a little tyiping tutor for curses

type.rb

%w(curses matrix).each { |lib| require lib }

class Range
  def any
    first + rand(last + (exclude_end? ? 0 : 1))
  end
end

module Indexable
  def any(len = nil)
    i = (0...size).any
    len ? self[i, len] : self[i]
  end
end

[String, Array].each { |c| c.module_eval { include Indexable } }

class TypingTutor
  COURSES = {
    :qwerty => %w(fj dk sl a; gh ty ru ei wo qp z/ x. c, vm bn
                  FJDKSLA:GHTYRUEIWOQPBNVMC<X>Z? 67 58 49 30
                  2- 1= ^& %* $( #) @_ !+ ]['\\` }{"|~),
    :dvorak => %w(uh et on as id yf pg .c ,r 'l ;z qv jw km xb
                  UHETONASIDYFPG>C<R"L:ZQVJWKMXB 67 58 49 30
                  2[ 1] ^& %* $( #) @{ !} =/-\\` +?_|~),
    :ag5    => %w(tn ei so ap vx jz fu d, w. qb yh lg km cr
                  TNEISOAPVXJZFUD;W:QBYHLGKMCR 12 34 56 78 90
                  =/ -* +@ #$ ~%"\' ^_!? &| <> `\\ []{}()),
  }
  
  def initialize window = Curses.init_screen
    @window = window
  end
  
  attr_accessor :line_pos
  
  def line= line
    @window.setpos(1, 0)
    @window << line
    line
  end
  
  def run course, line_length = 28
    Curses.noecho
    
    clean_lines = 0
    COURSES[course].inject do |chars, lesson|
      self.line = (1..line_length).inject('') do |m, i|
        m << if (2...line_length) === i && m[-1] != ?\s && rand < 0.25
          ?\s
        else
          (rand < 0.3 ? lesson : chars).tr(m[-1,1] || '', '').any
        end
      end
      
      @window.setpos(1, 0)
      error = false
      (1..line_length).each do |i|
        unless @window.getch == @window.inch
          Curses.beep
          error = true
          redo
        end
        @window.setpos(1, i)
      end
      
      Curses.beep until @window.getch == 32
      clean_lines = error ? 0 : clean_lines + 1
      clean_lines < 3 ? redo : clean_lines = 0
      chars << lesson
    end
  end
end

TypingTutor.new(Curses.init_screen).run(:qwerty) if __FILE__ == $0