using System;
using UnityEngine;
using UnityEngine.EventSystems;

/// <summary>
/// 打孔带在 UI 中的拖拽与点击交互。
/// </summary>
namespace AibisDream.FixSystem
{
    public class PunchTapeInteraction : MonoBehaviour, IPointerEnterHandler, IPointerExitHandler, IPointerClickHandler,
        IBeginDragHandler, IDragHandler, IEndDragHandler
    {
        private Canvas canvas;
        [HideInInspector]
        public bool isFavorited = false;

        private RectTransform rectTransform;

        private CursorMode cursorMode = CursorMode.Auto;

        private bool isLocked = false;
        private bool _favoriteDragActive;

        private void Awake()
        {
            rectTransform = GetComponent<RectTransform>();
        }

        private void OnEnable()
        {
            canvas = GetComponentInParent<Canvas>();
        }

        private void OnDisable()
        {
            if (_favoriteDragActive)
            {
                _favoriteDragActive = false;
                PunchTapeFavoritesDragEvents.NotifyDragEnded();
            }
        }

        public void OnPointerEnter(PointerEventData eventData)
        {
        }

        public void OnPointerExit(PointerEventData eventData)
        {
            Cursor.SetCursor(null, Vector2.zero, cursorMode);
        }

        public void OnPointerClick(PointerEventData eventData)
        {
        }

        public void OnBeginDrag(PointerEventData eventData)
        {
            if (!isFavorited || isLocked) return;

            transform.SetParent(canvas.transform, true);
            transform.localScale = Vector3.one;
            transform.SetAsLastSibling();
            var cg = GetComponent<CanvasGroup>();
            if (cg != null) cg.blocksRaycasts = false;
            _favoriteDragActive = true;
            PunchTapeFavoritesDragEvents.NotifyDragStarted();
        }

        public void OnDrag(PointerEventData eventData)
        {
            if (!isFavorited || isLocked) return;

            if (RectTransformUtility.ScreenPointToLocalPointInRectangle(
                canvas.transform as RectTransform,
                eventData.position,
                eventData.pressEventCamera,
                out Vector2 localPoint))
            {
                rectTransform.localPosition = new Vector3(localPoint.x, localPoint.y + 200f, 0f);
            }
            transform.rotation = Quaternion.Euler(0, 0, -90f);
        }

        public void OnEndDrag(PointerEventData eventData)
        {
            if (!isFavorited || isLocked) return;

            var cg = GetComponent<CanvasGroup>();
            if (cg != null) cg.blocksRaycasts = true;

            var slot = eventData.pointerEnter?
                .GetComponentInParent<MemoryPunchTapeSlot>();
            var item = GetComponent<PunchTapeItem>();

            bool accepted = slot != null && slot.TryAcceptDrop(item);

            if (_favoriteDragActive)
            {
                _favoriteDragActive = false;
                PunchTapeFavoritesDragEvents.NotifyDragEnded();
            }

            if (accepted)
            {
                Destroy(gameObject);
            }
            else
            {
                var manager = PunchTapeManager.Instance;
                if (manager != null && manager.FavoritesPanel != null)
                    manager.FavoritesPanel.ReturnToSlot(this);
            }
        }

        public void SetIsFavorited(bool favorited)
        {
            isFavorited = favorited;
        }

        public void SetIsLock(bool locked)
        {
            isLocked = locked;
        }
    }
}