1<?php
2
3declare(strict_types=1);
4
5namespace GuzzleHttp\Psr7;
6
7use Psr\Http\Message\MessageInterface;
8use Psr\Http\Message\RequestInterface;
9use Psr\Http\Message\ResponseInterface;
10
11final class Message
12{
13    /**
14     * Returns the string representation of an HTTP message.
15     *
16     * @param MessageInterface $message Message to convert to a string.
17     */
18    public static function toString(MessageInterface $message): string
19    {
20        if ($message instanceof RequestInterface) {
21            $msg = trim($message->getMethod().' '
22                    .$message->getRequestTarget())
23                .' HTTP/'.$message->getProtocolVersion();
24            if (!$message->hasHeader('host')) {
25                $msg .= "\r\nHost: ".$message->getUri()->getHost();
26            }
27        } elseif ($message instanceof ResponseInterface) {
28            $msg = 'HTTP/'.$message->getProtocolVersion().' '
29                .$message->getStatusCode().' '
30                .$message->getReasonPhrase();
31        } else {
32            throw new \InvalidArgumentException('Unknown message type');
33        }
34
35        foreach ($message->getHeaders() as $name => $values) {
36            if (is_string($name) && strtolower($name) === 'set-cookie') {
37                foreach ($values as $value) {
38                    $msg .= "\r\n{$name}: ".$value;
39                }
40            } else {
41                $msg .= "\r\n{$name}: ".implode(', ', $values);
42            }
43        }
44
45        return "{$msg}\r\n\r\n".$message->getBody();
46    }
47
48    /**
49     * Get a short summary of the message body.
50     *
51     * Will return `null` if the response is not printable.
52     *
53     * @param MessageInterface $message    The message to get the body summary
54     * @param int              $truncateAt The maximum allowed size of the summary
55     */
56    public static function bodySummary(MessageInterface $message, int $truncateAt = 120): ?string
57    {
58        $body = $message->getBody();
59
60        if (!$body->isSeekable() || !$body->isReadable()) {
61            return null;
62        }
63
64        $size = $body->getSize();
65
66        if ($size === 0) {
67            return null;
68        }
69
70        $body->rewind();
71        $summary = $body->read($truncateAt);
72        $body->rewind();
73
74        if ($size > $truncateAt) {
75            $summary .= ' (truncated...)';
76        }
77
78        // Matches any printable character, including unicode characters:
79        // letters, marks, numbers, punctuation, spacing, and separators.
80        if (preg_match('/[^\pL\pM\pN\pP\pS\pZ\n\r\t]/u', $summary) !== 0) {
81            return null;
82        }
83
84        return $summary;
85    }
86
87    /**
88     * Attempts to rewind a message body and throws an exception on failure.
89     *
90     * The body of the message will only be rewound if a call to `tell()`
91     * returns a value other than `0`.
92     *
93     * @param MessageInterface $message Message to rewind
94     *
95     * @throws \RuntimeException
96     */
97    public static function rewindBody(MessageInterface $message): void
98    {
99        $body = $message->getBody();
100
101        if ($body->tell()) {
102            $body->rewind();
103        }
104    }
105
106    /**
107     * Parses an HTTP message into an associative array.
108     *
109     * The array contains the "start-line" key containing the start line of
110     * the message, "headers" key containing an associative array of header
111     * array values, and a "body" key containing the body of the message.
112     *
113     * @param string $message HTTP request or response to parse.
114     */
115    public static function parseMessage(string $message): array
116    {
117        if (!$message) {
118            throw new \InvalidArgumentException('Invalid message');
119        }
120
121        $message = ltrim($message, "\r\n");
122
123        $messageParts = preg_split("/\r?\n\r?\n/", $message, 2);
124
125        if ($messageParts === false || count($messageParts) !== 2) {
126            throw new \InvalidArgumentException('Invalid message: Missing header delimiter');
127        }
128
129        [$rawHeaders, $body] = $messageParts;
130        $rawHeaders .= "\r\n"; // Put back the delimiter we split previously
131        $headerParts = preg_split("/\r?\n/", $rawHeaders, 2);
132
133        if ($headerParts === false || count($headerParts) !== 2) {
134            throw new \InvalidArgumentException('Invalid message: Missing status line');
135        }
136
137        [$startLine, $rawHeaders] = $headerParts;
138
139        if (preg_match("/(?:^HTTP\/|^[A-Z]+ \S+ HTTP\/)(\d+(?:\.\d+)?)/i", $startLine, $matches) && $matches[1] === '1.0') {
140            // Header folding is deprecated for HTTP/1.1, but allowed in HTTP/1.0
141            $rawHeaders = preg_replace(Rfc7230::HEADER_FOLD_REGEX, ' ', $rawHeaders);
142        }
143
144        /** @var array[] $headerLines */
145        $count = preg_match_all(Rfc7230::HEADER_REGEX, $rawHeaders, $headerLines, PREG_SET_ORDER);
146
147        // If these aren't the same, then one line didn't match and there's an invalid header.
148        if ($count !== substr_count($rawHeaders, "\n")) {
149            // Folding is deprecated, see https://datatracker.ietf.org/doc/html/rfc7230#section-3.2.4
150            if (preg_match(Rfc7230::HEADER_FOLD_REGEX, $rawHeaders)) {
151                throw new \InvalidArgumentException('Invalid header syntax: Obsolete line folding');
152            }
153
154            throw new \InvalidArgumentException('Invalid header syntax');
155        }
156
157        $headers = [];
158
159        foreach ($headerLines as $headerLine) {
160            $headers[$headerLine[1]][] = $headerLine[2];
161        }
162
163        return [
164            'start-line' => $startLine,
165            'headers' => $headers,
166            'body' => $body,
167        ];
168    }
169
170    /**
171     * Constructs a URI for an HTTP request message.
172     *
173     * @param string $path    Path from the start-line
174     * @param array  $headers Array of headers (each value an array).
175     */
176    public static function parseRequestUri(string $path, array $headers): string
177    {
178        $hostKey = array_filter(array_keys($headers), function ($k) {
179            // Numeric array keys are converted to int by PHP.
180            $k = (string) $k;
181
182            return strtolower($k) === 'host';
183        });
184
185        // If no host is found, then a full URI cannot be constructed.
186        if (!$hostKey) {
187            return $path;
188        }
189
190        $host = $headers[reset($hostKey)][0];
191        $scheme = substr($host, -4) === ':443' ? 'https' : 'http';
192
193        return $scheme.'://'.$host.'/'.ltrim($path, '/');
194    }
195
196    /**
197     * Parses a request message string into a request object.
198     *
199     * @param string $message Request message string.
200     */
201    public static function parseRequest(string $message): RequestInterface
202    {
203        $data = self::parseMessage($message);
204        $matches = [];
205        if (!preg_match('/^[\S]+\s+([a-zA-Z]+:\/\/|\/).*/', $data['start-line'], $matches)) {
206            throw new \InvalidArgumentException('Invalid request string');
207        }
208        $parts = explode(' ', $data['start-line'], 3);
209        $version = isset($parts[2]) ? explode('/', $parts[2])[1] : '1.1';
210
211        $request = new Request(
212            $parts[0],
213            $matches[1] === '/' ? self::parseRequestUri($parts[1], $data['headers']) : $parts[1],
214            $data['headers'],
215            $data['body'],
216            $version
217        );
218
219        return $matches[1] === '/' ? $request : $request->withRequestTarget($parts[1]);
220    }
221
222    /**
223     * Parses a response message string into a response object.
224     *
225     * @param string $message Response message string.
226     */
227    public static function parseResponse(string $message): ResponseInterface
228    {
229        $data = self::parseMessage($message);
230        // According to https://datatracker.ietf.org/doc/html/rfc7230#section-3.1.2
231        // the space between status-code and reason-phrase is required. But
232        // browsers accept responses without space and reason as well.
233        if (!preg_match('/^HTTP\/.* [0-9]{3}( .*|$)/', $data['start-line'])) {
234            throw new \InvalidArgumentException('Invalid response string: '.$data['start-line']);
235        }
236        $parts = explode(' ', $data['start-line'], 3);
237
238        return new Response(
239            (int) $parts[1],
240            $data['headers'],
241            $data['body'],
242            explode('/', $parts[0])[1],
243            $parts[2] ?? null
244        );
245    }
246}
247