如何在模型中使用Laravel DI？

I have an Eloquent model object: $user, of class User.

I want to make a method inside this model:

function sayHello($target)
{
    $this->hello = MegaFacede::launch();
}

Facades are not IDE friendly, so I get services from the container:

function sayHello($target)
{
    /** @var Mega $mega */
    $mega = App::make('mega');
    $this->hello = $mega->launch();
}

But how can I inject $mega instance to this object?