1<?php
2
3/**
4 * Validates an integer.
5 * @note While this class was modeled off the CSS definition, no currently
6 *       allowed CSS uses this type.  The properties that do are: widows,
7 *       orphans, z-index, counter-increment, counter-reset.  Some of the
8 *       HTML attributes, however, find use for a non-negative version of this.
9 */
10class HTMLPurifier_AttrDef_Integer extends HTMLPurifier_AttrDef
11{
12
13    /**
14     * Whether or not negative values are allowed.
15     * @type bool
16     */
17    protected $negative = true;
18
19    /**
20     * Whether or not zero is allowed.
21     * @type bool
22     */
23    protected $zero = true;
24
25    /**
26     * Whether or not positive values are allowed.
27     * @type bool
28     */
29    protected $positive = true;
30
31    /**
32     * @param $negative Bool indicating whether or not negative values are allowed
33     * @param $zero Bool indicating whether or not zero is allowed
34     * @param $positive Bool indicating whether or not positive values are allowed
35     */
36    public function __construct($negative = true, $zero = true, $positive = true)
37    {
38        $this->negative = $negative;
39        $this->zero = $zero;
40        $this->positive = $positive;
41    }
42
43    /**
44     * @param string $integer
45     * @param HTMLPurifier_Config $config
46     * @param HTMLPurifier_Context $context
47     * @return bool|string
48     */
49    public function validate($integer, $config, $context)
50    {
51        $integer = $this->parseCDATA($integer);
52        if ($integer === '') {
53            return false;
54        }
55
56        // we could possibly simply typecast it to integer, but there are
57        // certain fringe cases that must not return an integer.
58
59        // clip leading sign
60        if ($this->negative && $integer[0] === '-') {
61            $digits = substr($integer, 1);
62            if ($digits === '0') {
63                $integer = '0';
64            } // rm minus sign for zero
65        } elseif ($this->positive && $integer[0] === '+') {
66            $digits = $integer = substr($integer, 1); // rm unnecessary plus
67        } else {
68            $digits = $integer;
69        }
70
71        // test if it's numeric
72        if (!ctype_digit($digits)) {
73            return false;
74        }
75
76        // perform scope tests
77        if (!$this->zero && $integer == 0) {
78            return false;
79        }
80        if (!$this->positive && $integer > 0) {
81            return false;
82        }
83        if (!$this->negative && $integer < 0) {
84            return false;
85        }
86
87        return $integer;
88    }
89}
90
91// vim: et sw=4 sts=4
92