<?php

namespace TablePress\PhpOffice\PhpSpreadsheet\Calculation\Statistical;

use TablePress\PhpOffice\PhpSpreadsheet\Calculation\ArrayEnabled;
use TablePress\PhpOffice\PhpSpreadsheet\Calculation\Exception;
use TablePress\PhpOffice\PhpSpreadsheet\Calculation\Information\ExcelError;
use TablePress\PhpOffice\PhpSpreadsheet\Calculation\MathTrig;
use TablePress\PhpOffice\PhpSpreadsheet\Shared\IntOrFloat;

class Permutations
{
	use ArrayEnabled;

	/**
	 * PERMUT.
	 *
	 * Returns the number of permutations for a given number of objects that can be
	 *        selected from number objects. A permutation is any set or subset of objects or
	 *        events where internal order is significant. Permutations are different from
	 *        combinations, for which the internal order is not significant. Use this function
	 *        for lottery-style probability calculations.
	 *
	 * @param mixed $numObjs Integer number of different objects
	 *                      Or can be an array of values
	 * @param mixed $numInSet Integer number of objects in each permutation
	 *                      Or can be an array of values
	 *
	 * @return array<mixed>|float|int|string Number of permutations, or a string containing an error
	 *         If an array of numbers is passed as an argument, then the returned result will also be an array
	 *            with the same dimensions
	 */
	public static function PERMUT($numObjs, $numInSet)
	{
		if (is_array($numObjs) || is_array($numInSet)) {
			return self::evaluateArrayArguments([self::class, __FUNCTION__], $numObjs, $numInSet);
		}

		try {
			$numObjs = StatisticalValidations::validateInt($numObjs);
			$numInSet = StatisticalValidations::validateInt($numInSet);
		} catch (Exception $e) {
			return $e->getMessage();
		}

		if ($numObjs < $numInSet) {
			return ExcelError::NAN();
		}
		/** @var float|int|string */
		$result1 = MathTrig\Factorial::fact($numObjs);
		if (is_string($result1)) {
			return $result1;
		}
		/** @var float|int|string */
		$result2 = MathTrig\Factorial::fact($numObjs - $numInSet);
		if (is_string($result2)) {
			return $result2;
		}
		$result = round($result1 / $result2);

		return IntOrFloat::evaluate($result);
	}

	/**
	 * PERMUTATIONA.
	 *
	 * Returns the number of permutations for a given number of objects (with repetitions)
	 *     that can be selected from the total objects.
	 *
	 * @param mixed $numObjs Integer number of different objects
	 *                      Or can be an array of values
	 * @param mixed $numInSet Integer number of objects in each permutation
	 *                      Or can be an array of values
	 *
	 * @return array<mixed>|float|int|string Number of permutations, or a string containing an error
	 *         If an array of numbers is passed as an argument, then the returned result will also be an array
	 *            with the same dimensions
	 */
	public static function PERMUTATIONA($numObjs, $numInSet)
	{
		if (is_array($numObjs) || is_array($numInSet)) {
			return self::evaluateArrayArguments([self::class, __FUNCTION__], $numObjs, $numInSet);
		}

		try {
			$numObjs = StatisticalValidations::validateInt($numObjs);
			$numInSet = StatisticalValidations::validateInt($numInSet);
		} catch (Exception $e) {
			return $e->getMessage();
		}

		if ($numObjs < 0 || $numInSet < 0) {
			return ExcelError::NAN();
		}

		$result = $numObjs ** $numInSet;

		return IntOrFloat::evaluate($result);
	}
}
