tek/crates/tek_sequencer/src/sequencer.rs

use crate::*;
use tek_core::Direction;

/// Phrase editor.
pub struct Sequencer {
    pub name:      String,
    pub mode:      bool,
    pub focused:   bool,
    pub entered:   bool,

    pub phrase:    Option<Arc<RwLock<Phrase>>>,
    pub transport: Option<Arc<RwLock<TransportToolbar>>>,
    pub buffer:    BigBuffer,
    pub keys:      Buffer,
    /// Highlight input keys
    pub keys_in:  [bool; 128],
    /// Highlight output keys
    pub keys_out: [bool; 128],

    pub now:       usize,
    pub ppq:       usize,
    pub note_axis: FixedAxis<usize>,
    pub time_axis: ScaledAxis<usize>,
    /// Play input through output.
    pub monitoring: bool,
    /// Write input to sequence.
    pub recording:  bool,
    /// Overdub input to sequence.
    pub overdub:    bool,
    /// Map: tick -> MIDI events at tick
    pub phrases:    Vec<Arc<RwLock<Phrase>>>,
    /// Phrase selector
    pub sequence:   Option<usize>,
    /// Output from current sequence.
    pub midi_out:   Option<Port<MidiOut>>,
    /// MIDI output buffer
    midi_out_buf:   Vec<Vec<Vec<u8>>>,
    /// Send all notes off
    pub reset:      bool, // TODO?: after Some(nframes)
    /// Highlight keys on piano roll.
    pub notes_in:   [bool;128],
    /// Highlight keys on piano roll.
    pub notes_out:  [bool;128],
}

impl Sequencer {
    pub fn new (name: &str) -> Self {
        Self {
            name:         name.into(),
            monitoring:   false,
            recording:    false,
            overdub:      true,
            phrases:      vec![],
            sequence:     None,
            midi_out:     None,
            midi_out_buf: vec![Vec::with_capacity(16);16384],
            reset:        true,
            notes_in:     [false;128],
            notes_out:    [false;128],
            buffer:       Default::default(),
            keys:         keys_vert(),
            entered:      false,
            focused:      false,
            mode:         false,
            keys_in:      [false;128],
            keys_out:     [false;128],
            phrase:       None,
            now:          0,
            ppq:          96,
            transport:    None,
            note_axis: FixedAxis { start: 12, point: Some(36) },
            time_axis: ScaledAxis { start: 0, scale: 24, point: Some(0) },
        }
    }
    pub fn toggle_monitor (&mut self) {
        self.monitoring = !self.monitoring;
    }
    pub fn toggle_record (&mut self) {
        self.recording = !self.recording;
    }
    pub fn toggle_overdub (&mut self) {
        self.overdub = !self.overdub;
    }
    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(phrase)
        ) = (
            playing, started, self.sequence.and_then(|id|self.phrases.get_mut(id))
        ) {
            phrase.read().map(|phrase|{
                if self.midi_out.is_some() {
                    phrase.process_out(
                        &mut self.midi_out_buf,
                        &mut self.notes_out,
                        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
                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.frame_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, .. } => {
                                    self.notes_in[key.as_int() as usize] = true;
                                }
                                MidiMessage::NoteOff { key, .. } => {
                                    self.notes_in[key.as_int() as usize] = false;
                                },
                                _ => {}
                            }
                        },
                        _ => {}
                    }
                }
            }
        } else if input.is_some() && self.midi_out.is_some() && self.monitoring {
            for (frame, event, bytes) in parse_midi_input(input.unwrap()) {
                self.process_monitor_event(frame, &event, bytes)
            }
        }
        if let Some(out) = &mut self.midi_out {
            write_midi_output(&mut out.writer(scope), &self.midi_out_buf, frames);
        }
    }

    #[inline]
    fn process_monitor_event (&mut self, frame: usize, event: &LiveEvent, bytes: &[u8]) {
        match event {
            LiveEvent::Midi { message, .. } => {
                self.write_to_output_buffer(frame, bytes);
                self.process_monitor_message(&message);
            },
            _ => {}
        }
    }

    #[inline] fn write_to_output_buffer (&mut self, frame: usize, bytes: &[u8]) {
        self.midi_out_buf[frame].push(bytes.to_vec());
    }

    #[inline]
    fn process_monitor_message (&mut self, message: &MidiMessage) {
        match message {
            MidiMessage::NoteOn { key, .. } => {
                self.notes_in[key.as_int() as usize] = true;
            }
            MidiMessage::NoteOff { key, .. } => {
                self.notes_in[key.as_int() as usize] = false;
            },
            _ => {}
        }
    }
}