#!/usr/bin/ruby

# start timer
# rand rand rand(+-*)
# compter bonnes et mauvaises reponses

class Quizzer
	OPERATIONS = [:+, :-, :*, :/]

	attr_reader :bad_ans, :history
	def initialize(posonly = false)
		@posonly = posonly
		@history = []
	end
	
	def quizz
		op = OPERATIONS[rand(OPERATIONS.length)]
		
		op1 = 1+rand(10)
		op2 = 1+rand(10)

		case op
		when :/
			op1 *= op2
		when :-
			op1, op2 = op2, op1 if @posonly and op2 > op1
		end

		str = "#{op1} #{op} #{op2}"
		@history << str
		puts str
		ans = gets.to_i

		if ans != op1.send(op, op2)
			@bad_ans += 1
			puts 'NOK'
		else
			puts 'OK'
		end
		puts
	end

	def time_quizz(nr)
		tstart = Time.now
		@bad_ans = 0
		nr.times { quizz }
		tend = Time.now

		puts "resultat:", " erreurs: #@bad_ans sur #{nr}", " duree: #{'%.1f' % (tend - tstart)}s"
	end	
end

if __FILE__ == $0
	q = Quizzer.new(ARGV.shift == 'positive')
	puts 'Appuyez sur [entree]'
	gets
	q.time_quizz(10)
end