如何构建智能反垃圾邮件WordPress插件

<?phpif (!function_exists('add_action')) {    die();} 
add_action('admin_menu', 'machinelearningantispam_admin_menu'); 
function machinelearningantispam_admin_menu() {
    add_submenu_page('options-general.php', __('Machine Learning Antispam'), __('Machine Learning Antispam'), 'manage_options', 'machine-learning-antispam-config', 'machinelearningantispam_conf_page');         //call register settings function
    add_action( 'admin_init', 'machinelearningantispam_settings' );} 
function machinelearningantispam_settings() {
    register_setting( 'machinelearningantispam-settings-group', 'datumbox_api_key');
    register_setting( 'machinelearningantispam-settings-group', 'machinelearningantispam_filterspam');
    register_setting( 'machinelearningantispam-settings-group', 'machinelearningantispam_filteradult');
    register_setting( 'machinelearningantispam-settings-group', 'machinelearningantispam_filternegative');} 
function machinelearningantispam_conf_page() {
        ?>    <div class="wrap">    
        <h2><?php echo __('Machine Learning Antispam'); ?></h2>     
        <?php        
        if(get_option('datumbox_api_key')=='') {    
        ?>        
        <p><b><?php 
        echo __('In order to use this plugin you must have a Datumbox API key. Sign up for a Free Datumbox Account:'); ?></b></p>        
        <button onclick="window.location='http://www.datumbox.com/users/register/';" class="button button-primary"><?php echo __('Register Now'); 
        ?></button>        
        <br/>       
        <br/>        
        <hr/><br/>    
        <?php        
        }    
        ?>         
        <form method="post" action="options.php">       
         <?php settings_fields( 'machinelearningantispam-settings-group' ); 
        ?>        
        <?php //do_settings( 'machinelearningantispam-settings-group' ); 
        ?>        
        <table class="form-table">            
        <tr valign="top">            
        <th scope="row"><?php echo __('Datumbox API Key'); ?></th>            
        <td><input type="text" name="datumbox_api_key" value="<?php echo get_option('datumbox_api_key'); ?>" /></td>            
        </tr>            <tr valign="top">           
        <th scope="row"><?php echo __('Filter Spam Comments'); ?></th>            
        <td><input type="checkbox" name="machinelearningantispam_filterspam" value="1" <?php 
        echo (get_option('machinelearningantispam_filterspam'))?'checked="checked"':''; ?> /></td>            
        </tr>            
        <tr valign="top">            
        <th scope="row"><?php echo __('Filter Adult Comments'); ?></th>            
        <td><input type="checkbox" name="machinelearningantispam_filteradult" value="1" <?php echo (get_option('machinelearningantispam_filteradult'))?'checked="checked"':''; ?> /></td>            
        </tr>            
        <tr valign="top">            
        <th scope="row"><?php echo __('Filter Negative Comments'); ?></th>            
        <td><input type="checkbox" name="machinelearningantispam_filternegative" value="1" <?php echo (get_option('machinelearningantispam_filternegative'))?'checked="checked"':''; ?> /></td>            
        </tr>        
        </table>                 
        <?php submit_button(); ?>    
        </form>    
        </div>   
<?php } ?>

<?php
/**
* Plugin Name: Machine Learning Antispam
* Plugin URI: http://www.datumbox.com
* Description: This WordPress Plugin uses Machine Learning to detect spam and adult content comments and mark them as spam. Additionally it allows you to filter negative comments and keep them pending for approval.
* Version: 1.0
* Author: Vasilis Vryniotis
* Author URI: http://www.datumbox.com
* License: GPL2
*/
if (!function_exists('add_action')) {
   die(); //block direct web requests
}
require_once(dirname( __FILE__ ).'/DatumboxAPI.php'); //require the DatumboxAPI client to easily call Datumbox 
APIif (is_admin()) { //if admin include the admin specific 
functionsrequire_once(dirname( __FILE__ ).'/options.php');}
function machinelearningantispam_get_key() {
   return get_option('datumbox_api_key'); //return the api key of datumbox}
function machinelearningantispam_call_datumbox($commentText,$type_of_check) {
   $apiKey=machinelearningantispam_get_key(); //fetch the API key
   if($apiKey==false || $apiKey=='') {
       return true; //don't block the comment if the plugin is not well configured}
   $DatumboxAPI = new DatumboxAPI($apiKey); //initialize DatumboxAPI Client
   if($type_of_check=='spam') {
       $response=$DatumboxAPI->SpamDetection($commentText); //Call Spam Detection service
       if($response=='spam') { //if spam return false 
       return false;}}
   else if($type_of_check=='adult') {
       $response=$DatumboxAPI->AdultContentDetection($commentText); //Call Adult Content Detection service
       if($response=='adult') { //if adult return false
       return false;}}
   else if($type_of_check=='negative') {
       $response=$DatumboxAPI->SentimentAnalysis($commentText); //Call Sentiment Analysis service
       if($response=='negative') { //if negative return false
       return false;}}
   unset($DatumboxAPI);
   return true;}
function machinelearningantispam_check_comment($commentdata) {
   if(get_option('machinelearningantispam_filterspam') && machinelearningantispam_call_datumbox($commentdata['comment_content'],'spam')==false) {//if Spam filtering is on and the Datumbox Service considers it spam then mark it as spam
   add_filter('pre_comment_approved', 'machinelearningantispam_result_spam');}
   else if(get_option('machinelearningantispam_filteradult') && machinelearningantispam_call_datumbox($commentdata['comment_content'],'adult')==false) {//if Adult filtering is on and the Datumbox Service considers it adult then mark it as spam
   add_filter('pre_comment_approved', 'machinelearningantispam_result_spam');}
   else if(get_option('machinelearningantispam_filternegative') && machinelearningantispam_call_datumbox($commentdata['comment_content'],'negative')==false) {//if Negative filtering is on and the Datumbox Service considers it negative then mark it as pending
   add_filter('pre_comment_approved', 'machinelearningantispam_result_pending');}
   return $commentdata;}
function machinelearningantispam_result_spam() {
   return 'spam';}
function machinelearningantispam_result_pending() {
   return 0;}
add_action( 'preprocess_comment' , 'machinelearningantispam_check_comment' );
?>