use gfx;
use na;
use piston;
use view;
use vr;

pub trait Scene<D: gfx::Device,
                F: gfx::Factory<D::Resources>> {
  fn event(&mut self, event: Event);
  fn update(&mut self,
            vr: &mut Option<vr::VR>,  // TODO: abstract this out
            encoder: &mut gfx::Encoder<D::Resources, D::CommandBuffer>);
  fn render(&self,
            factory: &mut F,
            encoder: &mut gfx::Encoder<D::Resources, D::CommandBuffer>,
            trans: &gfx::handle::Buffer<D::Resources, view::Trans>,
            target: &gfx::handle::RenderTargetView<D::Resources, view::ColorFormat>,
            depth: &gfx::handle::DepthStencilView<D::Resources, view::DepthFormat>);

  fn origin(&self) -> na::Matrix4<f32>;
  fn mouselook(&self) -> na::Matrix4<f32>;
}

pub enum Event {
  Vr(vr::Event),
  Piston(piston::input::Input),
}