forked from mars/breed
408 lines
13 KiB
Rust
408 lines
13 KiB
Rust
/*
|
|
* Copyright (c) 2023 Marceline Cramer
|
|
* Copyright (c) 2023 Emma Tebibyte <emma@tebibyte.media>
|
|
* SPDX-License-Identifier: AGPL-3.0-or-later
|
|
*
|
|
* This program is free software: you can redistribute it and/or modify it under
|
|
* the terms of the GNU Affero General Public License as published by the Free
|
|
* Software Foundation, either version 3 of the License, or (at your option) any
|
|
* later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful, but WITHOUT
|
|
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
|
* FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
|
|
* details.
|
|
*
|
|
* You should have received a copy of the GNU Affero General Public License
|
|
* along with this program. If not, see https://www.gnu.org/licenses/.
|
|
*/
|
|
|
|
use std::{
|
|
env::args,
|
|
fs::File,
|
|
io::{stdout, Read, Stdout, Write},
|
|
os::fd::FromRawFd,
|
|
sync::Arc,
|
|
};
|
|
|
|
use crossterm::{
|
|
cursor,
|
|
event::{read, Event, KeyCode, KeyEvent},
|
|
terminal, ExecutableCommand, Result,
|
|
};
|
|
use parking_lot::Mutex;
|
|
use yacexits::{exit, EX_DATAERR, EX_UNAVAILABLE};
|
|
|
|
mod buffer;
|
|
mod theme;
|
|
|
|
use buffer::Buffer;
|
|
use theme::StyleStore;
|
|
|
|
#[derive(Copy, Clone, Debug, Default)]
|
|
pub struct Cursor {
|
|
pub column: usize,
|
|
pub line: usize,
|
|
}
|
|
|
|
#[derive(Clone, Debug, Default)]
|
|
struct NormalState {
|
|
pub error: Option<String>,
|
|
}
|
|
|
|
#[derive(Clone, Debug, Default)]
|
|
struct CommandState {
|
|
pub buf: String,
|
|
pub cursor: usize,
|
|
}
|
|
|
|
#[derive(Copy, Clone, Debug)]
|
|
struct InsertState {
|
|
append: bool,
|
|
}
|
|
|
|
#[derive(Clone, Debug)]
|
|
enum Mode {
|
|
Normal(NormalState),
|
|
Command(CommandState),
|
|
Visual,
|
|
Insert(InsertState),
|
|
}
|
|
|
|
impl Default for Mode {
|
|
fn default() -> Self {
|
|
Mode::Normal(Default::default())
|
|
}
|
|
}
|
|
|
|
impl Mode {
|
|
pub fn cursor_style(&self) -> cursor::SetCursorStyle {
|
|
use cursor::SetCursorStyle as Style;
|
|
match self {
|
|
Mode::Normal(_) => Style::SteadyBlock,
|
|
Mode::Visual => Style::BlinkingBlock,
|
|
Mode::Insert(_) => Style::BlinkingBar,
|
|
Mode::Command(_) => Style::SteadyUnderScore,
|
|
}
|
|
}
|
|
}
|
|
|
|
#[derive(Copy, Clone, Debug)]
|
|
pub enum Direction {
|
|
Left,
|
|
Down,
|
|
Up,
|
|
Right,
|
|
}
|
|
|
|
struct State {
|
|
pub styles: Arc<Mutex<StyleStore>>,
|
|
pub buffer: Buffer,
|
|
pub cursor: Cursor,
|
|
pub scroll: Cursor,
|
|
pub size: (usize, usize),
|
|
pub mode: Mode,
|
|
pub quit: bool,
|
|
}
|
|
|
|
impl State {
|
|
pub fn from_str(text: &str) -> Result<Self> {
|
|
let styles = Arc::new(Mutex::new(StyleStore::default()));
|
|
let buffer = Buffer::from_str(styles.clone(), text);
|
|
let (cols, rows) = terminal::size()?;
|
|
|
|
Ok(Self {
|
|
styles,
|
|
buffer,
|
|
cursor: Cursor::default(),
|
|
scroll: Cursor::default(),
|
|
size: (cols as usize, rows as usize),
|
|
mode: Mode::default(),
|
|
quit: false,
|
|
})
|
|
}
|
|
|
|
pub fn draw(&mut self, out: &mut impl Write) -> Result<()> {
|
|
// begin update
|
|
let (cols, rows) = terminal::size()?;
|
|
out.execute(terminal::BeginSynchronizedUpdate)?;
|
|
out.execute(terminal::Clear(terminal::ClearType::All))?;
|
|
let mut styles = self.styles.lock();
|
|
|
|
// draw status line
|
|
let mut set_cursor_pos = None;
|
|
let mut show_status_bar = false;
|
|
|
|
match &self.mode {
|
|
Mode::Command(CommandState { buf, cursor }) => {
|
|
let col = *cursor as u16 + 1;
|
|
let row = rows - 1;
|
|
out.execute(cursor::MoveTo(0, row))?;
|
|
write!(out, ":{}", buf)?;
|
|
set_cursor_pos = Some((col, row));
|
|
show_status_bar = true;
|
|
}
|
|
Mode::Normal(NormalState { error: Some(error) }) => {
|
|
let error_style = styles.get_scope("error");
|
|
out.execute(cursor::MoveTo(0, rows - 1))?;
|
|
error_style.print_styled(out, error)?;
|
|
show_status_bar = true;
|
|
}
|
|
_ => {}
|
|
}
|
|
|
|
// draw buffer
|
|
let buffer_rows = if show_status_bar { rows - 1 } else { rows };
|
|
let lr_width = self
|
|
.buffer
|
|
.draw(&mut styles, cols, buffer_rows, self.scroll, out)?;
|
|
|
|
// draw cursor
|
|
let cursor_pos = set_cursor_pos.unwrap_or_else(|| {
|
|
// calculate cursor position on buffer
|
|
let cursor = self.buffer.clamped_cursor(self.cursor);
|
|
let col = cursor.column.saturating_sub(self.scroll.column) as u16;
|
|
let row = cursor.line.saturating_sub(self.scroll.line) as u16;
|
|
let col = col + lr_width as u16;
|
|
(col, row)
|
|
});
|
|
|
|
out.execute(cursor::MoveTo(cursor_pos.0, cursor_pos.1))?;
|
|
out.execute(self.mode.cursor_style())?;
|
|
|
|
// finish update
|
|
out.execute(terminal::EndSynchronizedUpdate)?;
|
|
Ok(())
|
|
}
|
|
|
|
pub fn on_event(&mut self, event: Event) {
|
|
match &self.mode {
|
|
Mode::Normal(state) => self.on_normal_event(event, state.clone()),
|
|
Mode::Command(state) => self.on_command_event(event, state.clone()),
|
|
Mode::Visual => self.on_visual_event(event),
|
|
Mode::Insert(state) => self.on_insert_event(event, state.clone()),
|
|
}
|
|
}
|
|
|
|
fn on_normal_event(&mut self, event: Event, mut state: NormalState) {
|
|
// reset the error from the last event
|
|
state.error = None;
|
|
|
|
match event {
|
|
Event::Key(KeyEvent { code, .. }) => match code {
|
|
KeyCode::Char('i') => {
|
|
let state = InsertState { append: false };
|
|
self.mode = Mode::Insert(state);
|
|
}
|
|
KeyCode::Char('a') => {
|
|
let state = InsertState { append: true };
|
|
self.move_cursor(Direction::Right);
|
|
self.mode = Mode::Insert(state);
|
|
}
|
|
KeyCode::Char('o') => {
|
|
let state = InsertState { append: false };
|
|
self.cursor.line += 1;
|
|
self.cursor.column = 0;
|
|
self.buffer.insert_char(self.cursor, '\n');
|
|
self.mode = Mode::Insert(state);
|
|
}
|
|
KeyCode::Char('O') => {
|
|
let state = InsertState { append: false };
|
|
self.cursor.column = 0;
|
|
self.buffer.insert_char(self.cursor, '\n');
|
|
self.mode = Mode::Insert(state);
|
|
}
|
|
KeyCode::Char(':') => {
|
|
self.mode = Mode::Command(Default::default());
|
|
}
|
|
KeyCode::Char('v') => {
|
|
self.mode = Mode::Visual;
|
|
}
|
|
code => self.on_any_key(code),
|
|
},
|
|
event => self.on_any_event(event),
|
|
}
|
|
|
|
match self.mode {
|
|
Mode::Normal(_) => self.mode = Mode::Normal(state),
|
|
_ => {}
|
|
}
|
|
}
|
|
|
|
fn on_command_event(&mut self, event: Event, mut state: CommandState) {
|
|
match event {
|
|
Event::Key(KeyEvent { code, .. }) => match code {
|
|
KeyCode::Char(c) => {
|
|
state.buf.insert(state.cursor, c);
|
|
state.cursor += 1;
|
|
}
|
|
KeyCode::Backspace => {
|
|
if state.cursor > 0 {
|
|
state.cursor -= 1;
|
|
state.buf.remove(state.cursor);
|
|
}
|
|
}
|
|
KeyCode::Delete if state.cursor < state.buf.len() => {
|
|
state.buf.remove(state.cursor);
|
|
}
|
|
KeyCode::Left if state.cursor > 0 => {
|
|
state.cursor -= 1;
|
|
}
|
|
KeyCode::Right if state.cursor < state.buf.len() => {
|
|
state.cursor += 1;
|
|
}
|
|
KeyCode::Enter => {
|
|
// TODO add to command history
|
|
let result = self.execute_command(&state.buf);
|
|
let error = result.err();
|
|
self.mode = Mode::Normal(NormalState { error });
|
|
return;
|
|
}
|
|
code => return self.on_any_key(code),
|
|
},
|
|
event => return self.on_any_event(event),
|
|
}
|
|
|
|
self.mode = Mode::Command(state);
|
|
}
|
|
|
|
fn on_visual_event(&mut self, event: Event) {
|
|
match event {
|
|
Event::Key(KeyEvent { code, .. }) => match code {
|
|
KeyCode::Esc => {
|
|
self.mode = Mode::default();
|
|
}
|
|
code => self.on_any_key(code),
|
|
},
|
|
event => self.on_any_event(event),
|
|
}
|
|
}
|
|
|
|
fn on_insert_event(&mut self, event: Event, state: InsertState) {
|
|
match event {
|
|
Event::Key(KeyEvent { code, .. }) => match code {
|
|
KeyCode::Char(c) => {
|
|
self.buffer.insert_char(self.cursor, c);
|
|
self.move_cursor(Direction::Right)
|
|
}
|
|
KeyCode::Backspace => {
|
|
self.move_cursor(Direction::Left);
|
|
self.buffer.remove(self.cursor);
|
|
}
|
|
KeyCode::Delete => {
|
|
self.buffer.remove(self.cursor);
|
|
}
|
|
KeyCode::Enter => {
|
|
self.buffer.insert_char(self.cursor, '\n');
|
|
self.cursor.line += 1;
|
|
self.cursor.column = 0;
|
|
}
|
|
KeyCode::Esc => {
|
|
if state.append {
|
|
self.move_cursor(Direction::Left);
|
|
}
|
|
|
|
self.mode = Mode::default();
|
|
}
|
|
code => self.on_any_key(code),
|
|
},
|
|
event => self.on_any_event(event),
|
|
}
|
|
}
|
|
|
|
fn on_any_event(&mut self, event: Event) {
|
|
match event {
|
|
Event::Resize(cols, rows) => {
|
|
self.size = (cols as usize, rows as usize);
|
|
}
|
|
Event::Key(KeyEvent { code, .. }) => self.on_any_key(code),
|
|
_ => {}
|
|
}
|
|
}
|
|
|
|
fn on_any_key(&mut self, code: KeyCode) {
|
|
match code {
|
|
KeyCode::Esc => self.mode = Mode::default(),
|
|
KeyCode::Char('h') | KeyCode::Left => self.move_cursor(Direction::Left),
|
|
KeyCode::Char('j') | KeyCode::Down => self.move_cursor(Direction::Down),
|
|
KeyCode::Char('k') | KeyCode::Up => self.move_cursor(Direction::Up),
|
|
KeyCode::Char('l') | KeyCode::Right => self.move_cursor(Direction::Right),
|
|
_ => {}
|
|
}
|
|
}
|
|
|
|
fn execute_command(&mut self, command: &str) -> std::result::Result<(), String> {
|
|
match command {
|
|
"q" => self.quit = true,
|
|
command => return Err(format!("unrecognized command {:?}", command)),
|
|
}
|
|
|
|
Ok(())
|
|
}
|
|
|
|
fn move_cursor(&mut self, direction: Direction) {
|
|
self.buffer.move_cursor(&mut self.cursor, direction, true);
|
|
|
|
if self.cursor.column < self.scroll.column + 3 {
|
|
self.scroll.column = self.cursor.column.saturating_sub(3);
|
|
} else if self.cursor.column + 6 >= self.scroll.column + self.size.0 {
|
|
self.scroll.column = self.cursor.column.saturating_sub(self.size.0 - 6);
|
|
}
|
|
|
|
if self.cursor.line < self.scroll.line {
|
|
self.scroll.line = self.cursor.line;
|
|
} else if self.cursor.line + 3 >= self.scroll.line + self.size.1 {
|
|
self.scroll.line = self.cursor.line + 3 - self.size.1;
|
|
}
|
|
}
|
|
}
|
|
|
|
fn screen_main(stdout: &mut Stdout, mut state: State) -> Result<()> {
|
|
while !state.quit {
|
|
state.draw(stdout)?;
|
|
let event = read()?;
|
|
state.on_event(event);
|
|
}
|
|
|
|
Ok(())
|
|
}
|
|
|
|
fn main() -> Result<()> {
|
|
let argv = args().collect::<Vec<String>>();
|
|
let mut buf = Vec::new();
|
|
|
|
match argv.get(1).map(|s| s.as_str()) {
|
|
Some("-") | None => {
|
|
let stdin = 0; // get stdin as a file descriptor
|
|
if unsafe { libc::isatty(stdin) } == 0 {
|
|
unsafe { File::from_raw_fd(stdin) }
|
|
} else {
|
|
File::open("/dev/null").unwrap()
|
|
}
|
|
}
|
|
Some(path) => std::fs::File::open(path).unwrap_or_else(|_| {
|
|
eprintln!("{}: {}: No such file or directory.", argv[0], argv[1]);
|
|
exit(EX_UNAVAILABLE);
|
|
}),
|
|
}
|
|
.read_to_end(&mut buf)
|
|
.unwrap();
|
|
|
|
let text = String::from_utf8(buf).unwrap_or_else(|_| {
|
|
eprintln!(
|
|
"{}: {}: File contents are not valid UTF-8.",
|
|
argv[0], argv[1]
|
|
);
|
|
exit(EX_DATAERR);
|
|
});
|
|
|
|
let state = State::from_str(&text)?;
|
|
let mut stdout = stdout();
|
|
terminal::enable_raw_mode()?;
|
|
stdout.execute(terminal::EnterAlternateScreen)?;
|
|
let result = screen_main(&mut stdout, state);
|
|
stdout.execute(terminal::LeaveAlternateScreen)?;
|
|
terminal::disable_raw_mode()?;
|
|
result
|
|
}
|