Contents

module Tapyrus
  # Base58Check encoding
  # https://en.bitcoin.it/wiki/Base58Check_encoding
  module Base58
    module_function

    ALPHABET = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
    SIZE = ALPHABET.size

    # encode hex value to base58 string.
    def encode(hex)
      leading_zero_bytes = (hex.match(/^([0]+)/) ? $1 : '').size / 2
      int_val = hex.to_i(16)
      base58_val = ''
      while int_val > 0
        int_val, remainder = int_val.divmod(SIZE)
        base58_val = ALPHABET[remainder] + base58_val
      end
      ('1' * leading_zero_bytes) + base58_val
    end

    # decode base58 string to hex value.
    def decode(base58_val)
      int_val = 0
      base58_val
        .reverse
        .split(//)
        .each_with_index do |char, index|
          raise ArgumentError, 'Value passed not a valid Base58 String.' if (char_index = ALPHABET.index(char)).nil?
          int_val += char_index * (SIZE**index)
        end
      s = int_val.to_even_length_hex
      s = '' if s == '00'
      leading_zero_bytes = (base58_val.match(/^([1]+)/) ? $1 : '').size
      s = ('00' * leading_zero_bytes) + s if leading_zero_bytes > 0
      s
    end
  end
end

Version data entries

10 entries across 10 versions & 1 rubygems

Version	Path
tapyrus-0.3.4	lib/tapyrus/base58.rb
tapyrus-0.3.3	lib/tapyrus/base58.rb
tapyrus-0.3.2	lib/tapyrus/base58.rb
tapyrus-0.3.1	lib/tapyrus/base58.rb
tapyrus-0.3.0	lib/tapyrus/base58.rb
tapyrus-0.2.13	lib/tapyrus/base58.rb
tapyrus-0.2.12	lib/tapyrus/base58.rb
tapyrus-0.2.10	lib/tapyrus/base58.rb
tapyrus-0.2.9	lib/tapyrus/base58.rb
tapyrus-0.2.8	lib/tapyrus/base58.rb