using System.Collections.Generic;
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：左滑时内容元素向左滑出，露出右侧菜单，
    /// 滑动超过菜单宽度1/3松手则完整展开，否则缩回
    /// </summary>
    public class HomePageDeviceItem : MonoBehaviour, IBeginDragHandler, IDragHandler, IEndDragHandler
    {
        public Text deviceNameText;
        /// <summary>
        /// 置顶标识
        /// </summary>
        public GameObject topIcon;
        public GameObject selectedIndicator;
        /// <summary>菜单（子物体，锚点位于item最右侧），内容左移后露出</summary>
        public RectTransform menuRect;

        // 当前设备信息
        public DeviceInfo deviceInfo;
        /// <summary>
        /// 菜单按钮数组 0：重命名 1：分享 2：删除 3：置顶 4：取消置顶
        /// 最多显示3个按钮 拥有的设备显示分享 被分享的设备显示删除
        /// 根据置顶状态显示置顶/取消置顶按钮
        /// </summary>
        public Button[] menuButtons;
        /// <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;
        private bool menuListenersBound;
        /// <summary>除菜单外的内容子物体</summary>
        private readonly List<RectTransform> contentRects = new List<RectTransform>();
        /// <summary>各内容子物体的初始位置</summary>
        private readonly List<Vector2> contentInitPositions = new List<Vector2>();

        void Awake()
        {
            button = GetComponent<Button>();
            // 点击item主体：关闭其他item展开的菜单，同时收起自己的
            if (button != null)
                button.onClick.AddListener(OnItemClicked);
            InitSwipe();
        }

        /// <summary>
        /// item主体点击：全局仅保留一个菜单，点击任意item时关闭其他item的展开菜单
        /// </summary>
        private void OnItemClicked()
        {
            if (openItem != null && openItem != this)
                openItem.CloseMenu();
            CloseMenu();
        }

        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, bool isOwner)
        {
            deviceInfo = device;
            deviceNameText.text = device.device_name;
            selectedIndicator.SetActive(false);
            if (topIcon != null) topIcon.SetActive(device.is_top);
            SetupMenuButtons(isOwner);
            BindMenuButtonClose();
            InitSwipe();
        }

        /// <summary>
        /// 根据设备归属和置顶状态显示/隐藏菜单按钮
        /// 0重命名 1分享 2删除 3置顶 4取消置顶
        /// 拥有者：重命名+分享+置顶/取消置顶；被分享者：删除+置顶/取消置顶
        /// </summary>
        private void SetupMenuButtons(bool isOwner)
        {
            if (menuButtons == null || menuButtons.Length < 5) return;
            menuButtons[0].gameObject.SetActive(true);            // 重命名仅拥有者
            menuButtons[1].gameObject.SetActive(isOwner);            // 分享仅拥有者
            menuButtons[2].gameObject.SetActive(!isOwner);           // 删除（移除共享）仅被分享者
            menuButtons[3].gameObject.SetActive(!deviceInfo.is_top); // 置顶：未置顶时显示
            menuButtons[4].gameObject.SetActive(deviceInfo.is_top);  // 取消置顶：已置顶时显示
        }

        /// <summary>
        /// 点击菜单内任意按钮时自动收起菜单
        /// </summary>
        private void BindMenuButtonClose()
        {
            if (menuListenersBound || menuRect == null) return;
            menuListenersBound = true;
            foreach (var b in menuRect.GetComponentsInChildren<Button>(true))
                b.onClick.AddListener(CloseMenu);
        }

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

        /// <summary>
        /// 初始化滑动数据：收集内容子物体、记录初始位置，重置为收起状态
        /// </summary>
        private void InitSwipe()
        {
            tweener?.Kill();
            if (menuRect == null) return;
            // 先复位已记录的内容，再重新收集（兼容item复用）
            ApplyOffset(0);
            contentRects.Clear();
            contentInitPositions.Clear();
            foreach (Transform child in transform)
            {
                if (child == menuRect) continue;
                RectTransform rt = child as RectTransform;
                if (rt == null) continue;
                contentRects.Add(rt);
                contentInitPositions.Add(rt.anchoredPosition);
            }
            menuWidth = menuRect.sizeDelta.x;
            menuInitPos = menuRect.anchoredPosition3D;
            isMenuOpen = false;
            currentOffset = 0;
            ApplyOffset(0);
        }

        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;
            currentOffset = isMenuOpen ? -menuWidth : 0;
            dragStartOffset = currentOffset;
            ApplyOffset(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);
            ApplyOffset(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>
        /// 将内容子物体和菜单一起平移到指定偏移（内容左移、菜单从屏幕外滑入露出）
        /// </summary>
        private void ApplyOffset(float offset)
        {
            for (int i = 0; i < contentRects.Count; i++)
            {
                Vector2 pos = contentInitPositions[i];
                pos.x += offset;
                contentRects[i].anchoredPosition = pos;
            }
            Vector3 menuPos = menuInitPos;
            menuPos.x += offset;
            menuRect.anchoredPosition3D = menuPos;
        }

        /// <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;
            tweener = DOTween.To(() => currentOffset, v =>
            {
                currentOffset = v;
                ApplyOffset(v);
            }, target, 0.25f).SetEase(Ease.OutCubic);
        }
    }
}