allow embedding of single files; closes #1

filter.php

@@ -1,17 +1,15 @@
 <?php
 
 class filter_gistembed extends moodle_text_filter {
-    
-    public function filter($text, array $options = array()) { 
-        $cnt = preg_match_all('/https?:\/\/gist\.github\.com\/(.*?)\/([a-f0-9]*)/', $text, $matches);
-        if ($cnt) {
-            for ($i=0; $i<$cnt; ++$i) {
-                $script = '<script src="https://gist.github.com/' . $matches[1][$i] . '/' . $matches[2][$i] . '.js"></script>'; 
-                 $text = str_replace($matches[0][$i], $script, $text); 
+
+    public function filter( $text, array $options = [ ] ) {
+        return preg_replace_callback( '/https?:\/\/gist\.github\.com\/(.*?)\/([a-f0-9]*)(\?file=[^\s<>]*)?/', function($matches) {
+            //echo '<pre>' . print_r($matches, true) . '</pre>';
+            $src = 'https://gist.github.com/' . $matches[1] . '/' . $matches[2] . '.js';
+            if (!empty($matches[3])) {
+                $src .= $matches[3];
             }
-        }
-        return $text; 
+            return '<script src="' . $src . '"></script>';
+        }, $text );
     }
-
 }
-

readme.md

@@ -102,6 +102,12 @@ Forum button. You should see something like this.
 
 And that's it. You're all set. 
 
+#### Embedding single files
+If you're embedding a gist with multiple files, normally all files will embed. If you'd rather
+embed only a single file add `?file=Filename.ext` to the end of the URL that you paste into
+Moodle and only that file will embed. If that file doesn't exist in your gist nothing
+will embed. 
+
 ### Settings
 
 There really aren't any. Just paste in the link.

version.php

@@ -2,9 +2,9 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-$plugin->version = '2015092400';
+$plugin->version = '2017102100';
 $plugin->requires = '2014051200'; // 2.7
 $plugin->cron = 0;
 $plugin->component = 'filter_gistembed';
 $plugin->maturity = MATURITY_BETA;
-$plugin->release = '0.1';
+$plugin->release = '0.2';