class RuboCop::Cop::Style::OperatorMethodCall

def insert_space_after?(node)
  rhs = node.first_argument
  selector = node.loc.selector
  return true if selector.end_pos == rhs.source_range.begin_pos
  return false if node.parent&.call_type? # if chained, a space is already added
  # For `/` operations, if the RHS starts with a `(` without space,
  # add one to avoid a syntax error.
  range = selector.end.join(rhs.source_range.begin)
  return true if node.method?(:/) && range.source == '('
  false
end

def invalid_syntax_argument?(argument)
  type = argument.hash_type? ? argument.children.first&.type : argument.type
  INVALID_SYNTAX_ARG_TYPES.include?(type)
end

def method_call_with_parenthesized_arg?(argument)
  return false unless argument.parent.parent&.send_type?
  argument.children.first && argument.parent.parenthesized?
end

def on_send(node)
  return unless (dot = node.loc.dot)
  return if node.receiver.const_type? || !node.arguments.one?
  return unless (rhs = node.first_argument)
  return if method_call_with_parenthesized_arg?(rhs)
  return if invalid_syntax_argument?(rhs)
  add_offense(dot) do |corrector|
    wrap_in_parentheses_if_chained(corrector, node)
    corrector.replace(dot, ' ')
    selector = node.loc.selector
    corrector.insert_after(selector, ' ') if insert_space_after?(node)
  end
end

def wrap_in_parentheses_if_chained(corrector, node)
  return unless node.parent&.call_type?
  return if node.parent.first_argument == node
  operator = node.loc.selector
  ParenthesesCorrector.correct(corrector, node)
  corrector.insert_after(operator, ' ')
  corrector.wrap(node, '(', ')')
end