<?php
# -- BEGIN LICENSE BLOCK ---------------------------------------
#
# This file is part of Clearbricks.
#
# Copyright (c) 2003-2010 Olivier Meunier & Association Dotclear
# Licensed under the GPL version 2.0 license.
# See LICENSE file or
# http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
#
# -- END LICENSE BLOCK -----------------------------------------

/**
* HTTP Client
*
* Features:
*
* - Implements a useful subset of the HTTP 1.0 and 1.1 protocols.
* - Includes cookie support.
* - Ability to set the user agent and referal fields.
* - Can automatically handle redirected pages.
* - Can be used for multiple requests, with any cookies sent by the server resent
*   for each additional request.
* - Support for gzip encoded content, which can dramatically reduce the amount of
*   bandwidth used in a transaction.
* - Object oriented, with static methods providing a useful shortcut for simple
*   requests.
* - The ability to only read the page headers - useful for implementing tools such
*   as link checkers.
* - Support for file uploads.
*
* This class is fully based on Simon Willison's HTTP Client in version 0.9 of
* 6th April 2003 - {@link http://scripts.incutio.com/httpclient/}
*
* Changes since fork:
*
* - PHP5 only with Exception support
* - Charset support in POST requests
* - Proxy support through HTTP_PROXY_HOST and HTTP_PROXY_PORT or setProxy()
* - SSL support (if possible)
* - Handles redirects on other hosts
* - Configurable output
*
* @package Clearbricks
* @subpackage Network
*/
if (class_exists('netSocket'))
{
	class netHttp extends netSocket
	{
		/** @var string Server host */				protected $host;
		/** @var integer Server port */				protected $port;
		/** @var string Query path */					protected $path;
		/** @var string HTTP method */				protected $method;
		/** @var string POST query string */			protected $postdata = '';
		/** @var string POST charset */				protected $post_charset;
		/** @var array Cookies sent */				protected $cookies = array();
		/** @var string HTTP referer */				protected $referer;
		/** @var string HTTP accept header */			protected $accept = 'text/xml,application/xml,application/xhtml+xml,text/html,text/plain,image/png,image/jpeg,image/gif,*/*';
		/** @var string HTTP accept encoding */			protected $accept_encoding = 'gzip';
		/** @var string HTTP accept language */			protected $accept_language = 'en-us';
		/** @var string HTTP User Agent */				protected $user_agent = 'Clearbricks HTTP Client';
		/** @var array More headers to be sent */		protected $more_headers = array();
		/** @var integer Connection timeout */			protected $timeout = 10;
		/** @var boolean Use SSL connection */			protected $use_ssl = false;
		/** @var boolean Use gzip transfert */			protected $use_gzip = false;
		/** @var boolean Allow persistant cookies */		protected $persist_cookies = true;
		/** @var boolean Allow persistant referers */	protected $persist_referers = true;
		/** @var boolean Use debug mode */				protected $debug = false;
		/** @var boolean Follow redirects */			protected $handle_redirects = true;
		/** @var integer Maximum redirects to follow */	protected $max_redirects = 5;
		/** @var boolean Retrieve only headers */		protected $headers_only = false;
		/** @var string Authentication user name */		protected $username;
		/** @var string Authentication password */		protected $password;
		/** @var string Proxy server host */			protected $proxy_host;
		/** @var integer Proxy server port */			protected $proxy_port;
		
		# Response vars
		/** @var integer HTTP Status code */			protected $status;
		/** @var string HTTP Status string */			protected $status_string;
		/** @var array Response headers */				protected $headers = array();
		/** @var string Response body */				protected $content = '';
		
		# Tracker variables
		/** @var integer Internal redirects count */		protected $redirect_count = 0;
		/** @var string Internal cookie host */			protected $cookie_host = '';
		
		# Output module (null is this->content)
		/** @var string Output stream name */			protected $output = null;
		/** @var resource Output resource */			protected $output_h = null;
		
		
		/**
		* Constructor.
		*
		* Takes the web server host, an optional port and timeout.
		*
		* @param string	$host			Server host
		* @param integer	$port			Server port
		* @param integer	$timeout			Connection timeout
		*/
		public function __construct($host,$port=80,$timeout=null)
		{
			$this->setHost($host,$port);
			
			if (defined('HTTP_PROXY_HOST') && defined('HTTP_PROXY_PORT')) {
				$this->setProxy(HTTP_PROXY_HOST,HTTP_PROXY_PORT);
			}
			
			if ($timeout) {
				$this->setTimeout($timeout);
			}
			$this->_timeout =& $this->timeout;
		}
		
		/**
		* GET Request
		*
		* Executes a GET request for the specified path. If <var>$data</var> is
		* specified, appends it to a query string as part of the get request.
		* <var>$data</var> can be an array of key value pairs, in which case a
		* matching query string will be constructed. Returns true on success.
		* 
		* @param string	$path			Request path
		* @param array		$data			Request parameters
		* @return boolean
		*/
		public function get($path,$data=false)
		{
			$this->path = $path;
			$this->method = 'GET';
			
			if ($data) {
				$this->path .= '?'.$this->buildQueryString($data);
			}
			
			return $this->doRequest();
		}
		
		/**
		* POST Request
		*
		* Executes a POST request for the specified path. If <var>$data</var> is
		* specified, appends it to a query string as part of the get request.
		* <var>$data</var> can be an array of key value pairs, in which case a
		* matching query string will be constructed. Returns true on success.
		*
		* @param string	$path			Request path
		* @param array		$data			Request parameters
		* @param array		$charset			Request charset
		* @return boolean
		*/
		public function post($path,$data,$charset=null)
		{
			if ($charset) {
				$this->post_charset = $charset;
			}
			$this->path = $path;
			$this->method = 'POST';
			$this->postdata = $this->buildQueryString($data);
			return $this->doRequest();
		}
		
		/**
		* Query String Builder
		*
		* Prepares Query String for HTTP request. <var>$data</var> is an associative
		* array of arguments.
		*
		* @param array		$data			Query data
		* @return string
		*/
		protected function buildQueryString($data)
		{
			if (is_array($data))
			{
				$qs = array();
				# Change data in to postable data
				foreach ($data as $key => $val)
				{
					if (is_array($val)) {
						foreach ($val as $val2) {
							$qs[] = urlencode($key).'='.urlencode($val2);
						}
					} else {
						$qs[] = urlencode($key).'='.urlencode($val);
					}
				}
				$qs = implode('&',$qs);
			} else {
				$qs = $data;
			}
			
			return $qs;
		}
		
		/**
		* Do Request
		*
		* Sends HTTP request and stores status, headers, content object properties.
		*
		* @return boolean
		*/
		protected function doRequest()
		{
			if ($this->proxy_host && $this->proxy_port) {
				if ($this->use_ssl) {
					throw new Exception('SSL support is not available through a proxy');
				}
				$this->_host = $this->proxy_host;
				$this->_port = $this->proxy_port;
				$this->_transport = '';
			} else {
				$this->_host = $this->host;
				$this->_port = $this->port;
				$this->_transport = $this->use_ssl ? 'ssl://' : '';
			}
			
			#Reset all the variables that should not persist between requests
			$this->headers = array();
			$in_headers = true;
			$this->outputOpen();
			
			$request = $this->buildRequest();
			$this->debug('Request',implode("\r",$request));
			
			$this->open();
			$this->debug('Connecting to '.$this->_transport.$this->_host.':'.$this->_port);
			foreach($this->write($request) as $index => $line)
			{
				# Deal with first line of returned data
				if ($index == 0)
				{
					$line = rtrim($line,"\r\n");
					if (!preg_match('/HTTP\/(\\d\\.\\d)\\s*(\\d+)\\s*(.*)/', $line, $m)) {
						throw new Exception('Status code line invalid: '.$line);
					}
					$http_version = $m[1]; # not used
					$this->status = $m[2];
					$this->status_string = $m[3]; # not used
					$this->debug($line);
					continue;
				}
				
				# Read headers
				if ($in_headers)
				{
					$line = rtrim($line,"\r\n");
					if ($line == '')
					{
						$in_headers = false;
						$this->debug('Received Headers',$this->headers);
						if ($this->headers_only) {
							break;
						}
						continue;
					}
					
					if (!preg_match('/([^:]+):\\s*(.*)/', $line, $m)) {
						# Skip to the next header
						continue;
					}
					$key = strtolower(trim($m[1]));
					$val = trim($m[2]);
					# Deal with the possibility of multiple headers of same name
					if (isset($this->headers[$key])) {
						if (is_array($this->headers[$key])) {
							$this->headers[$key][] = $val;
						} else {
							$this->headers[$key] = array($this->headers[$key], $val);
						}
					} else {
						$this->headers[$key] = $val;
					}
					continue;
				}
				
				# We're not in the headers, so append the line to the contents
				$this->outputWrite($line);
			}
			$this->close();
			$this->outputClose();
			
			# If data is compressed, uncompress it
			if ($this->getHeader('content-encoding') && $this->use_gzip) {
				$this->debug('Content is gzip encoded, unzipping it');
				# See http://www.php.net/manual/en/function.gzencode.php
				$this->content = gzinflate(substr($this->content, 10));
			}
			
			# If $persist_cookies, deal with any cookies
			if ($this->persist_cookies && $this->getHeader('set-cookie') && $this->host == $this->cookie_host)
			{
				$cookies = $this->headers['set-cookie'];
				if (!is_array($cookies)) {
					$cookies = array($cookies);
				}
				
				foreach ($cookies as $cookie)
				{
					if (preg_match('/([^=]+)=([^;]+);/', $cookie, $m)) {
						$this->cookies[$m[1]] = $m[2];
					}
				}
				
				# Record domain of cookies for security reasons
				$this->cookie_host = $this->host;
			}
			
			# If $persist_referers, set the referer ready for the next request
			if ($this->persist_referers) {
				$this->debug('Persisting referer: '.$this->getRequestURL());
				$this->referer = $this->getRequestURL();
			}
			
			# Finally, if handle_redirects and a redirect is sent, do that
			if ($this->handle_redirects)
			{
				if (++$this->redirect_count >= $this->max_redirects)
				{
					$this->redirect_count = 0;
					throw new Exception('Number of redirects exceeded maximum ('.$this->max_redirects.')');
				}
				
				$location = isset($this->headers['location']) ? $this->headers['location'] : '';
				$uri = isset($this->headers['uri']) ? $this->headers['uri'] : '';
				if ($location || $uri)
				{
					if (self::readUrl($location.$uri,$r_ssl,$r_host,$r_port,$r_path,$r_user,$r_pass))
					{
						# If we try to move on another host, remove cookies, user and pass
						if ($r_host != $this->host || $r_port != $this->port) {
							$this->cookies = array();
							$this->setAuthorization(null,null);
							$this->setHost($r_host,$r_port);
						}
						$this->useSSL($r_ssl);
						$this->debug('Redirect to: '.$location.$uri);
						return $this->get($r_path);
					}
				}
				$this->redirect_count = 0;
			}
			return true;
		}
		
		/**
		* Prepare Request
		*
		* Prepares HTTP request and returns an array of HTTP headers.
		*
		* @return array
		*/
		protected function buildRequest()
		{
			$headers = array();
			
			if ($this->proxy_host) {
				$path = $this->getRequestURL();
			} else {
				$path = $this->path;
			}
			
			# Using 1.1 leads to all manner of problems, such as "chunked" encoding
			$headers[] = $this->method.' '.$path.' HTTP/1.0';
			
			$headers[] = 'Host: '.$this->host;
			$headers[] = 'User-Agent: '.$this->user_agent;
			$headers[] = 'Accept: '.$this->accept;
			
			if ($this->use_gzip) {
				$headers[] = 'Accept-encoding: '.$this->accept_encoding;
			}
			$headers[] = 'Accept-language: '.$this->accept_language;
			
			if ($this->referer) {
				$headers[] = 'Referer: '.$this->referer;
			}
			
			# Cookies
			if ($this->cookies) {
				$cookie = 'Cookie: ';
				foreach ($this->cookies as $key => $value) {
					$cookie .= $key.'='.$value.';';
				}
				$headers[] = $cookie;
			}
			
			# X-Forwarded-For
			$xforward= array($_SERVER['REMOTE_ADDR']);
			if ($this->proxy_host) {
				$xforward[] = $_SERVER['SERVER_ADDR'];
			}
			$headers[] = 'X-Forwarded-For: '.implode(', ',$xforward);
			
			# Basic authentication
			if ($this->username && $this->password) {
				$headers[] = 'Authorization: Basic '.base64_encode($this->username.':'.$this->password);
			}
			
			$headers = array_merge($headers,$this->more_headers);
			
			# If this is a POST, set the content type and length
			if ($this->postdata) {
				$content_type = 'Content-Type: application/x-www-form-urlencoded';
				if ($this->post_charset) {
					$content_type .= '; charset='.$this->post_charset;
				}
				$headers[] = $content_type;
				$headers[] = 'Content-Length: '.strlen($this->postdata);
				$headers[] = '';
				$headers[] = $this->postdata;
			}
			
			return $headers;
		}
		
		/**
		* Open Output
		*
		* Initializes output handler if {@link $output} property is not null and
		* is a valid resource stream.
		*/
		protected function outputOpen()
		{
			if ($this->output) {
				if (($this->output_h = @fopen($this->output,'wb')) === false) {
					throw new Exception('Unable to open output stream '.$this->output);
				}
			} else {
				$this->content = '';
			}
		}
		
		/**
		* Close Output
		*
		* Closes output module if exists.
		*/
		protected function outputClose()
		{
			if ($this->output && is_resource($this->output_h)) {
				fclose($this->output_h);
			}
		}
		
		/**
		* Write Output
		*
		* Writes data <var>$c</var> to output module.
		*
		* @param string	$c				Data content
		*/
		protected function outputWrite($c)
		{
			if ($this->output && is_resource($this->output_h)) {
				fwrite($this->output_h,$c);
			} else {
				$this->content .= $c;
			}
		}
		
		/**
		* Get Status
		*
		* Returns the status code of the response - 200 means OK, 404 means file not
		* found, etc.
		*
		* @return string
		*/
		public function getStatus()
		{
			return $this->status;
		}
		
		/**
		* Get Contet
		*
		* Returns the content of the HTTP response. This is usually an HTML document.
		*
		* @return string
		*/
		public function getContent()
		{
			return $this->content;
		}
		
		/**
		* Response Headers
		*
		* Returns the HTTP headers returned by the server as an associative array.
		*
		* @return array
		*/
		public function getHeaders()
		{
			return $this->headers;
		}
		
		/**
		* Response Header
		*
		* Returns the specified response header, or false if it does not exist.
		*
		* @param string	$header			Header name
		* @return string
		*/
		public function getHeader($header)
		{
			$header = strtolower($header);
			if (isset($this->headers[$header])) {
				return $this->headers[$header];
			} else {
				return false;
			}
		}
		
		/**
		* Cookies
		*
		* Returns an array of cookies set by the server.
		*
		* @return array
		*/
		public function getCookies()
		{
			return $this->cookies;
		}
		
		/**
		* Request URL
		*
		* Returns the full URL that has been requested.
		*
		* @return string
		*/
		public function getRequestURL()
		{
			$url = 'http'.($this->use_ssl ? 's' : '').'://'.$this->host;
			if (!$this->use_ssl && $this->port != 80 || $this->use_ssl && $this->port != 443) {
				$url .= ':'.$this->port;
			}
			$url .= $this->path;
			return $url;
		}
		
		/**
		* Sets server host and port.
		*
		* @param string	$host			Server host
		* @param integer	$port			Server port
		*/
		public function setHost($host,$port=80)
		{
			$this->host = $host;
			$this->port = abs((integer) $port);
		}
		
		/**
		* Sets proxy host and port.
		*
		* @param string	host				Proxy host
		* @param integer	port				Proxy port
		*/
		public function setProxy($host,$port='8080')
		{
			$this->proxy_host = $host;
			$this->proxy_port = abs((integer) $port);
		}
		
		/**
		* Sets connection timeout.
		*
		* @param integer	$t				Connection timeout
		*/
		public function setTimeout($t)
		{
			$this->timeout = abs((integer) $t);
		}
		
		/**
		* User Agent String
		*
		* Sets the user agent string to be used in the request. Default is
		* "Clearbricks HTTP Client".
		*
		* @param string	$string			User agent string
		*/
		public function setUserAgent($string)
		{
			$this->user_agent = $string;
		}
		
		/**
		* HTTP Authentication
		*
		* Sets the HTTP authorization username and password to be used in requests.
		* Don't forget to unset this in subsequent requests to different servers.
		*
		* @param string	$username			User name
		* @param string	$password			Password
		*/
		public function setAuthorization($username,$password)
		{
			$this->username = $username;
			$this->password = $password;
		}
		
		/**
		* Add Header
		*
		* Sets additionnal header to be sent with the request.
		*
		* @param string	$header			Full header definition
		*/
		public function setMoreHeader($header)
		{
			$this->more_headers[] = $header;
		}
		
		/**
		* Empty additionnal headers
		*/
		public function voidMoreHeaders()
		{
			$this->more_headers = array();
		}
		
		/**
		* Set Cookies
		*
		* Sets the cookies to be sent in the request. Takes an array of name value
		* pairs.
		*
		* @param array		$array			Cookies array
		*/
		public function setCookies($array)
		{
			$this->cookies = $array;
		}
		
		/**
		* Enable / Disable SSL
		*
		* Sets SSL connection usage.
		*
		* @param boolean	$boolean			Enable/Disable SSL
		*/
		public function useSSL($boolean)
		{
			if ($boolean) {
				if (!in_array('ssl',stream_get_transports())) {
					throw new Exception('SSL support is not available');
				}
				$this->use_ssl = true;
			} else {
				$this->use_ssl = false;
			}
		}
		
		/**
		* Use Gzip
		*
		* Specifies if the client should request gzip encoded content from the server
		* (saves bandwidth but can increase processor time). Default behaviour is
		* false.
		*
		* @param boolean	$boolean			Enable/Disable Gzip
		*/
		public function useGzip($boolean)
		{
			$this->use_gzip = (boolean) $boolean;
		}
		
		/**
		* Persistant Cookies
		*
		* Specify if the client should persist cookies between requests. Default
		* behaviour is true.
		*
		* @param boolean	$boolean			Enable/Disable Persist Cookies
		*/
		public function setPersistCookies($boolean)
		{
			$this->persist_cookies = (boolean) $boolean;
		}
		
		/**
		* Persistant Referrers
		*
		* Specify if the client should use the URL of the previous request as the
		* referral of a subsequent request. Default behaviour is true.
		*
		* @param boolean	$boolean			Enable/Disable Persistant Referrers
		*/
		public function setPersistReferers($boolean)
		{
			$this->persist_referers = (boolean) $boolean;
		}
		
		/**
		* Enable / Disable Redirects
		*
		* Specify if the client should automatically follow redirected requests.
		* Default behaviour is true.
		*
		* @param boolean	$boolean			Enable/Disable Redirects
		*/
		public function setHandleRedirects($boolean)
		{
			$this->handle_redirects = (boolean) $boolean;
		}
		
		/**
		* Maximum Redirects
		*
		* Set the maximum number of redirects allowed before the client quits
		* (mainly to prevent infinite loops) Default is 5.
		*
		* @param integer	$num				Maximum redirects value
		*/
		public function setMaxRedirects($num)
		{
			$this->max_redirects = abs((integer) $num);
		}
		
		/**
		* Headers Only
		*
		* If true, the client only retrieves the headers from a page. This could be
		* useful for implementing things like link checkers. Defaults to false.
		*
		* @param boolean	$boolean			Enable/Disable Headers Only
		*/
		public function setHeadersOnly($boolean)
		{
			$this->headers_only = (boolean) $boolean;
		}
		
		/**
		* Debug mode
		*
		* Should the client run in debug mode? Default behaviour is false.
		*
		* @param boolean	$boolean			Enable/Disable Debug Mode
		*/
		public function setDebug($boolean)
		{
			$this->debug = (boolean) $boolean;
		}
		
		/**
		* Set Output
		*
		* Output module init. If <var>$out</var> is null, then output will be
		* directed to STDOUT.
		*
		* @param string|null	$out			Output stream
		*/
		public function setOutput($out)
		{
			$this->output = $out;
		}
		
		/**
		* Quick Get
		*
		* Static method designed for running simple GET requests. Returns content or
		* false on failure.
		*
		* @param string	$url				Request URL
		* @param string	$output			Optionnal output stream
		* @return string|false
		*/
		public static function quickGet($url,$output=null)
		{
			if (($client = self::initClient($url,$path)) === false) {
				return false;
			}
			$client->setOutput($output);
			$client->get($path);
			return $client->getStatus() == 200 ? $client->getContent() : false;
		}
		
		/**
		* Quick Post
		*
		* Static method designed for running simple POST requests. Returns content or
		* false on failure.
		*
		* @param string	$url				Request URL
		* @param string	$data			Array of parameters
		* @param string	$output			Optionnal output stream
		* @return string
		*/
		public static function quickPost($url,$data,$output=null)
		{
			if (($client = self::initClient($url,$path)) === false) {
				return false;
			}
			$client->setOutput($output);
			$client->post($path,$data);
			return $client->getStatus() == 200 ? $client->getContent() : false;
		}
		
		/**
		* Quick Init
		*
		* Returns a new instance of the class. <var>$path</var> is an output variable.
		*
		* @param string	$url				Request URL
		* @param string	&$path			Resulting path
		* @return netHttp
		*/
		public static function initClient($url,&$path)
		{
			if (!self::readUrl($url,$ssl,$host,$port,$path,$user,$pass)) {
				return false;
			}
			
			$client = new self($host,$port);
			$client->useSSL($ssl);
			$client->setAuthorization($user,$pass);
			
			return $client;
		}
		
		/**
		* Read URL
		*
		* Parses an URL and fills <var>$ssl</var>, <var>$host</var>, <var>$port</var>,
		* <var>$path</var>, <var>$user</var> and <var>$pass</var> variables. Returns
		* true on succes.
		*
		* @param string	$url				Request URL
		* @param boolean	&$ssl			true if HTTPS URL
		* @param string	&$host			Host name
		* @param string	&$port			Server Port
		* @param string	&$path			Path
		* @param string	&$user			Username
		* @param string	&$pass			Password
		* @return boolean
		*/
		public static function readURL($url,&$ssl,&$host,&$port,&$path,&$user,&$pass)
		{
			$bits = parse_url($url);
			
			if (empty($bits['host'])) {
				return false;
			}
			
			if (empty($bits['scheme']) || !preg_match('%^http[s]?$%',$bits['scheme'])) {
				return false;
			}
			
			$scheme = isset($bits['scheme']) ? $bits['scheme'] : 'http';
			$host = isset($bits['host']) ? $bits['host'] : null;
			$port = isset($bits['port']) ? $bits['port'] : null;
			$path = isset($bits['path']) ? $bits['path'] : '/';
			$user = isset($bits['user']) ? $bits['user'] : null;
			$pass = isset($bits['pass']) ? $bits['pass'] : null;
			
			$ssl = $scheme == 'https';
			
			if (!$port) {
				$port = $ssl ? 443 : 80;
			}
			
			if (isset($bits['query'])) {
				$path .= '?'.$bits['query'];
			}
			
			return true;
		}
		
		/**
		* Debug
		*
		* This method is the method the class calls whenever there is debugging
		* information available. $msg is a debugging message and $object is an
		* optional object to be displayed (usually an array). Default behaviour is to
		* display the message and the object in a red bordered div. If you wish
		* debugging information to be handled in a different way you can do so by
		* creating a new class that extends HttpClient and over-riding the debug()
		* method in that class.
		* 
		* @param string	$msg				Debug message
		* @param mixed		$object			Variable to print_r
		*/
		protected function debug($msg,$object=false)
		{
			if ($this->debug) {
				echo "-----------------------------------------------------------\n";
				echo '-- netHttp Debug: '.$msg."\n";
				if ($object) {
					print_r($object);
					echo "\n";
				}
				echo "-----------------------------------------------------------\n\n";
			}
		}
	}
}

# Compatibility to Incutio HttpClient class
# This will be removed soon!
/** @ignore */
if (class_exists('netHttp'))
{
	class HttpClient extends netHttp
	{
		public function getError()
		{
			return null;
		}
	}
}
?>