muonsoft / validation

//

// Permission is hereby granted, free of charge, to any person obtaining

// a copy of this software and associated documentation files (the

// "Software"), to deal in the Software without restriction, including

// without limitation the rights to use, copy, modify, merge, publish,

// distribute, sublicense, and/or sell copies of the Software, and to

// permit persons to whom the Software is furnished to do so, subject to

// the following conditions:

//

// The above copyright notice and this permission notice shall be

// included in all copies or substantial portions of the Software.

//

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE

// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION

// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION

// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

// Package uuid is a port of https://github.com/gofrs/uuid with functions

// only for parsing UUID from string.

package uuid

import (

	"bytes"

	"encoding/hex"

	"errors"

	"fmt"

)

var (

	ErrTooShort               = errors.New("too short")

	ErrTooLong                = errors.New("too long")

	ErrInvalidHyphenPlacement = errors.New("invalid hyphen placement")

	ErrInvalid                = errors.New("invalid")

)

// Size of a UUID in bytes.

const Size = 16

// UUID is an array type to represent the value of a UUID, as defined in RFC-4122.

type UUID [Size]byte

// UUID versions.

const (

	_  byte = iota

	V1      // Version 1 (date-time and MAC address)

	_       // Version 2 (date-time and MAC address, DCE security version) [removed]

	V3      // Version 3 (namespace name-based)

	V4      // Version 4 (random)

	V5      // Version 5 (namespace name-based)

	V6      // Version 6 (k-sortable timestamp and random data, field-compatible with v1) [peabody draft]

	V7      // Version 7 (k-sortable timestamp and random data) [peabody draft]

	_       // Version 8 (k-sortable timestamp, meant for custom implementations) [peabody draft] [not implemented]

)

// UUID layout variants.

const (

	VariantNCS byte = iota

	VariantRFC4122

	VariantMicrosoft

	VariantFuture

)

// FromString returns a UUID parsed from the input string.

// Input is expected in a form accepted by UnmarshalText.

func FromString(input string) (UUID, error) {

	u := UUID{}

	err := u.UnmarshalText([]byte(input))

	return u, err

}

func CanonicalFromString(input string) (UUID, error) {

	u := UUID{}

	if len(input) < 36 {

		return u, ErrTooShort

	}

	if len(input) > 36 {

		return u, ErrTooLong

	}

	err := u.decodeCanonical([]byte(input))

	return u, err

}

// String parse helpers.

var (

	urnPrefix  = []byte("urn:uuid:")

	byteGroups = []int{8, 4, 4, 4, 12}

)

// Nil is the nil UUID, as specified in RFC-4122, that has all 128 bits set to

// zero.

var Nil = UUID{}

// IsNil returns if the UUID is equal to the nil UUID.

func (u UUID) IsNil() bool {

	return u == Nil

}

// Version returns the algorithm version used to generate the UUID.

func (u UUID) Version() byte {

	return u[6] >> 4

}

func (u UUID) ValidVersion(versions ...byte) bool {

	if len(versions) == 0 {

		versions = []byte{1, 2, 3, 4, 5, 6, 7}

	}

	for _, version := range versions {

		if u.Version() == version {

			return true

		}

	}

	return false

}

// Variant returns the UUID layout variant.

func (u UUID) Variant() byte {

	switch {

	case (u[8] >> 7) == 0x00:

		return VariantNCS

	case (u[8] >> 6) == 0x02:

		return VariantRFC4122

	case (u[8] >> 5) == 0x06:

		return VariantMicrosoft

	case (u[8] >> 5) == 0x07:

		fallthrough

	default:

		return VariantFuture

	}

}

// UnmarshalText implements the encoding.TextUnmarshaler interface.

// Following formats are supported:

//

//	"6ba7b810-9dad-11d1-80b4-00c04fd430c8",

//	"{6ba7b810-9dad-11d1-80b4-00c04fd430c8}",

//	"urn:uuid:6ba7b810-9dad-11d1-80b4-00c04fd430c8"

//	"6ba7b8109dad11d180b400c04fd430c8"

//	"{6ba7b8109dad11d180b400c04fd430c8}",

//	"urn:uuid:6ba7b8109dad11d180b400c04fd430c8"

//

// ABNF for supported UUID text representation follows:

//

//	URN := 'urn'

//	UUID-NID := 'uuid'

//

//	hexdig := '0' | '1' | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9' |

//	          'a' | 'b' | 'c' | 'd' | 'e' | 'f' |

//	          'A' | 'B' | 'C' | 'D' | 'E' | 'F'

//

//	hexoct := hexdig hexdig

//	2hexoct := hexoct hexoct

//	4hexoct := 2hexoct 2hexoct

//	6hexoct := 4hexoct 2hexoct

//	12hexoct := 6hexoct 6hexoct

//

//	hashlike := 12hexoct

//	canonical := 4hexoct '-' 2hexoct '-' 2hexoct '-' 6hexoct

//

//	plain := canonical | hashlike

//	uuid := canonical | hashlike | braced | urn

//

//	braced := '{' plain '}' | '{' hashlike  '}'

//	urn := URN ':' UUID-NID ':' plain

func (u *UUID) UnmarshalText(text []byte) error {

	if len(text) < 32 {

		return ErrTooShort

	}

	if len(text) > 45 {

		return ErrTooLong

	}

	switch len(text) {

	case 32:

		return u.decodeHashLike(text)

	case 34, 38:

		return u.decodeBraced(text)

	case 36:

		return u.decodeCanonical(text)

	case 41, 45:

		return u.decodeURN(text)

	default:

		return fmt.Errorf("%w: incorrect UUID length %d in string %q", ErrInvalid, len(text), text)

	}

}

// decodeCanonical decodes UUID strings that are formatted as defined in RFC-4122 (section 3):

// "6ba7b810-9dad-11d1-80b4-00c04fd430c8".

// decodeHashLike decodes UUID strings that are using the following format:

//

//	"6ba7b8109dad11d180b400c04fd430c8".

func (u *UUID) decodeHashLike(t []byte) error {

	_, err := hex.Decode(u[:], t)

	return err

}

// decodeBraced decodes UUID strings that are using the following formats:

//

//	"{6ba7b810-9dad-11d1-80b4-00c04fd430c8}"

//	"{6ba7b8109dad11d180b400c04fd430c8}".

func (u *UUID) decodeBraced(t []byte) error {

	l := len(t)

	if t[0] != '{' || t[l-1] != '}' {

		return fmt.Errorf("%w: incorrect UUID format in string %q", ErrInvalid, t)

	}

	return u.decodePlain(t[1 : l-1])

}

// decodeURN decodes UUID strings that are using the following formats:

//

//	"urn:uuid:6ba7b810-9dad-11d1-80b4-00c04fd430c8"

//	"urn:uuid:6ba7b8109dad11d180b400c04fd430c8".

func (u *UUID) decodeURN(t []byte) error {

	total := len(t)

	urnUUIDPrefix := t[:9]

	if !bytes.Equal(urnUUIDPrefix, urnPrefix) {

		return fmt.Errorf("%w: incorrect UUID format in string %q", ErrInvalid, t)

	}

	return u.decodePlain(t[9:total])

}

// decodePlain decodes UUID strings that are using the following formats:

//

//	"6ba7b810-9dad-11d1-80b4-00c04fd430c8" or in hash-like format

//	"6ba7b8109dad11d180b400c04fd430c8".

func (u *UUID) decodePlain(t []byte) error {

	switch len(t) {

	case 32:

		return u.decodeHashLike(t)

	case 36:

		return u.decodeCanonical(t)

	default:

		return fmt.Errorf("%w: incorrect UUID length %d in string %q", ErrInvalid, len(t), t)

	}

}