1<?php
2
3/*
4 * This file is part of the Symfony package.
5 *
6 * (c) Fabien Potencier <fabien@symfony.com>
7 *
8 * For the full copyright and license information, please view the LICENSE
9 * file that was distributed with this source code.
10 */
11
12namespace Symfony\Component\Intl\Util;
13
14/**
15 * Facilitates the comparison of version strings.
16 *
17 * @author Bernhard Schussek <bschussek@gmail.com>
18 */
19class Version
20{
21    /**
22     * Compares two versions with an operator.
23     *
24     * This method is identical to {@link version_compare()}, except that you
25     * can pass the number of regarded version components in the last argument
26     * $precision.
27     *
28     * Examples:
29     *
30     *     Version::compare('1.2.3', '1.2.4', '==')
31     *     // => false
32     *
33     *     Version::compare('1.2.3', '1.2.4', '==', 2)
34     *     // => true
35     *
36     * @param int|null $precision The number of components to compare. Pass
37     *                            NULL to compare the versions unchanged.
38     *
39     * @return bool Whether the comparison succeeded
40     *
41     * @see normalize()
42     */
43    public static function compare(string $version1, string $version2, string $operator, ?int $precision = null)
44    {
45        $version1 = self::normalize($version1, $precision);
46        $version2 = self::normalize($version2, $precision);
47
48        return version_compare($version1, $version2, $operator);
49    }
50
51    /**
52     * Normalizes a version string to the number of components given in the
53     * parameter $precision.
54     *
55     * Examples:
56     *
57     *     Version::normalize('1.2.3', 1);
58     *     // => '1'
59     *
60     *     Version::normalize('1.2.3', 2);
61     *     // => '1.2'
62     *
63     * @param int|null $precision The number of components to include. Pass
64     *                            NULL to return the version unchanged.
65     *
66     * @return string|null the normalized version or NULL if it couldn't be
67     *                     normalized
68     */
69    public static function normalize(string $version, ?int $precision)
70    {
71        if (null === $precision) {
72            return $version;
73        }
74
75        $pattern = '[^\.]+';
76
77        for ($i = 2; $i <= $precision; ++$i) {
78            $pattern = sprintf('[^\.]+(\.%s)?', $pattern);
79        }
80
81        if (!preg_match('/^'.$pattern.'/', $version, $matches)) {
82            return null;
83        }
84
85        return $matches[0];
86    }
87
88    /**
89     * Must not be instantiated.
90     */
91    private function __construct()
92    {
93    }
94}
95