tabula rasa

src/sequence/midi.rs

@@ -0,0 +1,114 @@
+use crate::sequence::{Frame, Time};
+
+/// Pulses per quarter note
+pub const PPQ: usize = 96;
+
+pub struct Message {
+    bytes: Vec<u8>
+}
+
+pub struct MIDISequence {
+    name:   String,
+    length: usize,
+    events: Vec<(Frame, MIDIEvent)>,
+    notes:  Vec<u8>,
+}
+
+impl MIDISequence {
+    pub fn new (name: &str, length: usize) -> Self {
+        Self {
+            name: name.to_string(),
+            length,
+            events: vec![],
+            notes:  vec![],
+        }
+    }
+    pub fn add (&mut self, time: usize, event: MIDIEvent) -> &mut Self {
+        let mut sort = false;
+        match &event {
+            MIDIEvent::NoteOn(pitch, _velocity) => {
+                if !self.notes.contains(pitch) {
+                    self.notes.push(*pitch);
+                    sort = true;
+                }
+            }
+        }
+        if sort {
+            self.notes.sort();
+        }
+        self.events.push((time, event));
+        self
+    }
+    pub fn render (&self, stdout: &mut std::io::Stdout, resolution: usize)
+        -> Result<(), Box<dyn std::error::Error>>
+    {
+        use crossterm::{*, style::Stylize};
+        let (col, row) = cursor::position()?;
+        let unit = PPQ / resolution;
+        let length = self.length / unit;
+        let mut header = String::from("     ");
+        for i in 0..length {
+            if i % 8 == 0 {
+                header.push('┍');
+            } else {
+                header.push('━');
+            }
+        }
+        header.push('┑');
+        let mut tracks: Vec<(String, String)> = vec![];
+        for note in self.notes.iter().rev() {
+            let mut row_header = format!(" {note:3} ");
+            let mut row = String::new();
+            for beat in 0..length {
+                let mut active = false;
+                for (frame, event) in self.events.iter() {
+                    match event {
+                        MIDIEvent::NoteOn(pitch, _) => {
+                            if pitch == note
+                                && *frame >= beat * unit
+                                && *frame < (beat + 1) * unit
+                            {
+                                active = true;
+                                continue
+                            }
+                        }
+                    }
+                }
+                if active {
+                    row.push('⯀')
+                } else if beat == 0 {
+                    row.push('│');
+                } else if beat % 8 == 0 {
+                    row.push('┆');
+                } else {
+                    row.push('·');
+                }
+            }
+            tracks.push((row_header, row));
+        }
+        stdout.queue(style::PrintStyledContent(header.grey()))?;
+        for (row_header, row) in tracks.into_iter() {
+            stdout
+                .queue(cursor::MoveDown(1))?
+                .queue(cursor::MoveToColumn(col))?
+                .queue(style::PrintStyledContent(row_header.grey()))?
+                .queue(style::PrintStyledContent(row.clone().white()))?
+                .queue(style::PrintStyledContent(row.clone().yellow()))?
+                .queue(style::PrintStyledContent(row.white()))?;
+        }
+        //stdout
+            //.queue(cursor::MoveDown(1))?
+            //.queue(cursor::MoveToColumn(col))?
+            //.queue(style::PrintStyledContent(footer.grey()))?;
+            //.queue(style::PrintStyledContent("················".grey()))?
+            //.queue(style::PrintStyledContent("│".yellow()))?
+            //.queue(cursor::MoveDown(1))?
+            //.queue(cursor::MoveLeft(18))?
+            //.queue(style::PrintStyledContent("└────────────────┘".yellow()))?;
+        Ok(())
+    }
+}
+
+pub enum MIDIEvent {
+    NoteOn(u8, u8)
+}