list/servicegrid: Add toggle to show problems only or everything

resolves #3793

modules/monitoring/application/controllers/ListController.php

@@ -3,6 +3,7 @@
 
 namespace Icinga\Module\Monitoring\Controllers;
 
+use Icinga\Web\Form;
 use Zend_Form;
 use Icinga\Data\Filter\Filter;
 use Icinga\Module\Monitoring\Backend;
@@ -669,6 +670,19 @@ class ListController extends Controller
         $this->applyRestriction('monitoring/filter/objects', $query);
         $this->filterQuery($query);
         $filter = (bool) $this->params->shift('problems', false) ? Filter::where('service_problem', 1) : null;
+
+        $this->view->problemToggle = $problemToggle = new Form(['method' => 'GET']);
+        $problemToggle->setUidDisabled();
+        $problemToggle->setTokenDisabled();
+        $problemToggle->setAttrib('class', 'filter-toggle inline icinga-controls');
+        $problemToggle->addElement('checkbox', 'problems', [
+            'disableHidden' => true,
+            'autosubmit'    => true,
+            'value'         => $filter !== null,
+            'label'         => $this->translate('Problems Only'),
+            'decorators'    => ['ViewHelper', ['Label', ['placement' => 'APPEND']]]
+        ]);
+
         if ($this->params->get('flipped', false)) {
             $pivot = $query
                 ->pivot(

modules/monitoring/application/views/scripts/list/servicegrid.phtml

@@ -6,6 +6,7 @@ use Icinga\Web\Url;
 if (! $this->compact): ?>
 <div class="controls">
     <?= $this->tabs ?>
+    <?= $this->problemToggle ?>
     <div class="sort-controls-container">
         <?= $this->sortBox ?>
     </div>

modules/monitoring/public/css/service-grid.less

@@ -60,3 +60,16 @@
   vertical-align: middle;
   width: 1.5em;
 }
+
+form.filter-toggle {
+  label:not(.toggle-switch) {
+    display: inline-block;
+    vertical-align: top;
+    margin-left: .5em;
+    color: @gray-light;
+  }
+
+  input[type="checkbox"]:checked ~ label {
+    color: inherit;
+  }
+}