package grains

import "errors"

// Square just takes 1 * 2^sq
func Square(sq int) (uint64, error) {
	if sq > 0 && sq < 65 {
		return (1 << uint(sq-1)), nil
	}
	return 0, errors.New("Invalid Square Requested")
}

// TotalForSquare calculates the total number
// for all squares up to sq (cause why not)
func TotalForSquare(sq int) (uint64, error) {
	if sq < 0 || sq > 64 {
		return 0, errors.New("Invalid Square Requested")
	}
	var ret uint64
	for i := 0; i <= sq; i++ {
		ret = (ret << 1) | 1
	}
	return ret, nil
}

// Total calculates the total for the entire board
func Total() uint64 {
	ret, _ := TotalForSquare(64)
	return ret
}