Subversion Repositories Applications.gtt

<?php
/*
 * This work is hereby released into the Public Domain.
 * To view a copy of the public domain dedication,
 * visit http://creativecommons.org/licenses/publicdomain/ or send a letter to
 * Creative Commons, 559 Nathan Abbott Way, Stanford, California 94305, USA.
 *
 */

require_once dirname(__FILE__)."/Image.class.php";

/**
 * AntiSpam
 * String printed on the images are case insensitive.
 *
 * @package Artichow
 */
class awAntiSpam extends awImage {

        /**
         * Anti-spam string
         *
         * @var string
         */
        protected $string;

        /**
         * Noise intensity
         *
         * @var int
         */
        protected $noise = 0;
                
        /**
         * Construct a new awAntiSpam image
         *
         * @param string $string A string to display
         */
        public function __construct($string = '') {
        
                parent::__construct();
                
                $this->string = (string)$string;
        
        }
        
        /**
         * Create a random string
         *
         * @param int $length String length
         * @return string String created
         */
        public function setRand($length) {
        
                $length = (int)$length;
        
                $this->string = '';
                
                $letters = 'aAbBCDeEFgGhHJKLmMnNpPqQRsStTuVwWXYZz2345679';
                $number = strlen($letters);
        
                for($i = 0; $i < $length; $i++) {
                        $this->string .= $letters{mt_rand(0, $number - 1)};
                }
                
                return $this->string;
                
        }
        
        /**
         * Set noise on image
         *
         * @param int $nois Noise intensity (from 0 to 10)
         */
        public function setNoise($noise) {
                if($noise < 0) {
                        $noise = 0;
                }
                if($noise > 10) {
                        $noise = 10;
                }
                $this->noise = (int)$noise;
        }
        
        /**
         * Save string value in session
         * You can use check() to verify the value later
         *
         * @param string $qName A name that identify the anti-spam image
         */
        public function save($qName) {
                $this->session();
                $session = 'artichow_'.(string)$qName;
                $_SESSION[$session] = $this->string;
        }
        
        /**
         * Verify user entry
         *
         * @param string $qName A name that identify the anti-spam image
         * @param string $value User-defined value
         * @param bool $case TRUE for case insensitive check, FALSE for case sensitive check ? (default to TRUE)
         * @return bool TRUE if the value is correct, FALSE otherwise
         */
        public function check($qName, $value, $case = TRUE) {
        
                $this->session();
        
                $session = 'artichow_'.(string)$qName;
                
                return (
                        array_key_exists($session, $_SESSION) === TRUE and
                        $case ?
                                (strtolower($_SESSION[$session]) === strtolower((string)$value)) :
                                ($_SESSION[$session] === (string)$value)
                );
        
        }
        
        /**
         * Draw image
         */
        public function draw() {

                $fonts = array(
                        'Tuffy',
                        'TuffyBold',
                        'TuffyItalic',
                        'TuffyBoldItalic'
                );
                
                $sizes = array(12, 12.5, 13, 13.5, 14, 15, 16, 17, 18, 19);
                
                $widths = array();
                $heights = array();
                $texts = array();
                
                // Set up a temporary driver to allow font size calculations...
                $this->setSize(10, 10);
                $driver = $this->getDriver();
                
                for($i = 0; $i < strlen($this->string); $i++) {
                
                        $fontKey = array_rand($fonts);
                        $sizeKey = array_rand($sizes);
                
                        $font = new awTTFFont(
                                $fonts[$fontKey], $sizes[$sizeKey]
                        );
                        
                        $text = new awText(
                                $this->string{$i},
                                $font,
                                NULL,
                                mt_rand(-15, 15)
                        );
                        
                        $widths[] = $driver->getTextWidth($text);
                        $heights[] = $driver->getTextHeight($text);
                        $texts[] = $text;
                
                }
                
                // ... and get rid of it.
                $this->driver = NULL;
                
                $width = array_sum($widths);
                $height = array_max($heights);
                
                $totalWidth = $width + 10 + count($texts) * 10;
                $totalHeight = $height + 20;
                
                $this->setSize($totalWidth, $totalHeight);
        
                $this->create();
                
                for($i = 0; $i < strlen($this->string); $i++) {
                
                        $this->driver->string(
                                $texts[$i],
                                new awPoint(
                                        5 + array_sum(array_slice($widths, 0, $i)) + $widths[$i] / 2 + $i * 10,
                                        10 + ($height - $heights[$i]) / 2
                                )
                        );
                
                }
                
                $this->drawNoise($totalWidth, $totalHeight);
                
                $this->send();
                
        }
        
        protected function drawNoise($width, $height) {
        
                $points = $this->noise * 30;
                $color = new awColor(0, 0, 0);
                
                for($i = 0; $i < $points; $i++) {
                        $this->driver->point(
                                $color,
                                new awPoint(
                                        mt_rand(0, $width),
                                        mt_rand(0, $height)
                                )
                        );
                }
        
        }
        
        protected function session() {
        
                // Start session if needed
                if(!session_id()) {
                        session_start();
                }
                
        }

}

registerClass('AntiSpam');
?>