using System.Collections.Generic;
using Vector2I = Vector.Vector2I;

using static IPiece;
public abstract class AbstractPiece(string name = "", Vector2I? pos = null,
        IPieceOn? on = null) : IPiece {
    private Vector2I pos = pos ?? new(); // 注意这个坐标的非像素坐标而是棋盘坐标
    private bool isSelected = false;
    protected string name = name;
    private Dictionary<string, object> data = [];
    protected IPieceOn? on = on;

    public virtual IPieceOn? On { get => on; set => on = value; }

    public virtual Vector2I Pos {
        get => pos;
        set {
            if (pos != value) {
                var oldPos = pos;
                pos = value;
                on?.OnPos(this, oldPos);
            }
        }
    }

    public virtual bool IsSelected {
        get => isSelected;
        set {
            if (isSelected != value) {
                var oldIsSelected = isSelected;
                isSelected = value;
                on?.OnSelected(this, oldIsSelected);
            }
        }
    }

    public virtual string Name {
        get => name;
        set {
            if (name != value) {
                var oldName = name;
                name = value;
                on?.OnName(this, oldName);
            }
        }
    }

    public virtual Dictionary<string, object> Data {
        get => data;
        set => data = value;
    }

    public virtual bool Move(Vector2I pos) {
        if (!CanMove(pos)) {
            return false;
        }
        Pos = pos;
        on?.OnMove(this, pos);
        return true;
    }

    public abstract bool CanMove(Vector2I to);

    public override string ToString() {
        return $"{Name} at {pos}";
    }
}