require 'rspec'
require 'roll'

describe Roll do

  let(:rand_generator) do
    rand_generator = double('rand_gen').as_null_object
    rand_generator.stub(:rand).and_return(1,2,3,4,5,6,7,8,9,10)
    rand_generator
  end

  before(:each) do
    unless Roll.respond_to?(:size)
      class Roll
        def size
          @dice.count
        end
      end
    end
  end

  describe "roll" do
    it "should have <parameters> elements" do
      roll = Roll.new(2, rand_generator)
      roll.should have(2).items
    end

    it "returns a list of numbers" do
      roll = Roll.new(10, rand_generator)
      roll.should == [1,2,3,4,5,6,7,8,9,10]
    end

    it "calls Random once for each call" do
      Random.should_receive(:rand).exactly(5)
      roll = Roll.new(5)
    end

    it "calls Random with default value of 10 when no options provided" do
      Random.should_receive(:rand).with(10).exactly(5)
      roll = Roll.new(5)
    end
  end

  describe "reroll" do
    it "rerolls all dice that match the parameter" do
      roll = Roll.new(5, rand_generator)
      roll.reroll(3).should == [1,2,6,4,5]
    end

    it "rerolls all dice that match any of the parameters" do
      roll = Roll.new(5, rand_generator)
      roll.reroll(3,4).should == [1,2,6,7,5]
    end

    it "applies until it can't" do
      rand_generator = double('rand_gen').as_null_object
      rand_generator.stub(:rand).and_return(1,1,1,4)
      roll = Roll.new(1, rand_generator)
      roll.reroll(1).should == [4]
    end
  end

  describe "explode" do
    it "adds die to the result of all dice that match the parameter" do
      roll = Roll.new(5, rand_generator)
      roll.explode(3).should == [1,2,9,4,5]
    end

    it "adds die to the result of all dice that match any of the parameters" do
      roll = Roll.new(5, rand_generator)
      roll.explode(3,4).should == [1,2,9,11,5]
    end

    it "applies until it can't" do
      rand_generator = double('rand_gen').as_null_object
      rand_generator.stub(:rand).and_return(10,10,10,9)
      roll = Roll.new(1, rand_generator)
      roll.explode(10).should == [39]
    end
  end

end