diff options
Diffstat (limited to 'helix-tui/src/backend/crossterm.rs')
| -rw-r--r-- | helix-tui/src/backend/crossterm.rs | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/helix-tui/src/backend/crossterm.rs b/helix-tui/src/backend/crossterm.rs new file mode 100644 index 00000000..f6703e14 --- /dev/null +++ b/helix-tui/src/backend/crossterm.rs @@ -0,0 +1,221 @@ +use crate::{ + backend::Backend, + buffer::Cell, + layout::Rect, + style::{Color, Modifier}, +}; +use crossterm::{ + cursor::{Hide, MoveTo, Show}, + execute, queue, + style::{ + Attribute as CAttribute, Color as CColor, Print, SetAttribute, SetBackgroundColor, + SetForegroundColor, + }, + terminal::{self, Clear, ClearType}, +}; +use std::io::{self, Write}; + +pub struct CrosstermBackend<W: Write> { + buffer: W, +} + +impl<W> CrosstermBackend<W> +where + W: Write, +{ + pub fn new(buffer: W) -> CrosstermBackend<W> { + CrosstermBackend { buffer } + } +} + +impl<W> Write for CrosstermBackend<W> +where + W: Write, +{ + fn write(&mut self, buf: &[u8]) -> io::Result<usize> { + self.buffer.write(buf) + } + + fn flush(&mut self) -> io::Result<()> { + self.buffer.flush() + } +} + +impl<W> Backend for CrosstermBackend<W> +where + W: Write, +{ + fn draw<'a, I>(&mut self, content: I) -> io::Result<()> + where + I: Iterator<Item = (u16, u16, &'a Cell)>, + { + let mut fg = Color::Reset; + let mut bg = Color::Reset; + let mut modifier = Modifier::empty(); + let mut last_pos: Option<(u16, u16)> = None; + for (x, y, cell) in content { + // Move the cursor if the previous location was not (x - 1, y) + if !matches!(last_pos, Some(p) if x == p.0 + 1 && y == p.1) { + map_error(queue!(self.buffer, MoveTo(x, y)))?; + } + last_pos = Some((x, y)); + if cell.modifier != modifier { + let diff = ModifierDiff { + from: modifier, + to: cell.modifier, + }; + diff.queue(&mut self.buffer)?; + modifier = cell.modifier; + } + if cell.fg != fg { + let color = CColor::from(cell.fg); + map_error(queue!(self.buffer, SetForegroundColor(color)))?; + fg = cell.fg; + } + if cell.bg != bg { + let color = CColor::from(cell.bg); + map_error(queue!(self.buffer, SetBackgroundColor(color)))?; + bg = cell.bg; + } + + map_error(queue!(self.buffer, Print(&cell.symbol)))?; + } + + map_error(queue!( + self.buffer, + SetForegroundColor(CColor::Reset), + SetBackgroundColor(CColor::Reset), + SetAttribute(CAttribute::Reset) + )) + } + + fn hide_cursor(&mut self) -> io::Result<()> { + map_error(execute!(self.buffer, Hide)) + } + + fn show_cursor(&mut self) -> io::Result<()> { + map_error(execute!(self.buffer, Show)) + } + + fn get_cursor(&mut self) -> io::Result<(u16, u16)> { + crossterm::cursor::position() + .map_err(|e| io::Error::new(io::ErrorKind::Other, e.to_string())) + } + + fn set_cursor(&mut self, x: u16, y: u16) -> io::Result<()> { + map_error(execute!(self.buffer, MoveTo(x, y))) + } + + fn clear(&mut self) -> io::Result<()> { + map_error(execute!(self.buffer, Clear(ClearType::All))) + } + + fn size(&self) -> io::Result<Rect> { + let (width, height) = + terminal::size().map_err(|e| io::Error::new(io::ErrorKind::Other, e.to_string()))?; + + Ok(Rect::new(0, 0, width, height)) + } + + fn flush(&mut self) -> io::Result<()> { + self.buffer.flush() + } +} + +fn map_error(error: crossterm::Result<()>) -> io::Result<()> { + error.map_err(|e| io::Error::new(io::ErrorKind::Other, e.to_string())) +} + +impl From<Color> for CColor { + fn from(color: Color) -> Self { + match color { + Color::Reset => CColor::Reset, + Color::Black => CColor::Black, + Color::Red => CColor::DarkRed, + Color::Green => CColor::DarkGreen, + Color::Yellow => CColor::DarkYellow, + Color::Blue => CColor::DarkBlue, + Color::Magenta => CColor::DarkMagenta, + Color::Cyan => CColor::DarkCyan, + Color::Gray => CColor::Grey, + Color::DarkGray => CColor::DarkGrey, + Color::LightRed => CColor::Red, + Color::LightGreen => CColor::Green, + Color::LightBlue => CColor::Blue, + Color::LightYellow => CColor::Yellow, + Color::LightMagenta => CColor::Magenta, + Color::LightCyan => CColor::Cyan, + Color::White => CColor::White, + Color::Indexed(i) => CColor::AnsiValue(i), + Color::Rgb(r, g, b) => CColor::Rgb { r, g, b }, + } + } +} + +#[derive(Debug)] +struct ModifierDiff { + pub from: Modifier, + pub to: Modifier, +} + +impl ModifierDiff { + fn queue<W>(&self, mut w: W) -> io::Result<()> + where + W: io::Write, + { + //use crossterm::Attribute; + let removed = self.from - self.to; + if removed.contains(Modifier::REVERSED) { + map_error(queue!(w, SetAttribute(CAttribute::NoReverse)))?; + } + if removed.contains(Modifier::BOLD) { + map_error(queue!(w, SetAttribute(CAttribute::NormalIntensity)))?; + if self.to.contains(Modifier::DIM) { + map_error(queue!(w, SetAttribute(CAttribute::Dim)))?; + } + } + if removed.contains(Modifier::ITALIC) { + map_error(queue!(w, SetAttribute(CAttribute::NoItalic)))?; + } + if removed.contains(Modifier::UNDERLINED) { + map_error(queue!(w, SetAttribute(CAttribute::NoUnderline)))?; + } + if removed.contains(Modifier::DIM) { + map_error(queue!(w, SetAttribute(CAttribute::NormalIntensity)))?; + } + if removed.contains(Modifier::CROSSED_OUT) { + map_error(queue!(w, SetAttribute(CAttribute::NotCrossedOut)))?; + } + if removed.contains(Modifier::SLOW_BLINK) || removed.contains(Modifier::RAPID_BLINK) { + map_error(queue!(w, SetAttribute(CAttribute::NoBlink)))?; + } + + let added = self.to - self.from; + if added.contains(Modifier::REVERSED) { + map_error(queue!(w, SetAttribute(CAttribute::Reverse)))?; + } + if added.contains(Modifier::BOLD) { + map_error(queue!(w, SetAttribute(CAttribute::Bold)))?; + } + if added.contains(Modifier::ITALIC) { + map_error(queue!(w, SetAttribute(CAttribute::Italic)))?; + } + if added.contains(Modifier::UNDERLINED) { + map_error(queue!(w, SetAttribute(CAttribute::Underlined)))?; + } + if added.contains(Modifier::DIM) { + map_error(queue!(w, SetAttribute(CAttribute::Dim)))?; + } + if added.contains(Modifier::CROSSED_OUT) { + map_error(queue!(w, SetAttribute(CAttribute::CrossedOut)))?; + } + if added.contains(Modifier::SLOW_BLINK) { + map_error(queue!(w, SetAttribute(CAttribute::SlowBlink)))?; + } + if added.contains(Modifier::RAPID_BLINK) { + map_error(queue!(w, SetAttribute(CAttribute::RapidBlink)))?; + } + + Ok(()) + } +} |