module Puppet::Parser::Functions

  newfunction(:base64, :type => :rvalue, :doc => <<-'ENDHEREDOC') do |args|

    Base64 encode or decode a string based on the command and the string submitted

    Usage:

      $encodestring = base64('encode', 'thestring')
      $decodestring = base64('decode', 'dGhlc3RyaW5n')

      # explicitly define encode/decode method: default, strict, urlsafe
      $method = 'default'
      $encodestring = base64('encode', 'thestring', $method)
      $decodestring = base64('decode', 'dGhlc3RyaW5n', $method)

    ENDHEREDOC

    require 'base64'

    raise Puppet::ParseError, ("base64(): Wrong number of arguments (#{args.length}; must be >= 2)") unless args.length >= 2

    actions = ['encode','decode']

    unless actions.include?(args[0])
      raise Puppet::ParseError, ("base64(): the first argument must be one of 'encode' or 'decode'")
    end

    unless args[1].is_a?(String)
      raise Puppet::ParseError, ("base64(): the second argument must be a string to base64")
    end

    method = ['default','strict','urlsafe']

    if args.length <= 2
      chosenMethod = 'default'
    else
      chosenMethod = args[2]
    end

    unless method.include?(chosenMethod)
      raise Puppet::ParseError, ("base64(): the third argument must be one of 'default', 'strict', or 'urlsafe'")
    end

    case args[0]
      when 'encode'
        case chosenMethod
          when 'default'
            result = Base64.encode64(args[1])
          when 'strict'
            result = Base64.strict_encode64(args[1])
          when 'urlsafe'
            result = Base64.urlsafe_encode64(args[1])
        end
      when 'decode'
        case chosenMethod
          when 'default'
            result = Base64.decode64(args[1])
          when 'strict'
            result = Base64.strict_decode64(args[1])
          when 'urlsafe'
            result = Base64.urlsafe_decode64(args[1])
        end
    end

    return result
  end
end