Module: Tapyrus::Base58

Defined in:
lib/tapyrus/base58.rb

Overview

Base58Check encoding en.bitcoin.it/wiki/Base58Check_encoding

Constant Summary collapse

ALPHABET = 
"123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"
SIZE = 
ALPHABET.size

Class Method Summary collapse

Class Method Details

.decode(base58_val) ⇒ Object

decode base58 string to hex value.



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# File 'lib/tapyrus/base58.rb', line 23

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

.encode(hex) ⇒ Object

encode hex value to base58 string.



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# File 'lib/tapyrus/base58.rb', line 11

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