Add message priority enum

src/ApnAdapter.php

@@ -107,12 +107,12 @@ public function adapt(ApnMessage $message, string $token): Notification
             $notification->setId($apnsId);
         }
 
-        if ($message->priority === ApnMessage::PRIORITY_HIGH) {
-            $notification->setHighPriority();
+        if ($message->priority === ApnMessagePriority::Low) {
+            $notification->setLowPriority();
         }
 
-        if ($message->priority === ApnMessage::PRIORITY_LOW) {
-            $notification->setLowPriority();
+        if ($message->priority === ApnMessagePriority::High) {
+            $notification->setHighPriority();
         }
 
         return $notification;

src/ApnMessage.php

@@ -7,9 +7,6 @@
 
 class ApnMessage
 {
-    const PRIORITY_HIGH = 10;
-    const PRIORITY_LOW = 5;
-
     /**
      * The background push type.
      *
@@ -119,9 +116,9 @@ class ApnMessage
     public ?string $apnsId = null;
 
     /**
-     * The priority of the notification. 10 - immediate. 5 - power considerations.
+     * The message priority.
      */
-    public ?int $priority = null;
+    public ?ApnMessagePriority $priority = null;
 
     /**
      * Message specific client.
@@ -290,23 +287,11 @@ public function apnsId(?string $apnsId): self
     }
 
     /**
-     * Set high priority.
-     */
-    public function setHighPriority(): self
-    {
-        $this->priority = self::PRIORITY_HIGH;
-
-        return $this;
-    }
-
-    /**
-     * Set low priority.
-     *
-     * @return Notification
+     * Set the message priority.
      */
-    public function setLowPriority(): self
+    public function priority(ApnMessagePriority $priority): self
     {
-        $this->priority = self::PRIORITY_LOW;
+        $this->priority = $priority;
 
         return $this;
     }

src/ApnMessagePriority.php

@@ -0,0 +1,9 @@
+<?php
+
+namespace NotificationChannels\Apn;
+
+enum ApnMessagePriority
+{
+    case Low;
+    case High;
+}