Event conditions - Fix start-node disconnecting

Input - Performance optimizations

src/Artemis.VisualScripting/Nodes/List/ListOperatorPredicateNode.cs

@@ -9,10 +9,11 @@ namespace Artemis.VisualScripting.Nodes.List;
 public class ListOperatorPredicateNode : Node<ListOperatorEntity, ListOperatorPredicateNodeCustomViewModel>, IDisposable
 {
     private readonly object _scriptLock = new();
-    private ListOperatorPredicateStartNode? _startNode;
+    private ListOperatorPredicateStartNode _startNode;
 
     public ListOperatorPredicateNode() : base("List Operator (Advanced)", "Checks if any/all/no values in the input list match a condition")
     {
+        _startNode = new ListOperatorPredicateStartNode {X = -200};
 
         InputList = CreateInputPin<IList>();
         Output = CreateOutputPin<bool>();
@@ -31,21 +32,8 @@ public class ListOperatorPredicateNode : Node<ListOperatorEntity, ListOperatorPr
         lock (_scriptLock)
         {
             Script = Storage?.Script != null
-                ? new NodeScript<bool>("Is match", "Determines whether the current list item is a match", Storage.Script, script.Context)
-                : new NodeScript<bool>("Is match", "Determines whether the current list item is a match", script.Context);
-
-            // The load action may have created an event node, use that one over the one we have here
-            INode? existingEventNode = Script.Nodes.FirstOrDefault(n => n.Id == ListOperatorPredicateStartNode.NodeId);
-            if (existingEventNode != null)
-                _startNode = (ListOperatorPredicateStartNode) existingEventNode;
-            else
-            {
-                _startNode = new ListOperatorPredicateStartNode {X = -200};
-                Script.AddNode(_startNode);
-            }
-
-            UpdateStartNode();
-            Script.LoadConnections();
+                ? new NodeScript<bool>("Is match", "Determines whether the current list item is a match", Storage.Script, script.Context, new List<DefaultNode> {_startNode})
+                : new NodeScript<bool>("Is match", "Determines whether the current list item is a match", script.Context, new List<DefaultNode> {_startNode});
         }
     }
 
@@ -101,6 +89,7 @@ public class ListOperatorPredicateNode : Node<ListOperatorEntity, ListOperatorPr
         lock (_scriptLock)
         {
             UpdateStartNode();
+            Script?.LoadConnections();
         }
     }
 

src/Artemis.VisualScripting/Nodes/List/Screens/ListOperatorPredicateNodeCustomViewModel.cs

@@ -1,5 +1,7 @@
 using System.Reactive;
+using System.Reactive.Disposables;
 using Artemis.Core;
+using Artemis.Core.Events;
 using Artemis.UI.Shared.Services;
 using Artemis.UI.Shared.Services.NodeEditor;
 using Artemis.UI.Shared.VisualScripting;
@@ -12,17 +14,37 @@ public class ListOperatorPredicateNodeCustomViewModel : CustomNodeViewModel
     private readonly ListOperatorPredicateNode _node;
     private readonly IWindowService _windowService;
     private ListOperator _operator;
+    private bool _canOpenEditor;
 
     public ListOperatorPredicateNodeCustomViewModel(ListOperatorPredicateNode node, INodeScript script, IWindowService windowService) : base(node, script)
     {
         _node = node;
         _windowService = windowService;
 
-        OpenEditor = ReactiveCommand.CreateFromTask(ExecuteOpenEditor);
+        OpenEditor = ReactiveCommand.CreateFromTask(ExecuteOpenEditor, this.WhenAnyValue(vm => vm.CanOpenEditor));
+        CanOpenEditor = node.InputList.ConnectedTo.Any();
+        
+        this.WhenActivated(d =>
+        {
+            node.InputList.PinConnected += InputListOnPinConnected;
+            node.InputList.PinDisconnected += InputListOnPinDisconnected;
+
+            Disposable.Create(() =>
+            {
+                node.InputList.PinConnected -= InputListOnPinConnected;
+                node.InputList.PinDisconnected -= InputListOnPinDisconnected;
+            }).DisposeWith(d);
+        });
     }
 
     public ReactiveCommand<Unit, Unit> OpenEditor { get; }
 
+    private bool CanOpenEditor
+    {
+        get => _canOpenEditor;
+        set => this.RaiseAndSetIfChanged(ref _canOpenEditor, value);
+    }
+
     public ListOperator Operator
     {
         get => _operator;
@@ -40,4 +62,14 @@ public class ListOperatorPredicateNodeCustomViewModel : CustomNodeViewModel
         _node.Storage ??= new ListOperatorEntity();
         _node.Storage.Script = _node.Script.Entity;
     }
+
+    private void InputListOnPinDisconnected(object? sender, SingleValueEventArgs<IPin> e)
+    {
+        CanOpenEditor = false;
+    }
+
+    private void InputListOnPinConnected(object? sender, SingleValueEventArgs<IPin> e)
+    {
+        CanOpenEditor = true;
+    }
 }