xchess/lib/piece-stat.js

Chess Engine

import {Color} from './color.js'
import {King, Queen, Rook, Bishop, Knight, Pawn} from './standart-piece.js'

export function Weight(pieceList){
	let weight = 0;
	for(const piece of pieceList)
		weight += piece.weight;
	return weight;
}

export function Advantage(pieceList, color = Color.white){
	let advantage = 0;
	for(const piece of pieceList)
		advantage += piece.advantage(color);
	return advantage;
}

function CreateStat(){
	return {
		count: 0,
		weight: 0,
		advantage: 0,
		pieces: {},
	};
}

function AddToStat(stat, piece){
	stat.count ++;
	stat.weight += piece.weight;
	stat.advantage += piece.advantage();
	const name = piece.name.toLowerCase();
	const count = stat.pieces[name] ?? 0;
	stat.pieces[name] = count + 1;
}

export function PiecesStat(pieceList){
	const white = CreateStat();
	const black = CreateStat();
	const advantage = 0;
	const stat = {... CreateStat(), white, black};
	for(const piece of pieceList){
		AddToStat(stat, piece);
		if(Color.isWhite(piece.color)){
			AddToStat(white, piece);
		} else {
			AddToStat(black, piece);
		}
	}
	return stat;
}