# Double Dispatch with a 3 by 3 matrix
class Rock
  def fight other
    other.fightWithRock self
  end
  def fightWithRock other
    "Tie"
  end
  def fightWithPaper other
    "Paper wins"
  end
  def fightWithScissors other
    "Rock wins"
  end
end

class Paper
  def fight other
    other.fightWithPaper self
  end
  def fightWithRock other
    "Paper wins"
  end
  def fightWithPaper other
    "Tie"
  end
  def fightWithScissors other
    "Scissors wins"
  end
end

class Scissors
  def fight other
    other.fightWithScissors self
  end
  def fightWithRock other
    "Rock wins"
  end
  def fightWithPaper other
    "Scissors wins"
  end
  def fightWithScissors other
    "Tie"
  end
end

Rock.new.fight(Scissors.new)

# Exercise: Which cell is being filled in the table with the following calls? Recall:
#                     [Class 1]
#                    R     P      S
#          R     |      |      |     |
#[Class 2] P     |      |      |     | 
#          S     |      |      |     | 
#
# Assume "Class 1" is "self" (object you're sending a message to) and "Class 2" is the parameter)

# print Rock.new.fight(Scissors.new) --> X
# print Scissors.new.fight(Rock.new) --> Y
# print Paper.new.fight(Paper.new) --> Z

# How would we evaluate this if we were an interpreter? 

# Simple Double Dispatch example
class A
  def f x
    x.fWithA self
  end
  def fWithA a
    "(a, a) case"
  end
  def fWithB b
    "(b, a) case"
  end
end

class B
  def f x
    x.fWithB self
  end
  def fWithA a
    "(a, b) case"
  end
  def fWithB b
    "(b, b) case"
  end
end

# print A.new.f(A.new) + " "
# print A.new.f(B.new) + " "
# print B.new.f(A.new) + " "
# print B.new.f(B.new) + "\n"

# Visitor version!

class RockV
  def accept(visitor)
    visitor.visitRock(self)
  end
  
  def visitRock(rock)
    "Tie"
  end

  def visitScissors(scissors)
    "Rock Wins"
  end

  def visitPaper(paper)
    "Paper Wins"
  end
end

class PaperV
  def accept(visitor)
    visitor.visitPaper(self)
  end
  
  def visitRock(rock)
    "Tie"
  end
  
  def visitScissors(scissors)
    "Scissors Wins"
  end

  def visitPaper(paper)
    "Paper Wins"
  end
end

class ScissorsV
  def accept(visitor)
    visitor.visitScissors(self)
  end

  def visitRock(rock)
    "Rock Wins"
  end

  def visitScissors(scissors)
    "Tie"
  end

  def visitPaper(paper)
    "Scissors Wins"
  end
end

class Stringer

  def visitRock(rock)
    "Print -> Rock"
  end

  def visitScissors(scissors)
    "Print -> Scissors"
  end
  
  def visitPaper(paper)
    "Print -> Paper"
  end  

end