muonsoft / validation

import (

	"errors"

	"github.com/muonsoft/validation/internal/uuid"

)

var (

	ErrTooShort               = errors.New("too short")

	ErrTooLong                = errors.New("too long")

	ErrTooLarge               = errors.New("too large")

	ErrInvalidCharacters      = errors.New("invalid characters")

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

	ErrInvalidVersion         = errors.New("invalid version")

	ErrIsNil                  = errors.New("is nil")

)

var ulidChars = newCharSet("0123456789ABCDEFGHJKMNPQRSTVWXYZabcdefghjkmnpqrstvwxyz")

// ULID validates whether the value is a valid ULID (Universally Unique Lexicographically Sortable Identifier).

// See https://github.com/ulid/spec for ULID specifications.

//

// Possible errors:

//   - [ErrTooShort] on values with length less than 26;

//   - [ErrTooLong] on values with length greater than 26;

//   - [ErrInvalidCharacters] on values with unexpected characters;

//   - [ErrTooLarge] on too big value (larger than '7ZZZZZZZZZZZZZZZZZZZZZZZZZ').

func ULID(value string) error {

	if len(value) < 26 {

		return ErrTooShort

	}

	if len(value) > 26 {

		return ErrTooLong

	}

	for _, c := range value {

		if !ulidChars.Contains(c) {

			return ErrInvalidCharacters

		}

	}

	// Largest valid ULID is '7ZZZZZZZZZZZZZZZZZZZZZZZZZ'

	// See https://github.com/ulid/spec#overflow-errors-when-parsing-base32-strings

	if value[0] > '7' {

		return ErrTooLarge

	}

	return nil

}

// UUID validates whether a string value is a valid UUID (also known as GUID).

//

// By default, it uses strict mode and checks the UUID as specified in RFC 4122.

// To parse additional formats, use the [AllowNonCanonicalUUIDFormats] option.

//

// In addition, it checks if the UUID version matches one of

// the registered versions: 1, 2, 3, 4, 5, 6 or 7.

// Use [AllowUUIDVersions] to validate for a specific set of versions.

//

// Nil UUID ("00000000-0000-0000-0000-000000000000") values are considered as valid.

// Use [DenyNilUUID] to disallow nil value.

//

// Possible errors:

//   - [ErrTooShort] on values with length less than 36 (or 32 for non-canonical formats);

//   - [ErrTooLong] on values with length greater than 36 (or 45 for non-canonical formats);

//   - [ErrInvalidCharacters] on values with unexpected characters;

//   - [ErrInvalidHyphenPlacement] on invalid placements of hyphens;

//   - [ErrInvalidVersion] on a restricted versions;

//   - [ErrIsNil] on nil value (if [DenyNilUUID] options is enabled);

//   - [ErrInvalid] on other cases;

//

// See http://tools.ietf.org/html/rfc4122.

func UUID(value string, options ...func(o *UUIDOptions)) error {

	opts := &UUIDOptions{}

	for _, set := range options {

		set(opts)

	}

	var (

		u   uuid.UUID

		err error

	)

	if opts.isNonStrict {

		u, err = uuid.FromString(value)

	} else {

		u, err = uuid.CanonicalFromString(value)

	}

	if err != nil {

		return convertUUIDError(err)

	}

	if !u.IsNil() && !u.ValidVersion(opts.versions...) {

		return ErrInvalidVersion

	}

	if opts.isNotNil && u.IsNil() {

		return ErrIsNil

	}

	return nil

}

// AllowNonCanonicalUUIDFormats used to enable parsing UUID value from non-canonical formats.

//

// 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".

func AllowNonCanonicalUUIDFormats() func(o *UUIDOptions) {

	return func(o *UUIDOptions) {

		o.isNonStrict = true

	}

}

// AllowUUIDVersions used to set valid versions of the UUID value.

// If the versions are empty, the UUID will be checked for compliance with the default

// registered versions: 1, 2, 3, 4, 5, 6 or 7.

func AllowUUIDVersions(versions ...byte) func(o *UUIDOptions) {

	return func(o *UUIDOptions) {

		o.versions = versions

	}

}

// DenyNilUUID used to treat nil UUID ("00000000-0000-0000-0000-000000000000") value as invalid.

}

// UUIDOptions are used to set up validation process of the [UUID] function.

type UUIDOptions struct {

	versions    []byte

	isNonStrict bool

	isNotNil    bool

}

//nolint:errorlint

func convertUUIDError(err error) error {

	switch err {

	case uuid.ErrTooShort:

		return ErrTooShort

	case uuid.ErrTooLong:

		return ErrTooLong

	case uuid.ErrInvalidHyphenPlacement:

		return ErrInvalidHyphenPlacement

	}

	return ErrInvalid

}

type charSet map[rune]struct{}

func (s charSet) Contains(c rune) bool {

	_, exist := s[c]

	return exist

}

func newCharSet(s string) charSet {

	chars := make(charSet, len(s))

	for _, c := range s {

		chars[c] = struct{}{}

	}

	return chars

}