[UI, ADMIN] Display email ipv username (#4202)

* Displays email and username
* Shows active classes in overview

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

templates/admin/admin-classes.html

@@ -5,13 +5,15 @@
     <h1>Classes overview</h1>
     <button type="reset" class="green-btn" id="return_to_admin_page_button" onclick="window.open('/admin', '_self');">Return to admin page</button>
 </div>
-<h4 class="text-center">Total amount of shown classes: {{ classes|length }}</h4>
+<h4 class="text-center">Total amount of shown classes: {{ classes|length }} <br>
+ Total amount of active classes this week: {{ active_classes|length }}
 <div class="program w-full mx-auto border-solid border-2 border-orange-400 rounded p-4">
   <table class="table-auto w-full text-sm">
     <thead>
       <tr class="font-bold">
           <td id="classname_header">Class name</td>
           <td id="teacher_header">Teacher</td>
+          <td id="email_header">Email</td>
           <td id="created_header">Created</td>
           <td id="students_header">Students</td>
           <td id="runs_week_header">Runs this week</td>
@@ -22,11 +24,13 @@ <h4 class="text-center">Total amount of shown classes: {{ classes|length }}</h4>
           <td id="overview_header">Class overview</td>
       </tr>
     </thead>
+
     <tbody>
       {% for class in classes %}
           <tr>
             <td class="classname_cell">{{class.name}}</td>
             <td class="teacher_cell">{{class.teacher}}</td>
+            <td class="email_cell">{{class.email}}</td>
             <td class="created_cell">{{class.created}}</td>
             <td class="students_cell">{{class.students}}</td>
             <td class="runs_week_cell">{{class.stats.week.runs}}</td>

website/admin.py

@@ -131,7 +131,9 @@ def get_admin_classes_page(self, user):
         classes = [
             {
                 "name": Class.get("name"),
+                # replace email by username for easier communication
                 "teacher": Class.get("teacher"),
+                "email": self.db.user_by_username(Class.get("teacher")).get("email"),
                 "created": utils.localized_date_format(Class.get("date")),
                 "students": len(Class.get("students")) if "students" in Class else 0,
                 "stats": statistics.get_general_class_stats(Class.get("students", [])),
@@ -140,9 +142,14 @@ def get_admin_classes_page(self, user):
             for Class in self.db.all_classes()
         ]
 
+        active_classes = [x for x in classes if x.get("stats").get("week").get("runs") > 0]
+
         classes = sorted(classes, key=lambda d: d.get("stats").get("week").get("runs"), reverse=True)
 
-        return render_template("admin/admin-classes.html", classes=classes, page_title=gettext("title_admin"))
+        return render_template("admin/admin-classes.html",
+                               active_classes=active_classes,
+                               classes=classes,
+                               page_title=gettext("title_admin"))
 
     @route("/adventures", methods=["GET"])
     @requires_admin