use crate::*;
impl<E: Engine> Audio for TransportToolbar<E> {
    fn process (&mut self, _: &Client, scope: &ProcessScope) -> Control {
        self.update(&scope);
        Control::Continue
    }
}
impl<E: Engine> TransportToolbar<E> {
    pub fn update (&mut self, scope: &ProcessScope) -> (bool, usize, usize, usize, usize, f64) {
        let times      = scope.cycle_times().unwrap();
        let CycleTimes { current_frames, current_usecs, next_usecs, period_usecs } = times;
        let chunk_size = scope.n_frames() as usize;
        let transport  = self.transport.as_ref().unwrap().query().unwrap();
        self.frame     = transport.pos.frame() as usize;
        let mut reset  = false;
        if self.playing != Some(transport.state) {
            match transport.state {
                TransportState::Rolling => {
                    self.started = Some((current_frames as usize, current_usecs as usize));
                },
                TransportState::Stopped => {
                    self.started = None;
                    reset = true;
                },
                _ => {}
            }
        }
        self.playing = Some(transport.state);
        if self.playing == Some(TransportState::Stopped) {
            self.started = None;
        }
        match self.started {
            Some((_, usecs)) => {
                self.usecs = current_usecs as usize - usecs;
            },
            None => {
                self.usecs = 0;
            }
        }
        (
            reset,
            current_frames as usize,
            chunk_size as usize,
            current_usecs as usize,
            next_usecs as usize,
            period_usecs as f64
        )
    }
}