using Core;
using Core.SaveLoad;
using UnityEngine;

namespace UI.CardSystem.StateMachine.States
{
    /// <summary>
    /// Card is in pending face-down state in corner, awaiting drag.
    /// On drag start, triggers flip animation and transitions to revealed dragging.
    /// </summary>
    public class CardPendingFaceDownState : AppleState, ICardStateDragHandler
    {
        [Header("State-Owned Visuals")]
        [SerializeField] private GameObject cardBackVisual;
        
        private CardContext _context;
        private bool _isFlipping;
        
        private void Awake()
        {
            _context = GetComponentInParent<CardContext>();
        }
        
        public override void OnEnterState()
        {
            if (_context == null) return;
            
            _isFlipping = false;
            
            // Show card back, hide card front
            if (cardBackVisual != null)
            {
                cardBackVisual.SetActive(true);
                cardBackVisual.transform.localRotation = Quaternion.Euler(0, 0, 0);
            }
            
            if (_context.CardDisplay != null)
            {
                _context.CardDisplay.gameObject.SetActive(false);
                _context.CardDisplay.transform.localRotation = Quaternion.Euler(0, 180, 0);
            }
            
            // Scale down for corner display
            _context.RootTransform.localScale = _context.OriginalScale * 0.8f;
        }
        
        /// <summary>
        /// Handle drag start - triggers flip animation and page navigation
        /// </summary>
        public bool OnCardDragStarted(CardContext context)
        {
            if (_isFlipping) return true; // Already handling
            
            // IMPORTANT: Data must be assigned by event listeners (AlbumViewPage) BEFORE we flip
            // The event system guarantees this because events are synchronous
            if (context.CardData == null)
            {
                Logging.Warning("[CardPendingFaceDownState] OnCardDragStarted called but no CardData assigned yet!");
                return true; // Don't flip without data
            }
            
            // Start flip animation (data is now guaranteed to be assigned)
            StartFlipAnimation();
            return true; // We handled it, prevent default DraggingState transition
        }
        
        /// <summary>
        /// We don't handle drag end in face-down state
        /// </summary>
        public bool OnCardDragEnded(CardContext context)
        {
            return false;
        }
        
        private void StartFlipAnimation()
        {
            _isFlipping = true;
            
            // Scale up from corner size to normal dragging size
            if (_context.Animator != null)
            {
                _context.Animator.AnimateScale(_context.OriginalScale * 1.15f, 0.3f);
            }
            
            // Play flip animation
            if (_context.Animator != null)
            {
                _context.Animator.PlayFlip(
                    cardBack: cardBackVisual != null ? cardBackVisual.transform : null,
                    cardFront: _context.CardDisplay != null ? _context.CardDisplay.transform : null,
                    onComplete: OnFlipComplete
                );
            }
            else
            {
                // No animator, just switch visibility immediately
                if (cardBackVisual != null) cardBackVisual.SetActive(false);
                if (_context.CardDisplay != null) _context.CardDisplay.gameObject.SetActive(true);
                OnFlipComplete();
            }
        }
        
        private void OnFlipComplete()
        {
            // Transition to dragging revealed state
            _context.StateMachine.ChangeState("DraggingRevealedState");
        }
        
        private void OnDisable()
        {
            // Hide card back when leaving state
            if (cardBackVisual != null)
            {
                cardBackVisual.SetActive(false);
            }
        }
    }
}