Load maxValue in KeyManager lazily

data/src/main/java/manager/KeyManagerImpl.kt

@@ -26,25 +26,28 @@ import javax.inject.Singleton
 @Singleton
 class KeyManagerImpl @Inject constructor() : KeyManager {
 
-    private var maxValue: Long = 0L
-
-    init {
-        val realm = Realm.getDefaultInstance()
-        maxValue = realm.where(Message::class.java).max("id")?.toLong() ?: 0L
-        realm.close()
-    }
+    private var initialized = false
+    private var maxValue: Long = 0
 
     /**
      * Should be called when a new sync is being started
      */
     override fun reset() {
+        initialized = true
         maxValue = 0L
     }
 
     /**
      * Returns a valid ID that can be used to store a new message
      */
     override fun newId(): Long {
+        if (!initialized) {
+            maxValue = Realm.getDefaultInstance().use { realm ->
+                realm.where(Message::class.java).max("id")?.toLong() ?: 0L
+            }
+            initialized = true
+        }
+
         maxValue++
         return maxValue
     }