using System;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;
using TMPro;
using BaseGames.Core;
using BaseGames.Core.Events;
using BaseGames.Core.Save;

namespace BaseGames.World.Map
{
    /// <summary>房间可见性三级状态：未知 / 已踏入 / 已标注（购买地图碎片）。</summary>
    public enum RoomVisibility { Unknown, Explored, Mapped }

    /// <summary>
    /// 全屏地图 UI 面板（架构 15_MapShopModule §1.3）。
    /// 由 UIManager PanelStack 管理开关；OnEnable 时重建格子并订阅更新事件。
    /// </summary>
    public class MapPanel : MonoBehaviour
    {
        [SerializeField] private MapDatabaseSO  _database;
        [SerializeField] private RectTransform  _roomContainer;         // 格子图放置根节点
        [SerializeField] private MapRoomCellUI  _cellPrefab;            // 地图格子预制
        [SerializeField] private Image          _exitConnectorPrefab;   // 出口连接线预制（小矩形 Image）
        [SerializeField] private ScrollRect     _scrollRect;            // 包裹 _roomContainer 的滚动矩形（可空，无滚动时留空）

        [Header("图标 Sprites")]
        [SerializeField] private Sprite _iconSavePoint;
        [SerializeField] private Sprite _iconBossRoom;
        [SerializeField] private Sprite _iconShop;
        [SerializeField] private Sprite _iconPlayerPos;

        [Header("颜色")]
        [SerializeField] private Color _colorExplored = Color.white;
        [SerializeField] private Color _colorMapped   = new Color(0.45f, 0.45f, 0.45f, 1f);
        [SerializeField] private Color _colorUnknown  = Color.black;

        [Header("玩家位置")]
        [SerializeField] private MapPlayerTracker _playerTracker;   // 挂在 Player 上的追踪器
        [SerializeField] private Image            _playerIconImg;   // _roomContainer 内的玩家图标

        [Header("地图标记")]
        [SerializeField] private Image            _pinPrefab;
        [SerializeField] private PinSpriteEntry[] _pinSprites;      // PinType → 对应 Sprite
        [SerializeField] private MapPinManager    _pinManager;

        [Header("Tooltip")]
        [SerializeField] private GameObject _tooltipPanel;
        [SerializeField] private TMP_Text   _tooltipText;

        [Header("Event Channels")]
        [SerializeField] private StringEventChannelSO _onMapUpdated;   // 房间发现/标注时刷新

        private Dictionary<string, MapRoomCellUI> _cells             = new();
        private List<Image>                       _pinImages         = new();
        private List<Image>                       _exitImages        = new();
        private string                            _highlightedRoomId;
        private IMapService                       _mapSvc;            // 面板活跃期间缓存，避免高频 ServiceLocator 查询
        private readonly CompositeDisposable      _subs              = new();

        private void OnEnable()
        {
            _mapSvc = ServiceLocator.GetOrDefault<IMapService>();

            // 首次打开时建立格子；后续打开只刷新探索状态，跳过重复 Instantiate
            if (_cells.Count == 0)
                BuildGrid();
            else
                RefreshAllCells();

            RenderPins();
            UpdatePlayerIcon();
            CenterOnCurrentRoom();
            _onMapUpdated?.Subscribe(OnMapUpdated).AddTo(_subs);
        }

        private void OnDisable()
        {
            _subs.Clear();
            _mapSvc = null;
            HideTooltip();
        }

        private void OnDestroy()
        {
            foreach (var cell in _cells.Values)
                if (cell != null) Destroy(cell.gameObject);
            _cells.Clear();
            ClearPins();
            ClearExits();
        }

        private void LateUpdate()
        {
            UpdatePlayerIcon();
        }

        // 面板重新打开时同步关闭期间积累的探索进度
        private void RefreshAllCells()
        {
            foreach (var (roomId, cell) in _cells)
            {
                if (cell == null) continue;
                cell.SetVisibility(GetVisibility(_mapSvc, roomId));
            }
        }

        // ── 格子 & 出口连接 ──────────────────────────────────────────────────

        private void BuildGrid()
        {
            if (_database?.AllRooms == null) return;
            foreach (var room in _database.AllRooms)
            {
                if (room == null) continue;
                var cell = Instantiate(_cellPrefab, _roomContainer);
                cell.Setup(room, GetVisibility(_mapSvc, room.RoomId), ChooseIcon(room),
                    ShowTooltip, HideTooltip);
                _cells[room.RoomId] = cell;
            }
            DrawExits();
        }

        /// <summary>为每条出口在格子坐标处实例化一个小矩形连接线图像。</summary>
        private void DrawExits()
        {
            if (_exitConnectorPrefab == null || _database?.AllRooms == null) return;
            ClearExits();
            const float px = 32f;
            foreach (var room in _database.AllRooms)
            {
                if (room?.Exits == null) continue;
                foreach (var exit in room.Exits)
                {
                    var conn = Instantiate(_exitConnectorPrefab, _roomContainer);
                    conn.rectTransform.anchoredPosition = new Vector2(exit.ExitGridPos.x * px, exit.ExitGridPos.y * px);
                    bool vertical = exit.Direction == ExitDirection.Up || exit.Direction == ExitDirection.Down;
                    conn.rectTransform.sizeDelta = vertical ? new Vector2(16f, 8f) : new Vector2(8f, 16f);
                    _exitImages.Add(conn);
                }
            }
        }

        private void ClearExits()
        {
            foreach (var img in _exitImages)
                if (img != null) Destroy(img.gameObject);
            _exitImages.Clear();
        }

        private void OnMapUpdated(string roomId)
        {
            if (_cells.TryGetValue(roomId, out var cell))
                cell.SetVisibility(GetVisibility(_mapSvc, roomId));
        }

        // ── 玩家位置图标 ──────────────────────────────────────────────────────

        private void UpdatePlayerIcon()
        {
            if (_playerIconImg == null || _playerTracker == null) return;
            var roomId = _playerTracker.CurrentRoomId;
            if (string.IsNullOrEmpty(roomId) || !_cells.TryGetValue(roomId, out var cell))
            {
                _playerIconImg.enabled = false;
                UpdateCellHighlight(null);
                return;
            }
            var cellRT = cell.GetComponent<RectTransform>();
            _playerIconImg.sprite  = _iconPlayerPos;
            _playerIconImg.enabled = true;
            _playerIconImg.rectTransform.anchoredPosition =
                cellRT.anchoredPosition
                + Vector2.Scale(_playerTracker.NormalizedPositionInRoom, cellRT.sizeDelta);
            UpdateCellHighlight(roomId);
        }
        // ── 当前房间高亮 & ScrollRect 居中 ──────────────────────────────────────

        /// <summary>切换高亮描边：取消旧房间高亮，激活新房间高亮。</summary>
        private void UpdateCellHighlight(string roomId)
        {
            if (roomId == _highlightedRoomId) return;
            if (_highlightedRoomId != null && _cells.TryGetValue(_highlightedRoomId, out var prev))
                prev.SetHighlight(false);
            _highlightedRoomId = roomId;
            if (roomId != null && _cells.TryGetValue(roomId, out var next))
                next.SetHighlight(true);
        }

        /// <summary>面板打开时将 ScrollRect 视口居中到玩家当前所在房间。</summary>
        private void CenterOnCurrentRoom()
        {
            if (_scrollRect == null || _playerTracker == null) return;
            var roomId = _playerTracker.CurrentRoomId;
            if (string.IsNullOrEmpty(roomId) || !_cells.TryGetValue(roomId, out var cell)) return;

            Canvas.ForceUpdateCanvases();

            var content  = _scrollRect.content;
            var viewport = _scrollRect.viewport != null
                             ? _scrollRect.viewport
                             : (RectTransform)_scrollRect.transform;
            var cellRT   = cell.GetComponent<RectTransform>();

            // 将 cell 中心转换到 content 本地坐标系
            Vector2 cellWorldCenter = cellRT.TransformPoint(cellRT.rect.center);
            Vector2 cellLocal       = content.InverseTransformPoint(cellWorldCenter);

            // 距 content 左下角的距离（pivot 无关）
            float cellX = cellLocal.x - content.rect.xMin;
            float cellY = cellLocal.y - content.rect.yMin;

            Vector2 viewSize    = viewport.rect.size;
            Vector2 contentSize = content.rect.size;
            float   rangeX      = contentSize.x - viewSize.x;
            float   rangeY      = contentSize.y - viewSize.y;

            float normX = rangeX > 0 ? Mathf.Clamp01((cellX - viewSize.x * 0.5f) / rangeX) : 0.5f;
            float normY = rangeY > 0 ? Mathf.Clamp01((cellY - viewSize.y * 0.5f) / rangeY) : 0.5f;

            _scrollRect.normalizedPosition = new Vector2(normX, normY);
        }
        // ── 地图标记渲染 ──────────────────────────────────────────────────────

        private void RenderPins()
        {
            ClearPins();
            if (_pinPrefab == null || _pinManager == null) return;
            foreach (var pin in _pinManager.Pins)
            {
                if (!_cells.TryGetValue(pin.RoomId, out var cell)) continue;
                var img    = Instantiate(_pinPrefab, _roomContainer);
                img.sprite = GetPinSprite((PinType)pin.PinTypeInt);
                var cellRT = cell.GetComponent<RectTransform>();
                img.rectTransform.anchoredPosition =
                    cellRT.anchoredPosition + new Vector2(
                        pin.NormalizedPosX * cellRT.sizeDelta.x,
                        pin.NormalizedPosY * cellRT.sizeDelta.y);
                _pinImages.Add(img);
            }
        }

        private void ClearPins()
        {
            foreach (var img in _pinImages)
                if (img != null) Destroy(img.gameObject);
            _pinImages.Clear();
        }

        // ── Tooltip ───────────────────────────────────────────────────────────

        private void ShowTooltip(string text)
        {
            if (_tooltipPanel == null || string.IsNullOrEmpty(text)) return;
            if (_tooltipText != null) _tooltipText.text = text;
            _tooltipPanel.SetActive(true);
        }

        private void HideTooltip() => _tooltipPanel?.SetActive(false);

        // ── 辅助方法 ──────────────────────────────────────────────────────────

        /// <summary>按优先级推导可见性：Explored > Mapped > Unknown。</summary>
        private static RoomVisibility GetVisibility(IMapService svc, string roomId)
        {
            if (svc == null) return RoomVisibility.Unknown;
            if (svc.IsExplored(roomId)) return RoomVisibility.Explored;
            if (svc.IsMapped(roomId))   return RoomVisibility.Mapped;
            return RoomVisibility.Unknown;
        }

        private Sprite ChooseIcon(MapRoomDataSO room)
        {
            if (room.MapIconOverride != null) return room.MapIconOverride;
            if (room.IsSavePoint) return _iconSavePoint;
            if (room.IsBossRoom)  return _iconBossRoom;
            if (room.IsShop)      return _iconShop;
            return null;
        }

        private Sprite GetPinSprite(PinType type)
        {
            if (_pinSprites != null)
                foreach (var e in _pinSprites)
                    if (e.PinType == type) return e.Sprite;
            return null;
        }
    }

    [Serializable]
    public struct PinSpriteEntry
    {
        public PinType PinType;
        public Sprite  Sprite;
    }

    // ─── 单个地图格子 UI ─────────────────────────────────────────────────────────

    /// <summary>地图面板中每个房间对应的格子 UI 组件。</summary>
    public class MapRoomCellUI : MonoBehaviour, IPointerEnterHandler, IPointerExitHandler
    {
        [SerializeField] private Image    _bg;
        [SerializeField] private Image    _icon;
        [SerializeField] private RawImage _outlineImage;  // 可选：房间非矩形轮廓纹理
        [SerializeField] private Image    _highlight;     // 可选：当前房间高亮描边（玩家所在时激活）

        private static readonly Color ColExplored = Color.white;
        private static readonly Color ColMapped   = new Color(0.45f, 0.45f, 0.45f, 1f);
        private static readonly Color ColUnknown  = Color.black;

        private string         _displayName;
        private Action<string> _onHover;
        private Action         _onHoverExit;

        /// <summary>初始化格子（位置、可见性、图标、Tooltip 回调）。</summary>
        public void Setup(MapRoomDataSO room, RoomVisibility visibility, Sprite icon,
                          Action<string> onHover = null, Action onHoverExit = null)
        {
            _displayName = room.DisplayName;
            _onHover     = onHover;
            _onHoverExit = onHoverExit;

            if (TryGetComponent<RectTransform>(out var rt))
            {
                rt.anchoredPosition = new Vector2(room.GridPosition.x * 32f, room.GridPosition.y * 32f);
                rt.sizeDelta        = new Vector2(room.GridSize.x * 32f,     room.GridSize.y * 32f);
            }

            // 房间轮廓纹理（非矩形形状，覆盖在矩形背景上方）
            if (_outlineImage != null)
            {
                _outlineImage.texture = room.RoomOutlineTex;
                _outlineImage.enabled = room.RoomOutlineTex != null;
            }

            SetVisibility(visibility);

            if (_icon != null)
            {
                _icon.sprite  = icon;
                _icon.enabled = icon != null;
            }
        }

        public void SetVisibility(RoomVisibility v)
        {
            if (_bg == null) return;
            _bg.color = v switch
            {
                RoomVisibility.Explored => ColExplored,
                RoomVisibility.Mapped   => ColMapped,
                _                       => ColUnknown,
            };
        }

        /// <summary>向后兼容：直接传 bool 时等同于 Explored / Unknown。</summary>
        public void SetDiscovered(bool v)
            => SetVisibility(v ? RoomVisibility.Explored : RoomVisibility.Unknown);

        /// <summary>激活/取消当前房间高亮描边。</summary>
        public void SetHighlight(bool v)
        {
            if (_highlight != null) _highlight.enabled = v;
        }

        public void OnPointerEnter(PointerEventData _)
        {
            if (!string.IsNullOrEmpty(_displayName)) _onHover?.Invoke(_displayName);
        }

        public void OnPointerExit(PointerEventData _) => _onHoverExit?.Invoke();
    }
}