encoding.go

// Copyright 2014 Gyepi Sam. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package mcf

// An Encoding is a number for an encoder and is used to disambiguate amongst the various encoders.
// Not all encoders will be implemented, installed, or used in any given system.
type Encoding uint8

// List of known encodings.
const (
	BCRYPT Encoding = iota // import "github.com/gyepisam/mcf/bcrypt"
	SCRYPT                 // import "github.com/gyepisam/mcf/scrypt"
	PBKDF2                 // import "github.com/gyepisam/mcf/pbkdf2"
	//CRYPT                       // Not implemented yet

	maxEncoding
)

// if you add an encoding above, name it below!

func (e Encoding) String() string {
	switch e {
	case BCRYPT:
		return "bcrypt"
	case SCRYPT:
		return "scrypt"
	case PBKDF2:
		return "pbkdf2"
		/*	case CRYPT:
			return "crypt" */
	}
	return "unknown"
}

// IsValid returns true if the encoding is known.
func (e Encoding) IsValid() bool {
	return e >= 0 && e < maxEncoding
}

// ErrUnregisteredEncoding is returned when an unregistered encoding is encountered.
type ErrUnregisteredEncoding struct{ s string }

func (e *ErrUnregisteredEncoding) Error() string { return e.s }

// ErrInvalidEncoding is returned when an invalid encoding is encountered.
type ErrInvalidEncoding struct{ s string }

func (e *ErrInvalidEncoding) Error() string { return e.s }

func (e Encoding) errInvalid() error {
	return &ErrInvalidEncoding{"invalid encoding: " + string(e)}
}