# <!-- rdoc-file=lib/base64.rb -->
# The Base64 module provides for the encoding (#encode64, #strict_encode64,
# #urlsafe_encode64) and decoding (#decode64, #strict_decode64,
# #urlsafe_decode64) of binary data using a Base64 representation.
#
# ## Example
#
# A simple encoding and decoding.
#
#     require "base64"
#
#     enc   = Base64.encode64('Send reinforcements')
#                         # -> "U2VuZCByZWluZm9yY2VtZW50cw==\n"
#     plain = Base64.decode64(enc)
#                         # -> "Send reinforcements"
#
# The purpose of using base64 to encode data is that it translates any binary
# data into purely printable characters.
#
module Base64
  # <!--
  #   rdoc-file=lib/base64.rb
  #   - decode64(str)
  # -->
  # Returns the Base64-decoded version of `str`. This method complies with RFC
  # 2045. Characters outside the base alphabet are ignored.
  #
  #     require 'base64'
  #     str = 'VGhpcyBpcyBsaW5lIG9uZQpUaGlzIG' +
  #           'lzIGxpbmUgdHdvClRoaXMgaXMgbGlu' +
  #           'ZSB0aHJlZQpBbmQgc28gb24uLi4K'
  #     puts Base64.decode64(str)
  #
  # *Generates:*
  #
  #     This is line one
  #     This is line two
  #     This is line three
  #     And so on...
  #
  def self?.decode64: (String str) -> String

  # <!--
  #   rdoc-file=lib/base64.rb
  #   - encode64(bin)
  # -->
  # Returns the Base64-encoded version of `bin`. This method complies with RFC
  # 2045. Line feeds are added to every 60 encoded characters.
  #
  #     require 'base64'
  #     Base64.encode64("Now is the time for all good coders\nto learn Ruby")
  #
  # *Generates:*
  #
  #     Tm93IGlzIHRoZSB0aW1lIGZvciBhbGwgZ29vZCBjb2RlcnMKdG8gbGVhcm4g
  #     UnVieQ==
  #
  def self?.encode64: (String bin) -> String

  # <!--
  #   rdoc-file=lib/base64.rb
  #   - strict_decode64(str)
  # -->
  # Returns the Base64-decoded version of `str`. This method complies with RFC
  # 4648. ArgumentError is raised if `str` is incorrectly padded or contains
  # non-alphabet characters.  Note that CR or LF are also rejected.
  #
  def self?.strict_decode64: (String str) -> String

  # <!--
  #   rdoc-file=lib/base64.rb
  #   - strict_encode64(bin)
  # -->
  # Returns the Base64-encoded version of `bin`. This method complies with RFC
  # 4648. No line feeds are added.
  #
  def self?.strict_encode64: (String bin) -> String

  # <!--
  #   rdoc-file=lib/base64.rb
  #   - urlsafe_decode64(str)
  # -->
  # Returns the Base64-decoded version of `str`. This method complies with ``Base
  # 64 Encoding with URL and Filename Safe Alphabet'' in RFC 4648. The alphabet
  # uses '-' instead of '+' and '_' instead of '/'.
  #
  # The padding character is optional. This method accepts both correctly-padded
  # and unpadded input. Note that it still rejects incorrectly-padded input.
  #
  def self?.urlsafe_decode64: (String str) -> String

  # <!--
  #   rdoc-file=lib/base64.rb
  #   - urlsafe_encode64(bin, padding: true)
  # -->
  # Returns the Base64-encoded version of `bin`. This method complies with ``Base
  # 64 Encoding with URL and Filename Safe Alphabet'' in RFC 4648. The alphabet
  # uses '-' instead of '+' and '_' instead of '/'. Note that the result can still
  # contain '='. You can remove the padding by setting `padding` as false.
  #
  def self?.urlsafe_encode64: (String bin, ?padding: boolish) -> String
end