1<?php
2
3declare(strict_types=1);
4
5namespace GuzzleHttp\Psr7;
6
7use Psr\Http\Message\MessageInterface;
8use Psr\Http\Message\StreamInterface;
9
10/**
11 * Trait implementing functionality common to requests and responses.
12 */
13trait MessageTrait
14{
15    /** @var string[][] Map of all registered headers, as original name => array of values */
16    private $headers = [];
17
18    /** @var string[] Map of lowercase header name => original name at registration */
19    private $headerNames = [];
20
21    /** @var string */
22    private $protocol = '1.1';
23
24    /** @var StreamInterface|null */
25    private $stream;
26
27    public function getProtocolVersion(): string
28    {
29        return $this->protocol;
30    }
31
32    public function withProtocolVersion($version): MessageInterface
33    {
34        if ($this->protocol === $version) {
35            return $this;
36        }
37
38        $new = clone $this;
39        $new->protocol = $version;
40
41        return $new;
42    }
43
44    public function getHeaders(): array
45    {
46        return $this->headers;
47    }
48
49    public function hasHeader($header): bool
50    {
51        return isset($this->headerNames[strtolower($header)]);
52    }
53
54    public function getHeader($header): array
55    {
56        $header = strtolower($header);
57
58        if (!isset($this->headerNames[$header])) {
59            return [];
60        }
61
62        $header = $this->headerNames[$header];
63
64        return $this->headers[$header];
65    }
66
67    public function getHeaderLine($header): string
68    {
69        return implode(', ', $this->getHeader($header));
70    }
71
72    public function withHeader($header, $value): MessageInterface
73    {
74        $this->assertHeader($header);
75        $value = $this->normalizeHeaderValue($value);
76        $normalized = strtolower($header);
77
78        $new = clone $this;
79        if (isset($new->headerNames[$normalized])) {
80            unset($new->headers[$new->headerNames[$normalized]]);
81        }
82        $new->headerNames[$normalized] = $header;
83        $new->headers[$header] = $value;
84
85        return $new;
86    }
87
88    public function withAddedHeader($header, $value): MessageInterface
89    {
90        $this->assertHeader($header);
91        $value = $this->normalizeHeaderValue($value);
92        $normalized = strtolower($header);
93
94        $new = clone $this;
95        if (isset($new->headerNames[$normalized])) {
96            $header = $this->headerNames[$normalized];
97            $new->headers[$header] = array_merge($this->headers[$header], $value);
98        } else {
99            $new->headerNames[$normalized] = $header;
100            $new->headers[$header] = $value;
101        }
102
103        return $new;
104    }
105
106    public function withoutHeader($header): MessageInterface
107    {
108        $normalized = strtolower($header);
109
110        if (!isset($this->headerNames[$normalized])) {
111            return $this;
112        }
113
114        $header = $this->headerNames[$normalized];
115
116        $new = clone $this;
117        unset($new->headers[$header], $new->headerNames[$normalized]);
118
119        return $new;
120    }
121
122    public function getBody(): StreamInterface
123    {
124        if (!$this->stream) {
125            $this->stream = Utils::streamFor('');
126        }
127
128        return $this->stream;
129    }
130
131    public function withBody(StreamInterface $body): MessageInterface
132    {
133        if ($body === $this->stream) {
134            return $this;
135        }
136
137        $new = clone $this;
138        $new->stream = $body;
139
140        return $new;
141    }
142
143    /**
144     * @param (string|string[])[] $headers
145     */
146    private function setHeaders(array $headers): void
147    {
148        $this->headerNames = $this->headers = [];
149        foreach ($headers as $header => $value) {
150            // Numeric array keys are converted to int by PHP.
151            $header = (string) $header;
152
153            $this->assertHeader($header);
154            $value = $this->normalizeHeaderValue($value);
155            $normalized = strtolower($header);
156            if (isset($this->headerNames[$normalized])) {
157                $header = $this->headerNames[$normalized];
158                $this->headers[$header] = array_merge($this->headers[$header], $value);
159            } else {
160                $this->headerNames[$normalized] = $header;
161                $this->headers[$header] = $value;
162            }
163        }
164    }
165
166    /**
167     * @param mixed $value
168     *
169     * @return string[]
170     */
171    private function normalizeHeaderValue($value): array
172    {
173        if (!is_array($value)) {
174            return $this->trimAndValidateHeaderValues([$value]);
175        }
176
177        if (count($value) === 0) {
178            throw new \InvalidArgumentException('Header value can not be an empty array.');
179        }
180
181        return $this->trimAndValidateHeaderValues($value);
182    }
183
184    /**
185     * Trims whitespace from the header values.
186     *
187     * Spaces and tabs ought to be excluded by parsers when extracting the field value from a header field.
188     *
189     * header-field = field-name ":" OWS field-value OWS
190     * OWS          = *( SP / HTAB )
191     *
192     * @param mixed[] $values Header values
193     *
194     * @return string[] Trimmed header values
195     *
196     * @see https://datatracker.ietf.org/doc/html/rfc7230#section-3.2.4
197     */
198    private function trimAndValidateHeaderValues(array $values): array
199    {
200        return array_map(function ($value) {
201            if (!is_scalar($value) && null !== $value) {
202                throw new \InvalidArgumentException(sprintf(
203                    'Header value must be scalar or null but %s provided.',
204                    is_object($value) ? get_class($value) : gettype($value)
205                ));
206            }
207
208            $trimmed = trim((string) $value, " \t");
209            $this->assertValue($trimmed);
210
211            return $trimmed;
212        }, array_values($values));
213    }
214
215    /**
216     * @see https://datatracker.ietf.org/doc/html/rfc7230#section-3.2
217     *
218     * @param mixed $header
219     */
220    private function assertHeader($header): void
221    {
222        if (!is_string($header)) {
223            throw new \InvalidArgumentException(sprintf(
224                'Header name must be a string but %s provided.',
225                is_object($header) ? get_class($header) : gettype($header)
226            ));
227        }
228
229        if (!preg_match('/^[a-zA-Z0-9\'`#$%&*+.^_|~!-]+$/D', $header)) {
230            throw new \InvalidArgumentException(
231                sprintf('"%s" is not valid header name.', $header)
232            );
233        }
234    }
235
236    /**
237     * @see https://datatracker.ietf.org/doc/html/rfc7230#section-3.2
238     *
239     * field-value    = *( field-content / obs-fold )
240     * field-content  = field-vchar [ 1*( SP / HTAB ) field-vchar ]
241     * field-vchar    = VCHAR / obs-text
242     * VCHAR          = %x21-7E
243     * obs-text       = %x80-FF
244     * obs-fold       = CRLF 1*( SP / HTAB )
245     */
246    private function assertValue(string $value): void
247    {
248        // The regular expression intentionally does not support the obs-fold production, because as
249        // per RFC 7230#3.2.4:
250        //
251        // A sender MUST NOT generate a message that includes
252        // line folding (i.e., that has any field-value that contains a match to
253        // the obs-fold rule) unless the message is intended for packaging
254        // within the message/http media type.
255        //
256        // Clients must not send a request with line folding and a server sending folded headers is
257        // likely very rare. Line folding is a fairly obscure feature of HTTP/1.1 and thus not accepting
258        // folding is not likely to break any legitimate use case.
259        if (!preg_match('/^[\x20\x09\x21-\x7E\x80-\xFF]*$/D', $value)) {
260            throw new \InvalidArgumentException(
261                sprintf('"%s" is not valid header value.', $value)
262            );
263        }
264    }
265}
266