<?php
/**
 * This is a Model for CakePHP that allows you to use the excellent Akismet
 * Api to fight spam in your application. 
 * 
 * See http://akismet.com/ for more information.
 * 
 * Licensed under The MIT License
 * Redistributions of files must retain the above copyright notice.
 * 
 * Author: Felix Geisendörfer (thinkingphp.org / fg-webdesign.de)
 **/

// If you don't have the WebModel class, go to http://cakeforge.org/snippet/detail.php?type=package&id=18
// and get it from there and putt it as web_model.php in your /app/ directory.
require_once(APP.'web_model.php');

class Akismet extends WebModel 
{
    /**
     * se of the Akismet API requires an API key, which are currently 
     * only being provided along with accounts to WordPress.com. However
     * you can sign up there for free and just take the api key for your
     * project. However, check the conditions on akismet.com
     *
     * @var string
     */
    var $apiKey = null;

    /**
     * Akismet likes to know the Application and Plugin name and version
     * it's beeing called from. So let's be nice and give it to them.
     *
     * @var string
     */
    var $userAgent = 'CakePHP/1.1 | Akismet Web Model/1.0';

    /**
     * Verfies if a given Akismet API key is valid or not.
     *
     * @param string $key Only needed when $this->apiKey isn't set
     * @param string $blog Url to your front page, get's detected automatically if ommited
     * @return string
     */
    function verifyKey($key = null, $blog = null)
    {
        $vars = array();
        
        if (empty($blog))
            $vars['blog'] = FULL_BASE_URL;
        else 
            $vars['blog'] = $blog;
            
        if (empty($key))
            $vars['key'] = $this->apiKey;
        else 
            $vars['key'] = $key;
        
        $url = 'http://rest.akismet.com/1.1/verify-key';
        
        $headers = array();
        $headers[] = 'User-Agent: '.$this->userAgent;
        
        return $this->httpPost($url, $vars, $headers);         
    }
    
    /**
     * Checks weather a given $comment array is Spam or not.
     * See http://akismet.com/development/api/#comment-check
     * for information about the available paramters.
     * 
     * Imo the most important ones are these:
     * - comment_author
     * - comment_author_email
     * - comment_author_url
     * 
     * Returns 'true' if the comment is Spam and 'false' if it isn't.
     * It might also contains a short error message in some cases.
     *
     * @param array $comment
     * @return string
     */
    function checkComment($comment)
    {
        return $this->__commentCall($comment, 'comment-check');
    }
    
    /**
     * Same parameters Akismet::checkComment(). The only difference is,
     * that it is used to report a comment as spam so Akismet can learn 
     * from it's mistakes.
     * 
     * I think Akismet returns '1' if submit was successfull and '0' if not.
     *
     * @param array $comment
     * @return string
     */
    function submitSpam($comment)
    {
        return $this->__commentCall($comment, 'submit-spam');
    }
    
    /**
     * Same parameters Akismet::checkComment(). The only difference is,
     * that it is used to report a false positive spam comment, so Akismet
     * can learn from it's mistakes.
     * 
     * I think Akismet returns '1' if submit was successfull and '0' if not.
     *
     * @param array $comment
     * @return string
     */    
    function submitHam($comment)
    {
        return $this->__commentCall($comment, 'submit-ham');
    }
    
    /**
     * Used to perform comment related Api calls.
     *
     * @param array $comment
     * @param string $type
     * @return string
     */
    function __commentCall($comment, $type = 'comment-check')
    {
        if (empty($this->apiKey))
        {
            // People will go crazy if they don't figure out they need an Api, so let's make there live
            // a little easier ; ).
            trigger_error('Akismet::checkComment() failed: No Akismet Api key has been set.', E_USER_WARNING);
            return false;
        }
        
        $vars = array();
        
        // We use the RequestHandlerComponent in order to figure out the Client-IP and Referrer
        loadComponent('RequestHandler');
        
        if (!isset($comment['blog']))
            $vars['blog'] = FULL_BASE_URL;
                              
        if (!isset($comment['user_ip']))
            $vars['user_ip'] = RequestHandlerComponent::getClientIP();
            
        if (!isset($comment['referrer ']))            
            $vars['referrer '] = RequestHandlerComponent::getReferrer();                        

        if (!isset($comment['user_agent']))
            $vars['user_agent'] = env('HTTP_USER_AGENT');
        
        $url = 'http://'.$this->apiKey.'.rest.akismet.com/1.1/'.$type;
        $vars = array_merge($vars, $comment);
        
        $headers = array();
        $headers[] = 'User-Agent: '.$this->userAgent;
                        
        return $this->httpPost($url, $vars, $headers); 
    }    
}

?>