Add machine folder validation

Author: arthurkehrwald

Editor/Inspector/MpfGamelogicEngineInspector.cs

@@ -68,7 +68,7 @@ public override VisualElement CreateInspectorGUI()
                             path = "./StreamingAssets/" + path.Split("StreamingAssets/")[1];
 
                         var machineFolderProp = serializedObject.FindProperty(
-                            $"_mpfStarter._machineFolder"
+                            $"_mpfWrangler._machineFolder"
                         );
                         machineFolderProp.stringValue = path;
                         serializedObject.ApplyModifiedProperties();
@@ -195,6 +195,9 @@ ex is RpcException exception
                 executableSourceProp,
                 OnExecutableSourceChanged
             );
+
+            MachineFolderValidationBoxes(machineFolderField);
+
             return root;
         }
 
@@ -255,5 +258,44 @@ private void UpdateGameItemList(VisualElement parent, IEnumerable<string> itemId
                 parent.Add(label);
             }
         }
+
+        private void MachineFolderValidationBoxes(VisualElement machineFolderField)
+        {
+            var machineFolderProp = serializedObject.FindProperty($"_mpfWrangler._machineFolder");
+            var notAMachineFolderErrorBox = new HelpBox(
+                "The machine folder is not valid. It must contain a folder called 'config' "
+                    + "with at least one .yaml file inside.",
+                HelpBoxMessageType.Error
+            );
+            var streamingAssetsWarnBox = new HelpBox(
+                "The machine folder is not located in the 'StreamingAssets' folder. It will not be"
+                    + " included in builds.",
+                HelpBoxMessageType.Warning
+            );
+            streamingAssetsWarnBox.TrackPropertyValue(machineFolderProp, UpdateVisibility);
+            var container = machineFolderField.parent;
+            var index = container.IndexOf(machineFolderField);
+            container.Insert(index, notAMachineFolderErrorBox);
+            container.Insert(index + 1, streamingAssetsWarnBox);
+            UpdateVisibility(machineFolderProp);
+
+            void UpdateVisibility(SerializedProperty _)
+            {
+                var machineFolder = _mpfEngine.MachineFolder;
+                var isMachineFolderInStreamingAssets = machineFolder.StartsWith(
+                    Application.streamingAssetsPath
+                );
+                streamingAssetsWarnBox.style.display = isMachineFolderInStreamingAssets
+                    ? DisplayStyle.None
+                    : DisplayStyle.Flex;
+
+                var configDir = Path.Combine(machineFolder, "config");
+                var isValidMachineFolder =
+                    Directory.Exists(configDir) && Directory.GetFiles(configDir, "*.yaml").Any();
+                notAMachineFolderErrorBox.style.display = isValidMachineFolder
+                    ? DisplayStyle.None
+                    : DisplayStyle.Flex;
+            }
+        }
     }
 }

Runtime/MpfGamelogicEngine.cs

@@ -81,6 +81,8 @@ public class MpfGamelogicEngine : MonoBehaviour, IGamelogicEngine
         public event EventHandler<SwitchEventArgs2> OnSwitchChanged;
 #pragma warning restore CS0067
 
+        public string MachineFolder => _mpfWrangler.MachineFolder;
+
 #if UNITY_EDITOR
         public async Task QueryParseAndStoreMpfMachineDescription(CancellationToken ct)
         {