Sort the pages in a lesson from the `level` parameter.

user/plugins/m3-p2/m3-p2.php

@@ -239,7 +239,6 @@ class M3P2Plugin extends Plugin
         }
 
         $lesson_slug = $uri->paths(1);
-//        var_dump($lesson_slug);
 
 //        $target_pages = $pages->all()->filter(function ($p) use ($lesson_slug) {
         $target_pages = array_filter($pages->instances(), function (Page $p) use ($lesson_slug) {
@@ -258,11 +257,30 @@ class M3P2Plugin extends Plugin
             return false;
         });
 
-//        var_dump($target_pages);
+        usort($target_pages, function (Page $a, Page $b) use ($lesson_slug) {
+            $la = 0;
+            $lb = 0;
 
-        // fixme: sort pages
+            $ha = $a->header();
+            $hb = $b->header();
 
-//        $target_page = $pages->all();
+            $fdp = function ($pp) use ($lesson_slug) {
+                return $pp["slug"] == $lesson_slug;
+            };
+
+            // We're assuming the config exists (it should)
+            $ma = array_filter($ha->pedagogic_paths, $fdp)[0];
+            $mb = array_filter($hb->pedagogic_paths, $fdp)[0];
+
+            if (isset($ma['level'])) {
+                $la = floor($ma['level']);
+            }
+            if (isset($mb['level'])) {
+                $lb = floor($mb['level']);
+            }
+
+            return $la - $lb;
+        });
 
         if (empty($target_pages)) {
             return;