Implicit Game Events for Game Manager

Runtime/Managers/Implementations/GameManager.cs

         [Header("Save")]
         public string ProgressSaveName = "Progress";
 
-        [Header("Messages")]
-        public string MainMenuStartMessage = "MAINMENU_START";
-        public string GameLevelStartMessage = "GAME_START";
+        public static string MainMenuStartMessage = "GAME_MANAGER_MAINMENU_START";
+        public static string GameLevelStartMessage = "GAME_MANAGER_GAME_START";
 
         public int currentLevel { get; private set; } = -2;
 
 
         Callable GetCurrentLevelSwitch(int targetLevel, bool showUI = false, Callable[] onComplete = null)
         {
+            if(targetLevel < 0 && MainMenuGameLevel == null)
+            {
+                Debug.LogError("GameManager : Could not load Main Menu.");
+                return null;
+            }
+            else if (targetLevel >= 0 && (MainGameLevels == null || MainGameLevels.Length < targetLevel + 1  || MainGameLevels[targetLevel] == null))
+            {
+                Debug.LogError($"GameManager : Could not load Level #{targetLevel}");
+                return null;
+            }
+
             GameObject go = new GameObject();
             go.name = $"LevelSwtich {currentLevel} -> {targetLevel}";
             go.transform.parent = this.transform;

Runtime/LevelScripting/Events/OnGameManagerLevelStart.cs

+using NaughtyAttributes;
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+namespace GameplayIngredients.Events
+{
+    public class OnGameManagerLevelStart : EventBase
+    {
+        public enum GameManagerLevelType
+        {
+            MainMenu,
+            GameLevel
+        }
+
+        public GameManagerLevelType levelType { get { return m_LevelType; } }
+
+        [SerializeField]
+        protected GameManagerLevelType m_LevelType = GameManagerLevelType.GameLevel;
+
+        string m_Message;
+
+        [ReorderableList]
+        public Callable[] OnMessageRecieved;
+
+        void OnEnable()
+        {
+            m_Message = GetMessage(m_LevelType);
+            Messager.RegisterMessage(m_Message, Execute);
+        }
+
+        void OnDisable()
+        {
+            Messager.RemoveMessage(m_Message, Execute);
+        }
+
+        static string GetMessage(GameManagerLevelType type)
+        {
+            switch(type)
+            {
+                case GameManagerLevelType.MainMenu:  return GameManager.MainMenuStartMessage;
+                default:
+                case GameManagerLevelType.GameLevel: return GameManager.GameLevelStartMessage;
+            }
+        }
+
+        void Execute()
+        {
+            try
+            {
+                Callable.Call(OnMessageRecieved, gameObject);
+            }
+            catch (System.Exception e)
+            {
+                UnityEngine.Debug.LogError(string.Format("OnMessageEvent : Exception Caught while catching message '{0}' on Object '{1}'", m_Message, gameObject.name));
+                UnityEngine.Debug.LogException(e);
+            }
+        }
+
+
+    }
+}
+
+

Runtime/LevelScripting/Events/OnGameManagerLevelStart.cs.meta

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