generate

#!/usr/bin/env ruby
require 'optparse'
require 'tempfile'
require_relative '../generatorv2/lib/generator'

# Helper methods
def exercises
  Dir.entries('./exercises/practice')
    .select { |file| File.directory? File.join('./exercises/practice', file) }
end

def underscore(str)
  str.gsub(/[^\w\s-]/, '').gsub(/[-\s]/, '_').downcase
end

class VerificationError < StandardError
  MESSAGE = 'The result generated for %<exercise>s, does not match the current file'

  def initialize(message = MESSAGE)
    super
  end
end

# Parsing Code
parser = OptionParser.new

parser.on('-v', '--version', 'Print the version') do
  puts File.read('./generatorv2/VERSION')
end

parser.on('-h', '--help', 'Prints help') do
  puts parser
end

parser.on('-a', '--all', 'Generate all exercises') do
  exercises.each do |exercise|
    if File.exist?("./exercises/practice/#{exercise}/.meta/test_template.erb")
      Generator.new(exercise).generate
    end
  end
end

parser.on('--verify', 'Verify all exercises') do
  exercises.each do |exercise|
    if File.exist?("./exercises/practice/#{exercise}/.meta/test_template.erb")
      current_code = File.read("./exercises/practice/#{exercise}/#{underscore(exercise)}_test.rb")
      f = File.new("./exercises/practice/#{exercise}/temp_test.rb", 'w+')
      Generator.new(exercise).generate(f.path)
      generated_code = f.read
      File.delete(f.path)
      fail VerificationError unless current_code == generated_code
    end
    rescue VerificationError => e
      STDERR.puts e.message % {exercise:}
  end
end

parser.on('-e', '--exercise EXERCISE', 'The exercise to generate') do |exercise|
  Generator.new(exercise).generate
end

parser.parse!