Allow spam score threshold to be passed for each form rather than defined on the page

Signed-off-by: Richard Mansfield <richardm@catalyst.net.nz>

htdocs/contact.php

@@ -34,7 +34,6 @@ require('init.php');
 require_once('pieforms/pieform.php');
 require_once('lib/antispam.php');
 define('TITLE', get_string('contactus'));
-define('SPAM_SCORE', 3);
 
 if ($USER->is_logged_in()) {
     $userid = $USER->get('id');

htdocs/lib/antispam/NoneSpamTrap.php

@@ -37,9 +37,9 @@ class NoneSpamTrap {
         $this->fields = $fields;
     }
 
-    public function is_spam() {
+    public function is_spam($threshold=3) {
         // if no spam score threshold is defined, never call something spam
-        if (!defined('SPAM_SCORE')) {
+        if (empty($threshold)) {
             return false;
         }
         $score = 0;
@@ -49,7 +49,7 @@ class NoneSpamTrap {
                 $score += $this->$method($field['value']);
             }
         }
-        if ($score > SPAM_SCORE) {
+        if ($score > $threshold) {
             return true;
         }
         return false;

htdocs/register.php

@@ -34,7 +34,6 @@ require('init.php');
 require_once('pieforms/pieform.php');
 require_once('lib/antispam.php');
 define('TITLE', get_string('register'));
-define('SPAM_SCORE', 3);
 $key = param_alphanum('key', null);
 
 /*