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

public abstract class AbstractPiece : IPiece {
    private Vector2I pos; // 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;
    private Dictionary<string, object> data = new();

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

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

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

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

    public event EventHandler<Vector2I> OnPos;
    public event EventHandler<Vector2I> OnMove;
    public event EventHandler<bool> OnSelected;
    public event EventHandler<string> OnName;

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

    public abstract bool CanMove(Vector2I to);

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

    public AbstractPiece(string name = "", Vector2I pos = null) {
        this.name = name;
        this.pos = pos ?? new();
    }
}