wip: continue implementation

src/BusProNet/Model/Availability.php

@@ -2,10 +2,18 @@
 
 namespace App\BusProNet\Model;
 
-class Availability
+class Availability implements \JsonSerializable
 {
     public ?int $serviceId = null;
     public ?string $status = null;
     public ?int $available = null;
     public ?float $price = null;
+
+    public function jsonSerialize(): array
+    {
+        return [
+            'id' => $this->serviceId,
+            'available' => $this->available,
+        ];
+    }
 }