpTokens.SPACE)
						{
							_tok0.update(_buffer.markIndex(), _buffer.getIndex() - 1);
							_responseStatus=HttpVersions.CACHE.get(_tok0)==null?-1:0;
							_state=STATE_SPACE1;
							continue;
						}
						else if (ch < HttpTokens.SPACE && ch>=0)
						{
							throw new HttpException(HttpStatus.BAD_REQUEST_400);
						}
						break;

					case STATE_SPACE1:
						if (ch > HttpTokens.SPACE || ch<0)
						{
							_buffer.mark();
							if (_responseStatus>=0)
							{
								_state=STATE_STATUS;
								_responseStatus=ch-'0';
							}
							else
								_state=STATE_URI;
						}
						else if (ch < HttpTokens.SPACE)
						{
							throw new HttpException(HttpStatus.BAD_REQUEST_400);
						}
						break;

					case STATE_STATUS:
						if (ch == HttpTokens.SPACE)
						{
							_tok1.update(_buffer.markIndex(), _buffer.getIndex() - 1);
							_state=STATE_SPACE2;
							continue;
						}
						else if (ch>='0' && ch<='9')
						{
							_responseStatus=_responseStatus*10+(ch-'0');
							continue;
						}
						else if (ch < HttpTokens.SPACE && ch>=0)
						{
							_eol=ch;
							_state=STATE_HEADER;
							_tok0.setPutIndex(_tok0.getIndex());
							_tok1.setPutIndex(_tok1.getIndex());
							_multiLineValue=null;
							continue;
						}
						// not a digit, so must be a URI
						_state=STATE_URI;
						_responseStatus=-1;
						break;

					case STATE_URI:
						if (ch == HttpTokens.SPACE)
						{
							_tok1.update(_buffer.markIndex(), _buffer.getIndex() - 1);
							_state=STATE_SPACE2;
							continue;
						}
						else if (ch < HttpTokens.SPACE && ch>=0)
						{
							// HTTP/0.9
							_handler.startRequest(HttpMethods.CACHE.lookup(_tok0), _buffer.sliceFromMark(), null);
							_persistent=false;
							_state=STATE_SEEKING_EOF;
							_handler.headerComplete();
							_handler.messageComplete(_contentPosition);
							return 1;
						}
						break;

					case STATE_SPACE2:
						if (ch > HttpTokens.SPACE || ch<0)
						{
							_buffer.mark();
							_state=STATE_FIELD2;
						}
						else if (ch < HttpTokens.SPACE)
						{
							if (_responseStatus>0)
							{
								_eol=ch;
								_state=STATE_HEADER;
								_tok0.setPutIndex(_tok0.getIndex());
								_tok1.setPutIndex(_tok1.getIndex());
								_multiLineValue=null;
							}
							else
							{
								// HTTP/0.9
								_handler.startRequest(HttpMethods.CACHE.lookup(_tok0), _tok1, null);
								_persistent=false;
								_state=STATE_SEEKING_EOF;
								_handler.headerComplete();
								_handler.messageComplete(_contentPosition);
								return 1;
							}
						}
						break;

					case STATE_FIELD2:
						if (ch == HttpTokens.CARRIAGE_RETURN || ch == HttpTokens.LINE_FEED)
						{
							Buffer version;
							if (_responseStatus>0)
//								_handler.startResponse(version=HttpVersions.CACHE.lookup(_tok0), _responseStatus,_buffer.sliceFromMark());
								version = HttpVersions.CACHE.lookup(_tok0);
							else
								_handler.startRequest(HttpMethods.CACHE.lookup(_tok0), _tok1, version=HttpVersions.CACHE.lookup(_buffer.sliceFromMark()));
							_eol=ch;
							_persistent=HttpVersions.CACHE.getOrdinal(version)>=HttpVersions.HTTP_1_1_ORDINAL;
							_state=STATE_HEADER;
							_tok0.setPutIndex(_tok0.getIndex());
							_tok1.setPutIndex(_tok1.getIndex());
							_multiLineValue=null;
							continue;
						}
						break;

					case STATE_HEADER:
						switch(ch)
						{
							case HttpTokens.COLON:
							case HttpTokens.SPACE:
							case HttpTokens.TAB:
							{
								// header value without name - continuation?
								_length=-1;
								_state=STATE_HEADER_VALUE;
								break;
							}

							default:
							{
								// handler last header if any
								if (_cached!=null || _tok0.length() > 0 || _tok1.length() > 0 || _multiLineValue != null)
								{
									Buffer header=_cached!=null?_cached:HttpHeaders.CACHE.lookup(_tok0);
									_cached=null;
									Buffer value=_multiLineValue == null ? _tok1 : new ByteArrayBuffer(_multiLineValue);

									int ho=HttpHeaders.CACHE.getOrdinal(header);
									if (ho >= 0)
									{
										int vo;

										switch (ho)
										{
											case HttpHeaders.CONTENT_LENGTH_ORDINAL:
												if (_contentLength != HttpTokens.CHUNKED_CONTENT )
												{
													try
													{
														_contentLength=BufferUtil.toLong(value);
													}
													catch(NumberFormatException e)
													{
														LOG.trace("",e);
														throw new HttpException(HttpStatus.BAD_REQUEST_400);
													}
													if (_contentLength <= 0)
														_contentLength=HttpTokens.NO_CONTENT;
												}
												break;

											case HttpHeaders.TRANSFER_ENCODING_ORDINAL:
												value=HttpHeaderValues.CACHE.lookup(value);
												vo=HttpHeaderValues.CACHE.getOrdinal(value);
												if (HttpHeaderValues.CHUNKED_ORDINAL == vo)
													_contentLength=HttpTokens.CHUNKED_CONTENT;
												else
												{
													String c=value.toString(StringUtil.__ISO_8859_1);
													if (c.endsWith(HttpHeaderValues.CHUNKED))
														_contentLength=HttpTokens.CHUNKED_CONTENT;

													else if (c.indexOf(HttpHeaderValues.CHUNKED) >= 0)
														throw new HttpException(400,null);
												}
												break;

											case HttpHeaders.CONNECTION_ORDINAL:
												switch(HttpHeaderValues.CACHE.getOrdinal(value))
												{
													case HttpHeaderValues.CLOSE_ORDINAL:
														_persistent=false;
														break;

													case HttpHeaderValues.KEEP_ALIVE_ORDINAL:
														_persistent=true;
														break;

													case -1: // No match, may be multi valued
													{
														for (String v : value.toString().split(","))
														{
															switch(HttpHeaderValues.CACHE.getOrdinal(v.trim()))
															{
																case HttpHeaderValues.CLOSE_ORDINAL:
																	_persistent=false;
																	break;

																case HttpHeaderValues.KEEP_ALIVE_ORDINAL:
																	_persistent=true;
																	break;
															}
														}
														break;
													}
												}
										}
									}

									_handler.parsedHeader(header, value);
									_tok0.setPutIndex(_tok0.getIndex());
									_tok1.setPutIndex(_tok1.getIndex());
									_multiLineValue=null;
								}
								_buffer.setMarkIndex(-1);

								// now handle ch
								if (ch == HttpTokens.CARRIAGE_RETURN || ch == HttpTokens.LINE_FEED)
								{
									// is it a response that cannot have a body?
									if (_responseStatus > 0  && // response  
									   (_responseStatus == 304  || // not-modified response
										_responseStatus == 204 || // no-content response
										_responseStatus < 200)) // 1xx response
										_contentLength=HttpTokens.NO_CONTENT; // ignore any other headers set
									// else if we don't know framing
									else if (_contentLength == HttpTokens.UNKNOWN_CONTENT)
									{
										if (_responseStatus == 0  // request
												|| _responseStatus == 304 // not-modified response
												|| _responseStatus == 204 // no-content response
												|| _responseStatus < 200) // 1xx response
											_contentLength=HttpTokens.NO_CONTENT;
										else
											_contentLength=HttpTokens.EOF_CONTENT;
									}

									_contentPosition=0;
									_eol=ch;
									if (_eol==HttpTokens.CARRIAGE_RETURN && _buffer.hasContent() && _buffer.peek()==HttpTokens.LINE_FEED)
										_eol=_buffer.get();

									// We convert _contentLength to an int for this switch statement because
									// we don't care about the amount of data available just whether there is some.
									switch (_contentLength > Integer.MAX_VALUE ? Integer.MAX_VALUE : (int) _contentLength)
									{
										case HttpTokens.EOF_CONTENT:
											_state=STATE_EOF_CONTENT;
											_handler.headerComplete(); // May recurse here !
											break;

										case HttpTokens.CHUNKED_CONTENT:
											_state=STATE_CHUNKED_CONTENT;
											_handler.headerComplete(); // May recurse here !
											break;

										case HttpTokens.NO_CONTENT:
											_handler.headerComplete();
											_state=_persistent||(_responseStatus>=100&&_responseStatus<200)?STATE_END:STATE_SEEKING_EOF;
											_handler.messageComplete(_contentPosition);
											return 1;

										default:
											_state=STATE_CONTENT;
											_handler.headerComplete(); // May recurse here !
											break;
									}
									return 1;
								}
								else
								{
									// New header
									_length=1;
									_buffer.mark();
									_state=STATE_HEADER_NAME;

									// try cached name!
									if (array!=null)
									{
										_cached=HttpHeaders.CACHE.getBest(array, _buffer.markIndex(), length+1);

										if (_cached!=null)
										{
											_length=_cached.length();
											_buffer.setGetIndex(_buffer.markIndex()+_length);
											length=_buffer.length();
										}
									}
								}
							}
						}

						break;

					case STATE_HEADER_NAME:
						switch(ch)
						{
							case HttpTokens.CARRIAGE_RETURN:
							case HttpTokens.LINE_FEED:
								if (_length > 0)
									_tok0.update(_buffer.markIndex(), _buffer.markIndex() + _length);
								_eol=ch;
								_state=STATE_HEADER;
								break;
							case HttpTokens.COLON:
								if (_length > 0 && _cached==null)
									_tok0.update(_buffer.markIndex(), _buffer.markIndex() + _length);
								_length=-1;
								_state=STATE_HEADER_VALUE;
								break;
							case HttpTokens.SPACE:
							case HttpTokens.TAB:
								break;
							default:
							{
								_cached=null;
								if (_length == -1)
									_buffer.mark();
								_length=_buffer.getIndex() - _buffer.markIndex();
								_state=STATE_HEADER_IN_NAME;
							}
						}

						break;

					case STATE_HEADER_IN_NAME:
						switch(ch)
						{
							case HttpTokens.CARRIAGE_RETURN:
							case HttpTokens.LINE_FEED:
								if (_length > 0)
									_tok0.update(_buffer.markIndex(), _buffer.markIndex() + _length);
								_eol=ch;
								_state=STATE_HEADER;
								break;
							case HttpTokens.COLON:
								if (_length > 0 && _cached==null)
									_tok0.update(_buffer.markIndex(), _buffer.markIndex() + _length);
								_length=-1;
								_state=STATE_HEADER_VALUE;
								break;
							case HttpTokens.SPACE:
							case HttpTokens.TAB:
								_state=STATE_HEADER_NAME;
								break;
							default:
							{
								_cached=null;
								_length++;
							}
						}
						break;

					case STATE_HEADER_VALUE:
						switch(ch)
						{
							case HttpTokens.CARRIAGE_RETURN:
							case HttpTokens.LINE_FEED:
								if (_length > 0)
								{
									if (_tok1.length() == 0)
										_tok1.update(_buffer.markIndex(), _buffer.markIndex() + _length);
									else
									{
										// Continuation line!
										if (_multiLineValue == null) _multiLineValue=_tok1.toString(StringUtil.__ISO_8859_1);
										_tok1.update(_buffer.markIndex(), _buffer.markIndex() + _length);
										_multiLineValue += " " + _tok1.toString(StringUtil.__ISO_8859_1);
									}
								}
								_eol=ch;
								_state=STATE_HEADER;
								break;
							case HttpTokens.SPACE:
							case HttpTokens.TAB:
								break;
							default:
							{
								if (_length == -1)
									_buffer.mark();
								_length=_buffer.getIndex() - _buffer.markIndex();
								_state=STATE_HEADER_IN_VALUE;
							}
						}
						break;

					case STATE_HEADER_IN_VALUE:
						switch(ch)
						{
							case HttpTokens.CARRIAGE_RETURN:
							case HttpTokens.LINE_FEED:
								if (_length > 0)
								{
									if (_tok1.length() == 0)
										_tok1.update(_buffer.markIndex(), _buffer.markIndex() + _length);
									else
									{
										// Continuation line!
										if (_multiLineValue == null) _multiLineValue=_tok1.toString(StringUtil.__ISO_8859_1);
										_tok1.update(_buffer.markIndex(), _buffer.markIndex() + _length);
										_multiLineValue += " " + _tok1.toString(StringUtil.__ISO_8859_1);
									}
								}
								_eol=ch;
								_state=STATE_HEADER;
								break;
							case HttpTokens.SPACE:
							case HttpTokens.TAB:
								_state=STATE_HEADER_VALUE;
								break;
							default:
								_length++;
						}
						break;
				}
			} // end of HEADER states loop

			// ==========================

			// Handle HEAD response
			if (_responseStatus>0 && _headResponse)
			{
				_state=_persistent||(_responseStatus>=100&&_responseStatus<200)?STATE_END:STATE_SEEKING_EOF;
				_handler.messageComplete(_contentLength);
			}


			// ==========================

			// Handle _content
			length=_buffer.length();
			Buffer chunk;
			last=_state;
			while (_state > STATE_END && length > 0)
			{
				if (last!=_state)
				{
					progress++;
					last=_state;
				}

				if (_eol == HttpTokens.CARRIAGE_RETURN && _buffer.peek() == HttpTokens.LINE_FEED)
				{
					_eol=_buffer.get();
					length=_buffer.length();
					continue;
				}
				_eol=0;
				switch (_state)
				{
					case STATE_EOF_CONTENT:
						chunk=_buffer.get(_buffer.length());
						_contentPosition += chunk.length();
						_contentView.update(chunk);
						_handler.content(chunk); // May recurse here
						// TODO adjust the _buffer to keep unconsumed content
						return 1;

					case STATE_CONTENT:
					{
						long remaining=_contentLength - _contentPosition;
						if (remaining == 0)
						{
							_state=_persistent?STATE_END:STATE_SEEKING_EOF;
							_handler.messageComplete(_contentPosition);
							return 1;
						}

						if (length > remaining)
						{
							// We can cast reamining to an int as we know that it is smaller than
							// or equal to length which is already an int.
							length=(int)remaining;
						}

						chunk=_buffer.get(length);
						_contentPosition += chunk.length();
						_contentView.update(chunk);
						_handler.content(chunk); // May recurse here

						if(_contentPosition == _contentLength)
						{
							_state=_persistent?STATE_END:STATE_SEEKING_EOF;
							_handler.messageComplete(_contentPosition);
						}
						// TODO adjust the _buffer to keep unconsumed content
						return 1;
					}

					case STATE_CHUNKED_CONTENT:
					{
						ch=_buffer.peek();
						if (ch == HttpTokens.CARRIAGE_RETURN || ch == HttpTokens.LINE_FEED)
							_eol=_buffer.get();
						else if (ch <= HttpTokens.SPACE)
							_buffer.get();
						else
						{
							_chunkLength=0;
							_chunkPosition=0;
							_state=STATE_CHUNK_SIZE;
						}
						break;
					}

					case STATE_CHUNK_SIZE:
					{
						ch=_buffer.get();
						if (ch == HttpTokens.CARRIAGE_RETURN || ch == HttpTokens.LINE_FEED)
						{
							_eol=ch;

							if (_chunkLength == 0)
							{
								if (_eol==HttpTokens.CARRIAGE_RETURN && _buffer.hasContent() && _buffer.peek()==HttpTokens.LINE_FEED)
									_eol=_buffer.get();
								_state=_persistent?STATE_END:STATE_SEEKING_EOF;
								_handler.messageComplete(_contentPosition);
								return 1;
							}
							else
								_state=STATE_CHUNK;
						}
						else if (ch <= HttpTokens.SPACE || ch == HttpTokens.SEMI_COLON)
							_state=STATE_CHUNK_PARAMS;
						else if (ch >= '0' && ch <= '9')
							_chunkLength=_chunkLength * 16 + (ch - '0');
						else if (ch >= 'a' && ch <= 'f')
							_chunkLength=_chunkLength * 16 + (10 + ch - 'a');
						else if (ch >= 'A' && ch <= 'F')
							_chunkLength=_chunkLength * 16 + (10 + ch - 'A');
						else
							throw new IOException("bad chunk char: " + ch);
						break;
					}

					case STATE_CHUNK_PARAMS:
					{
						ch=_buffer.get();
						if (ch == HttpTokens.CARRIAGE_RETURN || ch == HttpTokens.LINE_FEED)
						{
							_eol=ch;
							if (_chunkLength == 0)
							{
								if (_eol==HttpTokens.CARRIAGE_RETURN && _buffer.hasContent() && _buffer.peek()==HttpTokens.LINE_FEED)
									_eol=_buffer.get();
								_state=_persistent?STATE_END:STATE_SEEKING_EOF;
								_handler.messageComplete(_contentPosition);
								return 1;
							}
							else
								_state=STATE_CHUNK;
						}
						break;
					}

					case STATE_CHUNK:
					{
						int remaining=_chunkLength - _chunkPosition;
						if (remaining == 0)
						{
							_state=STATE_CHUNKED_CONTENT;
							break;
						}
						else if (length > remaining)
							length=remaining;
						chunk=_buffer.get(length);
						_contentPosition += chunk.length();
						_chunkPosition += chunk.length();
						_contentView.update(chunk);
						_handler.content(chunk); // May recurse here
						// TODO adjust the _buffer to keep unconsumed content
						return 1;
					}

					case STATE_SEEKING_EOF:
					{                        
						// Close if there is more data than CRLF
						if (_buffer.length()>2)
						{
							_state=STATE_END;
							_endp.close();
						}
						else  
						{
							// or if the data is not white space
							while (_buffer.length()>0)
								if (!Character.isWhitespace(_buffer.get()))
								{
									_state=STATE_END;
									_endp.close();
									_buffer.clear();
								}
						}
						
						_buffer.clear();
						break;
					}
				}

				length=_buffer.length();
			}

			return progress;
		}
		catch(HttpException e)
		{
			_persistent=false;
			_state=STATE_SEEKING_EOF;
			throw e;
		}
	}

	/* ------------------------------------------------------------------------------- */
	/** fill the buffers from the endpoint
	 *
	 */
	private int fill() throws IOException
	{
		// Do we have a buffer?
		if (_buffer==null)
			_buffer=getHeaderBuffer();

		// Is there unconsumed content in body buffer
		if (_state>STATE_END && _buffer==_header && _header!=null && !_header.hasContent() && _body!=null && _body.hasContent())
		{
			_buffer=_body;
			return _buffer.length();
		}

		// Shall we switch to a body buffer?
		if (_buffer==_header && _state>STATE_END && _header.length()==0 && ((_contentLength-_contentPosition)>_header.capacity()) && (_body!=null||_buffers!=null))
		{
			if (_body==null)
				_body=_buffers.getBuffer();
			_buffer=_body;
		}

		// Shall we compact the body?
		if (_buffer==_body || _state>STATE_END)
		{
			_buffer.compact();
		}

		// Are we full?
		if (_buffer.space() == 0)
		{
			LOG.warn("HttpParser Full for {} ",_endp);
			_buffer.clear();
			throw new HttpException(HttpStatus.REQUEST_ENTITY_TOO_LARGE_413, "Request Entity Too Large: "+(_buffer==_body?"body":"head"));
		}
/* why?
		try
		{
			int filled = _endp.fill(_buffer);
			return filled;
		}
		catch(IOException e)
		{
			LOG.debug("",e);
			throw (e instanceof EofException) ? e:new EofException(e);
		}
*/
		return _endp.fill(_buffer);
	}

	public void reset()
	{
		// reset state
		_contentView.setGetIndex(_contentView.putIndex());
		_state=_persistent?STATE_START:(_endp.isInputShutdown()?STATE_END:STATE_SEEKING_EOF);
		_contentLength=HttpTokens.UNKNOWN_CONTENT;
		_contentPosition=0;
		_length=0;
		_responseStatus=0;

		// Consume LF if CRLF
		if (_eol == HttpTokens.CARRIAGE_RETURN && _buffer!=null && _buffer.hasContent() && _buffer.peek() == HttpTokens.LINE_FEED)
			_eol=_buffer.get();

		if (_body!=null && _body.hasContent())
		{
			// There is content in the body after the end of the request.
			// This is probably a pipelined header of the next request, so we need to
			// copy it to the header buffer.
			if (_header==null)
				getHeaderBuffer();
			else
			{
				_header.setMarkIndex(-1);
				_header.compact();
			}
			int take=_header.space();
			if (take>_body.length())
				take=_body.length();
			_body.peek(_body.getIndex(),take);
			_body.skip(_header.put(_body.peek(_body.getIndex(),take)));
		}

		if (_header!=null)
		{
			_header.setMarkIndex(-1);
			_header.compact();
		}
		if (_body!=null)
			_body.setMarkIndex(-1);

		_buffer=_header;
		returnBuffers();
	}


	public void returnBuffers()
	{
		if (_body!=null && !_body.hasContent() && _body.markIndex()==-1 && _buffers!=null)
		{
			if (_buffer==_body)
				_buffer=_header;
			if (_buffers!=null)
				_buffers.returnBuffer(_body);
			_body=null;
		}

		if (_header!=null && !_header.hasContent() && _header.markIndex()==-1 && _buffers!=null)
		{
			if (_buffer==_header)
				_buffer=null;
			_buffers.returnBuffer(_header);
			_header=null;
		}
	}

	@Override
	public String toString()
	{
		return String.format("%s{s=%d,l=%d,c=%d}",
				getClass().getSimpleName(),
				_state,
				_length,
				_contentLength);
	}

	public Buffer getHeaderBuffer()
	{
		if (_header == null)
		{
			_header = _buffers.getHeader();
			_tok0.update(_header);
			_tok1.update(_header);
		}
		return _header;
	}

	public Buffer blockForContent(long maxIdleTime) throws IOException
	{
		if (_contentView.length()>0)
			return _contentView;

		if (_state <= STATE_END || _state==STATE_SEEKING_EOF)
			return null;

		try
		{
			parseNext();

			// parse until some progress is made (or IOException thrown for timeout)
			while(_contentView.length() == 0 && !(_state==STATE_END||_state==STATE_SEEKING_EOF) && _endp.isOpen())
			{
				if (!_endp.isBlocking())
				{
					if (parseNext()>0)
						continue;

					if (!_endp.blockReadable(maxIdleTime))
					{
						_endp.close();
						throw new EofException("timeout");
					}
				}

				parseNext();
			}
		}
		catch(IOException e)
		{
			// TODO is this needed?
			_endp.close();
			throw e;
		}

		return _contentView.length()>0?_contentView:null;
	}

	/* ------------------------------------------------------------ */
	/* (non-Javadoc)
	 * @see java.io.InputStream#available()
	 */
	public int available() throws IOException
	{
		if (_contentView!=null && _contentView.length()>0)
			return _contentView.length();

		if (_endp.isBlocking())
		{
			return 0;
		}

		parseNext();
		return _contentView==null?0:_contentView.length();
	}


	public interface EventHandler
	{
		public abstract void content(Buffer ref) throws IOException;

		public void headerComplete() throws IOException;

		public void messageComplete(long contentLength) throws IOException;

		/**
		 * This is the method called by parser when a HTTP Header name and value is found
		 */
		public void parsedHeader(Buffer name, Buffer value) throws IOException;

		/**
		 * This is the method called by parser when the HTTP request line is parsed
		 */
		public abstract void startRequest(Buffer method, Buffer url, Buffer version)
				throws IOException;

		public void earlyEOF();
	}




}