class RuboCop::Cop::Style::Not

def autocorrect(node)
  range = range_with_surrounding_space(node.loc.selector, :right)
  child = node.children.first
  if opposite_method?(child)
    correct_opposite_method(range, child)
  elsif requires_parens?(child)
    correct_with_parens(range, node)
  else
    correct_without_parens(range)
  end
end

def correct_opposite_method(range, child)
  lambda do |corrector|
    corrector.remove(range)
    corrector.replace(child.loc.selector,
                      OPPOSITE_METHODS[child.method_name].to_s)
  end
end

def correct_with_parens(range, node)
  lambda do |corrector|
    corrector.replace(range, '!(')
    corrector.insert_after(node.source_range, ')')
  end
end

def correct_without_parens(range)
  ->(corrector) { corrector.replace(range, '!') }
end

def on_send(node)
  return unless node.keyword_not?
  add_offense(node, :selector)
end

def opposite_method?(child)
  child.send_type? && OPPOSITE_METHODS.key?(child.method_name)
end

def requires_parens?(child)
  child.and_type? || child.or_type? || child.binary_operation? ||
    child.if_type? && child.ternary?
end