package amqp

import (
	"crypto/rand"
	"fmt"
	"io"
)

func NewUUIDv4() (string, error) {
	var uuid [16]byte

	_, err := io.ReadFull(rand.Reader, uuid[:])

	if err != nil {
		return "", err
	}

	uuid[6] = (uuid[6] & 0x0f) | 0x40 // Version 4
	uuid[8] = (uuid[8] & 0x3f) | 0x80 // Variant is 10

	return fmt.Sprintf("%x-%x-%x-%x-%x", uuid[0:4], uuid[4:6], uuid[6:8], uuid[8:10], uuid[10:]), nil
}