Nodes - Added Enum Switch node

Nodes editor - Rewrite the way pin VMs are constructed

src/Artemis.VisualScripting/Nodes/Branching/EnumSwitchNode.cs

@@ -0,0 +1,97 @@
+using Artemis.Core;
+using Artemis.Core.Events;
+using Humanizer;
+
+namespace Artemis.VisualScripting.Nodes.Branching;
+
+[Node("Switch (Enum)", "Outputs the input that corresponds to the switch value", "Operators", InputType = typeof(Enum), OutputType = typeof(object))]
+public class EnumSwitchNode : Node
+{
+    private readonly Dictionary<Enum, InputPin> _inputPins;
+
+    public EnumSwitchNode() : base("Enum Branch", "desc")
+    {
+        _inputPins = new Dictionary<Enum, InputPin>();
+
+        Output = CreateOutputPin(typeof(object), "Result");
+        SwitchValue = CreateInputPin<Enum>("Switch");
+
+        SwitchValue.PinConnected += OnSwitchPinConnected;
+        SwitchValue.PinDisconnected += OnSwitchPinDisconnected;
+    }
+
+    public OutputPin Output { get; }
+    public InputPin<Enum> SwitchValue { get; }
+
+    public override void Evaluate()
+    {
+        if (SwitchValue.Value is null)
+        {
+            Output.Value = null;
+            return;
+        }
+
+        if (!_inputPins.TryGetValue(SwitchValue.Value, out InputPin? pin))
+        {
+            Output.Value = null;
+            return;
+        }
+
+        if (pin.ConnectedTo.Count == 0)
+        {
+            Output.Value = null;
+            return;
+        }
+
+        Output.Value = pin.Value;
+    }
+
+    private void OnInputPinDisconnected(object? sender, SingleValueEventArgs<IPin> e)
+    {
+        // if this is the last pin to disconnect, reset the type.
+        if (_inputPins.Values.All(i => i.ConnectedTo.Count == 0))
+            ChangeType(typeof(object));
+    }
+
+    private void OnInputPinConnected(object? sender, SingleValueEventArgs<IPin> e)
+    {
+        // change the type of our inputs and output
+        // depending on the first node the user connects to
+        ChangeType(e.Value.Type);
+    }
+
+    private void OnSwitchPinConnected(object? sender, SingleValueEventArgs<IPin> e)
+    {
+        if (SwitchValue.ConnectedTo.Count == 0)
+            return;
+
+        Type enumType = SwitchValue.ConnectedTo[0].Type;
+        foreach (Enum enumValue in Enum.GetValues(enumType).Cast<Enum>())
+        {
+            InputPin pin = CreateOrAddInputPin(typeof(object), enumValue.ToString().Humanize(LetterCasing.Sentence));
+            pin.PinConnected += OnInputPinConnected;
+            pin.PinDisconnected += OnInputPinDisconnected;
+            _inputPins[enumValue] = pin;
+        }
+    }
+
+    private void OnSwitchPinDisconnected(object? sender, SingleValueEventArgs<IPin> e)
+    {
+        foreach (InputPin input in _inputPins.Values)
+        {
+            input.PinConnected -= OnInputPinConnected;
+            input.PinDisconnected -= OnInputPinDisconnected;
+            RemovePin(input);
+        }
+
+        _inputPins.Clear();
+        ChangeType(typeof(object));
+    }
+
+    private void ChangeType(Type type)
+    {
+        foreach (InputPin input in _inputPins.Values)
+            input.ChangeType(type);
+        Output.ChangeType(type);
+    }
+}