Add confirmation dialog when deleting all alerts

www/docs/js/main.js

@@ -487,6 +487,23 @@ document.addEventListener('DOMContentLoaded', function() {
 });
 
 
+// Confirm Alert deletion
+function confirm_delete_handler(event) {
+  event.preventDefault();
+  if (confirm('Are you sure you want to delete all alerts?')) {
+    event.target.closest('form').submit();
+  }
+}
+
+function setup_confirm_delete() {
+  document.querySelectorAll('.js-confirm-delete').forEach(function(button) {
+    button.addEventListener('click', confirm_delete_handler);
+  });
+}
+
+document.addEventListener('DOMContentLoaded', setup_confirm_delete);
+
+
 $(function() {
 
   $('#how-often-annually').click(function() {

www/includes/easyparliament/templates/html/alert/_list.php

@@ -10,6 +10,6 @@
 <div class="clearfix">
     <form action="<?= $actionurl ?>" method="POST" class="pull-right">
         <!-- No need to reference $alert['token'] here, as you're deleting all alerts -->
-        <input type="submit" class="button button--negative small" name="action" value="<?= gettext('Delete All') ?>">
+        <input type="submit" class="button button--negative small js-confirm-delete" name="action" value="<?= gettext('Delete all alerts') ?>">
     </form>
 </div>

www/includes/easyparliament/templates/html/alert/index.php

@@ -316,7 +316,7 @@
                 <?php if ($keyword_alerts || $spoken_alerts || $own_member_alerts) { ?>
                   <form action="<?= $actionurl ?>" method="POST" class="pull-right">
                       <input type="hidden" name="t" value="<?= _htmlspecialchars($delete_token) ?>">
-                      <input type="submit" class="button button--negative small" name="action" value="<?= gettext('Delete All') ?>">
+                      <input type="submit" class="button button--negative small js-confirm-delete" name="action" value="<?= gettext('Delete all alerts') ?>">
                   </form>
                 <?php } ?>
                   <form action="<?= $actionurl ?>" method="post">