Need help improving daily visitors counter script

<?php include("counter.txt"); ?>
<IMG border=0 width=1 height=1 src="daily_visitors/daily_visitors.php" >




<?php

//   Daily visitors counter script


    // Holds the current day of year as a numerical value 1 - 365
    $day = $PATH_INFO."day.txt";

    // Are counter value txt file
    $counter = $PATH_INFO."counter.txt";

    // Are IP address value txt file
    $ip = $PATH_INFO."ip.txt";

    // Number of previous IP address values to keep in txt file
    $ip_block = 200;


    $fp = fopen("$ip", "a");
    if (IsSet($REMOTE_ADDR))
    fwrite($fp, "$REMOTE_ADDR\n");

    else
    {
        $REMOTE_ADDR = 0;

    } // end else
    fclose($fp);


    $fp = fopen($ip, "r");
    $fr = fread($fp, filesize($ip));

    // explode $REMOTE_ADDR and place in a array
    $line = explode("$REMOTE_ADDR", $fr);

    // $i == $REMOTE_ADDR +1 for are \n
    for($i = 0; $i < count($line); $i++);
    fclose($fp);


    // Line numbers
    $fcontents = file ("$ip");
    while (list ($line_num, $line) = each ($fcontents))
    {

        if ($line_num > $ip_block)
        {
            $fp = fopen("$ip", "w");
            fwrite($fp, "");
            fclose($fp);
        } // end if

    } // end while



    if ($i > 2)
    {
        // Are IP address has been here recently
        exit;
    }


    else
    {

        // Open are day of year file
        $fd = fopen("$day", "r");
        $old = fgets($fd, 1024);
        fclose($fd);

        // If the day of year file is empty
        // write day of year as a numerical value 1 - 365
        If ($old == "")
        {
            $r = date("z");
            $fs = fopen($day, "w");
            fwrite($fs, "$r");
            fclose ($fs);
        } // end if

        // Increment 'z' day of year number
        If ($old == date("z"))
        {
            $o = 1 + date("z");
            $fs = fopen($day, "w");
            fwrite($fs, $o);
            fclose ($fs);

            // Reset are counter
            $fr = fopen("$counter", "w");
            fwrite($fr, "1");
            fclose($fr);
        } // end if

        else
        {
            // Read Counter
            $fp = fopen("$counter", "r");
            $count = fgets($fp, 1024);
            fclose($fp);

            // Current counter file empty so writing a 1
            If ($count == "")
            {
                $fr = fopen("$counter", "w");
                fwrite($fr, "1");
                fclose($fr);
            } // end if

            // Increment counter number
            $fw = fopen("$counter", "w");
            $output = $count++;
            $countnew = fputs($fw, $count);
            fclose($fw);
        } // end else


    } // end else



?>