<?php

/**
 *
 * Function code for the complex subtraction operation
 *
 * @copyright  Copyright (c) 2013-2018 Mark Baker (https://github.com/MarkBaker/PHPComplex)
 * @license    https://opensource.org/licenses/MIT    MIT
 */
namespace Complex;

/**
 * Subtracts two or more complex numbers
 *
 * @param     array of string|integer|float|Complex    $complexValues   The numbers to subtract
 * @return    Complex
 */
if (!function_exists(__NAMESPACE__ . '\\subtract')) {
    function subtract(...$complexValues): Complex
    {
        if (count($complexValues) < 2) {
            throw new \Exception('This function requires at least 2 arguments');
        }

        $base = array_shift($complexValues);
        $result = clone Complex::validateComplexArgument($base);

        foreach ($complexValues as $complex) {
            $complex = Complex::validateComplexArgument($complex);

            if ($result->isComplex() && $complex->isComplex() &&
                $result->getSuffix() !== $complex->getSuffix()) {
                throw new Exception('Suffix Mismatch');
            }

            $real = $result->getReal() - $complex->getReal();
            $imaginary = $result->getImaginary() - $complex->getImaginary();

            $result = new Complex(
                $real,
                $imaginary,
                ($imaginary == 0.0) ? null : max($result->getSuffix(), $complex->getSuffix())
            );
        }

        return $result;
    }
}
