using DG.Tweening;
using Kill.Managers;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;

namespace Kill.UI.Pages
{
    /// <summary>
    /// 首页设备列表项 - 显示单个设备信息
    /// 支持左滑手势：左滑时菜单向左滑出并显示高斯模糊覆盖层，
    /// 滑动超过菜单宽度1/3松手则完整展开，否则缩回并隐藏模糊层
    /// </summary>
    public class HomePageDeviceItem : MonoBehaviour, IBeginDragHandler, IDragHandler, IEndDragHandler
    {
        public Text deviceNameText;
        public GameObject selectedIndicator;
        /// <summary>菜单（子物体，锚点位于item最右侧），左滑时向左滑出</summary>
        public RectTransform menuRect;
        /// <summary>高斯模糊覆盖层（子物体，覆盖其他内容），菜单出现时显示，缩回时隐藏</summary>
        public GameObject blurOverlay;

        // 当前设备信息
        public DeviceInfo deviceInfo;

        /// <summary>当前展开菜单的item（全局仅允许一个菜单展开）</summary>
        private static HomePageDeviceItem openItem;

        private float menuWidth;
        private float currentOffset;
        private float dragStartOffset;
        private bool isMenuOpen;
        private bool isDragging;
        private Vector3 menuInitPos;
        private Tweener tweener;
        private Button button;

        void Awake()
        {
            button = GetComponent<Button>();
            InitSwipe();
        }

        void OnDisable()
        {
            // 防止拖拽中被禁用且未恢复的情况
            if (button != null) button.interactable = true;
        }

        void OnDestroy()
        {
            // 销毁时释放全局展开引用
            if (openItem == this)
                openItem = null;
        }

        public void InitDeviceItem(DeviceInfo device)
        {
            deviceInfo = device;
            deviceNameText.text = device.device_name;
            selectedIndicator.SetActive(false);
            InitSwipe();
        }

        public void SetSelectedState(bool isSelected)
        {
            // 设置选中状态
            selectedIndicator.SetActive(isSelected);
        }

        /// <summary>
        /// 初始化滑动数据：记录菜单初始位置、菜单宽度，重置为收起状态
        /// </summary>
        private void InitSwipe()
        {
            tweener?.Kill();
            if (menuRect == null) return;
            menuWidth = menuRect.sizeDelta.x;
            menuInitPos = menuRect.anchoredPosition3D;
            isMenuOpen = false;
            currentOffset = 0;
            ApplyMenuOffset(0);
            if (blurOverlay != null) blurOverlay.SetActive(false);
        }

        public void OnBeginDrag(PointerEventData eventData)
        {
            if (menuRect == null || menuWidth <= 0) return;
            // 拖拽滑动时禁用按钮点击，避免与菜单滑动同时触发
            if (button != null) button.interactable = false;
            // 其他item的菜单展开时，先收起，保证全局只有一个菜单
            if (openItem != null && openItem != this)
                openItem.CloseMenu();
            isDragging = true;
            // 菜单开始出现，显示高斯模糊覆盖层
            if (blurOverlay != null) blurOverlay.SetActive(true);
            currentOffset = isMenuOpen ? -menuWidth : 0;
            dragStartOffset = currentOffset;
            ApplyMenuOffset(currentOffset);
        }

        public void OnDrag(PointerEventData eventData)
        {
            if (!isDragging) return;
            // 累加位移并限制在 [-菜单宽度, 0]，只允许左滑露出菜单
            currentOffset += eventData.delta.x;
            currentOffset = Mathf.Clamp(currentOffset, -menuWidth, 0);
            ApplyMenuOffset(currentOffset);
        }

        public void OnEndDrag(PointerEventData eventData)
        {
            if (!isDragging) return;
            isDragging = false;
            // 恢复按钮点击
            if (button != null) button.interactable = true;
            // 右滑超过菜单宽度的1/5则直接缩回（方便关闭已展开的菜单）
            float dragDistance = currentOffset - dragStartOffset;
            if (dragDistance > menuWidth / 5f)
            {
                AnimateTo(0);
                return;
            }
            // 左滑展示超过菜单宽度的1/3则完整滑出，否则缩回
            float target = currentOffset < -menuWidth / 3f ? -menuWidth : 0;
            AnimateTo(target);
        }

        /// <summary>
        /// 收起菜单（供菜单按钮点击等外部调用）
        /// </summary>
        public void CloseMenu()
        {
            if (!isMenuOpen) return;
            AnimateTo(0);
        }

        /// <summary>
        /// 将菜单平移到指定偏移
        /// </summary>
        private void ApplyMenuOffset(float offset)
        {
            Vector3 pos = menuInitPos;
            pos.x += offset;
            menuRect.anchoredPosition3D = pos;
        }

        /// <summary>
        /// 平滑动画到目标偏移
        /// </summary>
        private void AnimateTo(float target)
        {
            tweener?.Kill();
            bool open = target < 0;
            if (open)
            {
                // 已有其他item的菜单展开时，先收起，保证全局只有一个菜单
                if (openItem != null && openItem != this)
                    openItem.CloseMenu();
                openItem = this;
            }
            else if (openItem == this)
            {
                openItem = null;
            }
            isMenuOpen = open;
            if (!isMenuOpen && blurOverlay != null)
                blurOverlay.SetActive(false); // 菜单缩回时隐藏模糊层
            tweener = DOTween.To(() => currentOffset, v =>
            {
                currentOffset = v;
                ApplyMenuOffset(v);
            }, target, 0.25f).SetEase(Ease.OutCubic);
        }
    }
}