1<?php
2
3/*
4 * This file is part of SwiftMailer.
5 * (c) 2004-2009 Chris Corbyn
6 *
7 * For the full copyright and license information, please view the LICENSE
8 * file that was distributed with this source code.
9 */
10
11/**
12 * Handles RFC 2231 specified Encoding in Swift Mailer.
13 *
14 * @author Chris Corbyn
15 */
16class Swift_Encoder_Rfc2231Encoder implements Swift_Encoder
17{
18    /**
19     * A character stream to use when reading a string as characters instead of bytes.
20     *
21     * @var Swift_CharacterStream
22     */
23    private $_charStream;
24
25    /**
26     * Creates a new Rfc2231Encoder using the given character stream instance.
27     *
28     * @param Swift_CharacterStream
29     */
30    public function __construct(Swift_CharacterStream $charStream)
31    {
32        $this->_charStream = $charStream;
33    }
34
35    /**
36     * Takes an unencoded string and produces a string encoded according to
37     * RFC 2231 from it.
38     *
39     * @param string $string
40     * @param int    $firstLineOffset
41     * @param int    $maxLineLength   optional, 0 indicates the default of 75 bytes
42     *
43     * @return string
44     */
45    public function encodeString($string, $firstLineOffset = 0, $maxLineLength = 0)
46    {
47        $lines = array();
48        $lineCount = 0;
49        $lines[] = '';
50        $currentLine = &$lines[$lineCount++];
51
52        if (0 >= $maxLineLength) {
53            $maxLineLength = 75;
54        }
55
56        $this->_charStream->flushContents();
57        $this->_charStream->importString($string);
58
59        $thisLineLength = $maxLineLength - $firstLineOffset;
60
61        while (false !== $char = $this->_charStream->read(4)) {
62            $encodedChar = rawurlencode($char);
63            if (0 != strlen($currentLine)
64                && strlen($currentLine.$encodedChar) > $thisLineLength) {
65                $lines[] = '';
66                $currentLine = &$lines[$lineCount++];
67                $thisLineLength = $maxLineLength;
68            }
69            $currentLine .= $encodedChar;
70        }
71
72        return implode("\r\n", $lines);
73    }
74
75    /**
76     * Updates the charset used.
77     *
78     * @param string $charset
79     */
80    public function charsetChanged($charset)
81    {
82        $this->_charStream->setCharacterSet($charset);
83    }
84
85    /**
86     * Make a deep copy of object.
87     */
88    public function __clone()
89    {
90        $this->_charStream = clone $this->_charStream;
91    }
92}
93