class Dentaku::AST::Modulo

def self.arity
  @arity
end

def self.peek(input)
  @arity = 1
  @arity = 2 if input.length > 1
end

def self.precedence
  20
end

def dependencies(context = {})
  if percent?
    @right.dependencies(context)
  else
    super
  end
end

def initialize(left, right = nil)
  if right
    @left  = left
    @right = right
  else
    @right = left
  end
  unless valid_left?
    raise NodeError.new(%i[numeric nil], left.type, :left),
          "#{self.class} requires numeric operands or nil"
  end
  unless valid_right?
    raise NodeError.new(:numeric, right.type, :right),
          "#{self.class} requires numeric operands"
  end
end

def operator
  :%
end

def percent?
  left.nil?
end

def valid_left?
  valid_node?(left) || left.nil?
end

def value(context = {})
  if percent?
    cast(right.value(context)) * 0.01
  else
    super
  end
end