gistfile1.rb

class DecimalStringComparer
  def self.compare_decimal(a, b)
    new(a, b).execute
  end

  def initialize(a, b)
   @a = a
   @b = b
  end

  def execute
    @a, @b = @a.split("."), @b.split(".")
    until a.empty? && b.empty?
      result = compare(a.shift, b.shift)
      return result if result != 0
    end
    0
  end

  def compare
    case
    when a.nil?
      -1
    when b.nil?
      1
    when is_integer?(a) && is_integer?(b)
      a.to_i <=> b.to_i
    when is_integer?(a)
      1
    when is_integer?(b)
      -1
    else
      a <=> b
    end
  end

  def is_integer?(n)
    n.to_s.to_i.to_s == n.to_s
  end
end