new-exercise

#!/usr/bin/env ruby

#TODO: modify project README to link new exercise

class ExerciseCreator
  README_TEMPLATE = File.join(Dir.pwd, 'WORKSHEET.md')

  def self.call
    new
      .make_exercise_root_dir
      .make_exercise_ruby_dir
      .copy_readme_template
  end

  def make_exercise_root_dir(path = directory_path)
    Dir.mkdir(path) unless Dir.exist?(path)

    self
  end

  def make_exercise_ruby_dir(path = File.join(directory_path, 'ruby'))
    Dir.mkdir(path) unless Dir.exist?(path)

    self
  end

  def copy_readme_template(path = File.join(directory_path, 'README.md'))
    File.write(path, IO.read(README_TEMPLATE).sub('Exercise Name', chapter_name))

    self
  end

  private

  def directory_path
    @directory_path ||= File.join(Dir.pwd, directory_name)
  end

  def directory_name
    @directory_name ||= "#{chapter_number.rjust(2, '0')}-#{chapter_name}"
  end

  def chapter_number
    @chapter_number ||= ARGV.fetch(0) do |_i|
      puts 'Exercise number?'
      gets.chomp
    end
  end

  def chapter_name
    @chapter_name ||= ARGV.fetch(1) do |_i|
      puts 'Exercise name?'
      gets.chomp.downcase.gsub(' ', '-')
    end
  end
end

ExerciseCreator.call if $0 == __FILE__