Class: Base32::Electrologica

Inherits:
Object
  • Object
show all
Defined in:
lib/base32-alphabets/electrologica.rb

Overview

Base32 (2^5 - 5-bits)

Constant Summary collapse

ALPHABET = 
%w[ 00 01 02 03 04 05 06 07
08 09 10 11 12 13 14 15
16 17 18 19 20 21 22 23
24 25 26 27 28 29 30 31 ]
NUMBER =

Note:

for decoding allow (misspelled) l/L for 1
 and               (misspelled)  0  for o/O - why? why not?
 and UPPERCASE letters - why? why not?

{    ## rename INTEGER /INT - why? why not??

  '00' => 0,  '0' => 0,
  '01' => 1,  '1' => 1,
  '02' => 2,  '2' => 2,
  '03' => 3,  '3' => 3,
  '04' => 4,  '4' => 4,
  '05' => 5,  '5' => 5,
  '06' => 6,  '6' => 6,
  '07' => 7,  '7' => 7,
  '08' => 8,  '8' => 8,
  '09' => 9,  '9' => 9,
  '10' => 10,
  '11' => 11,
  '12' => 12,
  '13' => 13,
  '14' => 14,
  '15' => 15,
  '16' => 16,
  '17' => 17,
  '18' => 18,
  '19' => 19,
  '20' => 20,
  '21' => 21,
  '22' => 22,
  '23' => 23,
  '24' => 24,
  '25' => 25,
  '26' => 26,
  '27' => 27,
  '28' => 28,
  '29' => 29,
  '30' => 30,
  '31' => 31,
}
NUM =

add shortcuts (convenience) aliases BIN = BINARY

NUMBER

Class Method Summary collapse

Class Method Details

.decode(str) ⇒ Object

Converts a base32 string to a base10 integer.



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# File 'lib/base32-alphabets/electrologica.rb', line 71

def self.decode( str )
  ## note: allow spaces or slash (/) for dashes (-)

  str = str.strip  ## remove leading and trailing spaces (first)

  str = str.tr( ' /', '-' )
  str = str.gsub( /-{2,}/, '-' )  ## fold more than one dash into one


  num = 0
  str.split('-').reverse.each.with_index do |char,index|
    code = NUMBER[char]
    raise ArgumentError, "Value passed not a valid base32 string - >#{char}< not found in alphabet"  if code.nil?
    num += code * (BASE**(index))
  end
  num
end

.encode(num) ⇒ Object

Converts a base10 integer to a base32 string.



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# File 'lib/base32-alphabets/electrologica.rb', line 12

def self.encode( num )
  buf = String.new
  while num >= BASE
    # puts "num=#{num}"

    mod = num % BASE
    # puts "  mod=#{mod} == #{ALPHABET[mod]}"

    buf = "-" + ALPHABET[mod] + buf    ## note: add - separator

    # puts "buf=#{buf}"

    num = (num - mod)/BASE
  end
  ALPHABET[num] + buf
end

.fmt(str, sep: '-') ⇒ Object 



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# File 'lib/base32-alphabets/electrologica.rb', line 87

def self.fmt( str, sep: '-' )
  ## note: allow spaces or slash (/) for dashes (-)

  str = str.strip  ## remove leading and trailing spaces (first)

  str = str.tr( ' /', '-' )
  str = str.gsub( /-{2,}/, '-' )  ## fold more than one dash into one


  ## format in groups of four (4) separated by space

  ##  e.g.  ccac7787fa7fafaa16467755f9ee444467667366cccceede

  ##     :  ccac 7787 fa7f afaa 1646 7755 f9ee 4444 6766 7366 cccc eede


  ## note: use reverse - if not divided by four that leading slice gets cut short

  str.split('-').reverse.each_slice(4).map { |slice| slice.reverse.join( sep ) }.reverse.join( ' ' )
end