package mutable

import "github.com/samber/lo/internal/rand"

// Shuffle returns an array of shuffled values. Uses the Fisher-Yates shuffle algorithm.
// Play: https://go.dev/play/p/2xb3WdLjeSJ
func Shuffle[T any, Slice ~[]T](collection Slice) {
	rand.Shuffle(len(collection), func(i, j int) {
		collection[i], collection[j] = collection[j], collection[i]
	})
}

// Reverse reverses array so that the first element becomes the last, the second element becomes the second to last, and so on.
// Play: https://go.dev/play/p/O-M5pmCRgzV
func Reverse[T any, Slice ~[]T](collection Slice) {
	length := len(collection)
	half := length / 2

	for i := 0; i < half; i = i + 1 {
		j := length - 1 - i
		collection[i], collection[j] = collection[j], collection[i]
	}
}