package me.dvorkin;

import java.util.Random;

public class NimModel {
	private int[] piles;
	private boolean move;
	
	public NimModel() {
		move = true;
		Random random = new Random();
		piles = new int[5];
		for (int i = 0; i < piles.length; i++) {
			piles[i] = random.nextInt(10) + 1;
		}
	}
	
	public int[] getField() {
		return piles.clone();
	}
	
	/**
	 * @return true if first player is to move
	 */
	public boolean whoMoves() {
		return move;
	}
	
	public boolean isOver() {
		for (int i : piles) {
			if (i != 0) {
				return false;
			}
		}
		return true;
	}
	
	public boolean update(int index, int amount) {
		if (index < 0 || index >= piles.length) {
			return false;
		}
		if (amount <= 0 || amount > piles[index]) {
			return false;
		}
		piles[index] -= amount;
		move ^= true;
		return true;
	}
}