using System;
using System.Collections.Generic;
using System.Linq;
using Godot;

/// <summary>
///     办公格子/图块对象
/// </summary>
public partial class Cube : StaticBody2D, ITileDraggable {
    // 定义各种家具的占用区域
    private static readonly Rect2I tableRect = new(0, 0, 3, 2);
    private static readonly Rect2I table2Rect = new(0, -1, 3, 1);
    private static readonly Rect2I chairRect = new(1, 1, 1, 2);
    private static readonly Rect2I chair2Rect = new(1, -2, 1, 2);
    private static readonly Rect2I equipRect = new(0, 0, 3, 2);
    private static readonly Rect2I equip2Rect = new(0, -1, 3, 1);

    // 定义桌子的主题映射
    private static readonly TileMapping[] tableThemes = {
        new(new Vector2I(1, 30), tableRect),
        new(new Vector2I(4, 30), tableRect),
        new(new Vector2I(7, 30), tableRect),
        new(new Vector2I(7, 28), tableRect),
        new(new Vector2I(10, 28), tableRect)
    };

    // 定义第二种桌子的主题映射
    private static readonly TileMapping[] table2Themes = {
        new(new Vector2I(1, 31), table2Rect),
        new(new Vector2I(4, 31), table2Rect),
        new(new Vector2I(7, 31), table2Rect),
        new(new Vector2I(7, 29), table2Rect),
        new(new Vector2I(10, 29), table2Rect)
    };

    // 定义椅子的主题映射
    private static readonly TileMapping[] chairThemes = {
        new(new Vector2I(-1, 7), chairRect),
        new(new Vector2I(0, 7), chairRect),
        new(new Vector2I(-1, 9), chairRect),
        new(new Vector2I(0, 9), chairRect)
    };

    // 定义第二种椅子的主题映射
    private static readonly TileMapping[] chair2Themes = {
        new(new Vector2I(-1, 10), chair2Rect),
        new(new Vector2I(0, 10), chair2Rect),
        new(new Vector2I(-1, 12), chair2Rect),
        new(new Vector2I(0, 12), chair2Rect)
    };

    // 定义设备的主题映射
    private static readonly TileMapping[] equipThemes = {
        // 一台笔记本电脑
        new(new Vector2I(13, 26), equipRect),
        // 一台笔记本电脑加一台显示器
        new(new Vector2I(7, 26), equipRect),
        // 一台台式机
        new(new Dictionary<Vector2I, Vector2I> {
            [new Vector2I(0, 0)] = new(11, 17),
            [new Vector2I(1, 0)] = new(8, 32),
            [new Vector2I(2, 0)] = new(9, 32),
            [new Vector2I(0, 1)] = new(11, 18),
            [new Vector2I(1, 1)] = new(8, 33),
            [new Vector2I(2, 1)] = new(9, 33)
        }),
        // 一台台式机加一台显示器
        new(new Vector2I(7, 32), equipRect)
    };

    // 定义第二种设备的主题映射
    private static readonly TileMapping[] equip2Themes = {
        // 一台笔记本电脑
        new(new Vector2I(13, 31), equip2Rect),
        // 一台笔记本电脑加一台显示器
        new(new Dictionary<Vector2I, Vector2I> {
            [new Vector2I(0, -1)] = new(13, 32),
            [new Vector2I(1, -1)] = new(10, 7),
            [new Vector2I(2, -1)] = new(15, 32)
        }),
        // 一台台式机
        new(new Dictionary<Vector2I, Vector2I> {
            [new Vector2I(0, -1)] = new(13, 32),
            [new Vector2I(1, -1)] = new(14, 32),
            [new Vector2I(2, -1)] = new(15, 30)
        }),
        // 一台台式机加一台显示器
        new(new Vector2I(13, 33), equip2Rect)
    };

    private static readonly Rect2I tileRect = new(-1, -2, 4, 5);

    private static readonly ITileDraggable.SpecialTile[] specialTiles = {
        new(new Vector2I(1, -1), Lab.MapNodeType.SeatDown | Lab.MapNodeType.Walkable),
        new(new Vector2I(1, 2), Lab.MapNodeType.SeatUp | Lab.MapNodeType.Walkable)
    };

    private static readonly HashSet<Vector2I> blockerTiles = new(new Vector2I[] {
        new(0, 0),
        new(1, 0),
        new(2, 0),
        new(0, 1),
        new(1, 1),
        new(2, 1)
    });

    private int _chair2ThemeIdx;
    private int _chairThemeIdx;

    private bool _draggable;
    private int _equip2ThemeIdx;
    private int _equipThemeIdx;

    private bool _isCollided = true;

    private Vector2I _mouseOffset;
    private int _table2ThemeIdx;

    private int _tableThemeIdx;

    /// <summary>
    ///     是否可拖拽
    /// </summary>
    public bool Draggable {
        get => _draggable;
        set {
            if (value == _draggable) return;
            _draggable = value;
        }
    }

    /// <summary>
    ///     唯一标识符
    /// </summary>
    public Guid Id { get; } = Guid.NewGuid();

    /// <summary>
    ///     在网格中的位置
    /// </summary>
    public Vector2I TilePosition { get; set; } = new(5, 5);

    /// <summary>
    ///     是否处于碰撞状态（显示红色背景）
    /// </summary>
    public bool IsCollided {
        get => _isCollided;
        set {
            if (_isCollided == value) return;
            _isCollided = value;
            if (value)
                GetNode<Polygon2D>("RedBG").Show();
            else
                GetNode<Polygon2D>("RedBG").Hide();
        }
    }

    /// <summary>
    ///     占用矩形区域
    /// </summary>
    public Rect2I TileRect => tileRect;

    /// <summary>
    ///     鼠标拖拽偏移
    /// </summary>
    public Vector2I MouseOffset => _mouseOffset;


    /// <summary>
    ///     特殊图块（如座位）
    /// </summary>
    public ITileDraggable.SpecialTile[] SpecialTiles => specialTiles;

    /// <summary>
    ///     获取指定位置的图块类型
    /// </summary>
    /// <param name="pos">相对位置</param>
    /// <returns>图块类型</returns>
    public Lab.MapNodeType GetTileType(Vector2I pos) {
        GD.Print($"query position of {pos}");
        if (blockerTiles.Contains(pos)) return Lab.MapNodeType.Blocker;
        if (specialTiles.Any(t => t.Position == pos)) return specialTiles.First(t => t.Position == pos).NodeType;
        return Lab.MapNodeType.Walkable;
    }

    // Called when the node enters the scene tree for the first time.
    /// <summary>
    ///     节点进入场景树时调用
    /// </summary>
    public override void _Ready() {
        RandomChangeTheme();
        IsCollided = false;
    }

    /// <summary>
    ///     处理输入事件
    /// </summary>
    /// <param name="viewport">视口</param>
    /// <param name="event">输入事件</param>
    /// <param name="shapeIdx">形状索引</param>
    public override void _InputEvent(Viewport viewport, InputEvent @event, int shapeIdx) {
        if (@event.IsActionPressed("mouse_left_press")) {
            if (Draggable) {
                var parent = GetParent<Lab>();
                parent.Pickup(this);
                var desk = GetNode<TileMapLayer>("Desk");
                _mouseOffset = desk.LocalToMap(GetLocalMousePosition());
                GD.Print($"_mouseOffset = {_mouseOffset}");
            }
        }
        else if (@event.IsActionReleased("mouse_left_press")) {
            if (_isCollided) return;
            var parent = GetParent<Lab>();
            parent.PutDown(this);
        }

        base._InputEvent(viewport, @event, shapeIdx);
    }

    // Called every frame. 'delta' is the elapsed time since the previous frame.
    /// <summary>
    ///     每帧处理
    /// </summary>
    /// <param name="delta">时间间隔</param>
    public override void _Process(double delta) {
        GlobalPosition = TilePosition * 48;
    }

    /// <summary>
    ///     随机更换主题样式
    /// </summary>
    public void RandomChangeTheme() {
        _tableThemeIdx = GD.RandRange(0, tableThemes.Length - 1);
        _chairThemeIdx = GD.RandRange(0, chairThemes.Length - 1);
        _equipThemeIdx = GD.RandRange(0, equipThemes.Length - 1);

        _table2ThemeIdx = GD.RandRange(0, table2Themes.Length - 1);
        _chair2ThemeIdx = GD.RandRange(0, chair2Themes.Length - 1);
        _equip2ThemeIdx = GD.RandRange(0, equip2Themes.Length - 1);

        tableThemes[_tableThemeIdx].Apply(GetNode<TileMapLayer>("Desk"));
        chairThemes[_chairThemeIdx].Apply(GetNode<TileMapLayer>("Chair"));
        equipThemes[_equipThemeIdx].Apply(GetNode<TileMapLayer>("Equip"));
        table2Themes[_table2ThemeIdx].Apply(GetNode<TileMapLayer>("Desk2"));
        chair2Themes[_chair2ThemeIdx].Apply(GetNode<TileMapLayer>("Chair2"));
        equip2Themes[_equip2ThemeIdx].Apply(GetNode<TileMapLayer>("Equip2"));
    }

    /// <summary>
    ///     设置椅子朝向（待实现）
    /// </summary>
    /// <param name="target">目标位置</param>
    /// <param name="idx">索引</param>
    public void ChairFaceTo(Vector2I target, int idx) {
        if (idx == 0) {
            var theme = chairThemes[_chairThemeIdx];
        }
    }
}