Kata Berlin Clock

berlin-clock.rb

require 'minitest/autorun'

class BerlinClock

  def self.seconds(seconds)
    seconds.even? ? 'Y' : 'O'
  end

  def self.minutes(minutes)
    row1 = Array.new(11, 'O').unshift(['Y'] * (minutes / 5)).flatten.first(11)
    row2 = Array.new(4, 'O').unshift(['Y'] * (minutes % 5)).flatten.first(4)
    
    [2,5,8].each { |ix| row1[ix] = 'R' if row1[ix] == 'Y' }

    "#{row1.join('')} #{row2.join('')}"
  end

  def self.hours(hours)
    row1 = Array.new(4, 'O').unshift(['R'] * (hours / 5)).flatten.first(4)
    row2 = Array.new(4, 'O').unshift(['R'] * (hours % 5)).flatten.first(4)
    
    "#{row1.join('')} #{row2.join('')}"
  end

end

class String
  def to_berlin_clock
    hours, minutes, seconds = self.split(':').map &:to_i
    "#{BerlinClock.seconds(seconds)} #{BerlinClock.hours(hours)} #{BerlinClock.minutes(minutes)}"
  end
end


describe 'BerlinClock' do

  describe 'internals methods' do
    it 'seconds must to return Y/O' do
      BerlinClock.seconds(0).must_equal 'Y'
      BerlinClock.seconds(1).must_equal 'O'
      BerlinClock.seconds(28).must_equal 'Y'
      BerlinClock.seconds(57).must_equal 'O'
    end

    it 'hours must to return R/O in 2 rows' do
      BerlinClock.hours(0).must_equal  'OOOO OOOO'
      BerlinClock.hours(1).must_equal  'OOOO ROOO'
      BerlinClock.hours(13).must_equal 'RROO RRRO'
      BerlinClock.hours(16).must_equal 'RRRO ROOO'
    end

    it 'minutes must to return R/Y/O in the first row and Y/O in second one' do
      BerlinClock.minutes(0).must_equal  'OOOOOOOOOOO OOOO'
      BerlinClock.minutes(1).must_equal  'OOOOOOOOOOO YOOO'
      BerlinClock.minutes(13).must_equal 'YYOOOOOOOOO YYYO'
      BerlinClock.minutes(48).must_equal 'YYRYYRYYROO YYYO'
    end
  end
  
  it "must to represent the input time in berlin-clock form" do
    '00:00:00'.to_berlin_clock.must_equal 'Y OOOO OOOO OOOOOOOOOOO OOOO'
    '13:17:01'.to_berlin_clock.must_equal 'O RROO RRRO YYROOOOOOOO YYOO'
    '23:59:59'.to_berlin_clock.must_equal 'O RRRR RRRO YYRYYRYYRYY YYYY'
    '24:00:00'.to_berlin_clock.must_equal 'Y RRRR RRRR OOOOOOOOOOO OOOO'
  end
end