<?php

/**

 * Zend Framework

 *

 * LICENSE

 *

 * This source file is subject to the new BSD license that is bundled

 * with this package in the file LICENSE.txt.

 * It is also available through the world-wide-web at this URL:

 * http://framework.zend.com/license/new-bsd

 * If you did not receive a copy of the license and are unable to

 * obtain it through the world-wide-web, please send an email

 * to license@zend.com so we can send you a copy immediately.

 *

 * @category   Zend

 * @package    Zend_Captcha

 * @subpackage Adapter

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 */

/** @see Zend_Captcha_Base */

require_once 'Zend/Captcha/Base.php';

/**

 * Word-based captcha adapter

 *

 * Generates random word which user should recognise

 *

 * @category   Zend

 * @package    Zend_Captcha

 * @subpackage Adapter

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 * @version    $Id: Word.php 21793 2010-04-08 00:51:31Z stas $

 */

abstract class Zend_Captcha_Word extends Zend_Captcha_Base

{

    /**#@+

     * @var array Character sets

     */

    static $V  = array("a", "e", "i", "o", "u", "y");

    static $VN = array("a", "e", "i", "o", "u", "y","2","3","4","5","6","7","8","9");

    static $C  = array("b","c","d","f","g","h","j","k","m","n","p","q","r","s","t","u","v","w","x","z");

    static $CN = array("b","c","d","f","g","h","j","k","m","n","p","q","r","s","t","u","v","w","x","z","2","3","4","5","6","7","8","9");

    /**#@-*/

    /**

     * Random session ID

     *

     * @var string

     */

    protected $_id;

    /**

     * Generated word

     *

     * @var string

     */

    protected $_word;

    /**

     * Session

     *

     * @var Zend_Session_Namespace

     */

    protected $_session;

    /**

     * Class name for sessions

     *

     * @var string

     */

    protected $_sessionClass = 'Zend_Session_Namespace';

    /**

     * Should the numbers be used or only letters

     *

     * @var boolean

     */

    protected $_useNumbers = true;

    /**

     * Should both cases be used or only lowercase

     *

     * @var boolean

     */

    // protected $_useCase = false;

    /**

     * Session lifetime for the captcha data

     *

     * @var integer

     */

    protected $_timeout = 300;

    /**

     * Should generate() keep session or create a new one?

     * 

     * @var boolean

     */

    protected $_keepSession = false;

    /**#@+

     * Error codes

     */

    const MISSING_VALUE = 'missingValue';

    const MISSING_ID    = 'missingID';

    const BAD_CAPTCHA   = 'badCaptcha';

    /**#@-*/

    /**

     * Error messages

     * @var array

     */

    protected $_messageTemplates = array(

        self::MISSING_VALUE => 'Empty captcha value',

        self::MISSING_ID    => 'Captcha ID field is missing',

        self::BAD_CAPTCHA   => 'Captcha value is wrong',

    );

    /**

     * Length of the word to generate

     *

     * @var integer

     */

    protected $_wordlen = 8;

    /**

     * Retrieve session class to utilize

     *

     * @return string

     */

	public function getSessionClass()

    {

        return $this->_sessionClass;

    }

    /**

     * Set session class for persistence

     *

     * @param  string $_sessionClass

     * @return Zend_Captcha_Word

     */

    public function setSessionClass($_sessionClass)

    {

        $this->_sessionClass = $_sessionClass;

        return $this;

    }

    /**

     * Retrieve word length to use when genrating captcha

     *

     * @return integer

     */

    public function getWordlen()

    {

        return $this->_wordlen;

    }

    /**

     * Set word length of captcha

     *

     * @param integer $wordlen

     * @return Zend_Captcha_Word

     */

    public function setWordlen($wordlen)

    {

        $this->_wordlen = $wordlen;

        return $this;

    }

    /**

     * Retrieve captcha ID

     *

     * @return string

     */

    public function getId ()

    {

        if (null === $this->_id) {

            $this->_setId($this->_generateRandomId());

        }

        return $this->_id;

    }

    /**

     * Set captcha identifier

     *

     * @param string $id

     * return Zend_Captcha_Word

     */

    protected function _setId ($id)

    {

        $this->_id = $id;

        return $this;

    }

    /**

     * Set timeout for session token

     *

     * @param  int $ttl

     * @return Zend_Captcha_Word

     */

    public function setTimeout($ttl)

    {

        $this->_timeout = (int) $ttl;

        return $this;

    }

    /**

     * Get session token timeout

     *

     * @return int

     */

    public function getTimeout()

    {

        return $this->_timeout;

    }

	/**

	 * Sets if session should be preserved on generate()

	 * 

	 * @param $keepSession Should session be kept on generate()?

	 * @return Zend_Captcha_Word

	 */

	public function setKeepSession($keepSession) 

	{

		$this->_keepSession = $keepSession;

		return $this;

	}

    /**

     * Numbers should be included in the pattern?

     * 

     * @return bool

     */

    public function getUseNumbers()

    {

        return $this->_useNumbers;

    }

	/**

	 * Set if numbers should be included in the pattern

	 * 

     * @param $_useNumbers numbers should be included in the pattern?

     * @return Zend_Captcha_Word

     */

    public function setUseNumbers($_useNumbers)

    {

        $this->_useNumbers = $_useNumbers;

        return $this;

    }

	/**

     * Get session object

     *

     * @return Zend_Session_Namespace

     */

    public function getSession()

    {

        if (!isset($this->_session) || (null === $this->_session)) {

            $id = $this->getId();

            if (!class_exists($this->_sessionClass)) {

                require_once 'Zend/Loader.php';

                Zend_Loader::loadClass($this->_sessionClass);

            }

            $this->_session = new $this->_sessionClass('Zend_Form_Captcha_' . $id);

            $this->_session->setExpirationHops(1, null, true);

            $this->_session->setExpirationSeconds($this->getTimeout());

        }

        return $this->_session;

    }

    /**

     * Set session namespace object

     *

     * @param  Zend_Session_Namespace $session

     * @return Zend_Captcha_Word

     */

    public function setSession(Zend_Session_Namespace $session)

    {

        $this->_session = $session;

        if($session) {

            $this->_keepSession = true;

        }

        return $this;

    }

    /**

     * Get captcha word

     *

     * @return string

     */

    public function getWord()

    {

        if (empty($this->_word)) {

            $session     = $this->getSession();

            $this->_word = $session->word;

        }

        return $this->_word;

    }

    /**

     * Set captcha word

     *

     * @param  string $word

     * @return Zend_Captcha_Word

     */

    protected function _setWord($word)

    {

        $session       = $this->getSession();

        $session->word = $word;

        $this->_word   = $word;

        return $this;

    }

    /**

     * Generate new random word

     *

     * @return string

     */

    protected function _generateWord()

    {

        $word       = '';

        $wordLen    = $this->getWordLen();

        $vowels     = $this->_useNumbers ? self::$VN : self::$V;

        $consonants = $this->_useNumbers ? self::$CN : self::$C;

        for ($i=0; $i < $wordLen; $i = $i + 2) {

            // generate word with mix of vowels and consonants

            $consonant = $consonants[array_rand($consonants)];

            $vowel     = $vowels[array_rand($vowels)];

            $word     .= $consonant . $vowel;

        }

        if (strlen($word) > $wordLen) {

            $word = substr($word, 0, $wordLen);

        }

        return $word;

    }

    /**

     * Generate new session ID and new word

     *

     * @return string session ID

     */

    public function generate()

    {

        if(!$this->_keepSession) {

            $this->_session = null;   

        }

        $id = $this->_generateRandomId();

        $this->_setId($id);

        $word = $this->_generateWord();

        $this->_setWord($word);

        return $id;

    }

    protected function _generateRandomId()

    {

        return md5(mt_rand(0, 1000) . microtime(true));

    }

    /**

     * Validate the word

     *

     * @see    Zend_Validate_Interface::isValid()

     * @param  mixed $value

     * @return boolean

     */

    public function isValid($value, $context = null)

    {

        if (!is_array($value) && !is_array($context)) {

            $this->_error(self::MISSING_VALUE);

            return false;

        }

        if (!is_array($value) && is_array($context)) {

            $value = $context;

        }

        $name = $this->getName();

        if (isset($value[$name])) {

            $value = $value[$name];

        }

        if (!isset($value['input'])) {

            $this->_error(self::MISSING_VALUE);

            return false;

        }

        $input = strtolower($value['input']);

        $this->_setValue($input);

        if (!isset($value['id'])) {

            $this->_error(self::MISSING_ID);

            return false;

        }

        $this->_id = $value['id'];

        if ($input !== $this->getWord()) {

            $this->_error(self::BAD_CAPTCHA);

            return false;

        }

        return true;

    }

    /**

     * Get captcha decorator

     *

     * @return string

     */

    public function getDecorator()

    {

        return "Captcha_Word";

    }

}