<?php
/**
 * visualCaptcha Captcha class by emotionLoop - 2013.08.17
 *
 * This class handles a visual image captcha system.
 *
 * This license applies to this file and others without reference to any other license.
 *
 * @author emotionLoop | http://emotionloop.com
 * @link http://visualcaptcha.net
 * @package visualCaptcha
 * @license GNU GPL v3
 * @version 4.2.0
 */
namespace visualCaptcha;

// 3BA .. patch for Wordpress
if (function_exists('plugins_url')) {
define('IMAGE_URL', plugins_url( '../image.php', __FILE__ ));
define('AUDIO_URL',plugins_url( '../audio.php', __FILE__ ));
define('IMAGES_PATH',plugins_url('../images/visualcaptcha/',__FILE__));
}
else {
    define('IMAGE_URL', 'image.php'); // Probably won't work all the time ...
    define('AUDIO_URL', 'audio.php'); // Probably won't work all the time ...
    define('IMAGES_PATH','images/visualcaptcha/');
    
}

// End 3BA
class Captcha {
	private $formId = 'frm_captcha';
	private $type = 0;
	private $fieldName = 'captcha-value';
	private $accessibilityFieldName = 'captcha-accessibility-value';
	private $html = '';
	private $hash = '';
	private $hashSalt = '';
	private $answers = array();
	private $options = array();
	private $optionsProperties = array();
	private $accessibilityOptions = array();
	private $accessibilityFile = '';
	private $accessibilityAnswer = '';
	private $value = '';
	private $valueProperties = array();
	private $htmlClass = 'visualcaptcha.class.html.php'; // 3BA:: Modified path
	public static $imagesPath = IMAGES_PATH;
	public static $audiosPath = 'audio/visualcaptcha/';
	public static $imageFile = IMAGE_URL;
	public static $audioFile = AUDIO_URL;

	public function __construct( $formId = NULL, $type = NULL, $fieldName = NULL, $accessibilityFieldName = NULL ) {
		$this->hashSalt = 'emotionLoop::' . $_SERVER['REMOTE_ADDR'] . '::visualCaptcha::';
		$this->hash = sha1( $this->hashSalt . $this->nonceTick(1800) . '::tick' );
		
		if ( ! is_null($formId) ) {
			$this->formId = $formId;
		}
		
		if ( ! is_null($type) ) {
			$this->type = (int) $type;
		} else {
			$this->type = 0;
		}

		if ( ! is_null($fieldName) ) {
			$this->fieldName = $fieldName;
		}

		if ( ! is_null($accessibilityFieldName) ) {
			$this->accessibilityFieldName = $accessibilityFieldName;
		}

		// Setup Image Names here: stringID, array(ImagePath, ImageName/Text to show)
		$this->answers = array(
			'airplane' => array(self::$imagesPath . 'airplane.png', 'Airplane'),
			'balloons' => array(self::$imagesPath . 'balloons.png', 'Balloons'),
			'camera'   => array(self::$imagesPath . 'camera.png',   'Camera'),
			'car'	  => array(self::$imagesPath . 'car.png',	  'Car'),
			'cat'	  => array(self::$imagesPath . 'cat.png',	  'Cat'),
			'chair'	=> array(self::$imagesPath . 'chair.png',	'Chair'),
			'clip'	 => array(self::$imagesPath . 'clip.png',	 'Clip'),
			'clock'	=> array(self::$imagesPath . 'clock.png',	'Clock'),
			'cloud'	=> array(self::$imagesPath . 'cloud.png',	'Cloud'),
			'computer' => array(self::$imagesPath . 'computer.png', 'Computer'),
			'envelope' => array(self::$imagesPath . 'envelope.png', 'Envelope'),
			'eye'	  => array(self::$imagesPath . 'eye.png',	  'Eye'),
			'flag'	 => array(self::$imagesPath . 'flag.png',	 'Flag'),
			'folder'   => array(self::$imagesPath . 'folder.png',   'Folder'),
			'foot'	 => array(self::$imagesPath . 'foot.png',	 'Foot'),
			'graph'	=> array(self::$imagesPath . 'graph.png',	'Graph'),
			'house'	=> array(self::$imagesPath . 'house.png',	'House'),
			'key'	  => array(self::$imagesPath . 'key.png',	  'Key'),
			'lamp'	 => array(self::$imagesPath . 'lamp.png',	 'Lamp'),
			'leaf'	 => array(self::$imagesPath . 'leaf.png',	 'Leaf'),
			'lock'	 => array(self::$imagesPath . 'lock.png',	 'Lock'),
			'magnifying-glass' => array(self::$imagesPath . 'magnifying-glass.png', 'Magnifying Glass'),
			'man'	  => array(self::$imagesPath . 'man.png',	  'Man'),
			'music-note' => array(self::$imagesPath . 'music-note.png', 'Music Note'),
			'pants'	=> array(self::$imagesPath . 'pants.png',	'Pants'),
			'pencil'   => array(self::$imagesPath . 'pencil.png',   'Pencil'),
			'printer'  => array(self::$imagesPath . 'printer.png',  'Printer'),
			'robot'	=> array(self::$imagesPath . 'robot.png',	'Robot'),
			'scissors' => array(self::$imagesPath . 'scissors.png', 'Scissors'),
			'sunglasses' => array(self::$imagesPath . 'sunglasses.png', 'Sunglasses'),
			'tag'	  => array(self::$imagesPath . 'tag.png',	  'Tag'),
			'tree'	 => array(self::$imagesPath . 'tree.png',	 'Tree'),
			'truck'	=> array(self::$imagesPath . 'truck.png',	'Truck'),
			'tshirt'   => array(self::$imagesPath . 'tshirt.png',   'T-Shirt'),
			'umbrella' => array(self::$imagesPath . 'umbrella.png', 'Umbrella'),
			'woman'	=> array(self::$imagesPath . 'woman.png',	'Woman'),
			'world'	=> array(self::$imagesPath . 'world.png',	'World'),
		);

		// Setup Accessibility Questions here: array(Answer, MP3 Audio file). You can repeat answers, but it's safer if you don't.
		// You can generate MP3 & Ogg audio files easily using http://stuffthatspins.com/stuff/php-TTS/index.php
		$this->accessibilityOptions = array(
			array('10', self::$audiosPath . '5times2.mp3'),
			array('20', self::$audiosPath . '2times10.mp3'),
			array('6', self::$audiosPath . '5plus1.mp3'),
			array('7', self::$audiosPath . '4plus3.mp3'),
			array('4', self::$audiosPath . 'add3to1.mp3'),
			array('green', self::$audiosPath . 'addblueandyellow.mp3'),
			array('white', self::$audiosPath . 'milkcolor.mp3'),
			array('2', self::$audiosPath . 'divide4by2.mp3'),
			array('yes', self::$audiosPath . 'sunastar.mp3'),
			array('no', self::$audiosPath . 'yourobot.mp3'),
			array('12', self::$audiosPath . '6plus6.mp3'),
			array('100', self::$audiosPath . '99plus1.mp3'),
			array('blue', self::$audiosPath . 'skycolor.mp3'),
			array('3', self::$audiosPath . 'after2.mp3'),
			array('24', self::$audiosPath . '12times2.mp3'),
			array('5', self::$audiosPath . '4plus1.mp3'),
		);
	}
	
	public function show() {
		$this->setNewValue();
		
		// Include visualCaptcha HTML class
		require_once( $this->htmlClass );

		$this->html = HTML::get( $this->type, $this->fieldName, $this->accessibilityFieldName, $this->formId, $this->getText(), $this->options );

		echo $this->html;
	}
	
	public function isValid() {
		// "Normal" option
		if ( isset($_POST[$this->fieldName]) && isset($_SESSION[$this->hash]) && ($_POST[$this->fieldName] === $_SESSION[$this->hash]) ) {
			return true;
		}

		// Accessibility option
		if ( isset($_POST[$this->accessibilityFieldName]) && isset($_SESSION[$this->hash.'::accessibility']) && ($this->encrypt( mb_strtolower($_POST[$this->accessibilityFieldName]) ) === $_SESSION[$this->hash.'::accessibility']) ) {
			return true;
		}
		return false;
	}
	
	private function setNewValue() {
		$this->answers = $this->shuffle( $this->answers );

		// Generate and Store a new session "id"
		$_SESSION[ $this->hash . '::requestSession' ] = sha1( $this->hash . '::' . microtime() );

		$i = 0;
		switch ( $this->type ) {
			case 0:// Horizontal
				$limit = 5;
			break;
			case 1:// Vertical
				$limit = 4;
			break;
		}
		
		// Define the index that will have the right answer
		$rnd = rand( 0, $limit - 1 );
		
		foreach ( $this->answers as $answer => $answerProps ) {
			if ( $i >= $limit ) {
				continue;
			}

			$encryptedAnswer = $this->encrypt( $answer );

			$this->options[] = $encryptedAnswer;
			$this->optionsProperties[ $encryptedAnswer ] = $answerProps;

			// Record this option as the answer
			if ( $i === $rnd ) {
				$_SESSION[ $this->hash ] = $encryptedAnswer;
				$this->value = $encryptedAnswer;
				$this->valueProperties = $answerProps;
			}

			++$i;
		}

		// Mess with the ordering
		shuffle( $this->options );

		// Store the options in the session
		$_SESSION[ $this->hash . '::options' ] = $this->options;
		$_SESSION[ $this->hash . '::optionsProperties' ] = $this->optionsProperties;

		// Accessibility option. Set question file and answer, encrypted
		$this->accessibilityOptions = $this->shuffle( $this->accessibilityOptions );

		$limit = count( $this->accessibilityOptions );

		$rnd = rand(0, $limit-1);

		$this->accessibilityAnswer = $this->encrypt( $this->accessibilityOptions[ $rnd ][ 0 ] );
		$this->accessibilityFile = $this->accessibilityOptions[ $rnd ][ 1 ];

		$_SESSION[ $this->hash . '::accessibility' ] = $this->accessibilityAnswer;
		$_SESSION[ $this->hash . '::accessibilityFile' ] = $this->accessibilityFile;
	}
	
	private function getValue() {
		return $this->value;
	}
	
	private function getImage() {
		return $this->valueProperties[ 0 ];
	}
	
	private function getText() {
		return $this->valueProperties[ 1 ];
	}
	
	/**
	 * Get the time-dependent variable for nonce creation.
	 * This function is based on Wordpress' wp_nonce_tick().
	 *
	 * @since 1.1
	 * @param $life Integer number of seconds for the tick to be valid. Defaults to 86400 (24 hours)
	 * @return int
	 */
	private function nonceTick( $life = 86400 ) {
		return ceil( time() / $life );
	}
	
	/**
	 * Private shuffle() method. Shuffles an associative array. If $list is not an array, it returns $list without any modification.
	 *
	 * @since 1.1
	 * @param $list Array to shuffle.
	 * @return $random Array shuffled array.
	 */
	private function shuffle( $list ) {
		if ( ! is_array($list) ) {
			return $list;
		}
		$keys = array_keys( $list );
		shuffle( $keys );
		$random = array();
		
		foreach ( $keys as $key ) {
			$random[ $key ] = $list[ $key ];
		}
		
		return $random;
	}

	/**
	 * Private encrypt method. Encrypts a string using sha1()
	 *
	 * @since 4.0
	 * @param $string String to encrypt
	 * @return $encryptedString String encrypted
	 */
	private function encrypt( $string ) {
		$encryptedString = sha1( $this->hashSalt . $this->nonceTick(1800) . '::encrypt::' . $string . '::' . $this->getRequestSession() );
		return $encryptedString;
	}

	/**
	 * Public getAudioFilePath method. Returns the current audio file path in the session, if set
	 *
	 * @since 4.0
	 * @return String with the path to the current acessibility audio file
	 */
	public function getAudioFilePath() {
		return $_SESSION[ $this->hash . '::accessibilityFile' ];
	}

	/**
	 * Public getImageFilePath method. Returns the image file path in the session, for the given index
	 *
	 * @since 4.1
	 * @param $i Integer index number
	 * @param $getRetina Boolean should the images be @2x or not. Defaults to false
	 * @return String with the path to the current image file according to the index
	 */
	public function getImageFilePath( $i, $getRetina = false ) {
		$imageEncryptedValue = $_SESSION[ $this->hash . '::options' ][ $i ];
		$imagePath = $_SESSION[ $this->hash . '::optionsProperties' ][ $imageEncryptedValue ][ 0 ];

		if ( ! $getRetina ) {
			return $imagePath;
		} else {
			$retinaPath = str_replace( '.png', '@2x.png', $imagePath );
			return $retinaPath;
		}
	}

	/**
	 * Private getRequestSession method. Returns the current request's session, if set
	 *
	 * @since 4.2
	 * @return String with the value for the current session
	 */
	private function getRequestSession() {
		return $_SESSION[ $this->hash . '::requestSession' ];
	}
}
?>