using UnityEngine;
using UnityEngine.EventSystems;

namespace UI.CardSystem.StateMachine.States
{
    /// <summary>
    /// Optional helper component for handling drag/drop integration with existing DragDrop system.
    /// Can be attached to Card root to bridge between state machine and drag system.
    /// </summary>
    public class CardInteractionHandler : MonoBehaviour, IBeginDragHandler, IDragHandler, IEndDragHandler
    {
        private CardContext _context;
        private CardDraggingState _draggingState;
        private bool _isDragging;
        
        private void Awake()
        {
            _context = GetComponent<CardContext>();
        }
        
        public void OnBeginDrag(PointerEventData eventData)
        {
            // Only allow drag from certain states
            var currentState = _context.StateMachine.currentState?.name;
            if (currentState != "RevealedState" && currentState != "PlacedInSlotState")
            {
                return;
            }
            
            // Transition to dragging state
            _context.StateMachine.ChangeState("DraggingState");
            _draggingState = _context.StateMachine.currentState?.GetComponent<CardDraggingState>();
            _isDragging = true;
        }
        
        public void OnDrag(PointerEventData eventData)
        {
            if (!_isDragging || _draggingState == null) return;
            
            // Update drag position
            Vector3 worldPosition;
            RectTransformUtility.ScreenPointToWorldPointInRectangle(
                transform as RectTransform,
                eventData.position,
                eventData.pressEventCamera,
                out worldPosition
            );
            
            // _draggingState.UpdateDragPosition(worldPosition);
        }
        
        public void OnEndDrag(PointerEventData eventData)
        {
            if (!_isDragging || _draggingState == null) return;
            
            _isDragging = false;
            
            // Check if dropped over a valid slot
            // This would integrate with your existing AlbumCardSlot system
            // For now, just return to revealed state
            // _draggingState.OnDroppedOutsideSlot();
        }
    }
}