<?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_Service

 * @subpackage ReCaptcha

 * @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_Service_ReCaptcha */

require_once 'Zend/Service/ReCaptcha.php';

/**

 * Zend_Service_ReCaptcha_MailHide

 *

 * @category   Zend

 * @package    Zend_Service

 * @subpackage ReCaptcha

 * @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: MailHide.php 20108 2010-01-06 22:05:31Z matthew $

 */

class Zend_Service_ReCaptcha_MailHide extends Zend_Service_ReCaptcha

{

    /**#@+

     * Encryption constants

     */

    const ENCRYPTION_MODE = MCRYPT_MODE_CBC;

    const ENCRYPTION_CIPHER = MCRYPT_RIJNDAEL_128;

    const ENCRYPTION_BLOCK_SIZE = 16;

    const ENCRYPTION_IV = "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0";

    /**#@-*/

    /**

     * Url to the mailhide server

     *

     * @var string

     */

    const MAILHIDE_SERVER = 'http://mailhide.recaptcha.net/d';

    /**

     * The email address to protect

     *

     * @var string

     */

    protected $_email = null;

    /**

     * @var Zend_Validate_Interface

     */

    protected $_emailValidator;

    /**

     * Binary representation of the private key

     *

     * @var string

     */

    protected $_privateKeyPacked = null;

    /**

     * The local part of the email

     *

     * @var string

     */

    protected $_emailLocalPart = null;

    /**

     * The domain part of the email

     *

     * @var string

     */

    protected $_emailDomainPart = null;

    /**

     * Local constructor

     *

     * @param string $publicKey

     * @param string $privateKey

     * @param string $email

     * @param array|Zend_Config $options

     */

    public function __construct($publicKey = null, $privateKey = null, $email = null, $options = null)

    {

        /* Require the mcrypt extension to be loaded */

        $this->_requireMcrypt();

        /* If options is a Zend_Config object we want to convert it to an array so we can merge it with the default options */

        if ($options instanceof Zend_Config) {

            $options = $options->toArray();

        }

        /* Merge if needed */

        if (is_array($options)) {

            $options = array_merge($this->getDefaultOptions(), $options);

        } else {

            $options = $this->getDefaultOptions();

        }

        parent::__construct($publicKey, $privateKey, null, $options);

        if ($email !== null) {

            $this->setEmail($email);

        }

    }

    /**

     * Get emailValidator

     *

     * @return Zend_Validate_Interface

     */

    public function getEmailValidator()

    {

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

            require_once 'Zend/Validate/EmailAddress.php';

            $this->setEmailValidator(new Zend_Validate_EmailAddress());

        }

        return $this->_emailValidator;

    }

    /**

     * Set email validator

     *

     * @param  Zend_Validate_Interface $validator

     * @return Zend_Service_ReCaptcha_MailHide

     */

    public function setEmailValidator(Zend_Validate_Interface $validator)

    {

        $this->_emailValidator = $validator;

        return $this;

    }

    /**

     * See if the mcrypt extension is available

     *

     * @throws Zend_Service_ReCaptcha_MailHide_Exception

     */

    protected function _requireMcrypt()

    {

        if (!extension_loaded('mcrypt')) {

            /** @see Zend_Service_ReCaptcha_MailHide_Exception */

            require_once 'Zend/Service/ReCaptcha/MailHide/Exception.php';

            throw new Zend_Service_ReCaptcha_MailHide_Exception('Use of the Zend_Service_ReCaptcha_MailHide component requires the mcrypt extension to be enabled in PHP');

        }

    }

    /**

     * Serialize as string

     *

     * When the instance is used as a string it will display the email address. Since we can't

     * throw exceptions within this method we will trigger a user warning instead.

     *

     * @return string

     */

    public function __toString()

    {

        try {

            $return = $this->getHtml();

        } catch (Exception $e) {

            $return = '';

            trigger_error($e->getMessage(), E_USER_WARNING);

        }

        return $return;

    }

    /**

     * Get the default set of parameters

     *

     * @return array

     */

    public function getDefaultOptions()

    {

        return array(

            'encoding'       => 'UTF-8',

            'linkTitle'      => 'Reveal this e-mail address',

            'linkHiddenText' => '...',

            'popupWidth'     => 500,

            'popupHeight'    => 300,

        );

    }

    /**

     * Override the setPrivateKey method

     *

     * Override the parent method to store a binary representation of the private key as well.

     *

     * @param string $privateKey

     * @return Zend_Service_ReCaptcha_MailHide

     */

    public function setPrivateKey($privateKey)

    {

        parent::setPrivateKey($privateKey);

        /* Pack the private key into a binary string */

        $this->_privateKeyPacked = pack('H*', $this->_privateKey);

        return $this;

    }

    /**

     * Set the email property

     *

     * This method will set the email property along with the local and domain parts

     *

     * @param string $email

     * @return Zend_Service_ReCaptcha_MailHide

     */

    public function setEmail($email)

    {

        $this->_email = $email;

        $validator = $this->getEmailValidator();

        if (!$validator->isValid($email)) {

            require_once 'Zend/Service/ReCaptcha/MailHide/Exception.php';

            throw new Zend_Service_ReCaptcha_MailHide_Exception('Invalid email address provided');

        }

        $emailParts = explode('@', $email, 2);

        /* Decide on how much of the local part we want to reveal */

        if (strlen($emailParts[0]) <= 4) {

            $emailParts[0] = substr($emailParts[0], 0, 1);

        } else if (strlen($emailParts[0]) <= 6) {

            $emailParts[0] = substr($emailParts[0], 0, 3);

        } else {

            $emailParts[0] = substr($emailParts[0], 0, 4);

        }

        $this->_emailLocalPart = $emailParts[0];

        $this->_emailDomainPart = $emailParts[1];

        return $this;

    }

    /**

     * Get the email property

     *

     * @return string

     */

    public function getEmail()

    {

        return $this->_email;

    }

    /**

     * Get the local part of the email address

     *

     * @return string

     */

    public function getEmailLocalPart()

    {

        return $this->_emailLocalPart;

    }

    /**

     * Get the domain part of the email address

     *

     * @return string

     */

    public function getEmailDomainPart()

    {

        return $this->_emailDomainPart;

    }

    /**

     * Get the HTML code needed for the mail hide

     *

     * @param string $email

     * @return string

     * @throws Zend_Service_ReCaptcha_MailHide_Exception

     */

    public function getHtml($email = null)

    {

        if ($email !== null) {

            $this->setEmail($email);

        } elseif (null === ($email = $this->getEmail())) {

            /** @see Zend_Service_ReCaptcha_MailHide_Exception */

            require_once 'Zend/Service/ReCaptcha/MailHide/Exception.php';

            throw new Zend_Service_ReCaptcha_MailHide_Exception('Missing email address');

        }

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

            /** @see Zend_Service_ReCaptcha_MailHide_Exception */

            require_once 'Zend/Service/ReCaptcha/MailHide/Exception.php';

            throw new Zend_Service_ReCaptcha_MailHide_Exception('Missing public key');

        }

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

            /** @see Zend_Service_ReCaptcha_MailHide_Exception */

            require_once 'Zend/Service/ReCaptcha/MailHide/Exception.php';

            throw new Zend_Service_ReCaptcha_MailHide_Exception('Missing private key');

        }

        /* Generate the url */

        $url = $this->_getUrl();

        $enc = $this->getOption('encoding');

        /* Genrate the HTML used to represent the email address */

        $html = htmlentities($this->getEmailLocalPart(), ENT_COMPAT, $enc) 

            . '<a href="' 

                . htmlentities($url, ENT_COMPAT, $enc) 

                . '" onclick="window.open(\'' 

                    . htmlentities($url, ENT_COMPAT, $enc) 

                    . '\', \'\', \'toolbar=0,scrollbars=0,location=0,statusbar=0,menubar=0,resizable=0,width='

                    . $this->_options['popupWidth'] 

                    . ',height=' 

                    . $this->_options['popupHeight'] 

                . '\'); return false;" title="' 

                . $this->_options['linkTitle'] 

                . '">' . $this->_options['linkHiddenText'] . '</a>@' 

                . htmlentities($this->getEmailDomainPart(), ENT_COMPAT, $enc);

        return $html;

    }

    /**

     * Get the url used on the "hidden" part of the email address

     *

     * @return string

     */

    protected function _getUrl()

    {

        /* Figure out how much we need to pad the email */

        $numPad = self::ENCRYPTION_BLOCK_SIZE - (strlen($this->_email) % self::ENCRYPTION_BLOCK_SIZE);

        /* Pad the email */

        $emailPadded = str_pad($this->_email, strlen($this->_email) + $numPad, chr($numPad));

        /* Encrypt the email */

        $emailEncrypted = mcrypt_encrypt(self::ENCRYPTION_CIPHER, $this->_privateKeyPacked, $emailPadded, self::ENCRYPTION_MODE, self::ENCRYPTION_IV);

        /* Return the url */

        return self::MAILHIDE_SERVER . '?k=' . $this->_publicKey . '&c=' . strtr(base64_encode($emailEncrypted), '+/', '-_');

    }

}