<?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.
 */

//@require 'Swift/StreamFilter.php';

/**
 * Processes bytes as they pass through a buffer and replaces sequences in it.
 * @package Swift
 * @author Chris Corbyn
 */
class Swift_StreamFilters_StringReplacementFilter implements Swift_StreamFilter
{
  
  /** The needle(s) to search for */
  private $_search;
  
  /** The replacement(s) to make */
  private $_replace;
  
  /**
   * Create a new StringReplacementFilter with $search and $replace.
   * @param string|array $search
   * @param string|array $replace
   */
  public function __construct($search, $replace)
  {
    $this->_search = $search;
    $this->_replace = $replace;
  }
  
  /**
   * Returns true if based on the buffer passed more bytes should be buffered.
   * @param string $buffer
   * @return boolean
   */
  public function shouldBuffer($buffer)
  {
    $endOfBuffer = substr($buffer, -1);
    foreach ((array) $this->_search as $needle)
    {
      if (false !== strpos($needle, $endOfBuffer))
      {
        return true;
      }
    }
    return false;
  }
  
  /**
   * Perform the actual replacements on $buffer and return the result.
   * @param string $buffer
   * @return string
   */
  public function filter($buffer)
  {
    return str_replace($this->_search, $this->_replace, $buffer);
  }
  
}
