fix slug

src/Entity/Entity.php

@@ -4,9 +4,13 @@ namespace Bluesquare\Pilot\Entity;
 
 abstract class Entity
 {
-    public function __construct(protected $slug = null)
-    {
+    protected $slug = null;
 
+    public function __construct($slug = null)
+    {
+        if (! is_null($slug)) {
+            $this->slug = $slug;
+        }
     }
 
     public function slug()

src/Entity/Metric.php

@@ -48,7 +48,7 @@ abstract class Metric extends Widget
     {
         $filter = collect($filters)->firstWhere('value', $this->data['filter'] ?? null) ?? collect($filters)->first();
 
-        $computed = is_array($filter) ? $filter['callback']($this->data) : [];
+        $computed = is_array($filter) ? $filter['callback']() : [];
 
         return [
             'filter' => $filter['value'],
@@ -74,19 +74,18 @@ abstract class Metric extends Widget
 
     public function progress($current, $target)
     {
-        return $this->output([
+        return [
             'type' => 'progress',
             'value' => $current,
             'target' => $target,
-        ]);
+        ];
     }
 
-    public function trend($value, $previous = null)
+    public function trend($values)
     {
         return [
             'type' => 'trend',
-            'value' => $value,
-            'previous' => $previous,
+            'values' => $values,
         ];
     }
 
@@ -98,11 +97,12 @@ abstract class Metric extends Widget
         ];
     }
 
-    public function value($value)
+    public function value($value, $previous = null)
     {
         return [
             'type' => 'value',
             'value' => $value,
+            'previous' => $previous,
         ];
     }