<?php
/**
 * Copyright (c) 2007-2011, Servigistics, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  - Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *  - Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *  - Neither the name of Servigistics, Inc. nor the names of
 *    its contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 * @copyright Copyright 2007-2011 Servigistics, Inc. (http://servigistics.com)
 * @license http://solr-php-client.googlecode.com/svn/trunk/COPYING New BSD
 *
 * @version $Id: $
 *
 * @author Donovan Jimenez <djimenez@conduit-it.com>
 */

/**
 * HTTP Transport implemenation that uses the builtin http URL wrappers and file_get_contents.
 */
class Apache_Solr_HttpTransport_FileGetContents extends Apache_Solr_HttpTransport_Abstract
{
    /**
     * SVN Revision meta data for this class.
     */
    const SVN_REVISION = '$Revision:  $';

    /**
     * SVN ID meta data for this class.
     */
    const SVN_ID = '$Id:  $';

    /**
     * Reusable stream context resources for GET and POST operations.
     *
     * @var resource
     */
    private $_getContext;
    private $_headContext;
    private $_postContext;

    /**
     * For POST operations, we're already using the Header context value for
     * specifying the content type too, so we have to keep our computed
     * authorization header around.
     *
     * @var string
     */
    private $_authHeader = '';

    /**
     * Initializes our reuseable get and post stream contexts.
     */
    public function __construct()
    {
        $this->_getContext = stream_context_create();
        $this->_headContext = stream_context_create();
        $this->_postContext = stream_context_create();
    }

    public function setAuthenticationCredentials($username, $password)
    {
        // compute the Authorization header
        $this->_authHeader = 'Authorization: Basic '.base64_encode($username.':'.$password);

        // set it now for get and head contexts
        stream_context_set_option($this->_getContext, 'http', 'header', $this->_authHeader);
        stream_context_set_option($this->_headContext, 'http', 'header', $this->_authHeader);

        // for post, it'll be set each time, so add an \r\n so it can be concatenated
        // with the Content-Type
        $this->_authHeader .= "\r\n";
    }

    public function performGetRequest($url, $timeout = false)
    {
        // set the timeout if specified
        if (false !== $timeout && $timeout > 0.0) {
            // timeouts with file_get_contents seem to need
            // to be halved to work as expected
            $timeout = (float) $timeout / 2;

            stream_context_set_option($this->_getContext, 'http', 'timeout', $timeout);
        } else {
            // use the default timeout pulled from default_socket_timeout otherwise
            stream_context_set_option($this->_getContext, 'http', 'timeout', $this->getDefaultTimeout());
        }

        // $http_response_headers will be updated by the call to file_get_contents later
        // see http://us.php.net/manual/en/wrappers.http.php for documentation
        // Unfortunately, it will still create a notice in analyzers if we don't set it here
        $http_response_header = null;
        $responseBody = @file_get_contents($url, false, $this->_getContext);

        return $this->_getResponseFromParts($responseBody, $http_response_header);
    }

    public function performHeadRequest($url, $timeout = false)
    {
        stream_context_set_option($this->_headContext, [
                'http' => [
                    // set HTTP method
                    'method' => 'HEAD',

                    // default timeout
                    'timeout' => $this->getDefaultTimeout(),
                ],
            ]
        );

        // set the timeout if specified
        if (false !== $timeout && $timeout > 0.0) {
            // timeouts with file_get_contents seem to need
            // to be halved to work as expected
            $timeout = (float) $timeout / 2;

            stream_context_set_option($this->_headContext, 'http', 'timeout', $timeout);
        }

        // $http_response_headers will be updated by the call to file_get_contents later
        // see http://us.php.net/manual/en/wrappers.http.php for documentation
        // Unfortunately, it will still create a notice in analyzers if we don't set it here
        $http_response_header = null;
        $responseBody = @file_get_contents($url, false, $this->_headContext);

        return $this->_getResponseFromParts($responseBody, $http_response_header);
    }

    public function performPostRequest($url, $rawPost, $contentType, $timeout = false)
    {
        stream_context_set_option($this->_postContext, [
                'http' => [
                    // set HTTP method
                    'method' => 'POST',

                    // Add our posted content type (and auth header - see setAuthentication)
                    'header' => "{$this->_authHeader}Content-Type: {$contentType}",

                    // the posted content
                    'content' => $rawPost,

                    // default timeout
                    'timeout' => $this->getDefaultTimeout(),
                ],
            ]
        );

        // set the timeout if specified
        if (false !== $timeout && $timeout > 0.0) {
            // timeouts with file_get_contents seem to need
            // to be halved to work as expected
            $timeout = (float) $timeout / 2;

            stream_context_set_option($this->_postContext, 'http', 'timeout', $timeout);
        }

        // $http_response_header will be updated by the call to file_get_contents later
        // see http://us.php.net/manual/en/wrappers.http.php for documentation
        // Unfortunately, it will still create a notice in analyzers if we don't set it here
        $http_response_header = null;
        $responseBody = @file_get_contents($url, false, $this->_postContext);

        // reset content of post context to reclaim memory
        stream_context_set_option($this->_postContext, 'http', 'content', '');

        return $this->_getResponseFromParts($responseBody, $http_response_header);
    }

    private function _getResponseFromParts($rawResponse, $httpHeaders)
    {
        //Assume 0, false as defaults
        $status = 0;
        $contentType = false;

        //iterate through headers for real status, type, and encoding
        if (is_array($httpHeaders) && count($httpHeaders) > 0) {
            //look at the first headers for the HTTP status code
            //and message (errors are usually returned this way)
            //
            //HTTP 100 Continue response can also be returned before
            //the REAL status header, so we need look until we find
            //the last header starting with HTTP
            //
            //the spec: http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.1
            //
            //Thanks to Daniel Andersson for pointing out this oversight
            while (isset($httpHeaders[0]) && 'HTTP' == substr($httpHeaders[0], 0, 4)) {
                // we can do a intval on status line without the "HTTP/1.X " to get the code
                $status = intval(substr($httpHeaders[0], 9));

                // remove this from the headers so we can check for more
                array_shift($httpHeaders);
            }

            //Look for the Content-Type response header and determine type
            //and encoding from it (if possible - such as 'Content-Type: text/plain; charset=UTF-8')
            foreach ($httpHeaders as $header) {
                // look for the header that starts appropriately
                if (0 == strncasecmp($header, 'Content-Type:', 13)) {
                    $contentType = substr($header, 13);
                    break;
                }
            }
        }

        return new Apache_Solr_HttpTransport_Response($status, $contentType, $rawResponse);
    }
}
