numbers_words

nums_to_words.rb

require 'pry'

class NumbersToWords
  def initialize
    @single = %w[zero one two three four five six seven eight nine ten elevin 
                twelve thirteen fourteen fifteen sixteen seventeen eighteen nineteen]
    @tens = %w[twenty thirty fourty fifty sixty seventy eighty ninety]
    @words = ""
  end
  
  def numbers_to_words(num)
    return if num < 1
    case 
      when num < 20 
        singles(num)
        num = 0
      when num < 100      && num >= 20
        tens(num)
        num -= reduce_num(num, 10)
      when num < 1000     && num >= 100
        hundreds(num)
        num -= reduce_num(num, 100)
      when num < 10000    && num >= 1000
        thousands(num)
        num -= reduce_num(num, 1000)
      when num < 100000   && num >= 10000
        tenthousands(num)
         num -=  reduce_num(num, 1000)
      when num < 1000000  && num >= 100000
        hundredthousands(num)
        num -=  reduce_num(num,1000 )
      when num < 10000000 && num >= 1000000 
        millions(num)
        num -= reduce_num(num, 1000000)
    end
    numbers_to_words(num)
    @words
  end
    
  def reduce_num(num, unit)
    (num / unit) * unit
  end
  
  def singles(i)
    @words += @single[i]
  end

   def tens(i)
     i /= 10
     i -= 2
     @words += @tens[i] + " "
   end
 
   def hundreds(i)
     i /= 100
     singles(i)
     @words += " hundred "
   end

   def thousands(i)
     i /= 1000
     singles(i)
     @words += " thousand "
   end

   def tenthousands(i)
     ten = i / 1000
     tens(ten)
     singles = ten % 10
     singles(singles) if singles > 0
     @words += " thousand "
    end
    
   def hundredthousands(i)
     hundred = i / 1000
     thousands = i / 10
     hundreds(hundred)
     tenthousands(thousands) if hundred % 100 > 0
     @words += " thousand " if hundred % 100 == 0
   end
   
  def millions(i)
    i /= 1000000
    singles(i) 
    @words += " million " 
  end
end

the_word = NumbersToWords.new
puts the_word.numbers_to_words(1498752)