use crate::*;
impl<E: Engine> Audio for Sequencer<E> {
    fn process (&mut self, client: &Client, scope: &ProcessScope) -> Control {
        if let Some(ref transport) = self.transport {
            transport.write().unwrap().process(client, scope);
        }
        todo!("sequencer process")
    }
}

impl Phrase {
    /// Write a chunk of MIDI events to an output port.
    pub fn process_out (
        &self,
        output:   &mut PhraseChunk,
        notes_on: &mut [bool;128],
        timebase: &Arc<Timebase>,
        (frame0, frames, _): (usize, usize, f64),
    ) {
        let mut buf = Vec::with_capacity(8);
        for (time, tick) in Ticks(timebase.pulses_per_sample()).between_samples(
            frame0, frame0 + frames
        ) {
            let tick = tick % self.length;
            for message in self.notes[tick].iter() {
                buf.clear();
                let channel = 0.into();
                let message = *message;
                LiveEvent::Midi { channel, message }.write(&mut buf).unwrap();
                output[time as usize].push(buf.clone());
                match message {
                    MidiMessage::NoteOn  { key, .. } => notes_on[key.as_int() as usize] = true,
                    MidiMessage::NoteOff { key, .. } => notes_on[key.as_int() as usize] = false,
                    _ => {}
                }
            }
        }
    }
}
impl<E: Engine> PhrasePlayer<E> {
    pub fn process (
        &mut self,
        input:    Option<MidiIter>,
        timebase: &Arc<Timebase>,
        playing:  Option<TransportState>,
        started:  Option<(usize, usize)>,
        quant:    usize,
        reset:    bool,
        scope:    &ProcessScope,
        (frame0, frames): (usize, usize),
        (_usec0, _usecs): (usize, usize),
        period:   f64,
    ) {
        if self.midi_out.is_some() {
            // Clear the section of the output buffer that we will be using
            for frame in &mut self.midi_out_buf[0..frames] {
                frame.clear();
            }
            // Emit "all notes off" at start of buffer if requested
            if self.reset {
                all_notes_off(&mut self.midi_out_buf);
                self.reset = false;
            } else if reset {
                all_notes_off(&mut self.midi_out_buf);
            }
        }
        if let (
            Some(TransportState::Rolling),
            Some((start_frame, _)),
            Some((_started, Some(ref phrase)))
        ) = (playing, started, &self.phrase) {
            phrase.read().map(|phrase|{
                if self.midi_out.is_some() {
                    phrase.process_out(
                        &mut self.midi_out_buf,
                        &mut self.notes_out.write().unwrap(),
                        timebase,
                        (frame0.saturating_sub(start_frame), frames, period)
                    );
                }
            }).unwrap();
            let mut phrase = phrase.write().unwrap();
            let length = phrase.length;
            // Monitor and record input
            if input.is_some() && (self.recording || self.monitoring) {
                // For highlighting keys and note repeat
                let mut notes_in = self.notes_in.write().unwrap();
                for (frame, event, bytes) in parse_midi_input(input.unwrap()) {
                    match event {
                        LiveEvent::Midi { message, .. } => {
                            if self.monitoring {
                                self.midi_out_buf[frame].push(bytes.to_vec())
                            }
                            if self.recording {
                                phrase.record_event({
                                    let pulse = timebase.samples_to_pulse(
                                        (frame0 + frame - start_frame) as f64
                                    );
                                    let quantized = (
                                        pulse / quant as f64
                                    ).round() as usize * quant;
                                    let looped = quantized % length;
                                    looped
                                }, message);
                            }
                            match message {
                                MidiMessage::NoteOn { key, .. } => {
                                    notes_in[key.as_int() as usize] = true;
                                }
                                MidiMessage::NoteOff { key, .. } => {
                                    notes_in[key.as_int() as usize] = false;
                                },
                                _ => {}
                            }
                        },
                        _ => {}
                    }
                }
            }
        } else if input.is_some() && self.midi_out.is_some() && self.monitoring {
            let mut notes_in = self.notes_in.write().unwrap();
            for (frame, event, bytes) in parse_midi_input(input.unwrap()) {
                match event {
                    LiveEvent::Midi { message, .. } => {
                        self.midi_out_buf[frame].push(bytes.to_vec());
                        match message {
                            MidiMessage::NoteOn { key, .. } => {
                                notes_in[key.as_int() as usize] = true;
                            }
                            MidiMessage::NoteOff { key, .. } => {
                                notes_in[key.as_int() as usize] = false;
                            },
                            _ => {}
                        }
                    },
                    _ => {}
                }
            }
        }
        if let Some(out) = &mut self.midi_out {
            let writer = &mut out.writer(scope);
            let output = &self.midi_out_buf;
            for time in 0..frames {
                for event in output[time].iter() {
                    writer.write(&RawMidi { time: time as u32, bytes: &event })
                        .expect(&format!("{event:?}"));
                }
            }
        }
    }
}
/// Add "all notes off" to the start of a buffer.
pub fn all_notes_off (output: &mut PhraseChunk) {
    let mut buf = vec![];
    let msg = MidiMessage::Controller { controller: 123.into(), value: 0.into() };
    let evt = LiveEvent::Midi { channel: 0.into(), message: msg };
    evt.write(&mut buf).unwrap();
    output[0].push(buf);
}
/// Return boxed iterator of MIDI events
pub fn parse_midi_input (input: MidiIter) -> Box<dyn Iterator<Item=(usize, LiveEvent, &[u8])> + '_> {
    Box::new(input.map(|RawMidi { time, bytes }|(
        time as usize,
        LiveEvent::parse(bytes).unwrap(),
        bytes
    )))
}