using System;
using System.Collections;
using System.Linq;
using AibisDream.Framework;
using DG.Tweening;
using UnityEngine;
using UnityEngine.EventSystems;

namespace AibisDream.MiniGame.Tarot
{
    public enum TarotOrientation
    {
        Normal,
        Inverted
    }

    [RequireComponent(typeof(SpriteRenderer))]
    [RequireComponent(typeof(BoxCollider2D))]
    public class TarotCard : MonoBehaviour, IInteraction
    {
        #region IInteraction

        public bool IsActive => _isInteractable;
        public bool IsAvailable => _isInteractable;
        public GameObject GetGameObject() => gameObject;

        #endregion

        #region Public State

        public bool IsFaceUp { get; private set; }
        public TarotOrientation Orientation { get; private set; } = TarotOrientation.Normal;
        public int Index { get; private set; }

        #endregion

        #region Events

        public Action OnHoverEnter;
        public Action OnHoverExit;
        /// <summary>PointerDown（按下时触发；点击确认由 TarotDeck 在 MouseButtonUp 时统一处理，避免 hover 位移动导致 PointerExit 阻断 PointerClick）</summary>
        public Action OnPointerDown;

        #endregion

        private SpriteRenderer _spriteRenderer;
        private EventTriggerEx _eventTrigger;
        private Sprite _frontSprite;
        private Sprite _backSprite;
        private bool _isInteractable;
        private Tweener _flipTween;
        private Tweener _orientationTween;

        public void Init(int index, Sprite frontSprite, Sprite backSprite)
        {
            Index = index;
            _spriteRenderer = GetComponent<SpriteRenderer>();
            // 运行时若 TarotManager 未拖入 Sprite，不要用 null 覆盖预制体上的图，否则牌会完全消失
            _frontSprite = frontSprite;
            _backSprite = backSprite != null ? backSprite : _spriteRenderer.sprite;
            if (backSprite != null)
                _spriteRenderer.sprite = backSprite;
            else if (_spriteRenderer.sprite == null)
                Debug.LogWarning("[TarotCard] 背面与预制体均无 Sprite，牌将不可见。请在 TarotManager 上指定 Back / Front Sprite。", this);

            IsFaceUp = false;
            Orientation = TarotOrientation.Normal;
            transform.localScale = Vector3.one;
            transform.localRotation = Quaternion.identity;
        }

        private void Awake()
        {
            _spriteRenderer = GetComponent<SpriteRenderer>();
            SetupEventTrigger();
        }

        private void OnDestroy()
        {
            if (_eventTrigger != null)
            {
                _eventTrigger.UnRegister(EventTriggerType.PointerEnter, HandlePointerEnter);
                _eventTrigger.UnRegister(EventTriggerType.PointerExit, HandlePointerExit);
                _eventTrigger.UnRegister(EventTriggerType.PointerDown, HandlePointerDown);
            }

            _flipTween?.Kill();
            _orientationTween?.Kill();
        }

        #region EventTriggerEx Setup

        private void SetupEventTrigger()
        {
            _eventTrigger = GetComponent<EventTriggerEx>();
            if (_eventTrigger == null)
            {
                _eventTrigger = gameObject.AddComponent<EventTriggerEx>();
            }

            EnsureEventTriggerEntries();
            _eventTrigger.Register(EventTriggerType.PointerEnter, HandlePointerEnter);
            _eventTrigger.Register(EventTriggerType.PointerExit, HandlePointerExit);
            _eventTrigger.Register(EventTriggerType.PointerDown, HandlePointerDown);
        }

        private void EnsureEventTriggerEntries()
        {
            if (_eventTrigger == null) return;
            var triggers = _eventTrigger.triggers;
            var needed = new[]
            {
                EventTriggerType.PointerEnter,
                EventTriggerType.PointerExit,
                EventTriggerType.PointerDown
            };
            foreach (var t in needed)
            {
                if (triggers.Any(e => e.eventID == t)) continue;
                triggers.Add(new EventTrigger.Entry { eventID = t });
            }
        }

        private void HandlePointerEnter(BaseEventData data)
        {
            if (!_isInteractable) return;
            OnHoverEnter?.Invoke();
        }

        private void HandlePointerExit(BaseEventData data)
        {
            if (!_isInteractable) return;
            OnHoverExit?.Invoke();
        }

        private void HandlePointerDown(BaseEventData data)
        {
            if (!_isInteractable) return;
            OnPointerDown?.Invoke();
        }

        #endregion

        #region Public API

        public void SetInteractable(bool interactable)
        {
            _isInteractable = interactable;
        }

        /// <summary>
        /// Flip the card to reveal front side with a target orientation.
        /// X-scale: 1 -> 0 (swap sprite) -> 1, then apply orientation via local Z rotation (0° / 180°).
        /// </summary>
        public IEnumerator Flip(TarotOrientation targetOrientation, float duration = 0.5f)
        {
            _flipTween?.Kill();
            _orientationTween?.Kill();
            float half = duration * 0.5f;
            var scale = transform.localScale;

            var seq = DOTween.Sequence();
            seq.Append(transform.DOScaleX(0f, half).SetEase(Ease.InQuad));
            seq.AppendCallback(() =>
            {
                IsFaceUp = !IsFaceUp;
                var next = IsFaceUp ? _frontSprite : _backSprite;
                if (next != null)
                    _spriteRenderer.sprite = next;
                else if (IsFaceUp)
                    Debug.LogWarning("[TarotCard] Front Sprite 未设置，翻牌后无法显示正面。", this);

                ApplyOrientationToTransform(targetOrientation);
            });
            seq.Append(transform.DOScaleX(scale.x, half).SetEase(Ease.OutQuad));

            yield return seq.WaitForCompletion();
        }

        /// <summary>
        /// Change orientation of an already face-up card (rotate 180 degrees around local Z).
        /// 结束后与翻牌一致：用本地 Z 旋转表示逆位，避免动画末尾用负 scale.y 与 Rz(180°) 不等价造成镜像闪变。
        /// </summary>
        public IEnumerator SetOrientationAnimated(TarotOrientation targetOrientation, float duration = 0.7f)
        {
            if (Orientation == targetOrientation) yield break;

            _flipTween?.Kill();
            _orientationTween?.Kill();

            // 旧版用负 scale.y 表示逆位时，收束为绕本地 Z 再转 180°，避免与后续 Rz 动画叠加错乱
            EnsureOrientationUsesRotationNotNegativeScale();

            // 使用本地旋转，避免 DORotate（世界欧拉）与 localEulerAngles 混用导致几乎不转或乱跳
            var endLocal = transform.localRotation * Quaternion.Euler(0f, 0f, 180f);
            _orientationTween = transform.DOLocalRotateQuaternion(endLocal, duration)
                .SetEase(Ease.InOutSine);

            yield return _orientationTween.WaitForCompletion();
            _orientationTween = null;

            ApplyOrientationToTransform(targetOrientation);
        }

        public void SetOrientationImmediate(TarotOrientation orientation)
        {
            ApplyOrientationToTransform(orientation);
        }

        /// <summary>正立/逆位统一用本地 Z（0° / 180°），scale.y 恒为正。</summary>
        private void ApplyOrientationToTransform(TarotOrientation orientation)
        {
            Orientation = orientation;
            transform.localRotation = Quaternion.Euler(0f, 0f, orientation == TarotOrientation.Inverted ? 180f : 0f);
            var s = transform.localScale;
            s.y = Mathf.Abs(s.y);
            transform.localScale = s;
        }

        /// <summary>仅处理旧版负 scale.y：改为正 scale 并在本地绕 Z 补 180°，不覆盖扇形等已有 localRotation。</summary>
        private void EnsureOrientationUsesRotationNotNegativeScale()
        {
            var s = transform.localScale;
            if (s.y >= 0f) return;
            s.y = Mathf.Abs(s.y);
            transform.localScale = s;
            transform.localRotation = transform.localRotation * Quaternion.Euler(0f, 0f, 180f);
        }

        public void SetAlpha(float alpha)
        {
            if (_spriteRenderer == null) _spriteRenderer = GetComponent<SpriteRenderer>();
            var c = _spriteRenderer.color;
            c.a = alpha;
            _spriteRenderer.color = c;
        }

        public Tweener DOFade(float target, float duration)
        {
            return _spriteRenderer.DOFade(target, duration);
        }

        public void SetSortingOrder(int order)
        {
            if (_spriteRenderer == null) _spriteRenderer = GetComponent<SpriteRenderer>();
            _spriteRenderer.sortingOrder = order;
        }

        #endregion
    }
}