<?
/**
 * FTP Class 
 * version 0.50
 * Copyright Raditha Dissanayake 2003
 * Licence Jabber Open Source Licence.
 *
 * vist http://www.raditha.com/ for updates.
 */

DEFINE (FPERM,0);
DEFINE (FINODE,1);
DEFINE (FUID,2);
DEFINE (FGID,3);
DEFINE (FSIZE,4);
DEFINE (FMONTH,5);
DEFINE (FDAY,7);
DEFINE (FTIME,7);
DEFINE (FNAME,8);

class FTP {

	var $host;
	
	var $sock;
	var $data_sock;
	
	var $errno;
	var $errstr;
	var $message;

	var $user="anonymous";
	var $pass="nobody@nobody.com";
		
	var $enable_log=0;
	

	/**
	 * constructor
	 */
	function FTP($host,$port=21)
	{
		$this->log("host = $host, $port=$port");
		$this->host = $host;
		$this->port = $port;
	}
	
	/**
	 * connects to the server and returns the socket which wil
	 * be null if the connection failed. In which case you should
	 * look at the $errno and $errstr variables.
	 */
	function connect()
	{
		
		$this->sock = @fsockopen($this->host,$this->port,&$this->errno,&$this->errstr,30);
		@set_socket_blocking($this->sock,false);
		return $this->sock;
	}


	/**
	 * will read data from the socket. Since we are using non blocking 
	 * mode, if we attempt to read the data even a millisecond before 
	 * it becomes available, the method just returns null.
	 *
	 * So what's the cure? we will loop for a while and try to read it
	 * in multiple times. Note that if we used blocking mode there may
	 * be instances when this function NEVER returns.
	 */
	function sock_read($i=0)
	{
		$s = fgets($this->sock,4096);

		$this->log($s);
		if($s=='')
		{
			if($i==30)
			{
				return "";
			}
			else
			{
				sleep(1);
				return $this->sock_read($i+1);
			}
		}
		return $s;
	}

	/**
	 * this is a hack. We are just checking if the server returns a 
	 * 5xx number which indentifies an error. We assume that 
	 * everything else is ok. Which may not always be true. That's 
	 * some functionality which should be improved in the future.
	 */
	 
	function is_ok()
	{
		$this->message = $this->sock_read();

		if($this->message == "" || preg_match('/^5/',$this->message) )
		{
			return 0;
		}
		else
		{
			return 1;
		}
	}

	/**
	 * Utility method so that we can take care of logging and
	 * adding the carriage return etc.
	 */
	function sock_write($s)
	{
		@fputs($this->sock,"$s\n");
		$this->log($s);
		
	}

	/**
	 * retrieves a listing of the given directory or the current
	 * working directory if no path has been specified. Returns
	 * a string which contains all the directory entries separated
	 * by new lines.
	 */
	function dir_list($path="")
	{
		$s="";
		if($this->pasv())
		{
			if($path == '')
			{
				$this->sock_write("LIST");
			}
			else
			{
				$this->sock_write("LIST $path");
			}
			if($this->is_ok())
			{
				while(true)
				{
					$line = fgets($this->data_sock);
					$s .= $line;
					if($line =='')
						break;
				}
			}
		}
		return $s;
	}
	
	/**
	 * this function will return a handle that can be used to 
	 * retrieve a file on the FTP host. 
	 */
	function retr($path)
	{
		if($this->pasv())
		{
			$this->sock_write("RETR $path");
			if($this->is_ok())
			{
				return $this->data_sock;
			}
		}
		return "";
	}
	/**
	 * establishes a passive mode data connection
	 */
	function pasv()
	{
		$this->sock_write("PASV");
		if($this->is_ok())
		{
			$offset = strpos($this->message,"(");
			
			$s = substr($this->message,++$offset,strlen($this->messsage)-2);
			$parts = split(",",trim($s));
			$data_host = "$parts[0].$parts[1].$parts[2].$parts[3]";
			$data_port = ((int)$parts[4] << 8) + (int) $parts[5];
		
			$this->data_sock = fsockopen($data_host,$data_port,&$errno,&$errstr,30);
			return $this->data_sock;
		}
		return "";
	}
	
	
	/**
	 * log the user in with the given username and password, default
	 * to annoymous with a dud email address if no username password
	 * have been given.
	 */
	function login($user="",$pass="")
	{
		/* no overloading in PHP */
		if($user=='') $user = $this->user;
		if($pass=='') $pass = $this->pass;
		
		$this->sock_write("USER $user");
		if($this->is_ok())
		{
			$this->sock_write("PASS $pass");

			if($this->check_reply("230"))
			{
				
				return 1;
			}
		}

		ob_flush();
		return 0;
	}
	
	function check_reply($code)
	{
		if($code=='230')
		{
			while(1)
			{
				if($this->is_ok())
				{
					if( preg_match('/^230 /',$this->message))
					{
						return 1;
					}
					
				}						
				else
				{
					return 0;
				}

			}
		}
	}
	/**
	 * change this method to suite your log system.
	 * be sure to setting the $enable_log to 1 
	 */
	function log($str)
	{
		if($this->enable_log)
		{
			echo "$str<br>\n";
		}
	}
	
	function set_user($user)
	{
		$this->user=$user;
	}
	function set_pass($pass)
	{
		$this->pass =$pass;
	}

	
}

/**
 * this is not a member of the FTP class because it does not
 * work directly with the FTP server in any way. It will instead
 * process the output from the FTP server.
 *
 * Notice that the Table does not have the table start and end
 * tag. this is to allow you to create a header outside of this
 * function.
 *
 * Overall i think template schemes of this nature suck but to
 * use my beloved XSLT would be overkill.
 */
function show_list($data)
{

	$list = split("\n",$data);

	$pattern = "/[dwrx\-]{10}/";
	
	$list = array_slice($list,1,count($list)-1);
	foreach($list as $file)
	{
		
		$file = preg_split("/ /",$file,20,PREG_SPLIT_NO_EMPTY);
		
		/*
		 * directory download has to be implemented in a different manner
		 * so we will just ignore directories for now.
		 */
		if(preg_match('/^d/',$file[FPERM]))
		{
			$downlink = "javascript:alert('We will CWD functionality in the third part of this tutorial coming up soon')";	
		}
		else
		{
			$downlink = "getfile.php?filename=". urlencode("$path".$file[FNAME]);
		}
		
		printf('<tr><td class="cell1">%s</td><td class="cell1">%s</td>
					<td class="cell1">%s</td><td class="cell1">%s</td>
					<td class="cell1">%s %s %s</td>
					<td  class="cell1"><a href="%s">%s</a></td>
				</tr>',
				$file[FPERM],$file[FUID],$file[FGID], $file[FSIZE],
				$file[FMONTH],$file[FDAY],$file[FTIME],
				$downlink, $file[FNAME]);

	}
}


?>