readable.go

package base256

import (
	utls "github.com/cyrildever/go-utls/common/utils"
)

// Based on the 512-characters UTF-8 table - @see https://www.utf8-chartable.de/unicode-utf8-table.pl?number=512
var CHARSET = []rune("!\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^`abcdefghijklmnopqrstuvwxyz{|}€¡¢£¤¥¦§¨©ª«¬®¯°±²³´µ¶·¸¹»¼½¾¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝÞßàáâãäåæçèéêëìíîïðñòóôõö÷ùúûüýÿăąĊčđĕĘğħĩĭıĵķĿŀŁłňŋŏœŖřŝşŦŧũūůŲŵſƀƁƂƄƆƇƔƕƗƙƛƜƟƢƥƦƧƩƪƭƮưƱƲƵƸƺƾǀǁǂƿǬǮǵǶǹǻǿ")

//--- TYPES

// Readable represents a character in a readable base-256 charset
type Readable string

//--- METHODS

// Bytes ...
func (b256 Readable) Bytes() []byte {
	var barray []byte
	for _, char := range b256 {
		barray = append(barray, byte(IndexOf(char)))
	}
	return barray
}

// IsEmpty ...
func (b256 Readable) IsEmpty() bool {
	return b256.String() == ""
}

// Len ...
func (b256 Readable) Len() int {
	length := 0
	for range b256 {
		length++
	}
	return length
}

// NonEmpty ...
func (b256 Readable) NonEmpty() bool {
	return !b256.IsEmpty()
}

// String ...
func (b256 Readable) String() string {
	return string(b256)
}

// ToHex ...
func (b256 Readable) ToHex() string {
	return utls.ToHex(b256.Bytes())
}

//--- FUNCTION

// CharAt returns the character string at the passed index in the Base-256 character set
func CharAt(index int) string {
	return string(CHARSET[index : index+1])
}

// IndexOf ...
func IndexOf(char rune) int {
	for i, r := range CHARSET {
		if r == char {
			return i
		}
	}
	return -1
}

// ToBase256Readable ...
func ToBase256Readable(barray []byte) Readable {
	str := ""
	for _, b := range barray {
		str += CharAt(int(b))
	}
	return Readable(str)
}

// HexToReadable ...
func HexToReadable(hex string) (b256 Readable, err error) {
	bytes, err := utls.FromHex(hex)
	if err != nil {
		return
	}
	b256 = ToBase256Readable(bytes)
	return
}