summaryrefslogtreecommitdiff
path: root/program/lib/Roundcube/rcube_string_replacer.php
blob: ca4fdfcfc3da01f1e15e28c6807c043c73d163a9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
<?php

/*
 +-----------------------------------------------------------------------+
 | This file is part of the Roundcube Webmail client                     |
 | Copyright (C) 2009-2012, The Roundcube Dev Team                       |
 |                                                                       |
 | Licensed under the GNU General Public License version 3 or            |
 | any later version with exceptions for skins & plugins.                |
 | See the README file for a full license statement.                     |
 |                                                                       |
 | PURPOSE:                                                              |
 |   Handle string replacements based on preg_replace_callback           |
 +-----------------------------------------------------------------------+
 | Author: Thomas Bruederli <roundcube@gmail.com>                        |
 +-----------------------------------------------------------------------+
*/

/**
 * Helper class for string replacements based on preg_replace_callback
 *
 * @package    Framework
 * @subpackage Utils
 */
class rcube_string_replacer
{
    public static $pattern = '/##str_replacement\{([0-9]+)\}##/';
    public $mailto_pattern;
    public $link_pattern;

    private $values = array();
    private $options = array();
    private $linkrefs = array();
    private $urls = array();


    function __construct($options = array())
    {
        // Simplified domain expression for UTF8 characters handling
        // Support unicode/punycode in top-level domain part
        $utf_domain = '[^?&@"\'\\/()<>\s\r\t\n]+\\.?([^\\x00-\\x2f\\x3b-\\x40\\x5b-\\x60\\x7b-\\x7f]{2,}|xn--[a-zA-Z0-9]{2,})';
        $url1       = '.:;,';
        $url2       = 'a-zA-Z0-9%=#$@+?|!&\\/_~\\[\\]\\(\\){}\*-';

        $this->link_pattern = "/([\w]+:\/\/|\W[Ww][Ww][Ww]\.|^[Ww][Ww][Ww]\.)($utf_domain([$url1]*[$url2]+)*)/";
        $this->mailto_pattern = "/("
            ."[-\w!\#\$%&\'*+~\/^`|{}=]+(?:\.[-\w!\#\$%&\'*+~\/^`|{}=]+)*"  // local-part
            ."@$utf_domain"                                                 // domain-part
            ."(\?[$url1$url2]+)?"                                           // e.g. ?subject=test...
            .")/";
        $this->linkref_index = '/\[([a-zA-Z0-9]+)\]:?\s*##str_replacement\{(\d+)\}##/';
        $this->linkref_pattern = '/\[([a-zA-Z0-9]+)\]/';

        $this->options = $options;
    }

    /**
     * Add a string to the internal list
     *
     * @param string String value 
     * @return int Index of value for retrieval
     */
    public function add($str)
    {
        $i = count($this->values);
        $this->values[$i] = $str;
        return $i;
    }

    /**
     * Build replacement string
     */
    public function get_replacement($i)
    {
        return '##str_replacement{'.$i.'}##';
    }

    /**
     * Callback function used to build HTML links around URL strings
     *
     * @param array Matches result from preg_replace_callback
     * @return int Index of saved string value
     */
    public function link_callback($matches)
    {
        $i = -1;
        $scheme = strtolower($matches[1]);

        if (preg_match('!^(http|ftp|file)s?://!i', $scheme)) {
            $url = $matches[1] . $matches[2];
        }
        else if (preg_match('/^(\W*)(www\.)$/i', $matches[1], $m)) {
            $url        = $m[2] . $matches[2];
            $url_prefix = 'http://';
            $prefix     = $m[1];
        }

        if ($url) {
            $suffix = $this->parse_url_brackets($url);
            $attrib = (array)$this->options['link_attribs'];
            $attrib['href'] = $url_prefix . $url;

            $i = $this->add(html::a($attrib, rcube::Q($url)) . $suffix);
            $this->urls[$i] = $attrib['href'];
        }

        // Return valid link for recognized schemes, otherwise
        // return the unmodified string for unrecognized schemes.
        return $i >= 0 ? $prefix . $this->get_replacement($i) : $matches[0];
    }

    /**
     * Callback to add an entry to the link index
     */
    public function linkref_addindex($matches)
    {
        $key = $matches[1];
        $this->linkrefs[$key] = $matches[2];

        return $matches[0];
    }

    /**
     * Callback to replace link references with real links
     */
    public function linkref_callback($matches)
    {
        $i = 0;
        $key = isset($this->linkrefs[$matches[1]]) ? $this->linkrefs[$matches[1]] : '-';
        if ($url = $this->urls[$key]) {
            $attrib = (array)$this->options['link_attribs'];
            $attrib['href'] = $url;
            $i = $this->add(html::a($attrib, rcube::Q($matches[1])));
        }

        return $i > 0 ? '['.$this->get_replacement($i).']' : $matches[0];
    }

    /**
     * Callback function used to build mailto: links around e-mail strings
     *
     * @param array Matches result from preg_replace_callback
     * @return int Index of saved string value
     */
    public function mailto_callback($matches)
    {
        $href   = $matches[1];
        $suffix = $this->parse_url_brackets($href);
        $i = $this->add(html::a('mailto:' . $href, rcube::Q($href)) . $suffix);

        return $i >= 0 ? $this->get_replacement($i) : '';
    }

    /**
     * Look up the index from the preg_replace matches array
     * and return the substitution value.
     *
     * @param array Matches result from preg_replace_callback
     * @return string Value at index $matches[1]
     */
    public function replace_callback($matches)
    {
        return $this->values[$matches[1]];
    }

    /**
     * Replace all defined (link|mailto) patterns with replacement string
     *
     * @param string $str Text
     *
     * @return string Text
     */
    public function replace($str)
    {
        // search for patterns like links and e-mail addresses
        $str = preg_replace_callback($this->link_pattern, array($this, 'link_callback'), $str);
        $str = preg_replace_callback($this->mailto_pattern, array($this, 'mailto_callback'), $str);
        // resolve link references
        $str = preg_replace_callback($this->linkref_index, array($this, 'linkref_addindex'), $str);
        $str = preg_replace_callback($this->linkref_pattern, array($this, 'linkref_callback'), $str);

        return $str;
    }

    /**
     * Replace substituted strings with original values
     */
    public function resolve($str)
    {
        return preg_replace_callback(self::$pattern, array($this, 'replace_callback'), $str);
    }

    /**
     * Fixes bracket characters in URL handling
     */
    public static function parse_url_brackets(&$url)
    {
        // #1487672: special handling of square brackets,
        // URL regexp allows [] characters in URL, for example:
        // "http://example.com/?a[b]=c". However we need to handle
        // properly situation when a bracket is placed at the end
        // of the link e.g. "[http://example.com]"
        // Yes, this is not perfect handles correctly only paired characters
        // but it should work for common cases

        if (preg_match('/(\\[|\\])/', $url)) {
            $in = false;
            for ($i=0, $len=strlen($url); $i<$len; $i++) {
                if ($url[$i] == '[') {
                    if ($in)
                        break;
                    $in = true;
                }
                else if ($url[$i] == ']') {
                    if (!$in)
                        break;
                    $in = false;
                }
            }

            if ($i < $len) {
                $suffix = substr($url, $i);
                $url    = substr($url, 0, $i);
            }
        }

        // Do the same for parentheses
        if (preg_match('/(\\(|\\))/', $url)) {
            $in = false;
            for ($i=0, $len=strlen($url); $i<$len; $i++) {
                if ($url[$i] == '(') {
                    if ($in)
                        break;
                    $in = true;
                }
                else if ($url[$i] == ')') {
                    if (!$in)
                        break;
                    $in = false;
                }
            }

            if ($i < $len) {
                $suffix = substr($url, $i);
                $url    = substr($url, 0, $i);
            }
        }

        return $suffix;
    }
}