using System.Collections.Generic;
using System.Linq;
using UnityEditor;

using UnityEngine;
using UnityEngine.UIElements;
using Unity.Mathematics;
using static Unity.Mathematics.math;

[CustomEditor(typeof(ClusterPrefab))]
public class ClusterInspector : Editor {
    protected static VisualElement mainContainer;
    protected static VisualElement inspectorContainer;

    protected bool breakOnWake = false;

    #region Start

    public override VisualElement CreateInspectorGUI() {
        ClusterPrefab cluster = target as ClusterPrefab;
        if (cluster != null)
            cluster.EnsureInitialization();

        serializedObject.Update();

        VisualElement root = new();
        CreateInspector(root, cluster);

        serializedObject.ApplyModifiedProperties();
        return root;
    }

    public static GraphView CreateInspector(VisualElement root, ClusterPrefab cluster) {
        root.style.paddingLeft = 0;
        root.style.paddingRight = 0;
        root.style.paddingTop = 0;
        root.style.paddingBottom = 0;

        root.styleSheets.Add(Resources.Load<StyleSheet>("GraphStyles"));

        // does the main container have added value?
        // is just is like the root
        mainContainer = new() {
            style = {
                height = 450,
                flexDirection = FlexDirection.Row
                }
        };
        GraphView graph = new(cluster);
        graph.style.flexGrow = 1;

        inspectorContainer = new VisualElement {
            name = "inspector",
            style = {
                width = 300,
                flexGrow = 0
            }
        };

        mainContainer.Add(graph);
        mainContainer.Add(inspectorContainer);
        root.Add(mainContainer);

        graph.SetGraph(null, cluster.output, inspectorContainer);

        return graph;
    }


    public class GraphView : VisualElement {
        readonly ClusterPrefab cluster;
        SerializedObject serializedBrain;
        Nucleus currentNucleus;
        GameObject gameObject;
        private List<NeuroidLayer> layers = new();
        private readonly Dictionary<Nucleus, Vector2Int> neuroidPositions = new();
        private bool expandArray = false;

        ClusterWrapper currentWrapper;
        PopupField<string> outputsField;

        public GraphView(ClusterPrefab prefab) {
            this.cluster = prefab;

            name = "content";
            style.flexGrow = 1;

            IMGUIContainer graphContainer = new(OnIMGUI);
            graphContainer.style.position = Position.Absolute;
            graphContainer.style.left = 0; graphContainer.style.top = 0;
            graphContainer.style.right = 0; graphContainer.style.bottom = 0;
            graphContainer.pickingMode = PickingMode.Position;
            graphContainer.focusable = true;
            Add(graphContainer);

            VisualElement outputContainer = new() {
                style = {
                    flexDirection = FlexDirection.Row,
                    alignItems = Align.Center,
                }
            };

            List<string> names = this.cluster.outputs.Select(output => output.name).ToList();
            outputsField = new(names, names.First()) {
                style = { flexGrow = 1 }
            };
            outputsField.RegisterValueChangedCallback(evt => OnOutputChanged(evt.newValue));
            outputContainer.Add(outputsField);

            Button addButton = new(() => OnAddClusterOutput()) {
                text = "Add"
            };
            outputContainer.Add(addButton);

            Add(outputContainer);

            // Subscribe when added to panel (editor UI ready)
            RegisterCallback<AttachToPanelEvent>(evt => Subscribe());
            RegisterCallback<DetachFromPanelEvent>(evt => Unsubscribe());
        }

        void OnOutputChanged(string outputName) {
            this.currentNucleus = this.cluster.GetNucleus(outputName);
        }

        void OnAddClusterOutput() {
            Nucleus newOutput = new Neuron(this.cluster, "Output 2");

            outputsField.choices = this.cluster.outputs.Select(output => output.name).ToList();
            outputsField.value = newOutput.name;

            this.currentNucleus = newOutput;
        }

        bool subscribed = false;
        void Subscribe() {
            if (subscribed) return;
            SceneView.duringSceneGui += OnSceneGUI;
            subscribed = true;
            SceneView.RepaintAll();
        }

        void Unsubscribe() {
            if (!subscribed) return;
            SceneView.duringSceneGui -= OnSceneGUI;
            subscribed = false;
        }

        public void SetGraph(GameObject gameObject, Nucleus nucleus, VisualElement inspectorContainer) {
            this.gameObject = gameObject;
            //this.cluster = brain;
            if (Application.isPlaying == false)
                this.serializedBrain = new SerializedObject(this.cluster);
            this.currentNucleus = nucleus;
            Rebuild(inspectorContainer);
        }

        void Rebuild(VisualElement inspectorContainer) {
            BuildLayers();

            if (this.currentNucleus == null) {
                inspectorContainer.Clear();
                return;
            }

            if (currentWrapper != null)
                DestroyImmediate(currentWrapper);
            currentWrapper = CreateInstance<ClusterWrapper>().Init(this.currentNucleus, cluster);
            DrawInspector(inspectorContainer);
        }

        private void BuildLayers() {
            // A temporary list to track what's been added to layers
            this.layers = new();
            int layerIx = 0;

            Nucleus selectedNucleus = this.currentNucleus;
            if (selectedNucleus == null)
                return;
            NeuroidLayer currentLayer = new() { ix = layerIx };

            if (selectedNucleus.receivers != null) {
                foreach (Nucleus receiver in selectedNucleus.receivers) {
                    Nucleus outputNeuroid = receiver;
                    if (outputNeuroid != null) {
                        AddToLayer(currentLayer, outputNeuroid);
                        // Debug.Log($"layer {layerIx} nucleus {outputNeuroid.name}");
                    }
                }
            }
            if (currentLayer.neuroids.Count > 0) {
                this.layers.Add(currentLayer);
                layerIx++;
                currentLayer = new() { ix = layerIx };
            }

            AddToLayer(currentLayer, selectedNucleus);
            this.layers.Add(currentLayer);
            // Debug.Log($"layer {layerIx} nucleus {selectedNucleus.name}");

            layerIx++;
            currentLayer = new() { ix = layerIx };

            if (selectedNucleus.synapses != null) {
                foreach (Synapse synapse in selectedNucleus.synapses) {
                    Nucleus input = synapse.nucleus;
                    AddToLayer(currentLayer, input);
                    // Debug.Log($"layer {layerIx} nucleus {input.name}");
                }
            }
            if (currentLayer.neuroids.Count > 0) {
                this.layers.Add(currentLayer);
            }
        }

        private void AddToLayer(NeuroidLayer layer, Nucleus nucleus) {
            if (nucleus == null)
                return;
            layer.neuroids.Add(nucleus);
            //nucleus.layerIx = layer.ix;
            // Store its position
            Vector2Int neuroidPosition = new(layer.ix, layer.neuroids.Count - 1);
            neuroidPositions[nucleus] = neuroidPosition;

        }


        public void OnIMGUI() {
            if (currentNucleus == null)
                return;

            if (Application.isPlaying == false)
                serializedBrain.Update();

            Handles.BeginGUI();
            DrawGraph();
            Handles.EndGUI();

        }

        private void DrawGraph() {
            float size = 20;
            Vector3 position = new(150, 210, 0);

            DrawReceivers(this.currentNucleus, position, size);
            DrawSynapses(this.currentNucleus, position, size);

            // Draw selected Nucleus
            if (expandArray) {
                float maxValue = 0;
                foreach (Nucleus nucleus in this.currentNucleus.array.nuclei) {
                    float value = length(nucleus.outputValue);
                    if (value > maxValue)
                        maxValue = value;
                }

                float spacing = 400f / this.currentNucleus.array.nuclei.Count();
                float margin = 10 + spacing / 2;
                float xMin = 150 - size;
                float xMax = 150 + size;
                float yMin = 10 + margin - size / 2;
                float yMax = 400 - margin + size;
                Vector3[] verts = new Vector3[4] {
                    new(xMin, yMin, 0),
                    new(xMax, yMin, 0),
                    new(xMax, yMax, 0),
                    new(xMin, yMax, 0)
                };
                Handles.color = Color.black;
                Handles.DrawAAConvexPolygon(verts);
                int row = 0;
                foreach (Nucleus nucleus in this.currentNucleus.array.nuclei) {
                    Vector3 pos = new(150, margin + row * spacing, 0.0f);
                    Handles.color = Color.white;
                    // The selected nucleus highlight ring
                    Handles.DrawSolidDisc(pos, Vector3.forward, size + 2);
                    DrawNucleus(nucleus, pos, maxValue, size);
                    row++;
                }
                // GUIStyle style = new(EditorStyles.label) {
                //     alignment = TextAnchor.UpperCenter,
                //     normal = { textColor = Color.white },
                //     fontStyle = FontStyle.Bold,
                // };
                // Vector3 labelPos = new Vector3(150, yMax, 0) - Vector3.down * (size + 25); // below disc along up axis
                // Handles.Label(labelPos, this.currentNucleus.name, style);
            }
            else {
                Handles.color = Color.white;
                // The selected nucleus highlight ring
                Handles.DrawSolidDisc(position, Vector3.forward, size + 2);
                DrawNucleus(this.currentNucleus, position, length(this.currentNucleus.outputValue), 20);
            }
        }

        private void DrawReceivers(Nucleus nucleus, Vector3 parentPos, float size) {
            int nodeCount = nucleus.receivers.Count();

            // Determine the maximum value in this layer
            // This is used to 'scale' the output value colors of the nuclei
            float maxValue = 0;
            foreach (Nucleus receiver in nucleus.receivers) {
                if (receiver is Neuron neuroid) {
                    float value = length(neuroid.outputValue);
                    if (value > maxValue)
                        maxValue = value;
                }
            }

            // Determine the spacing of the nuclei in the layer
            float spacing = 400f / nodeCount;
            float margin = 10 + spacing / 2;

            int row = 0;
            List<NucleusArray> drawnArrays = new();
            foreach (Nucleus receiver in nucleus.receivers) {
                if (drawnArrays.Contains(receiver.array))
                    continue;
                drawnArrays.Add(receiver.array);

                Nucleus receiverNucleus = receiver;
                if (receiverNucleus == null)
                    continue;

                Vector3 pos = new(50, margin + row * spacing, 0.0f);
                Handles.color = Color.white;
                Handles.DrawLine(parentPos, pos);

                DrawNucleus(receiverNucleus, pos, maxValue, size);
                row++;
            }
        }

        private void DrawSynapses(Nucleus nucleus, Vector3 parentPos, float size) {
            int nodeCount = nucleus.synapses.Count;

            // Determine the maximum value in this layer
            // This is used to 'scale' the output value colors of the nuclei
            float maxValue = 0;
            int neuronCount = 0;
            List<NucleusArray> drawnArrays = new();
            foreach (Synapse synapse in nucleus.synapses) {
                if (synapse.nucleus is Neuron neuroid) {
                    if (drawnArrays.Contains(neuroid.array))
                        continue;
                    drawnArrays.Add(neuroid.array);

                }
                float value = length(synapse.nucleus.outputValue) * synapse.weight;
                // Debug.Log($"{synapse.nucleus.name}: {value}  {length(synapse.nucleus.outputValue)} {synapse.weight}");
                if (value > maxValue)
                    maxValue = value;
                neuronCount++;
            }

            // Determine the spacing of the nuclei in the layer
            float spacing = 400f / neuronCount;
            float margin = 10 + spacing / 2;

            int row = 0;
            drawnArrays = new();
            foreach (Synapse synapse in nucleus.synapses) {
                if (synapse.nucleus is Neuron neuron) {
                    if (drawnArrays.Contains(neuron.array))
                        continue;
                    drawnArrays.Add(neuron.array);
                }
                Vector3 pos = new(250, margin + row * spacing, 0.0f);
                Handles.color = Color.white;
                Handles.DrawLine(parentPos, pos);
                if (synapse.nucleus != null) {
                    Color color = Color.black;
                    if (synapse.nucleus.isSleeping)
                        color = Color.darkRed;
                    else if (Application.isPlaying) {
                        float brightness = length(synapse.nucleus.outputValue) * synapse.weight / maxValue;
                        color = new Color(brightness, brightness, brightness, 1f);
                    }
                    DrawNucleus(synapse.nucleus, pos, maxValue, size, color);
                }
                row++;
            }
        }

        private void DrawNucleus(Nucleus nucleus, Vector3 position, float maxValue, float size) {
            Color color;
            if (nucleus.isSleeping)
                color = Color.darkRed;
            else {
                if (Application.isPlaying) {
                    float brightness = length(nucleus.outputValue) / maxValue;
                    color = new Color(brightness, brightness, brightness, 1f);
                }
                else
                    color = Color.black;
            }
            DrawNucleus(nucleus, position, maxValue, size, color);
        }

        private void DrawNucleus(Nucleus nucleus, Vector3 position, float maxValue, float size, Color color) {
            if (nucleus is MemoryCell memory) {
                Handles.color = Color.white;
                Handles.DrawWireDisc(position + Vector3.right * 10, Vector3.forward, size);
            }

            Handles.color = color;
            Handles.DrawSolidDisc(position, Vector3.forward, size);

            Handles.color = Color.white;
            // Position the label in front of the disc
            Vector3 labelPosition = position + (Vector3.forward * 0.1f);

            GUIStyle style = new(EditorStyles.label) {
                alignment = TextAnchor.MiddleCenter,
                normal = { textColor = Color.white },
                fontStyle = FontStyle.Bold,
            };
            if (nucleus is Nucleus neuron) {
                if (neuron.array == null || neuron.array.nuclei == null || neuron.array.nuclei.Count() == 0)
                    neuron.array = new NucleusArray(neuron);

                if ((!expandArray || neuron.array.nuclei.First() != this.currentNucleus) && neuron.array.nuclei.Count() > 1) {
                    Handles.Label(labelPosition, neuron.array.nuclei.Count().ToString(), style);
                }
                if (expandArray && neuron.array.nuclei.First() == this.currentNucleus) {
                    int arrayIx = 0;
                    foreach (Nucleus n in neuron.array.nuclei) {
                        if (n == neuron)
                            break;
                        arrayIx++;
                    }
                    Handles.Label(labelPosition, $"[{arrayIx}]", style);
                }
                else {
                    style.alignment = TextAnchor.UpperCenter;
                    Vector3 labelPos = position - Vector3.down * (size + 10f); // below disc along up axis
                    int colonPos = nucleus.name.IndexOf(":");
                    if (colonPos > 0) {
                        string baseName = nucleus.name[..colonPos];
                        Handles.Label(labelPos, baseName, style);
                    }
                    else
                        Handles.Label(labelPos, nucleus.name, style);
                }

                if (nucleus is Cluster cluster) {
                    Handles.color = Color.white;
                    Handles.DrawWireDisc(position, Vector3.forward, size + 10);
                }
            }
            else {
                style.alignment = TextAnchor.UpperCenter;
                Vector3 labelPos = position - Vector3.down * (size + 10); // below disc along up axis
                Handles.Label(labelPos, nucleus.name, style);
            }

            Rect neuronRect = new(position.x - size, position.y - size, size * 2, size * 2);
            int id = GUIUtility.GetControlID(FocusType.Passive);
            Event e = Event.current;
            EventType et = e.GetTypeForControl(id);
            if (e != null && neuronRect.Contains(e.mousePosition)) {
                // Process Hover
                HandleMouseHover(nucleus, neuronRect);
                // Process click
                if (e.type == EventType.MouseDown && e.button == 0) {
                    // Consume the event so the scene doesn't also handle it
                    e.Use();
                    HandleClicked(nucleus);
                }
            }
        }

        private void HandleMouseHover(Nucleus nucleus, Rect rect) {
            GUIContent tooltip;
            tooltip = new(
                $"{nucleus.name}" +
                $"\nValue: {length(nucleus.outputValue)}");

            Vector2 mousePosition = Event.current.mousePosition;

            // Display tooltip with some offset
            Vector2 tooltipSize = GUI.skin.box.CalcSize(tooltip);
            Rect tooltipRect = new Rect(mousePosition.x + 10, mousePosition.y + 10, tooltipSize.x, tooltipSize.y);

            GUI.Box(tooltipRect, tooltip);
        }

        private void HandleClicked(Nucleus nucleus) {
            if (nucleus == this.currentNucleus) {
                if (nucleus is Nucleus n) {
                    expandArray = !expandArray;
                    return;
                }
            }
            else if (nucleus is Nucleus n) {
                this.currentNucleus = n;
                BuildLayers();
            }
        }

        private int selectedInputType = 0;
        void DrawInspector(VisualElement inspectorContainer) {
            if (inspectorContainer == null)
                return;

            inspectorContainer.Clear();
            if (this.currentNucleus == null)
                return;

            // create a SerializedObject wrapper so Unity inspector controls work (and Undo)
            SerializedObject so = new(currentWrapper);
            IMGUIContainer container = new(() => {
                if (so.targetObject == null)
                    return;
                so.Update();

                if (this.currentNucleus == null)
                    return;

                GUIStyle headerStyle = new GUIStyle(EditorStyles.boldLabel) {
                    alignment = TextAnchor.MiddleLeft,
                    margin = new RectOffset(10, 0, 4, 4)
                };
                //GUI.backgroundColor = EditorGUIUtility.isProSkin ? new Color(0.15f, 0.15f, 0.15f) : new Color(0.85f, 0.85f, 0.85f);
                //GUILayout.BeginVertical("box");
                GUIStyle boldTextFieldStyle = new GUIStyle(EditorStyles.textField) {
                    fontStyle = FontStyle.Bold
                };

                GUILayout.Label(this.currentNucleus.GetType().ToString(), headerStyle);
                //GUILayout.EndVertical();
                //GUI.backgroundColor = Color.white; // Reset background color
                this.currentNucleus.name = EditorGUILayout.TextField(this.currentNucleus.name, boldTextFieldStyle);
                if (this.currentNucleus is Neuron neuroid) {
                    if (this.currentNucleus is MemoryCell memory) {
                    }
                    else {
                        EditorGUILayout.BeginHorizontal();
                        EditorGUILayout.LabelField("Activation Curve", GUILayout.Width(150));
                        if (neuroid.curveMax > 0)
                            EditorGUILayout.CurveField(neuroid.curve, Color.cyan, new Rect(0, 0, 1, neuroid.curveMax));
                        else
                            EditorGUILayout.CurveField(neuroid.curve, Color.cyan, new Rect(0, neuroid.curveMax, 1, -neuroid.curveMax));
                        neuroid.curvePreset = (Neuron.CurvePresets)EditorGUILayout.EnumPopup(neuroid.curvePreset, GUILayout.Width(100));
                        EditorGUILayout.EndHorizontal();
                    }

                    if (neuroid.array == null || neuroid.array.nuclei == null || neuroid.array.nuclei.Count() == 0)
                        neuroid.array = new NucleusArray(neuroid);
                    EditorGUILayout.BeginHorizontal();
                    EditorGUILayout.IntField("Array size", neuroid.array.nuclei.Count());
                    if (GUILayout.Button("Add"))
                        neuroid.array.AddNucleus(this.cluster);
                    if (GUILayout.Button("Del"))
                        neuroid.array.RemoveNucleus();
                    EditorGUILayout.EndHorizontal();
                }

                if (Application.isPlaying)
                    EditorGUILayout.FloatField("Output", length(this.currentNucleus.outputValue));
                else
                    EditorGUILayout.LabelField(" ");

                if (this.currentNucleus.synapses.Count > 0) {
                    EditorGUILayout.LabelField("Synapses");
                    Synapse[] synapses = this.currentNucleus.synapses.ToArray();
                    foreach (Synapse synapse in synapses) {
                        if (synapse.nucleus != null) {
                            EditorGUILayout.Space();

                            //EditorGUI.BeginDisabledGroup(synapse.nucleus.isSleeping);
                            if (Application.isPlaying)
                                EditorGUILayout.FloatField(synapse.nucleus.name, length(synapse.nucleus.outputValue) * synapse.weight);
                            else {
                                EditorGUILayout.BeginHorizontal();
                                EditorGUILayout.LabelField(synapse.nucleus.name);
                                if (GUILayout.Button("Disconnect"))
                                    synapse.nucleus.RemoveReceiver(this.currentNucleus);
                                EditorGUILayout.EndHorizontal();
                            }

                            EditorGUI.indentLevel++;
                            synapse.weight = EditorGUILayout.FloatField("Weight", synapse.weight);
                            EditorGUI.indentLevel--;
                            //EditorGUI.EndDisabledGroup();
                        }
                    }
                }

                EditorGUILayout.Space();

                ConnectNucleus(this.cluster, this.currentNucleus);

                EditorGUILayout.BeginHorizontal();
                string[] options = { "Neuron", "MemoryCell", "Selector", "Cluster" };
                selectedInputType = EditorGUILayout.Popup(selectedInputType, options);
                if (GUILayout.Button("Add Input"))
                    AddInput(selectedInputType, this.currentNucleus);
                EditorGUILayout.EndHorizontal();

                // if (GUILayout.Button("Add Input Neuron"))
                //     AddInputNeuron(this.currentNucleus);
                // if (GUILayout.Button("Add Input MemoryCell"))
                //     AddInputMemoryCell(this.currentNucleus);
                // if (GUILayout.Button("Add Input Cluster"))
                //     AddCluster(this.currentNucleus);

                EditorGUILayout.Space();

                if (GUILayout.Button("Delete this neuron"))
                    DeleteNeuron(this.currentNucleus);

                if (this.currentNucleus is Cluster subCluster) {
                    if (GUILayout.Button("Edit Cluster"))
                        EditCluster(subCluster);
                }

                // if (this.gameObject != null) {
                //     Vector3 worldVector = this.gameObject.transform.TransformVector(this.currentNucleus.outputValue);
                //     //Debug.DrawRay(this.gameObject.transform.position, worldVector, Color.yellow);
                //     Handles.color = Color.yellow;
                //     Handles.DrawLine(this.gameObject.transform.position, this.gameObject.transform.position + worldVector);
                // }
            });

            inspectorContainer.Add(container);
        }

        void OnSceneGUI(SceneView sceneView) {
            if (this.gameObject != null) {
                Vector3 worldVector = this.gameObject.transform.TransformVector(this.currentNucleus.outputValue);
                Handles.color = Color.yellow;
                Handles.DrawLine(this.gameObject.transform.position, this.gameObject.transform.position + worldVector);
            }
        }

        protected virtual void AddInput(int selectedInputType, Nucleus nucleus) {
            switch (selectedInputType) {
                case 0: // Neuron
                    AddInputNeuron(nucleus);
                    break;
                case 1: // MemoryCell
                    AddInputMemoryCell(nucleus);
                    break;
                case 2: // Selector
                    AddSelectorInput(nucleus);
                    break;
                case 3: // Cluster
                    AddCluster(nucleus);
                    break;
            }
        }

        protected virtual void AddInputNeuron(Nucleus nucleus) {
            //Neuron newNeuroid = new(this.cluster, "New neuron");
            Neuron newNeuroid = new(this.cluster, "New neuron");
            newNeuroid.AddReceiver(nucleus);
            this.currentNucleus = newNeuroid;
            BuildLayers();
        }

        protected virtual void DeleteNeuron(Nucleus nucleus) {
            if (nucleus == null)
                return;
            if (nucleus.cluster != null)
                this.currentNucleus = nucleus.cluster.output;
            foreach (Nucleus receiver in nucleus.receivers) {
                if (receiver != null) {
                    this.currentNucleus = receiver;
                    break;
                }
            }
            Neuron.Delete(nucleus);
            BuildLayers();
        }

        protected void AddSelectorInput(Nucleus nucleus) {
            Selector newSelector = new(this.cluster, "New Selector");
            newSelector.AddReceiver(nucleus);
            this.currentNucleus = newSelector;
            BuildLayers();
        }

        protected virtual void AddInputMemoryCell(Nucleus nucleus) {
            MemoryCell newMemory = new(this.cluster, "New memory cell");
            newMemory.AddReceiver(nucleus);
            this.currentNucleus = newMemory;
            BuildLayers();
        }

        protected virtual void AddCluster(Nucleus nucleus) {
            ClusterPickerWindow.ShowPicker(brain => OnClusterPicked(nucleus, brain), "Select Cluster");
        }

        private void OnClusterPicked(Nucleus nucleus, ClusterPrefab prefab) {
            Cluster subclusterInstance = new(prefab, this.cluster);
            subclusterInstance.AddReceiver(nucleus);
            // This does not work somehow
            // this.currentNucleus = subclusterInstance;
            // BuildLayers();
        }

        private void EditCluster(Cluster subCluster) {
            // May be used with storedPrefab...
            Selection.activeObject = subCluster.prefab;
            EditorGUIUtility.PingObject(subCluster.prefab);
            var editor = Editor.CreateEditor(subCluster.prefab);
        }

        // Connect to another nucleus in the same cluster
        protected virtual void ConnectNucleus(ClusterPrefab cluster, Nucleus nucleus) {
            if (cluster == null)
                return;

            IEnumerable<Nucleus> synapseNuclei = this.currentNucleus.synapses
                .Where(synapse => synapse.nucleus != null)
                .Select(synapse => synapse.nucleus);

            IEnumerable<Nucleus> nuclei = cluster.nuclei
                .Except(synapseNuclei);
            IEnumerable<string> nucleiNames = nuclei.Select(n => n.name);

            string[] names = nucleiNames.ToArray();
            int selectedIndex = -1;
            selectedIndex = EditorGUILayout.Popup("Connect to", selectedIndex, names);
            if (selectedIndex >= 0) {
                Nucleus receptor = nuclei.ElementAt(selectedIndex);
                receptor.AddReceiver(this.currentNucleus);
            }
        }

        protected virtual void DisconnectNucleus(Neuron nucleus) {
            if (this.currentNucleus.cluster == null)
                return;
            string[] names = this.currentNucleus.synapses.Select(synapse => synapse.nucleus.name).ToArray();
            int selectedIndex = -1;
            selectedIndex = EditorGUILayout.Popup("Disconnect from", selectedIndex, names);
            //if (selectedIndex >= 0 && selectedIndex < this.currentNucleus.brain.perceptei.Count) {
            if (selectedIndex >= 0 && selectedIndex < this.currentNucleus.cluster.nuclei.Count) {
                Synapse synapse = this.currentNucleus.synapses[selectedIndex];
                synapse.nucleus.RemoveReceiver(this.currentNucleus);
            }
        }
    }

    #endregion Start    

}

public class NeuroidLayer {
    public int ix = 0;
    public List<Nucleus> neuroids = new();
}

public class ClusterWrapper : ScriptableObject {
    // expose fields that map to GraphNode
    //public string title;
    public Vector2 position;
    Nucleus node;
    ClusterPrefab graph; // needed to write back and mark dirty

    public ClusterWrapper Init(Nucleus node, ClusterPrefab graphAsset) {
        this.node = node;
        this.graph = graphAsset;
        //this.title = " A " + node.name;
        //position = node.position;
        return this;
    }
    void OnValidate() {
        if (node != null) {
            //node.name = title;
            //node.position = position;
#if UNITY_EDITOR
            if (graph != null)
                UnityEditor.EditorUtility.SetDirty(graph);
#endif
        }
    }
}