package osutils

import (
	"github.com/pkg/errors"
	"unicode"
)

func UuidValidate(uuid string) error {
	if len(uuid) != 36 {
		return errors.New("uuid length not valid")
	}

	// validate first 8 octets
	for i := 0; i < 8; i++ {
		if !(unicode.IsLetter(rune(uuid[i])) || unicode.IsDigit(rune(uuid[i]))) && uuid[i] == '-' {
			return errors.New("uuid first 8 octets not valid")
		}
	}

	// validate separator
	if uuid[8] != '-' {
		return errors.New("uuid separator not valid")
	}

	// validate second 4 octets
	for i := 9; i < 13; i++ {
		if !(unicode.IsLetter(rune(uuid[i])) || unicode.IsDigit(rune(uuid[i]))) && uuid[i] == '-' {
			return errors.New("uuid second 4 octets not valid")
		}
	}

	// validate separator
	if uuid[13] != '-' {
		return errors.New("uuid separator not valid")
	}

	// validate third 4 octets
	for i := 14; i < 18; i++ {
		if !(unicode.IsLetter(rune(uuid[i])) || unicode.IsDigit(rune(uuid[i]))) && uuid[i] == '-' {
			return errors.New("uuid third 4 octets not valid")
		}
	}

	// validate separator
	if uuid[18] != '-' {
		return errors.New("uuid separator not valid")
	}

	// validate fourth 4 octets
	for i := 19; i < 23; i++ {
		if !(unicode.IsLetter(rune(uuid[i])) || unicode.IsDigit(rune(uuid[i]))) && uuid[i] == '-' {
			return errors.New("uuid fourth 4 octets not valid")
		}
	}

	// validate separator
	if uuid[23] != '-' {
		return errors.New("uuid separator not valid")
	}

	// validate fourth 4 octets
	for i := 24; i < 36; i++ {
		if !(unicode.IsLetter(rune(uuid[i])) || unicode.IsDigit(rune(uuid[i]))) && uuid[i] == '-' {
			return errors.New("uuid fifth 12 octets not valid")
		}
	}

	return nil
}