using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.InputSystem;
using UnityEngine.InputSystem.UI;

namespace NEG.UI.UnityUi
{
    public enum SelectionSource
    {
        Pointer,
        Direction
    }

    public class UiInputModule { }

    public class DefaultInputModule : UiInputModule
    {
        public SelectionSource CurrentSelectionSource { get; private set; }
        
        public DefaultInputModule()
        {
            var defaultActions = new DefaultInputActions();
            InputActionReference.Create(defaultActions.UI.Navigate).action.performed += (ctx) => OnSelectionChangeStarted();
            defaultActions.Enable();

            if (Gamepad.current != null)
                SetDirectionInput();
            else
                SetPointerInput();

            //var keyboardAction = new InputAction(binding: "/<Keyboard>/*");
            //keyboardAction.performed += (context) => CurrentInputSource = EInputSource.Keyboard;
            //keyboardAction.Enable();
            var gamepadAction = new InputAction(binding: "/<Gamepad>/*");
            gamepadAction.performed += (context) => OnSelectionChangeStarted();
            gamepadAction.Enable();
            
            var mouseAction = new InputAction(binding: "/<Mouse>/*");
            mouseAction.performed += (context) =>
            {
                if(CurrentSelectionSource == SelectionSource.Pointer)
                    return;
                SetPointerInput();
            };
            mouseAction.Enable();
        }

        private void OnSelectionChangeStarted()
        {
            if(CurrentSelectionSource == SelectionSource.Direction)
                return;
            SetDirectionInput();
        }

        private void SetDirectionInput()
        {
            CurrentSelectionSource = SelectionSource.Direction;
            Cursor.visible = false;
        }

        private void SetPointerInput()
        {
            CurrentSelectionSource = SelectionSource.Pointer;
            Cursor.visible = true;

            if (EventSystem.current == null)
            {
                SetDirectionInput();
                return;
            }

            if (EventSystem.current.currentInputModule == null) 
                return;
            
            var module = (InputSystemUIInputModule)EventSystem.current.currentInputModule;
            var result = module.GetLastRaycastResult(0);
            if(result.gameObject == null)
                return;
            
            var data = new PointerEventData(EventSystem.current);
            for (var current = result.gameObject.transform;
                 current != null;
                 current = current.parent)
            {
                ExecuteEvents.Execute(current.gameObject, data, ExecuteEvents.pointerEnterHandler);
            }
        }
    }
}