1<?php
2
3declare(strict_types=1);
4
5namespace GuzzleHttp\Psr7;
6
7final class Header
8{
9    /**
10     * Parse an array of header values containing ";" separated data into an
11     * array of associative arrays representing the header key value pair data
12     * of the header. When a parameter does not contain a value, but just
13     * contains a key, this function will inject a key with a '' string value.
14     *
15     * @param string|array $header Header to parse into components.
16     */
17    public static function parse($header): array
18    {
19        static $trimmed = "\"'  \n\t\r";
20        $params = $matches = [];
21
22        foreach ((array) $header as $value) {
23            foreach (self::splitList($value) as $val) {
24                $part = [];
25                foreach (preg_split('/;(?=([^"]*"[^"]*")*[^"]*$)/', $val) ?: [] as $kvp) {
26                    if (preg_match_all('/<[^>]+>|[^=]+/', $kvp, $matches)) {
27                        $m = $matches[0];
28                        if (isset($m[1])) {
29                            $part[trim($m[0], $trimmed)] = trim($m[1], $trimmed);
30                        } else {
31                            $part[] = trim($m[0], $trimmed);
32                        }
33                    }
34                }
35                if ($part) {
36                    $params[] = $part;
37                }
38            }
39        }
40
41        return $params;
42    }
43
44    /**
45     * Converts an array of header values that may contain comma separated
46     * headers into an array of headers with no comma separated values.
47     *
48     * @param string|array $header Header to normalize.
49     *
50     * @deprecated Use self::splitList() instead.
51     */
52    public static function normalize($header): array
53    {
54        $result = [];
55        foreach ((array) $header as $value) {
56            foreach (self::splitList($value) as $parsed) {
57                $result[] = $parsed;
58            }
59        }
60
61        return $result;
62    }
63
64    /**
65     * Splits a HTTP header defined to contain a comma-separated list into
66     * each individual value. Empty values will be removed.
67     *
68     * Example headers include 'accept', 'cache-control' and 'if-none-match'.
69     *
70     * This method must not be used to parse headers that are not defined as
71     * a list, such as 'user-agent' or 'set-cookie'.
72     *
73     * @param string|string[] $values Header value as returned by MessageInterface::getHeader()
74     *
75     * @return string[]
76     */
77    public static function splitList($values): array
78    {
79        if (!\is_array($values)) {
80            $values = [$values];
81        }
82
83        $result = [];
84        foreach ($values as $value) {
85            if (!\is_string($value)) {
86                throw new \TypeError('$header must either be a string or an array containing strings.');
87            }
88
89            $v = '';
90            $isQuoted = false;
91            $isEscaped = false;
92            for ($i = 0, $max = \strlen($value); $i < $max; ++$i) {
93                if ($isEscaped) {
94                    $v .= $value[$i];
95                    $isEscaped = false;
96
97                    continue;
98                }
99
100                if (!$isQuoted && $value[$i] === ',') {
101                    $v = \trim($v);
102                    if ($v !== '') {
103                        $result[] = $v;
104                    }
105
106                    $v = '';
107                    continue;
108                }
109
110                if ($isQuoted && $value[$i] === '\\') {
111                    $isEscaped = true;
112                    $v .= $value[$i];
113
114                    continue;
115                }
116                if ($value[$i] === '"') {
117                    $isQuoted = !$isQuoted;
118                    $v .= $value[$i];
119
120                    continue;
121                }
122
123                $v .= $value[$i];
124            }
125
126            $v = \trim($v);
127            if ($v !== '') {
128                $result[] = $v;
129            }
130        }
131
132        return $result;
133    }
134}
135