using System;
using System.Collections.Generic;
using System.Linq;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.InputSystem;
using Vanguard.Shared.Protocol;

namespace Vanguard.Board3D
{
    /// <summary>
    /// 3D-поле: стол, круги, общий круг защиты, стопки, веер руки и карты.
    /// Отрисовка полностью процедурная; материалы и меши переиспользуются.
    /// </summary>
    public sealed class GameBoard3D : MonoBehaviour
    {
        private const string RootName = "GameBoard3D";

        private static GameBoard3D _instance;

        private readonly List<BoardSlotView> _slots = new List<BoardSlotView>();
        private readonly Dictionary<BoardSlotKey, BoardSlotView> _slotByKey =
            new Dictionary<BoardSlotKey, BoardSlotView>();
        private readonly Dictionary<string, Card3D> _cards =
            new Dictionary<string, Card3D>(StringComparer.Ordinal);
        private readonly Stack<Card3D> _pool = new Stack<Card3D>();
        private readonly List<Pile3D> _piles = new List<Pile3D>();
        private readonly BoardZoneView[] _damageZones = new BoardZoneView[2];
        private readonly HashSet<BoardSlotKey> _activeHighlights = new HashSet<BoardSlotKey>();
        private readonly HashSet<BoardSlotKey> _validDropSlots = new HashSet<BoardSlotKey>();
        private readonly List<HandCardBinding> _handBindings = new List<HandCardBinding>();
        private bool _guardianDropAllowed;

        private PlaymatLayoutConfig _config;
        private PlaymatLayout _layout;
        private MatchView _view;
        private int _selfPlayer;
        private bool _hasRendered;
        private bool _built;

        private Transform _slotsRoot;
        private Transform _cardsRoot;
        private Transform _pilesRoot;
        private Transform _zonesRoot;
        private Camera _camera;
        private BoardCameraRig _cameraRig;
        private bool _ownsRig;

        private BoardZoneView _guardianZone;
        private BoardZoneView _dropIndicator;
        private Pile3D _deckSelf;
        private Pile3D _deckOpponent;
        private Pile3D _dropSelf;
        private Pile3D _dropOpponent;
        private Pile3D _soulSelf;
        private Pile3D _soulOpponent;

        private enum PointerMode
        {
            None,
            Card,
            Slot,
            Pile,
        }

        private PointerMode _mode;
        private Card3D _pressedCard;
        private BoardCardRef _pressedCardRef;
        private BoardSlotView _pressedSlot;
        private Pile3D _pressedPile;
        private Vector2 _pressPosition;
        private bool _dragging;
        private BoardDropTarget? _dragTarget;

        public PlaymatLayoutConfig Config => _config;
        public PlaymatLayout Layout => _layout;
        public int SelfPlayer => _selfPlayer;
        public BoardArtProvider ArtProvider { get; set; }

        public event Action<BoardCardRef> CardClicked;
        public event Action<BoardCardRef> SlotClicked;
        public event Action<BoardCardRef, BoardCardRef> CardDropped;
        public event Action<BoardCardRef> PileClicked;

        public static GameBoard3D Create(Transform parent, PlaymatLayoutConfig config = null)
        {
            if (_instance != null)
            {
                var previous = _instance.gameObject;
                if (Application.isPlaying)
                    Destroy(previous);
                else
                    DestroyImmediate(previous);
            }

            var go = new GameObject(RootName);
            if (parent != null)
                go.transform.SetParent(parent, false);

            var board = go.AddComponent<GameBoard3D>();
            board.Initialize(config);
            _instance = board;
            return board;
        }

        public void Initialize(PlaymatLayoutConfig config)
        {
            if (_built)
                return;

            _config = config != null ? config : PlaymatLayoutConfig.Default;
            _layout = new PlaymatLayout(_config);
            _selfPlayer = 0;
            _built = true;

            BuildTable();
            BuildSlots();
            BuildZones();
            BuildPiles();
            BuildDropIndicator();

            _cardsRoot = new GameObject("Cards").transform;
            _cardsRoot.SetParent(transform, false);

            EnsureCamera();
            SetVisible(false);
        }

        public void SetSelfPlayer(int player)
        {
            player = player == 0 ? 0 : 1;
            if (_selfPlayer == player)
                return;

            _selfPlayer = player;
            foreach (var slot in _slots)
                slot.SetPlayer(LocalToPlayer(slot.LocalSeat));

            _deckSelf.SetPlayer(LocalToPlayer(0));
            _dropSelf.SetPlayer(LocalToPlayer(0));
            _soulSelf.SetPlayer(LocalToPlayer(0));
            _deckOpponent.SetPlayer(LocalToPlayer(1));
            _dropOpponent.SetPlayer(LocalToPlayer(1));
            _soulOpponent.SetPlayer(LocalToPlayer(1));
            _hasRendered = false;
        }

        public void SetVisible(bool visible)
        {
            if (!visible)
            {
                CancelPointer();
                _hasRendered = false;
                _handBindings.Clear();
            }
            else
            {
                EnsureCamera();
            }

            gameObject.SetActive(visible);
            if (_cameraRig != null)
                _cameraRig.enabled = visible;
        }

        public void Render(MatchView view, BoardRenderState state)
        {
            if (!_built)
                return;

            if (view == null)
            {
                ClearCards();
                _view = null;
                return;
            }

            SetSelfPlayer(view.You);
            _view = view;
            state ??= new BoardRenderState();
            if (_camera == null)
                _camera = Camera.main;

            _handBindings.Clear();
            var specs = new List<CardSpec>(40);
            BuildSpecs(view, state, specs);

            var used = new HashSet<string>(StringComparer.Ordinal);
            var immediateAll = !_hasRendered;

            foreach (var spec in specs)
            {
                used.Add(spec.Key);
                if (!_cards.TryGetValue(spec.Key, out var card) || card == null)
                {
                    card = RentCard();
                    _cards[spec.Key] = card;
                }

                var changed = !card.gameObject.activeSelf
                    || card.Ref.InstanceId != spec.Ref.InstanceId
                    || card.Ref.Zone != spec.Ref.Zone;
                card.Bind(spec.Ref);
                card.SetArt(spec.Art.Front, spec.Art.Accent);
                card.SetPose(
                    spec.Position,
                    spec.BaseRotation,
                    spec.FaceUp,
                    spec.Rested,
                    immediateAll || changed,
                    spec.DamageLayout,
                    spec.Scale);
                card.SetHighlight(spec.Highlight);

                if (spec.IsHand)
                {
                    _handBindings.Add(new HandCardBinding(
                        card,
                        spec.HandIndex,
                        spec.HandCount));
                }
            }

            if (_cards.Count > 0)
            {
                var stale = _cards
                    .Where(pair => !used.Contains(pair.Key))
                    .Select(pair => pair.Key)
                    .ToList();
                foreach (var key in stale)
                {
                    ReleaseCard(_cards[key]);
                    _cards.Remove(key);
                }
            }

            UpdatePiles(view);
            UpdateSlots(state);
            _hasRendered = true;
        }

        public void Clear()
        {
            ClearCards();
            _handBindings.Clear();
            _view = null;
            _hasRendered = false;
        }

        private void BuildTable()
        {
            var width = (_config.boardHalfWidth * 2f) + 2.2f;
            var depth = (_config.boardHalfLength * 2f) + 1.7f;
            CreateBox(
                "Table",
                new Vector3(0f, -0.06f, 0f),
                new Vector3(width, 0.12f, depth),
                _config.tableColor);

            var matWidth = (_config.boardHalfWidth * 2f) - 0.45f;
            var matDepth = _config.boardHalfLength - 0.35f;

            CreateBox(
                "Mat Self",
                new Vector3(0f, 0.002f, -(_config.boardHalfLength * 0.5f) - 0.05f),
                new Vector3(matWidth, 0.008f, matDepth),
                _config.matSelfColor);
            CreateBox(
                "Mat Opponent",
                new Vector3(0f, 0.002f, (_config.boardHalfLength * 0.5f) + 0.05f),
                new Vector3(matWidth, 0.008f, matDepth),
                _config.matOpponentColor);

            var divider = BoardMaterials.CreateLit(_config.lineColor, 1.2f);
            CreateBox(
                "Center Line",
                new Vector3(0f, 0.011f, 0f),
                new Vector3(width - 0.3f, 0.012f, 0.055f),
                divider);

            var railMaterial = BoardMaterials.CreateLit(_config.lineColor, 0.9f);
            CreateBox(
                "Rail Left",
                new Vector3(-(_config.boardHalfWidth + 1.02f), 0.04f, 0f),
                new Vector3(0.07f, 0.08f, depth),
                railMaterial);
            CreateBox(
                "Rail Right",
                new Vector3(_config.boardHalfWidth + 1.02f, 0.04f, 0f),
                new Vector3(0.07f, 0.08f, depth),
                railMaterial);
            CreateBox(
                "Rail Near",
                new Vector3(0f, 0.04f, -(_config.boardHalfLength + 0.79f)),
                new Vector3(width, 0.08f, 0.07f),
                railMaterial);
            CreateBox(
                "Rail Far",
                new Vector3(0f, 0.04f, _config.boardHalfLength + 0.79f),
                new Vector3(width, 0.08f, 0.07f),
                railMaterial);
        }

        private void BuildSlots()
        {
            _slotsRoot = new GameObject("Slots").transform;
            _slotsRoot.SetParent(transform, false);

            for (var localSeat = 0; localSeat < 2; localSeat++)
            {
                for (var slot = PlaymatLayout.VanguardSlot;
                     slot < PlaymatLayout.RearGuardCount;
                     slot++)
                {
                    var view = BoardSlotView.Create(
                        _slotsRoot,
                        _config,
                        localSeat,
                        LocalToPlayer(localSeat),
                        slot,
                        _layout);
                    _slots.Add(view);
                    _slotByKey[view.Key] = view;
                }
            }
        }

        private void BuildZones()
        {
            _zonesRoot = new GameObject("Zones").transform;
            _zonesRoot.SetParent(transform, false);

            var guardianDepth = (_config.guardianRowGap * 2f) + 0.8f;
            _guardianZone = BoardZoneView.Create(
                _zonesRoot,
                "Guardian Zone",
                new Vector3(0f, 0.012f, 0f),
                _config.guardianMaxWidth + 1.4f,
                guardianDepth,
                Mathf.Max(0.022f, _config.cardWidth * 0.04f),
                _config.guardianColor,
                "GUARDIAN",
                0.11f,
                -(guardianDepth * 0.5f) - 0.2f,
                new Color(0.72f, 0.92f, 1f, 0.75f),
                _config.highlightColor);

            for (var localSeat = 0; localSeat < 2; localSeat++)
            {
                var zSign = _layout.ZSign(localSeat);
                var sideSign = localSeat == 0 ? -1f : 1f;
                var zone = BoardZoneView.Create(
                    _zonesRoot,
                    "Damage Zone " + localSeat,
                    new Vector3(
                        sideSign * (_config.damageX + 0.02f),
                        0.011f,
                        zSign * (_config.frontRowZ + 1.15f)),
                    1.72f,
                    2.25f,
                    Mathf.Max(0.018f, _config.cardWidth * 0.03f),
                    _config.damageColor,
                    "DAMAGE",
                    0.1f,
                    -zSign * 1.32f,
                    new Color(1f, 0.78f, 0.76f, 0.75f),
                    _config.highlightColor);
                _damageZones[localSeat] = zone;
            }
        }

        private void BuildPiles()
        {
            _pilesRoot = new GameObject("Piles").transform;
            _pilesRoot.SetParent(transform, false);

            _deckSelf = CreatePile(BoardZone.Deck, 0, 0, "DECK", new Color(0.20f, 0.34f, 0.60f));
            _deckOpponent = CreatePile(BoardZone.Deck, 1, 1, "DECK", new Color(0.60f, 0.26f, 0.26f));
            _dropSelf = CreatePile(BoardZone.Drop, 0, 0, "DROP", new Color(0.30f, 0.30f, 0.40f));
            _dropOpponent = CreatePile(BoardZone.Drop, 1, 1, "DROP", new Color(0.40f, 0.28f, 0.28f));
            _soulSelf = CreatePile(BoardZone.Soul, 0, 0, "SOUL", _config.soulColor);
            _soulOpponent = CreatePile(BoardZone.Soul, 1, 1, "SOUL", _config.soulColor);
        }

        private Pile3D CreatePile(
            BoardZone zone,
            int player,
            int localSeat,
            string title,
            Color accent)
        {
            var position = zone switch
            {
                BoardZone.Deck => _layout.DeckPosition(localSeat),
                BoardZone.Drop => _layout.DropPosition(localSeat),
                _ => _layout.SoulPosition(localSeat),
            };

            var pile = Pile3D.Create(
                _pilesRoot,
                _config,
                zone,
                player,
                position,
                title,
                accent);
            _piles.Add(pile);
            return pile;
        }

        private void BuildDropIndicator()
        {
            _dropIndicator = BoardZoneView.Create(
                transform,
                "Drop Indicator",
                new Vector3(0f, 0.014f, 0f),
                _config.cardWidth * 1.4f,
                _config.cardHeight * 1.4f,
                0.025f,
                _config.highlightColor,
                null,
                0.1f,
                0f,
                Color.white,
                _config.selectedColor);
            _dropIndicator.gameObject.SetActive(false);
        }

        private void EnsureCamera()
        {
            if (_camera == null)
                _camera = Camera.main;
            if (_camera == null)
                return;

            if (_cameraRig == null)
            {
                _cameraRig = _camera.GetComponent<BoardCameraRig>();
                if (_cameraRig == null)
                {
                    _cameraRig = _camera.gameObject.AddComponent<BoardCameraRig>();
                    _ownsRig = true;
                }
            }

            _cameraRig.Configure(_config);
        }

        private void BuildSpecs(
            MatchView view,
            BoardRenderState state,
            List<CardSpec> specs)
        {
            foreach (var player in view.Players)
            {
                var localSeat = _layout.ToLocalSeat(player.Index, _selfPlayer);
                AddFieldSpecs(player, localSeat, state, specs);
                AddGuardianSpecs(view, player, localSeat, specs);
                AddDamageSpecs(player, localSeat, state, specs);
            }

            AddHandSpecs(view, state, specs);
        }

        private void AddFieldSpecs(
            PlayerView player,
            int localSeat,
            BoardRenderState state,
            List<CardSpec> specs)
        {
            AddFieldCard(player, localSeat, PlaymatLayout.VanguardSlot, player.Vanguard, state, specs);

            if (player.RearGuards == null)
                return;

            for (var slot = 0; slot < player.RearGuards.Length; slot++)
                AddFieldCard(player, localSeat, slot, player.RearGuards[slot], state, specs);
        }

        private void AddFieldCard(
            PlayerView player,
            int localSeat,
            int slot,
            CardView card,
            BoardRenderState state,
            List<CardSpec> specs)
        {
            if (card == null)
                return;

            var key = new BoardSlotKey(player.Index, slot);
            specs.Add(new CardSpec
            {
                Key = "F:" + player.Index + ":" + slot,
                Ref = BoardCardRef.Field(player.Index, slot, card),
                Art = ResolveArt(card.PrintingId),
                Position = _layout.CirclePosition(localSeat, slot),
                BaseRotation = Quaternion.Euler(0f, _layout.BaseYaw(localSeat), 0f),
                FaceUp = card.FaceUp,
                Rested = card.Rested,
                Highlight = state.Highlights.Contains(key)
                    ? _config.highlightColor
                    : (Color?)null,
            });
        }

        private void AddGuardianSpecs(
            MatchView view,
            PlayerView player,
            int localSeat,
            List<CardSpec> specs)
        {
            var guardians = player.Guardian ?? new List<CardView>();
            var battleCards = view.Battle != null && view.Battle.AttackerPlayer != player.Index
                ? view.Battle.GuardCards ?? new List<CardView>()
                : new List<CardView>();
            var total = guardians.Count + battleCards.Count;
            if (total == 0)
                return;

            for (var i = 0; i < guardians.Count; i++)
            {
                var card = guardians[i];
                specs.Add(new CardSpec
                {
                    Key = "G:" + player.Index + ":" + card.InstanceId,
                    Ref = BoardCardRef.Guardian(player.Index, i, card),
                    Art = ResolveArt(card.PrintingId),
                    Position = _layout.GuardianPosition(localSeat, i, total),
                    BaseRotation = Quaternion.Euler(0f, _layout.BaseYaw(localSeat), 0f),
                    FaceUp = true,
                    Rested = false,
                });
            }

            for (var i = 0; i < battleCards.Count; i++)
            {
                var card = battleCards[i];
                specs.Add(new CardSpec
                {
                    Key = "BG:" + player.Index + ":" + card.InstanceId,
                    Ref = BoardCardRef.Guardian(player.Index, guardians.Count + i, card),
                    Art = ResolveArt(card.PrintingId),
                    Position = _layout.GuardianPosition(
                        localSeat,
                        guardians.Count + i,
                        total),
                    BaseRotation = Quaternion.Euler(0f, _layout.BaseYaw(localSeat), 0f),
                    FaceUp = true,
                    Rested = false,
                });
            }
        }

        private void AddDamageSpecs(
            PlayerView player,
            int localSeat,
            BoardRenderState state,
            List<CardSpec> specs)
        {
            var faceUp = player.FaceUpDamage ?? new List<CardView>();
            var total = Mathf.Min(
                PlaymatLayout.DamageSlots,
                faceUp.Count + Mathf.Max(0, player.FaceDownDamage));

            for (var i = 0; i < total; i++)
            {
                var isUp = i < faceUp.Count;
                var card = isUp ? faceUp[i] : null;
                var highlight = DamageHighlight(state, i);
                specs.Add(new CardSpec
                {
                    Key = "D:" + player.Index + ":" + i,
                    Ref = BoardCardRef.Damage(player.Index, i, card, isUp),
                    Art = isUp
                        ? ResolveArt(card.PrintingId)
                        : BoardArt.Fallback(_config.damageColor),
                    Position = _layout.DamagePosition(localSeat, i),
                    BaseRotation = Quaternion.Euler(0f, _layout.BaseYaw(localSeat), 0f),
                    FaceUp = isUp,
                    Rested = true,
                    DamageLayout = true,
                    Highlight = highlight,
                });
            }
        }

        private Color? DamageHighlight(BoardRenderState state, int index)
        {
            if (!state.DamageChoice && !state.AbilityDamageTargeting)
                return null;

            if (state.AbilityDamageTargeting
                && state.AbilityDamageIndex == index)
            {
                return _config.selectedColor;
            }

            return _config.highlightColor;
        }

        private void AddHandSpecs(
            MatchView view,
            BoardRenderState state,
            List<CardSpec> specs)
        {
            var self = view.Players.FirstOrDefault(player => player.Index == view.You);
            if (self?.Hand == null)
                return;

            var count = self.Hand.Count;
            for (var i = 0; i < count; i++)
            {
                var card = self.Hand[i];
                GetHandViewPose(i, count, out var position, out var rotation, out var scale);
                Color? highlight = null;
                if (state.SelectedHandInstanceIds.Contains(card.InstanceId))
                    highlight = _config.selectedColor;
                else if (state.MulliganSelecting)
                    highlight = _config.highlightColor;

                specs.Add(new CardSpec
                {
                    Key = "H:" + card.InstanceId,
                    Ref = BoardCardRef.Hand(self.Index, i, card),
                    Art = ResolveArt(card.PrintingId),
                    Position = position,
                    BaseRotation = rotation,
                    FaceUp = true,
                    Rested = false,
                    Scale = scale,
                    IsHand = true,
                    HandIndex = i,
                    HandCount = count,
                    Highlight = highlight,
                });
            }
        }

        /// <summary>
        /// Рука висит в поле зрения камеры снизу по центру и всегда смотрит
        /// на игрока. При отсутствии камеры используется старый настольный
        /// вариант — для EditMode-проверок.
        /// </summary>
        private void GetHandViewPose(
            int index,
            int count,
            out Vector3 position,
            out Quaternion rotation,
            out float scale)
        {
            if (_camera == null)
                _camera = Camera.main;

            if (_camera == null)
            {
                var fallback = _layout.GetHandPose(index, count);
                position = fallback.Position;
                rotation = Quaternion.Euler(_config.handTilt, fallback.Yaw, 0f);
                scale = 1f;
                return;
            }

            var safeCount = Mathf.Max(1, count);
            var step = _config.handSpacing;
            if (safeCount > 1)
                step = Mathf.Min(step, _config.handViewMaxWidth / (safeCount - 1));

            var offset = index - (safeCount - 1) * 0.5f;
            var halfHeight = Mathf.Tan(
                _camera.fieldOfView * 0.5f * Mathf.Deg2Rad) * _config.handViewDistance;
            var x = offset * step;
            var y = (_config.handViewportY - 0.5f) * 2f * halfHeight
                + (1f - Mathf.Abs(offset) / safeCount) * _config.handViewArc;
            var z = _config.handViewDistance
                + Mathf.Abs(offset) * _config.handViewArc;

            position = _camera.transform.TransformPoint(new Vector3(x, y, z));
            var roll = -offset * _config.handViewRoll;
            rotation = _camera.transform.rotation
                * Quaternion.Euler(0f, 0f, roll)
                * Quaternion.Euler(-90f, 0f, 0f);
            scale = _config.handViewScale;
        }

        private void UpdateHandView()
        {
            if (_handBindings.Count == 0)
                return;

            if (_camera == null)
            {
                _camera = Camera.main;
                if (_camera == null)
                    return;
            }

            foreach (var binding in _handBindings)
            {
                if (binding.Card == null || binding.Card.IsDragging)
                    continue;

                GetHandViewPose(
                    binding.Index,
                    binding.Count,
                    out var position,
                    out var rotation,
                    out var scale);
                binding.Card.SetPose(
                    position,
                    rotation,
                    true,
                    false,
                    false,
                    false,
                    scale);
            }
        }

        private void UpdatePiles(MatchView view)
        {
            var self = view.Players.FirstOrDefault(player => player.Index == view.You);
            var opponent = view.Players.FirstOrDefault(player => player.Index != view.You);

            UpdatePileSide(self, _deckSelf, _dropSelf, _soulSelf);
            UpdatePileSide(opponent, _deckOpponent, _dropOpponent, _soulOpponent);

            var damageSelf = self != null
                ? self.FaceDownDamage + (self.FaceUpDamage?.Count ?? 0)
                : 0;
            var damageOpponent = opponent != null
                ? opponent.FaceDownDamage + (opponent.FaceUpDamage?.Count ?? 0)
                : 0;
            _damageZones[0]?.SetLabel("DAMAGE  " + damageSelf);
            _damageZones[1]?.SetLabel("DAMAGE  " + damageOpponent);

            if (_guardianZone != null)
            {
                var shield = view.Battle != null ? view.Battle.GuardShield : 0;
                var checks = view.Battle != null ? view.Battle.ChecksRemaining : 0;
                _guardianZone.SetLabel(
                    "GUARDIAN   SHIELD " + shield + "   CHECK " + checks);
            }
        }

        private void UpdatePileSide(
            PlayerView player,
            Pile3D deck,
            Pile3D drop,
            Pile3D soul)
        {
            if (deck == null)
                return;

            if (player == null)
            {
                deck.SetCount(0, null, "DECK", Color.white);
                drop.SetCount(0, null, "DROP", Color.white);
                soul.SetCount(0, null, "SOUL", _config.soulColor);
                return;
            }

            deck.SetCount(
                player.DeckCount,
                null,
                "DECK",
                new Color(0.20f, 0.34f, 0.60f));

            var topDrop = player.Drop != null && player.Drop.Count > 0
                ? player.Drop[player.Drop.Count - 1]
                : null;
            drop.SetCount(
                player.Drop?.Count ?? 0,
                topDrop != null ? ResolveArt(topDrop.PrintingId).Front : null,
                "DROP",
                new Color(0.30f, 0.30f, 0.40f));

            var topSoul = player.Soul != null && player.Soul.Count > 0
                ? player.Soul[player.Soul.Count - 1]
                : null;
            soul.SetCount(
                player.Soul?.Count ?? 0,
                topSoul != null ? ResolveArt(topSoul.PrintingId).Front : null,
                "SOUL",
                _config.soulColor);
        }

        private void UpdateSlots(BoardRenderState state)
        {
            _activeHighlights.Clear();
            foreach (var key in state.Highlights)
                _activeHighlights.Add(key);

            _validDropSlots.Clear();
            foreach (var key in state.DropTargets)
                _validDropSlots.Add(key);
            _guardianDropAllowed = state.GuardianDropAllowed;

            ApplySlotHighlights();
        }

        private void ApplySlotHighlights()
        {
            foreach (var slot in _slots)
            {
                var highlighted = _activeHighlights.Contains(slot.Key)
                    || (_dragging && _validDropSlots.Contains(slot.Key));
                slot.SetHighlighted(highlighted);
            }

            if (_guardianZone != null)
            {
                _guardianZone.SetHighlighted(_dragging && _guardianDropAllowed);
            }
        }

        private void Update()
        {
            UpdateHandView();

            var delta = Time.unscaledDeltaTime;
            foreach (var card in _cards.Values)
            {
                if (card != null)
                    card.Tick(delta);
            }

            HandlePointer();
        }

        private void HandlePointer()
        {
            if (!_hasRendered && _view == null)
                return;

            if (!TryReadPointer(out var pointer, out var pressed, out var held, out var released))
                return;

            if (pressed)
                OnPointerPressed(pointer);
            else if (held && _mode == PointerMode.Card && !_dragging)
                OnPointerHeld(pointer);
            else if (released)
                OnPointerReleased(pointer);
        }

        private static bool TryReadPointer(
            out Vector2 pointer,
            out bool pressed,
            out bool held,
            out bool released)
        {
            pointer = default;
            pressed = false;
            held = false;
            released = false;

            var mouse = Mouse.current;
            if (mouse != null)
            {
                pointer = mouse.position.ReadValue();
                pressed = mouse.leftButton.wasPressedThisFrame;
                held = mouse.leftButton.isPressed;
                released = mouse.leftButton.wasReleasedThisFrame;
                return true;
            }

            var touch = Touchscreen.current;
            if (touch == null)
                return false;

            var primary = touch.primaryTouch;
            pointer = primary.position.ReadValue();
            pressed = primary.press.wasPressedThisFrame;
            held = primary.press.isPressed;
            released = primary.press.wasReleasedThisFrame;
            return true;
        }

        private void OnPointerPressed(Vector2 pointer)
        {
            CancelPointer();
            if (IsPointerOverUi())
                return;

            var ray = GetRay(pointer);
            if (!TryRaycast(ray, out var card, out var slot, out var pile))
                return;

            _pressPosition = pointer;
            if (card != null)
            {
                _mode = PointerMode.Card;
                _pressedCard = card;
                _pressedCardRef = card.Ref;
                return;
            }

            if (slot != null)
            {
                _mode = PointerMode.Slot;
                _pressedSlot = slot;
                return;
            }

            if (pile != null)
            {
                _mode = PointerMode.Pile;
                _pressedPile = pile;
            }
        }

        private void OnPointerHeld(Vector2 pointer)
        {
            if (_pressedCard == null || _pressedCardRef.IsEmpty)
                return;

            if (!_pressedCardRef.IsField && !_pressedCardRef.IsHand)
                return;

            if (Vector2.Distance(pointer, _pressPosition)
                < Mathf.Max(2f, _config.dragThresholdPixels))
                return;

            _dragging = true;
            _pressedCard.BeginDrag();
            ApplySlotHighlights();
            UpdateDrag(pointer);
        }

        private void OnPointerReleased(Vector2 pointer)
        {
            if (_dragging)
            {
                UpdateDrag(pointer);
                FinishDrag(pointer);
                return;
            }

            if (_mode == PointerMode.Card && _pressedCard != null)
            {
                CardClicked?.Invoke(_pressedCardRef);
            }
            else if (_mode == PointerMode.Slot && _pressedSlot != null)
            {
                SlotClicked?.Invoke(_pressedSlot.Ref);
            }
            else if (_mode == PointerMode.Pile && _pressedPile != null)
            {
                PileClicked?.Invoke(_pressedPile.Ref);
            }

            CancelPointer();
        }

        private void UpdateDrag(Vector2 pointer)
        {
            if (!_dragging || _pressedCard == null)
                return;

            var ray = GetRay(pointer);
            var plane = new Plane(Vector3.up, new Vector3(0f, _config.cardLift, 0f));
            if (!plane.Raycast(ray, out var enter))
                return;

            var point = ray.GetPoint(enter);
            point.x = Mathf.Clamp(point.x, -_config.boardHalfWidth, _config.boardHalfWidth);
            point.z = Mathf.Clamp(point.z, -_config.boardHalfLength, _config.boardHalfLength);
            _pressedCard.DragTo(point);

            if (_layout.TryFindDropTarget(point, _selfPlayer, out var target))
            {
                _dragTarget = target;
                ShowDropIndicator(target);
                var key = new BoardSlotKey(target.Player, target.Slot);
                var valid = target.Zone == BoardZone.Guardian
                    ? _guardianDropAllowed
                    : _validDropSlots.Contains(key);
                _dropIndicator.SetColor(valid ? _config.selectedColor : _config.damageColor);
            }
            else
            {
                _dragTarget = null;
                _dropIndicator.gameObject.SetActive(false);
            }
        }

        private void FinishDrag(Vector2 pointer)
        {
            var card = _pressedCard;
            var source = _pressedCardRef;
            var target = _dragTarget;
            _dragging = false;
            _dragTarget = null;
            _dropIndicator.gameObject.SetActive(false);

            if (card == null)
            {
                CancelPointer();
                return;
            }

            if (IsPointerOverUi() || !target.HasValue)
            {
                card.ReturnToOrigin();
                CancelPointer();
                return;
            }

            var targetValue = target.Value;
            var targetRef = targetValue.ToRef();

            if (source.IsHand)
                _handBindings.RemoveAll(binding => binding.Card == card);

            // Атака — это клик по цели, карта остаётся на своём круге.
            if ((source.IsField && targetValue.Player != source.Player)
                || (source.IsHand && targetValue.Player != source.Player
                    && targetValue.Zone != BoardZone.Guardian))
            {
                card.ReturnToOrigin();
            }
            else
            {
                var localSeat = _layout.ToLocalSeat(targetValue.Player, _selfPlayer);
                var position = targetValue.Zone == BoardZone.Guardian
                    ? _layout.GuardianPosition(localSeat, 0, 1)
                    : _layout.CirclePosition(localSeat, targetValue.Slot);
                var restYaw = !source.IsHand && card.IsRested ? 90f : 0f;
                var rotation = Quaternion.Euler(
                    0f,
                    _layout.BaseYaw(localSeat) + restYaw,
                    0f);
                card.DropAt(position, rotation);
            }

            CardDropped?.Invoke(source, targetRef);
            CancelPointer();
        }

        private void ShowDropIndicator(BoardDropTarget target)
        {
            var localSeat = _layout.ToLocalSeat(target.Player, _selfPlayer);
            var position = target.Zone == BoardZone.Guardian
                ? _layout.GuardianPosition(localSeat, 0, 1)
                : _layout.CirclePosition(localSeat, target.Slot);
            _dropIndicator.transform.localPosition = new Vector3(
                position.x,
                0.014f,
                position.z);
            _dropIndicator.gameObject.SetActive(true);
        }

        private bool TryRaycast(
            Ray ray,
            out Card3D card,
            out BoardSlotView slot,
            out Pile3D pile)
        {
            card = null;
            slot = null;
            pile = null;

            var hits = Physics.RaycastAll(ray, 100f, ~0, QueryTriggerInteraction.Ignore);
            if (hits.Length == 0)
                return false;

            Array.Sort(hits, (a, b) => a.distance.CompareTo(b.distance));
            foreach (var hit in hits)
            {
                if (hit.collider == null)
                    continue;

                card = hit.collider.GetComponentInParent<Card3D>();
                if (card != null && card.gameObject.activeInHierarchy)
                    return true;

                slot = hit.collider.GetComponentInParent<BoardSlotView>();
                if (slot != null)
                    return true;

                pile = hit.collider.GetComponentInParent<Pile3D>();
                if (pile != null)
                    return true;
            }

            return false;
        }

        private Ray GetRay(Vector2 screenPoint)
        {
            if (_camera == null)
                _camera = Camera.main;
            return _camera != null
                ? _camera.ScreenPointToRay(screenPoint)
                : new Ray(Vector3.up * 10f, Vector3.down);
        }

        private static bool IsPointerOverUi()
        {
            var eventSystem = EventSystem.current;
            return eventSystem != null && eventSystem.IsPointerOverGameObject();
        }

        private Card3D RentCard()
        {
            while (_pool.Count > 0)
            {
                var pooled = _pool.Pop();
                if (pooled == null)
                    continue;
                pooled.gameObject.SetActive(true);
                return pooled;
            }

            if (_config.cardPrefab != null)
            {
                var instance = Instantiate(_config.cardPrefab, _cardsRoot);
                return instance;
            }

            if (_cardsRoot == null)
            {
                _cardsRoot = new GameObject("Cards").transform;
                _cardsRoot.SetParent(transform, false);
            }

            return Card3D.Create(_cardsRoot, _config);
        }

        private void ReleaseCard(Card3D card)
        {
            if (card == null)
                return;
            card.SetHighlight(null);
            card.gameObject.SetActive(false);
            _pool.Push(card);
        }

        private void ClearCards()
        {
            foreach (var card in _cards.Values)
                ReleaseCard(card);
            _cards.Clear();
        }

        private void CancelPointer()
        {
            if (_pressedCard != null && _dragging)
                _pressedCard.ReturnToOrigin();
            _mode = PointerMode.None;
            _pressedCard = null;
            _pressedSlot = null;
            _pressedPile = null;
            _dragging = false;
            _dragTarget = null;
            if (_dropIndicator != null)
                _dropIndicator.gameObject.SetActive(false);
            ApplySlotHighlights();
        }

        private BoardArt ResolveArt(string printingId)
        {
            if (ArtProvider != null)
            {
                var art = ArtProvider(printingId);
                if (art != null)
                    return art;
            }

            return BoardArt.Fallback(BoardTextures.AccentFor(printingId));
        }

        private int LocalToPlayer(int localSeat) =>
            _layout.ToPlayer(localSeat, _selfPlayer);

        private GameObject CreateBox(
            string name,
            Vector3 position,
            Vector3 scale,
            Color color)
        {
            return CreateBox(name, position, scale, BoardMaterials.CreateLit(color));
        }

        private GameObject CreateBox(
            string name,
            Vector3 position,
            Vector3 scale,
            Material material)
        {
            var box = GameObject.CreatePrimitive(PrimitiveType.Cube);
            box.name = name;
            box.transform.SetParent(transform, false);
            box.transform.localPosition = position;
            box.transform.localScale = scale;

            var collider = box.GetComponent<Collider>();
            if (collider != null)
            {
                if (Application.isPlaying)
                    Destroy(collider);
                else
                    DestroyImmediate(collider);
            }

            var renderer = box.GetComponent<MeshRenderer>();
            renderer.sharedMaterial = material;
            BoardMaterials.SetShadows(renderer, false);
            return box;
        }

        private void OnDestroy()
        {
            if (_instance == this)
                _instance = null;

            if (_cameraRig != null && _ownsRig)
            {
                if (Application.isPlaying)
                    Destroy(_cameraRig);
                else
                    DestroyImmediate(_cameraRig);
            }
        }

        private sealed class HandCardBinding
        {
            public HandCardBinding(Card3D card, int index, int count)
            {
                Card = card;
                Index = index;
                Count = count;
            }

            public Card3D Card { get; }
            public int Index { get; }
            public int Count { get; }
        }

        private sealed class CardSpec
        {
            public string Key;
            public BoardCardRef Ref;
            public BoardArt Art;
            public Vector3 Position;
            public Quaternion BaseRotation;
            public bool FaceUp;
            public bool Rested;
            public bool DamageLayout;
            public float Scale = 1f;
            public bool IsHand;
            public int HandIndex;
            public int HandCount;
            public Color? Highlight;
        }
    }
}