ruby script to generate your dragon name, based on the rules in some meme image

dragon_name.rb

#!/usr/bin/env ruby
#
# Generate a dragon name based on this meme:
#   https://www.facebook.com/creepyshit01/photos/a.1037741526249418/2895913810432171
#
# Usage: ./dragon_name [<first_name>] [<last_name>] [<mothers_name>] [<fathers_name>]
#
# If you don't pass in any of the names, you will be prompted for them.

def prompt_for(text_prompt, min_length = 2)
    loop do
        STDOUT.print text_prompt + ': '
        STDOUT.flush

        input = gets.strip
        return input if input.length >= min_length

        puts "C'mon, you need to input SOMETHING..."
    end
end

first_name = ARGV[0] || prompt_for("Enter your first name")
last_name = ARGV[1] || prompt_for("Enter your last name")
mom_name = ARGV[2] || prompt_for("Your mother's first name")
dad_name = ARGV[3] || prompt_for("Your dad's first name")

dragon_name = ''

dragon_name += first_name[-2, 2]
dragon_name += last_name[last_name.length / 2, 2]
dragon_name += mom_name[0, 2].downcase
dragon_name += dad_name[-1]

puts ""
puts "Your dragon name is #{dragon_name.capitalize}"