process data

<?php
//codice captcha
        function Random()
        {
        $chars = "ABCDEFGHJKLMNPQRSTUVWZYZ23456789";
        srand((double)microtime()*1000000);
        $i = 0;
        $pass = '' ;
        while ($i <= 4)
            {
            $num = rand() % 32;
            $tmp = substr($chars, $num, 1);
            $pass = $pass . $tmp;
            $i++;
            }
        return $pass;
        }
    $random_code = Random();


class Comment
{
    private $data = array();

    public function __construct($row)
    {
        /*
        /   The constructor
        */

        $this->data = $row;
    }

    public function markup()
    {
        /*
        /   This method outputs the XHTML markup of the comment
        */

        // Setting up an alias, so we don't have to write $this->data every time:
        $d = &$this->data;

        $link_open = '';
        $link_close = '';

        if($d['url']){

            // If the person has entered a URL when adding a comment,
            // define opening and closing hyperlink tags

            $link_open = '<a href="'.$d['url'].'" rel="nofollow">';
            $link_close =  '</a>';
        }

        // Converting the time to a UNIX timestamp:
        $d['dt'] = strtotime($d['dt']);

        // Needed for the default gravatar image:
        $url = 'http://'.dirname($_SERVER['SERVER_NAME'].$_SERVER["REQUEST_URI"]).'/img/default_avatar.gif';

        return '

            <div class="comment">
                <div class="avatar">
                    '.$link_open.'
                    <img src="http://www.gravatar.com/avatar/'.md5($d['email']).'?size=50&amp;default='.urlencode($url).'" />
                    '.$link_close.'
                </div>

                <div class="name">'.$link_open.$d['name'].$link_close.' <i>(da/from '.$d['location'].' )</i></div>
                <div class="date" title="Added at '.date('H:i \o\n d M Y',$d['dt']).'">'.date('d M Y',$d['dt']).'</div>
                <p>'.$d['body'].'</p>

            </div>
        ';
    }

    public static function validate(&$arr)
    {
        /*
        /   This method is used to validate the data sent via AJAX.
        /
        /   It return true/false depending on whether the data is valid, and populates
        /   the $arr array passed as a paremter (notice the ampersand above) with
        /   either the valid input data, or the error messages.
        */

        $errors = array();
        $data   = array();

        // Using the filter_input function introduced in PHP 5.2.0

        if(!($data['email'] = filter_input(INPUT_POST,'email',FILTER_VALIDATE_EMAIL)))
        {
            $errors['email'] = 'Please enter a valid Email.';
        }

        if(!($data['url'] = filter_input(INPUT_POST,'url',FILTER_VALIDATE_URL)))
        {
            // If the URL field was not populated with a valid URL,
            // act as if no URL was entered at all:

            $url = '';
        }

        // Using the filter with a custom callback function:

        if(!($data['body'] = filter_input(INPUT_POST,'body',FILTER_CALLBACK,array('options'=>'Comment::validate_text'))))
        {
            $errors['body'] = 'Please enter a comment.';
        }

        if(!($data['name'] = filter_input(INPUT_POST,'name',FILTER_CALLBACK,array('options'=>'Comment::validate_text'))))
        {
            $errors['name'] = 'Please enter a name.';
        }

        if(!($data['location'] = filter_input(INPUT_POST,'location',FILTER_CALLBACK,array('options'=>'Comment::validate_text'))))
        {
            $errors['location'] = 'Please enter your location.';
        }

print_r($_POST); die('done here');
        if(!($data['security_code'] = filter_input(INPUT_POST,'security_code',FILTER_CALLBACK,array('options'=>'Comment::validate_text'))))
        {
        $errors['security_code'] = '<br />You did not enter the validation code.';
        }
        if($data['security_code'] != $randomness)
        {
        $errors['security_code'] = '<br />You entered '.$randomness.' the validation code incorrectly.';
        }



        if(!empty($errors)){

            // If there are errors, copy the $errors array to $arr:

            $arr = $errors;
            return false;
        }

        // If the data is valid, sanitize all the data and copy it to $arr:

        foreach($data as $k=>$v){
            $arr[$k] = mysql_real_escape_string($v);
        }

        // Ensure that the email is lower case:

        $arr['email'] = strtolower(trim($arr['email']));

        // Prima lettera del nome e della location in maiuscolo:
        $arr['name'] = ucwords(trim($arr['name']));
        $arr['location'] = ucwords(trim($arr['location']));

        return true;

    }

    private static function validate_text($str)
    {
        /*
        /   This method is used internally as a FILTER_CALLBACK
        */

        if(mb_strlen($str,'utf8')<1)
            return false;

        // Encode all html special characters (<, >, ", & .. etc) and convert
        // the new line characters to <br> tags:

        $str = nl2br(htmlspecialchars($str));

        // Remove the new line characters that are left
        $str = str_replace(array(chr(10),chr(13)),'',$str);

        return $str;
    }

}

?>