<?php

namespace Money;

/**
 * Money calculations abstracted away from the Money value object.
 *
 * @author Frederik Bosch <f.bosch@genkgo.nl>
 */
interface Calculator
{
    /**
     * Returns whether the calculator is supported in
     * the current server environment.
     *
     * @return bool
     */
    public static function supported();

    /**
     * Compare a to b.
     *
     * @param string $a
     * @param string $b
     *
     * @return int
     */
    public function compare($a, $b);

    /**
     * Add added to amount.
     *
     * @param string $amount
     * @param string $addend
     *
     * @return string
     */
    public function add($amount, $addend);

    /**
     * Subtract subtrahend from amount.
     *
     * @param string $amount
     * @param string $subtrahend
     *
     * @return string
     */
    public function subtract($amount, $subtrahend);

    /**
     * Multiply amount with multiplier.
     *
     * @param string           $amount
     * @param int|float|string $multiplier
     *
     * @return string
     */
    public function multiply($amount, $multiplier);

    /**
     * Divide amount with divisor.
     *
     * @param string           $amount
     * @param int|float|string $divisor
     *
     * @return string
     */
    public function divide($amount, $divisor);

    /**
     * Round number to following integer.
     *
     * @param string $number
     *
     * @return string
     */
    public function ceil($number);

    /**
     * Round number to preceding integer.
     *
     * @param string $number
     *
     * @return string
     */
    public function floor($number);

    /**
     * Returns the absolute value of the number.
     *
     * @param string $number
     *
     * @return string
     */
    public function absolute($number);

    /**
     * Round number, use rounding mode for tie-breaker.
     *
     * @param int|float|string $number
     * @param int              $roundingMode
     *
     * @return string
     */
    public function round($number, $roundingMode);

    /**
     * Share amount among ratio / total portions.
     *
     * @param string           $amount
     * @param int|float|string $ratio
     * @param int|float|string $total
     *
     * @return string
     */
    public function share($amount, $ratio, $total);

    /**
     * Get the modulus of an amount.
     *
     * @param string           $amount
     * @param int|float|string $divisor
     *
     * @return string
     */
    public function mod($amount, $divisor);
}