1<?php
2
3/**
4 * Validates shorthand CSS property background.
5 * @warning Does not support url tokens that have internal spaces.
6 */
7class HTMLPurifier_AttrDef_CSS_Background extends HTMLPurifier_AttrDef
8{
9
10    /**
11     * Local copy of component validators.
12     * @type HTMLPurifier_AttrDef[]
13     * @note See HTMLPurifier_AttrDef_Font::$info for a similar impl.
14     */
15    protected $info;
16
17    /**
18     * @param HTMLPurifier_Config $config
19     */
20    public function __construct($config)
21    {
22        $def = $config->getCSSDefinition();
23        $this->info['background-color'] = $def->info['background-color'];
24        $this->info['background-image'] = $def->info['background-image'];
25        $this->info['background-repeat'] = $def->info['background-repeat'];
26        $this->info['background-attachment'] = $def->info['background-attachment'];
27        $this->info['background-position'] = $def->info['background-position'];
28    }
29
30    /**
31     * @param string $string
32     * @param HTMLPurifier_Config $config
33     * @param HTMLPurifier_Context $context
34     * @return bool|string
35     */
36    public function validate($string, $config, $context)
37    {
38        // regular pre-processing
39        $string = $this->parseCDATA($string);
40        if ($string === '') {
41            return false;
42        }
43
44        // munge rgb() decl if necessary
45        $string = $this->mungeRgb($string);
46
47        // assumes URI doesn't have spaces in it
48        $bits = explode(' ', $string); // bits to process
49
50        $caught = array();
51        $caught['color'] = false;
52        $caught['image'] = false;
53        $caught['repeat'] = false;
54        $caught['attachment'] = false;
55        $caught['position'] = false;
56
57        $i = 0; // number of catches
58
59        foreach ($bits as $bit) {
60            if ($bit === '') {
61                continue;
62            }
63            foreach ($caught as $key => $status) {
64                if ($key != 'position') {
65                    if ($status !== false) {
66                        continue;
67                    }
68                    $r = $this->info['background-' . $key]->validate($bit, $config, $context);
69                } else {
70                    $r = $bit;
71                }
72                if ($r === false) {
73                    continue;
74                }
75                if ($key == 'position') {
76                    if ($caught[$key] === false) {
77                        $caught[$key] = '';
78                    }
79                    $caught[$key] .= $r . ' ';
80                } else {
81                    $caught[$key] = $r;
82                }
83                $i++;
84                break;
85            }
86        }
87
88        if (!$i) {
89            return false;
90        }
91        if ($caught['position'] !== false) {
92            $caught['position'] = $this->info['background-position']->
93                validate($caught['position'], $config, $context);
94        }
95
96        $ret = array();
97        foreach ($caught as $value) {
98            if ($value === false) {
99                continue;
100            }
101            $ret[] = $value;
102        }
103
104        if (empty($ret)) {
105            return false;
106        }
107        return implode(' ', $ret);
108    }
109}
110
111// vim: et sw=4 sts=4
112