<?php

/**

 * fsockopen HTTP transport

 *

 * @package Requests\Transport

 */

namespace WpOrg\Requests\Transport;

use WpOrg\Requests\Capability;

use WpOrg\Requests\Exception;

use WpOrg\Requests\Exception\InvalidArgument;

use WpOrg\Requests\Port;

use WpOrg\Requests\Requests;

use WpOrg\Requests\Ssl;

use WpOrg\Requests\Transport;

use WpOrg\Requests\Utility\CaseInsensitiveDictionary;

use WpOrg\Requests\Utility\InputValidator;

/**

 * fsockopen HTTP transport

 *

 * @package Requests\Transport

 */

final class Fsockopen implements Transport {

	/**

	 * Second to microsecond conversion

	 *

	 * @var integer

	 */

	const SECOND_IN_MICROSECONDS = 1000000;

	/**

	 * Raw HTTP data

	 *

	 * @var string

	 */

	public $headers = '';

	/**

	 * Stream metadata

	 *

	 * @var array Associative array of properties, see {@link https://www.php.net/stream_get_meta_data}

	 */

	public $info;

	/**

	 * What's the maximum number of bytes we should keep?

	 *

	 * @var int|bool Byte count, or false if no limit.

	 */

	private $max_bytes = false;

	/**

	 * Cache for received connection errors.

	 *

	 * @var string

	 */

	private $connect_error = '';

	/**

	 * Perform a request

	 *

	 * @param string|Stringable $url URL to request

	 * @param array $headers Associative array of request headers

	 * @param string|array $data Data to send either as the POST body, or as parameters in the URL for a GET/HEAD

	 * @param array $options Request options, see {@see \WpOrg\Requests\Requests::response()} for documentation

	 * @return string Raw HTTP result

	 *

	 * @throws \WpOrg\Requests\Exception\InvalidArgument When the passed $url argument is not a string or Stringable.

	 * @throws \WpOrg\Requests\Exception\InvalidArgument When the passed $headers argument is not an array.

	 * @throws \WpOrg\Requests\Exception\InvalidArgument When the passed $data parameter is not an array or string.

	 * @throws \WpOrg\Requests\Exception\InvalidArgument When the passed $options argument is not an array.

	 * @throws \WpOrg\Requests\Exception       On failure to connect to socket (`fsockopenerror`)

	 * @throws \WpOrg\Requests\Exception       On socket timeout (`timeout`)

	 */

	public function request($url, $headers = [], $data = [], $options = []) {

		if (InputValidator::is_string_or_stringable($url) === false) {

			throw InvalidArgument::create(1, '$url', 'string|Stringable', gettype($url));

		}

		if (is_array($headers) === false) {

			throw InvalidArgument::create(2, '$headers', 'array', gettype($headers));

		}

		if (!is_array($data) && !is_string($data)) {

			if ($data === null) {

				$data = '';

			} else {

				throw InvalidArgument::create(3, '$data', 'array|string', gettype($data));

			}

		}

		if (is_array($options) === false) {

			throw InvalidArgument::create(4, '$options', 'array', gettype($options));

		}

		$options['hooks']->dispatch('fsockopen.before_request');

		$url_parts = parse_url($url);

		if (empty($url_parts)) {

			throw new Exception('Invalid URL.', 'invalidurl', $url);

		}

		$host                     = $url_parts['host'];

		$context                  = stream_context_create();

		$verifyname               = false;

		$case_insensitive_headers = new CaseInsensitiveDictionary($headers);

		// HTTPS support

		if (isset($url_parts['scheme']) && strtolower($url_parts['scheme']) === 'https') {

			$remote_socket = 'ssl://' . $host;

			if (!isset($url_parts['port'])) {

				$url_parts['port'] = Port::HTTPS;

			}

			$context_options = [

				'verify_peer'       => true,

				'capture_peer_cert' => true,

			];

			$verifyname      = true;

			// SNI, if enabled (OpenSSL >=0.9.8j)

			// phpcs:ignore PHPCompatibility.Constants.NewConstants.openssl_tlsext_server_nameFound

			if (defined('OPENSSL_TLSEXT_SERVER_NAME') && OPENSSL_TLSEXT_SERVER_NAME) {

				$context_options['SNI_enabled'] = true;

				if (isset($options['verifyname']) && $options['verifyname'] === false) {

					$context_options['SNI_enabled'] = false;

				}

			}

			if (isset($options['verify'])) {

				if ($options['verify'] === false) {

					$context_options['verify_peer']      = false;

					$context_options['verify_peer_name'] = false;

					$verifyname                          = false;

				} elseif (is_string($options['verify'])) {

					$context_options['cafile'] = $options['verify'];

				}

			}

			if (isset($options['verifyname']) && $options['verifyname'] === false) {

				$context_options['verify_peer_name'] = false;

				$verifyname                          = false;

			}

			// Handle the PHP 8.4 deprecation (PHP 9.0 removal) of the function signature we use for stream_context_set_option().

			// Ref: https://wiki.php.net/rfc/deprecate_functions_with_overloaded_signatures#stream_context_set_option

			if (function_exists('stream_context_set_options')) {

				// PHP 8.3+.

				stream_context_set_options($context, ['ssl' => $context_options]);

			} else {

				// PHP < 8.3.

				stream_context_set_option($context, ['ssl' => $context_options]);

			}

		} else {

			$remote_socket = 'tcp://' . $host;

		}

		$this->max_bytes = $options['max_bytes'];

		if (!isset($url_parts['port'])) {

			$url_parts['port'] = Port::HTTP;

		}

		$remote_socket .= ':' . $url_parts['port'];

		// phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_set_error_handler

		set_error_handler([$this, 'connect_error_handler'], E_WARNING | E_NOTICE);

		$options['hooks']->dispatch('fsockopen.remote_socket', [&$remote_socket]);

		$socket = stream_socket_client($remote_socket, $errno, $errstr, ceil($options['connect_timeout']), STREAM_CLIENT_CONNECT, $context);

		restore_error_handler();

		if ($verifyname && !$this->verify_certificate_from_context($host, $context)) {

			throw new Exception('SSL certificate did not match the requested domain name', 'ssl.no_match');

		}

		if (!$socket) {

			if ($errno === 0) {

				// Connection issue

				throw new Exception(rtrim($this->connect_error), 'fsockopen.connect_error');

			}

			throw new Exception($errstr, 'fsockopenerror', null, $errno);

		}

		$data_format = $options['data_format'];

		if ($data_format === 'query') {

			$path = self::format_get($url_parts, $data);

			$data = '';

		} else {

			$path = self::format_get($url_parts, []);

		}

		$options['hooks']->dispatch('fsockopen.remote_host_path', [&$path, $url]);

		$request_body = '';

		$out          = sprintf("%s %s HTTP/%.1F\r\n", $options['type'], $path, $options['protocol_version']);

		if ($options['type'] !== Requests::TRACE) {

			if (is_array($data)) {

				$request_body = http_build_query($data, '', '&');

			} else {

				$request_body = $data;

			}

			// Always include Content-length on POST requests to prevent

			// 411 errors from some servers when the body is empty.

			if (!empty($data) || $options['type'] === Requests::POST) {

				if (!isset($case_insensitive_headers['Content-Length'])) {

					$headers['Content-Length'] = strlen($request_body);

				}

				if (!isset($case_insensitive_headers['Content-Type'])) {

					$headers['Content-Type'] = 'application/x-www-form-urlencoded; charset=UTF-8';

				}

			}

		}

		if (!isset($case_insensitive_headers['Host'])) {

			$out         .= sprintf('Host: %s', $url_parts['host']);

			$scheme_lower = strtolower($url_parts['scheme']);

			if (($scheme_lower === 'http' && $url_parts['port'] !== Port::HTTP) || ($scheme_lower === 'https' && $url_parts['port'] !== Port::HTTPS)) {

				$out .= ':' . $url_parts['port'];

			}

			$out .= "\r\n";

		}

		if (!isset($case_insensitive_headers['User-Agent'])) {

			$out .= sprintf("User-Agent: %s\r\n", $options['useragent']);

		}

		$accept_encoding = $this->accept_encoding();

		if (!isset($case_insensitive_headers['Accept-Encoding']) && !empty($accept_encoding)) {

			$out .= sprintf("Accept-Encoding: %s\r\n", $accept_encoding);

		}

		$headers = Requests::flatten($headers);

		if (!empty($headers)) {

			$out .= implode("\r\n", $headers) . "\r\n";

		}

		$options['hooks']->dispatch('fsockopen.after_headers', [&$out]);

		if (substr($out, -2) !== "\r\n") {

			$out .= "\r\n";

		}

		if (!isset($case_insensitive_headers['Connection'])) {

			$out .= "Connection: Close\r\n";

		}

		$out .= "\r\n" . $request_body;

		$options['hooks']->dispatch('fsockopen.before_send', [&$out]);

		fwrite($socket, $out);

		$options['hooks']->dispatch('fsockopen.after_send', [$out]);

		if (!$options['blocking']) {

			fclose($socket);

			$fake_headers = '';

			$options['hooks']->dispatch('fsockopen.after_request', [&$fake_headers]);

			return '';

		}

		$timeout_sec = (int) floor($options['timeout']);

		if ($timeout_sec === $options['timeout']) {

			$timeout_msec = 0;

		} else {

			$timeout_msec = self::SECOND_IN_MICROSECONDS * $options['timeout'] % self::SECOND_IN_MICROSECONDS;

		}

		stream_set_timeout($socket, $timeout_sec, $timeout_msec);

		$response   = '';

		$body       = '';

		$headers    = '';

		$this->info = stream_get_meta_data($socket);

		$size       = 0;

		$doingbody  = false;

		$download   = false;

		if ($options['filename']) {

			// phpcs:ignore WordPress.PHP.NoSilencedErrors -- Silenced the PHP native warning in favour of throwing an exception.

			$download = @fopen($options['filename'], 'wb');

			if ($download === false) {

				$error = error_get_last();

				throw new Exception($error['message'], 'fopen');

			}

		}

		while (!feof($socket)) {

			$this->info = stream_get_meta_data($socket);

			if ($this->info['timed_out']) {

				throw new Exception('fsocket timed out', 'timeout');

			}

			$block = fread($socket, Requests::BUFFER_SIZE);

			if (!$doingbody) {

				$response .= $block;

				if (strpos($response, "\r\n\r\n")) {

					list($headers, $block) = explode("\r\n\r\n", $response, 2);

					$doingbody             = true;

				}

			}

			// Are we in body mode now?

			if ($doingbody) {

				$options['hooks']->dispatch('request.progress', [$block, $size, $this->max_bytes]);

				$data_length = strlen($block);

				if ($this->max_bytes) {

					// Have we already hit a limit?

					if ($size === $this->max_bytes) {

						continue;

					}

					if (($size + $data_length) > $this->max_bytes) {

						// Limit the length

						$limited_length = ($this->max_bytes - $size);

						$block          = substr($block, 0, $limited_length);

					}

				}

				$size += strlen($block);

				if ($download) {

					fwrite($download, $block);

				} else {

					$body .= $block;

				}

			}

		}

		$this->headers = $headers;

		if ($download) {

			fclose($download);

		} else {

			$this->headers .= "\r\n\r\n" . $body;

		}

		fclose($socket);

		$options['hooks']->dispatch('fsockopen.after_request', [&$this->headers, &$this->info]);

		return $this->headers;

	}

	/**

	 * Send multiple requests simultaneously

	 *

	 * @param array $requests Request data (array of 'url', 'headers', 'data', 'options') as per {@see \WpOrg\Requests\Transport::request()}

	 * @param array $options Global options, see {@see \WpOrg\Requests\Requests::response()} for documentation

	 * @return array Array of \WpOrg\Requests\Response objects (may contain \WpOrg\Requests\Exception or string responses as well)

	 *

	 * @throws \WpOrg\Requests\Exception\InvalidArgument When the passed $requests argument is not an array or iterable object with array access.

	 * @throws \WpOrg\Requests\Exception\InvalidArgument When the passed $options argument is not an array.

	 */

	public function request_multiple($requests, $options) {

		// If you're not requesting, we can't get any responses ¯\_(ツ)_/¯

		if (empty($requests)) {

			return [];

		}

		if (InputValidator::has_array_access($requests) === false || InputValidator::is_iterable($requests) === false) {

			throw InvalidArgument::create(1, '$requests', 'array|ArrayAccess&Traversable', gettype($requests));

		}

		if (is_array($options) === false) {

			throw InvalidArgument::create(2, '$options', 'array', gettype($options));

		}

		$responses = [];

		$class     = get_class($this);

		foreach ($requests as $id => $request) {

			try {

				$handler        = new $class();

				$responses[$id] = $handler->request($request['url'], $request['headers'], $request['data'], $request['options']);

				$request['options']['hooks']->dispatch('transport.internal.parse_response', [&$responses[$id], $request]);

			} catch (Exception $e) {

				$responses[$id] = $e;

			}

			if (!is_string($responses[$id])) {

				$request['options']['hooks']->dispatch('multiple.request.complete', [&$responses[$id], $id]);

			}

		}

		return $responses;

	}

	/**

	 * Retrieve the encodings we can accept

	 *

	 * @return string Accept-Encoding header value

	 */

	private static function accept_encoding() {

		$type = [];

		if (function_exists('gzinflate')) {

			$type[] = 'deflate;q=1.0';

		}

		if (function_exists('gzuncompress')) {

			$type[] = 'compress;q=0.5';