use clap::ArgMatches as Args; use helix_core::{indent::TAB_WIDTH, state::Mode, syntax::HighlightEvent, Range, State}; use helix_view::{commands, keymap, View}; use std::{ borrow::Cow, io::{self, stdout, Write}, path::PathBuf, time::Duration, }; use smol::prelude::*; use anyhow::Error; use crossterm::{ cursor, cursor::position, event::{self, read, Event, EventStream, KeyCode, KeyEvent}, execute, queue, style::{Color, Print, SetForegroundColor}, terminal::{self, disable_raw_mode, enable_raw_mode}, }; use tui::{backend::CrosstermBackend, buffer::Buffer as Surface, layout::Rect, style::Style}; type Terminal = tui::Terminal>; static EX: smol::Executor = smol::Executor::new(); pub struct Editor { terminal: Terminal, view: Option, size: (u16, u16), surface: Surface, cache: Surface, } impl Editor { pub fn new(mut args: Args) -> Result { let backend = CrosstermBackend::new(stdout()); let mut terminal = Terminal::new(backend)?; let size = terminal::size().unwrap(); let area = Rect::new(0, 0, size.0, size.1); let mut editor = Editor { terminal, view: None, size, surface: Surface::empty(area), cache: Surface::empty(area), }; if let Some(file) = args.values_of_t::("files").unwrap().pop() { editor.open(file)?; } Ok(editor) } pub fn open(&mut self, path: PathBuf) -> Result<(), Error> { self.view = Some(View::open(path, self.size)?); Ok(()) } fn render(&mut self) { use tui::backend::Backend; use tui::style::Color; // TODO: ideally not mut but highlights require it because of cursor cache match &mut self.view { Some(view) => { let area = Rect::new(0, 0, self.size.0, self.size.1); let mut stdout = stdout(); self.surface.reset(); // reset is faster than allocating new empty surface // clear with background color self.surface .set_style(area, view.theme.get("ui.background")); let offset = 5 + 1; // 5 linenr + 1 gutter let viewport = Rect::new(offset, 0, self.size.0, self.size.1 - 1); // - 1 for statusline // TODO: inefficient, should feed chunks.iter() to tree_sitter.parse_with(|offset, pos|) let source_code = view.state.doc().to_string(); let last_line = view.last_line(); let range = { // calculate viewport byte ranges let start = view.state.doc().line_to_byte(view.first_line); let end = view.state.doc().line_to_byte(last_line) + view.state.doc().line(last_line).len_bytes(); start..end }; // TODO: range doesn't actually restrict source, just highlight range // TODO: cache highlight results // TODO: only recalculate when state.doc is actually modified let highlights: Vec<_> = match view.state.syntax.as_mut() { Some(syntax) => { syntax .highlight_iter(source_code.as_bytes(), Some(range), None, |_| None) .unwrap() .collect() // TODO: we collect here to avoid double borrow, fix later } None => vec![Ok(HighlightEvent::Source { start: range.start, end: range.end, })], }; let mut spans = Vec::new(); let mut visual_x = 0; let mut line = 0u16; let visible_selections: Vec = view .state .selection() .ranges() .iter() // TODO: limit selection to one in viewport // .filter(|range| !range.is_empty()) // && range.overlaps(&Range::new(start, end + 1)) .copied() .collect(); 'outer: for event in highlights { match event.unwrap() { HighlightEvent::HighlightStart(span) => { spans.push(span); } HighlightEvent::HighlightEnd => { spans.pop(); } HighlightEvent::Source { start, end } => { // TODO: filter out spans out of viewport for now.. let start = view.state.doc().byte_to_char(start); let end = view.state.doc().byte_to_char(end); // <-- index 744, len 743 let text = view.state.doc().slice(start..end); use helix_core::graphemes::{grapheme_width, RopeGraphemes}; let style = match spans.first() { Some(span) => view.theme.get(view.theme.scopes()[span.0].as_str()), None => Style::default().fg(Color::Rgb(164, 160, 232)), // lavender }; // TODO: we could render the text to a surface, then cache that, that // way if only the selection/cursor changes we can copy from cache // and paint the new cursor. let mut char_index = start; // iterate over range char by char for grapheme in RopeGraphemes::new(&text) { // TODO: track current char_index if grapheme == "\n" { visual_x = 0; line += 1; // TODO: with proper iter this shouldn't be necessary if line >= viewport.height { break 'outer; } } else if grapheme == "\t" { visual_x += (TAB_WIDTH as u16); } else { // Cow will prevent allocations if span contained in a single slice // which should really be the majority case let grapheme = Cow::from(grapheme); let width = grapheme_width(&grapheme) as u16; // TODO: this should really happen as an after pass let style = if visible_selections .iter() .any(|range| range.contains(char_index)) { // cedar style.clone().bg(Color::Rgb(128, 47, 0)) } else { style }; let style = if visible_selections .iter() .any(|range| range.head == char_index) { style.clone().bg(Color::Rgb(255, 255, 255)) } else { style }; // TODO: paint cursor heads except primary self.surface.set_string( offset + visual_x, line, grapheme, style, ); visual_x += width; } // if grapheme == "\t" char_index += 1; } } } } let style: Style = view.theme.get("ui.linenr"); for (i, line) in (view.first_line..last_line).enumerate() { self.surface .set_stringn(0, i as u16, format!("{:>5}", line + 1), 5, style); // lavender } // // iterate over selections and render them // for range in state.selection.ranges() { // // get terminal coords for x,y for each range pos // // TODO: this won't work with multiline // let (y1, x1) = coords_at_pos(&text, range.from()); // let (y2, x2) = coords_at_pos(&text, range.to()); // let area = Rect::new( // (x1 + 2) as u16, // y1 as u16, // (x2 - x1 + 1) as u16, // (y2 - y1 + 1) as u16, // ); // self.surface.set_style(area, select); // } // statusline let mode = match view.state.mode() { Mode::Insert => "INS", Mode::Normal => "NOR", Mode::Goto => "GOTO", }; self.surface.set_style( Rect::new(0, self.size.1 - 1, self.size.0, 1), view.theme.get("ui.statusline"), ); // TODO: unfocused one with different color let text_color = Style::default().fg(Color::Rgb(219, 191, 239)); // lilac self.surface .set_string(1, self.size.1 - 1, mode, text_color); if let Some(path) = view.state.path() { self.surface .set_string(6, self.size.1 - 1, path.to_string_lossy(), text_color); } self.terminal .backend_mut() .draw(self.cache.diff(&self.surface).into_iter()); // swap the buffer std::mem::swap(&mut self.surface, &mut self.cache); // set cursor shape match view.state.mode() { Mode::Insert => write!(stdout, "\x1B[6 q"), Mode::Normal => write!(stdout, "\x1B[2 q"), Mode::Goto => write!(stdout, "\x1B[2 q"), }; // render the cursor let pos = view.state.selection().cursor(); let pos = view .screen_coords_at_pos(&view.state.doc().slice(..), pos) .expect("Cursor is out of bounds."); execute!( stdout, cursor::MoveTo(pos.col as u16 + viewport.x, pos.row as u16 + viewport.y,) ); } None => (), } } pub async fn event_loop(&mut self) { let mut reader = EventStream::new(); let keymap = keymap::default(); self.render(); loop { // Handle key events let mut event = reader.next().await; match event { Some(Ok(Event::Resize(width, height))) => { self.size = (width, height); let area = Rect::new(0, 0, width, height); self.surface = Surface::empty(area); self.cache = Surface::empty(area); // TODO: simplistic ensure cursor in view for now if let Some(view) = &mut self.view { view.size = self.size; view.ensure_cursor_in_view() }; self.render(); } Some(Ok(Event::Key(KeyEvent { code: KeyCode::Char('q'), .. }))) => { break; } Some(Ok(Event::Key(event))) => { // TODO: sequences (`gg`) // TODO: handle count other than 1 if let Some(view) = &mut self.view { match view.state.mode() { Mode::Insert => { let keys = vec![event]; if let Some(command) = keymap[&Mode::Insert].get(&keys) { command(view, 1); } else if let KeyEvent { code: KeyCode::Char(c), .. } = event { commands::insert_char(view, c); } view.ensure_cursor_in_view(); self.render(); } Mode::Normal => { let keys = vec![event]; if let Some(command) = keymap[&Mode::Normal].get(&keys) { command(view, 1); // TODO: simplistic ensure cursor in view for now view.ensure_cursor_in_view(); self.render(); } } Mode::Goto => { // TODO: handle modes and sequences (`gg`) let keys = vec![event]; if let Some(command) = keymap[&Mode::Goto].get(&keys) { // TODO: handle count other than 1 command(view, 1); // TODO: simplistic ensure cursor in view for now view.ensure_cursor_in_view(); self.render(); } } } } } Some(Ok(_)) => { // unhandled event } Some(Err(x)) => panic!(x), None => break, } } } pub async fn run(&mut self) -> Result<(), Error> { enable_raw_mode()?; let mut stdout = stdout(); execute!(stdout, terminal::EnterAlternateScreen)?; // Exit the alternate screen and disable raw mode before panicking let hook = std::panic::take_hook(); std::panic::set_hook(Box::new(move |info| { execute!(std::io::stdout(), terminal::LeaveAlternateScreen); disable_raw_mode(); hook(info); })); self.event_loop().await; // reset cursor shape write!(stdout, "\x1B[2 q"); execute!(stdout, terminal::LeaveAlternateScreen)?; disable_raw_mode()?; Ok(()) } } // TODO: language configs: // tabSize, fileExtension etc, mapping to tree sitter parser // themes: // map tree sitter highlights to color values // // TODO: expand highlight thing so we're able to render only viewport range // TODO: async: maybe pre-cache scopes as empty so we render all graphemes initially as regular ////text until calc finishes // TODO: scope matching: biggest union match? [string] & [html, string], [string, html] & [ string, html] // can do this by sorting our theme matches based on array len (longest first) then stopping at the // first rule that matches (rule.all(|scope| scopes.contains(scope)))