<?php

/*
 * This file is part of SwiftMailer.
 * (c) 2004-2009 Chris Corbyn
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

/**
 * Analyzes characters for a specific character set.
 * @package Swift
 * @subpackage Encoder
 * @author Chris Corbyn
 * @author Xavier De Cock <xdecock@gmail.com>
 */
interface Swift_CharacterReader
{
  const MAP_TYPE_INVALID = 0x01;
  const MAP_TYPE_FIXED_LEN = 0x02;
  const MAP_TYPE_POSITIONS = 0x03;
  
  /**
   * Returns the complete charactermap
   *
   * @param string $string
   * @param int $startOffset
   * @param array $currentMap
   * @param mixed $ignoredChars
   * @return int
   */
  public function getCharPositions($string, $startOffset, &$currentMap, &$ignoredChars);
  
  /**
   * Returns mapType
   * @int mapType
   */
  public function getMapType();
  
  /**
   * Returns an integer which specifies how many more bytes to read.
   * A positive integer indicates the number of more bytes to fetch before invoking
   * this method again.
   * A value of zero means this is already a valid character.
   * A value of -1 means this cannot possibly be a valid character.
   * @param int[] $bytes
   * @return int
   */
  public function validateByteSequence($bytes, $size);

  /**
   * Returns the number of bytes which should be read to start each character.
   * For fixed width character sets this should be the number of
   * octets-per-character. For multibyte character sets this will probably be 1.
   * @return int
   */
  public function getInitialByteSize();

}
