using UnityEngine;
using UnityEditor;
using UnityEngine.UIElements;
using UnityEditor.UIElements;

[CustomEditor(typeof(EventController))]
public class EventControllerEditor : Editor
{
    private const string UxmlPath = "Assets/Scripts/Streamingle/StreamingleControl/Editor/UXML/EventControllerEditor.uxml";
    private const string CommonUssPath = "Assets/Scripts/Streamingle/StreamingleControl/Editor/UXML/StreamingleCommon.uss";

    private VisualElement eventsContainer;
    private Label eventsTitleLabel;
    private EventController controller;

    public override VisualElement CreateInspectorGUI()
    {
        controller = (EventController)target;
        var root = new VisualElement();

        var commonUss = AssetDatabase.LoadAssetAtPath<StyleSheet>(CommonUssPath);
        if (commonUss != null) root.styleSheets.Add(commonUss);

        var uxml = AssetDatabase.LoadAssetAtPath<VisualTreeAsset>(UxmlPath);
        if (uxml != null) uxml.CloneTree(root);

        BuildEventGroupsSection(root);

        Undo.undoRedoPerformed += OnUndoRedo;
        root.RegisterCallback<DetachFromPanelEvent>(_ => Undo.undoRedoPerformed -= OnUndoRedo);

        return root;
    }

    private void OnUndoRedo()
    {
        if (controller == null) return;
        serializedObject.Update();
        RebuildEventList();
    }

    #region Event Groups List

    private void BuildEventGroupsSection(VisualElement root)
    {
        var section = root.Q("eventGroupsSection");
        if (section == null) return;

        var header = new VisualElement();
        header.AddToClassList("list-header");

        eventsTitleLabel = new Label($"Event Groups ({controller.eventGroups.Count})");
        eventsTitleLabel.AddToClassList("list-title");
        header.Add(eventsTitleLabel);

        var addBtn = new Button(AddEventGroup) { text = "+ 이벤트 추가" };
        addBtn.AddToClassList("list-add-btn");
        header.Add(addBtn);

        section.Add(header);

        eventsContainer = new VisualElement();
        section.Add(eventsContainer);

        RebuildEventList();
    }

    private void RebuildEventList()
    {
        if (eventsContainer == null || controller == null) return;
        eventsContainer.Clear();

        if (eventsTitleLabel != null)
            eventsTitleLabel.text = $"Event Groups ({controller.eventGroups.Count})";

        if (controller.eventGroups.Count == 0)
        {
            var empty = new Label("이벤트 그룹이 없습니다. '+ 이벤트 추가' 버튼을 눌러 추가하세요.");
            empty.AddToClassList("list-empty");
            eventsContainer.Add(empty);
            return;
        }

        for (int i = 0; i < controller.eventGroups.Count; i++)
        {
            eventsContainer.Add(CreateEventGroupElement(i));
        }
    }

    private VisualElement CreateEventGroupElement(int index)
    {
        var group = controller.eventGroups[index];

        var item = new VisualElement();
        item.AddToClassList("list-item");

        // Header row
        var headerRow = new VisualElement();
        headerRow.AddToClassList("list-item-header");

        var indexLabel = new Label($"{index + 1}");
        indexLabel.AddToClassList("list-index");
        headerRow.Add(indexLabel);

        var nameField = new TextField();
        nameField.value = group.groupName;
        nameField.AddToClassList("list-name-field");
        int idx = index;
        nameField.RegisterValueChangedCallback(evt =>
        {
            Undo.RecordObject(target, "Rename Event Group");
            controller.eventGroups[idx].groupName = evt.newValue;
            EditorUtility.SetDirty(target);
        });
        headerRow.Add(nameField);

        // Reorder buttons
        var upBtn = new Button(() => SwapEvents(idx, idx - 1)) { text = "\u25B2" };
        upBtn.AddToClassList("list-reorder-btn");
        upBtn.SetEnabled(index > 0);
        headerRow.Add(upBtn);

        var downBtn = new Button(() => SwapEvents(idx, idx + 1)) { text = "\u25BC" };
        downBtn.AddToClassList("list-reorder-btn");
        downBtn.SetEnabled(index < controller.eventGroups.Count - 1);
        headerRow.Add(downBtn);

        var deleteBtn = new Button(() => DeleteEvent(idx)) { text = "X" };
        deleteBtn.AddToClassList("list-delete-btn");
        headerRow.Add(deleteBtn);

        item.Add(headerRow);

        // Fields - UnityEvent uses PropertyField for the built-in event drawer
        var fields = new VisualElement();
        fields.AddToClassList("list-fields");

        var listProp = serializedObject.FindProperty("eventGroups");
        var elementProp = listProp.GetArrayElementAtIndex(index);

        var eventField = new PropertyField(elementProp.FindPropertyRelative("unityEvent"), "Event");
        fields.Add(eventField);

        item.Add(fields);
        return item;
    }

    private void AddEventGroup()
    {
        Undo.RecordObject(target, "Add Event Group");
        controller.eventGroups.Add(new EventController.EventGroup("New Event"));
        EditorUtility.SetDirty(target);
        serializedObject.Update();
        RebuildEventList();
    }

    private void DeleteEvent(int index)
    {
        var group = controller.eventGroups[index];
        if (EditorUtility.DisplayDialog("이벤트 삭제",
            $"이벤트 '{group.groupName}'을(를) 삭제하시겠습니까?", "삭제", "취소"))
        {
            Undo.RecordObject(target, "Delete Event Group");
            controller.eventGroups.RemoveAt(index);
            EditorUtility.SetDirty(target);
            serializedObject.Update();
            RebuildEventList();
        }
    }

    private void SwapEvents(int a, int b)
    {
        Undo.RecordObject(target, "Reorder Event Groups");
        (controller.eventGroups[a], controller.eventGroups[b]) = (controller.eventGroups[b], controller.eventGroups[a]);
        EditorUtility.SetDirty(target);
        serializedObject.Update();
        RebuildEventList();
    }

    #endregion
}