<?php
if( !defined( '_JEXEC' ) ) die( 'Direct Access to '.basename(__FILE__).' is not allowed.' );
/**
 *
 * @version $Id:connection.php 431 2006-10-17 21:55:46 +0200 (Di, 17 Okt 2006) soeren_nb $
 * @package VirtueMart
 * @subpackage classes
 * @copyright Copyright (C) 2004-2007 soeren, 2009-2011 VirtueMart Team. All rights reserved.
 * @license http://www.gnu.org/copyleft/gpl.html GNU/GPL, see LICENSE.php
 * VirtueMart is free software. This version may have been modified pursuant
 * to the GNU General Public License, and as distributed it includes or
 * is derivative of works licensed under the GNU General Public License or
 * other free or open source software licenses.
 * See /administrator/components/com_virtuemart/COPYRIGHT.php for copyright notices and details.
 *
 * http://virtuemart.org
 */

/**
 * Provides general tools to handle connections (http, headers, ... )
 *
 * @author soeren
 * @since VirtueMart 1.1.0
 */
class VmConnector {

    var $handle = null;

    /**
     * Clears the output buffer, sends a http status code and a content if given
     * @static
     * @param int $http_status
     * @param string $mime_type
     * @param string $content
     */
    function sendHeaderAndContent( $http_status=200, $content='', $mime_type='text/html' ) {

	// Clear all Joomla header and buffer stuff
	while( @ob_end_clean() );

	$http_status = intval( $http_status );
	@header("HTTP/1.0 $http_status");
	if( $mime_type ) {
	    @header( "Content-type: $mime_type; charset=UTF-8" );
	} elseif( $mime_type != '' ) {
	    @header( "Content-type: text/html; charset=UTF-8" );
	}
	if( $content ) {
	    echo $content;
	}
    }
    /**
     * This is a general function to safely open a connection to a server,
     * post data when needed and read the result.
     * Tries using cURL and switches to fopen/fsockopen if cURL is not available
     * @since VirtueMart 1.1.0
     * @static
     * @param string $url
     * @param string $postData
     * @param array $headers
     * @param resource $fileToSaveData
     * @return mixed
     */
    static function handleCommunication( $url, $postData='', $headers=array(), $fileToSaveData=null ) {

	$urlParts = parse_url( $url );
	if( !isset( $urlParts['port'] )) $urlParts['port'] = 80;
	if( !isset( $urlParts['scheme'] )) $urlParts['scheme'] = 'http';

	if( isset( $urlParts['query'] )){
		 $urlParts['query'] = '?'.$urlParts['query'];
		if( isset( $urlParts['path'] )) $urlParts['path'] = $urlParts['path'].$urlParts['query'];
	}

	$vm_proxy_url = VmConfig::get('conf_VM_PROXY_URL','');
	// Check proxy
	if( trim( $vm_proxy_url ) != '') {
	    if( !stristr($vm_proxy_url, 'http')) {
		$proxyURL['host'] = $vm_proxy_url;
		$proxyURL['scheme'] = 'http';
	    } else {
		$proxyURL = parse_url($vm_proxy_url);
	    }
	}
	else {
	    $proxyURL = '';
	}

	if( function_exists( "curl_init" ) && function_exists( 'curl_exec' ) ) {
	    $CR = curl_init();
	    curl_setopt($CR, CURLOPT_URL, $url);

	    // just to get sure the script doesn't die
	    curl_setopt($CR, CURLOPT_TIMEOUT, 30 );
	    if( !empty( $headers )) {
		// Add additional headers if provided
		curl_setopt($CR, CURLOPT_HTTPHEADER, $headers);
	    }
	    curl_setopt($CR, CURLOPT_FAILONERROR, true);
	    if( $postData ) {
		curl_setopt($CR, CURLOPT_POSTFIELDS, $postData );
		curl_setopt($CR, CURLOPT_POST, 1);
	    }
	    if( is_resource($fileToSaveData)) {
		curl_setopt($CR, CURLOPT_FILE, $fileToSaveData );
	    } else {
		curl_setopt($CR, CURLOPT_RETURNTRANSFER, 1);
	    }
	    // Do we need to set up the proxy?
	    if( !empty($proxyURL) ) {
//		$vmLogger->debug( 'Setting up proxy: '.$proxyURL['host'].':'.VM_PROXY_PORT );
		//curl_setopt($CR, CURLOPT_HTTPPROXYTUNNEL, true);
		curl_setopt($CR, CURLOPT_PROXY, $proxyURL['host'] );
		curl_setopt($CR, CURLOPT_PROXYPORT, VM_PROXY_PORT );
		// Check if the proxy needs authentication
		if( trim( @VM_PROXY_USER ) != '') {
//		    $vmLogger->debug( 'Using proxy authentication!' );
		    curl_setopt($CR, CURLOPT_PROXYUSERPWD, VM_PROXY_USER.':'.VM_PROXY_PASS );
		}
	    }

	    if( $urlParts['scheme'] == 'https') {
		// No PEER certificate validation...as we don't have
		// a certificate file for it to authenticate the host www.ups.com against!
		curl_setopt($CR, CURLOPT_SSL_VERIFYPEER, 0);

	    }
	    $result = curl_exec( $CR );
	    $error = curl_error( $CR );
	    if( !empty( $error ) && stristr( $error, '502') && !empty( $proxyURL )) {
//		$vmLogger->debug( 'Switching to NTLM authenticaton.');
		curl_setopt( $CR, CURLOPT_PROXYAUTH, CURLAUTH_NTLM );
		$result = curl_exec( $CR );
		$error = curl_error( $CR );
	    }
	    curl_close( $CR );

	    if( !empty( $error )) {

			return false;
	    } else {
			return $result;
	    }
	} else {
	    if( $postData ) {
			if( !empty( $proxyURL )) {
			    // If we have something to post we need to write into a socket
			    if( $proxyURL['scheme'] == 'https') {
				$protocol = 'ssl';
			    }
			    else {
				$protocol = 'http';
			    }
			    $fp = fsockopen("$protocol://".$proxyURL['host'], VM_PROXY_PORT, $errno, $errstr, $timeout = 30);
			}
			else {
			    // If we have something to post we need to write into a socket
			    if( $urlParts['scheme'] == 'https') {
				$protocol = 'ssl';
			    }
			    else {
				$protocol = $urlParts['scheme'];
			    }
			    $fp = fsockopen("$protocol://".$urlParts['host'], $urlParts['port'], $errno, $errstr, $timeout = 30);
			}
	    } else {
			if( !empty( $proxyURL )) {
			    // Do a read-only fopen transaction
			    $fp = fopen( $proxyURL['scheme'].'://'.$proxyURL['host'].':'.VM_PROXY_PORT, 'rb' );
			}
			else {
			    // Do a read-only fopen transaction
			    $fp = fopen( $urlParts['scheme'].'://'.$urlParts['host'].':'.$urlParts['port'].$urlParts['path'], 'rb' );
			}
	    }
	    if(!$fp) {
			//error tell us
			vmWarn( 'Possible server error! - '.$errstr .'('.$errno.')\n' );
			return false;
	    }
	    else {
	    	vmdebug( 'Connection opened to '.$urlParts['host']);
	    }
	    if( $postData ) {
			//send the server request
			if( !empty( $proxyURL )) {
			    fputs($fp, "POST ".$urlParts['host'].':'.$urlParts['port'].$urlParts['path']." HTTP/1.0\r\n");
			    fputs($fp, "Host: ".$proxyURL['host']."\r\n");

			    if( trim( @VM_PROXY_USER )!= '') {
				fputs($fp, "Proxy-Authorization: Basic " . base64_encode (VM_PROXY_USER.':'.VM_PROXY_PASS ) . "\r\n\r\n");
			    }
			}
			else {
			    fputs($fp, 'POST '.$urlParts['path']." HTTP/1.0\r\n");
			    fputs($fp, 'Host:'. $urlParts['host']."\r\n");
			}
			fputs($fp, "Content-type: application/x-www-form-urlencoded\r\n");
			fputs($fp, "Content-length: ".strlen($postData)."\r\n");
			fputs($fp, "Connection: close\r\n\r\n");
			fputs($fp, $postData . "\r\n\r\n");
	    } else {
			if( !empty( $proxyURL )) {
			    fputs($fp, "GET ".$urlParts['host'].':'.$urlParts['port'].$urlParts['path']." HTTP/1.0\r\n");
			    fputs($fp, "Host: ".$proxyURL['host']."\r\n");
			    if( trim( @VM_PROXY_USER )!= '') {
				fputs($fp, "Proxy-Authorization: Basic " . base64_encode (VM_PROXY_USER.':'.VM_PROXY_PASS ) . "\r\n\r\n");
			    }
			}
			else {
			    fputs($fp, 'GET '.$urlParts['path']." HTTP/1.0\r\n");
			    fputs($fp, 'Host:'. $urlParts['host']."\r\n");
			}
	    }
	    // Add additional headers if provided
	    foreach( $headers as $header ) {
			fputs($fp, $header."\r\n");
	    }
	    $data = "";
	    while (!feof($fp)) {
			$data .= @fgets ($fp, 4096);
	    }
	    fclose( $fp );

	    // If didnt get content-length, something is wrong, return false.
	    if ( trim($data) == '' ) {
			vmWarn('An error occured while communicating with the server '.$urlParts['host'].'. It didn\'t reply (correctly). Please try again later, thank you.' );
			return false;
	    }
	    $result = trim( $data );
	    if( is_resource($fileToSaveData )) {
			fwrite($fileToSaveData, $result );
			return true;
	    } else {
			return $result;
	    }
	}
    }
    /**
     * Set headers and send the file to the client
     *
     * @author Andreas Gohr <andi@splitbrain.org>
     * @param string The full path to the file
     * @param string The Mime Type of the file
     */
    function sendFile($file,$mime, $overrideFileName='') {

	// send headers
	header("Content-Type: $mime");

	list($start,$len) = VmConnector::http_rangeRequest(filesize($file));

	header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
	header('Pragma: public');
	header('Accept-Ranges: bytes');

	//application mime type is downloadable
	if(strtolower(substr($mime,0,11)) == 'application') {
	    if( $overrideFileName == '') {
		$filename = basename($file);
	    } else {
		$filename = $overrideFileName;
	    }
	    header('Content-Disposition: attachment; filename="'.$filename.'";');
	}

	$chunksize = 1*(1024*1024);
	// send file contents
	$fp = @fopen($file,"rb");
	if($fp) {
	    fseek($fp,$start); //seek to start of range

	    $chunk = ($len > $chunksize) ? $chunksize : $len;
	    while (!feof($fp) && $chunk > 0) {
		@set_time_limit(); // large files can take a lot of time
		print fread($fp, $chunk);
		flush();
		$len -= $chunk;
		$chunk = ($len > $chunksize) ? $chunksize : $len;
	    }
	    fclose($fp);
	}else {
	    header("HTTP/1.0 500 Internal Server Error");
	    print "Could not read $file - bad permissions?";
	    JFactory::getApplication()->close(true);
	}
    }
    /**
     * Checks and sets headers to handle range requets
     *
     * @author  Andreas Gohr <andi@splitbrain.org>
     * @return array The start byte and the amount of bytes to send
     * @param int The file size
     */
    function http_rangeRequest($size, $exitOnError=true ) {

	if(!isset($_SERVER['HTTP_RANGE'])) {
	    // no range requested - send the whole file
	    header("Content-Length: $size");
	    return array(0,$size);
	}

	$t = explode('=', $_SERVER['HTTP_RANGE']);
	if (!$t[0]=='bytes') {
	    // we only understand byte ranges - send the whole file
	    header("Content-Length: $size");
	    return array(0,$size);
	}

	$r = explode('-', $t[1]);
	$start = (int)$r[0];
	$end = (int)$r[1];
	if (!$end) $end = $size - 1;
	if ($start > $end || $start > $size || $end > $size) {
	    if( $exitOnError ) {
		header('HTTP/1.1 416 Requested Range Not Satisfiable');
		print 'Bad Range Request!';
		JFactory::getApplication()->close(true);
	    } else {
		return array(0,$size);
	    }
	}

	$tot = $end - $start + 1;
	header('HTTP/1.1 206 Partial Content');
	header("Content-Range: bytes {$start}-{$end}/{$size}");
	header("Content-Length: $tot");

	return array($start,$tot);
    }
}
// pure php no closing tag