module ElasticAPM::SpanHelpers::ClassMethods

def __span_method_on(klass, method, name = nil, type = nil)
  name ||= method.to_s
  type ||= Span::DEFAULT_TYPE
  klass.class_eval <<-RUBY, __FILE__, __LINE__ + 1
    alias :"__without_apm_#{method}" :"#{method}"
    def #{method}(*args, &block)
      unless ElasticAPM.current_transaction
        return __without_apm_#{method}(*args, &block)
      end
      ElasticAPM.span "#{name}", "#{type}" do
        __without_apm_#{method}(*args, &block)
      end
    end
  RUBY
end

def span_class_method(method, name = nil, type = nil)
  __span_method_on(singleton_class, method, name, type)
end

def span_method(method, name = nil, type = nil)
  __span_method_on(self, method, name, type)
end