stdio.rs

  1use crate::outputs::ExecutionView;
  2use alacritty_terminal::vte::{
  3    ansi::{Attr, Color, NamedColor, Rgb},
  4    Params, ParamsIter, Parser, Perform,
  5};
  6use core::iter;
  7use gpui::{font, prelude::*, AnyElement, StyledText, TextRun};
  8use settings::Settings as _;
  9use theme::ThemeSettings;
 10use ui::{div, prelude::*, IntoElement, ViewContext};
 11
 12/// Implements the most basic of terminal output for use by Jupyter outputs
 13/// whether:
 14///
 15/// * stdout
 16/// * stderr
 17/// * text/plain
 18/// * traceback from an error output
 19///
 20/// Ideally, we would instead use alacritty::vte::Processor to collect the
 21/// output and then render up to u8::MAX lines of text. However, it's likely
 22/// overkill for 95% of outputs.
 23///
 24/// Instead, this implementation handles:
 25///
 26/// * ANSI color codes (background, foreground), including 256 color
 27/// * Carriage returns/line feeds
 28///
 29/// There is no support for cursor movement, clearing the screen, and other text styles
 30pub struct TerminalOutput {
 31    parser: Parser,
 32    handler: TerminalHandler,
 33}
 34
 35impl TerminalOutput {
 36    pub fn new() -> Self {
 37        Self {
 38            parser: Parser::new(),
 39            handler: TerminalHandler::new(),
 40        }
 41    }
 42
 43    pub fn from(text: &str) -> Self {
 44        let mut output = Self::new();
 45        output.append_text(text);
 46        output
 47    }
 48
 49    pub fn append_text(&mut self, text: &str) {
 50        for byte in text.as_bytes() {
 51            self.parser.advance(&mut self.handler, *byte);
 52        }
 53    }
 54
 55    pub fn render(&self, cx: &ViewContext<ExecutionView>) -> AnyElement {
 56        let theme = cx.theme();
 57        let buffer_font = ThemeSettings::get_global(cx).buffer_font.family.clone();
 58        let runs = self
 59            .handler
 60            .text_runs
 61            .iter()
 62            .chain(Some(&self.handler.current_text_run))
 63            .map(|ansi_run| {
 64                let color = terminal_view::terminal_element::convert_color(
 65                    &ansi_run.fg.unwrap_or(Color::Named(NamedColor::Foreground)),
 66                    theme,
 67                );
 68                let background_color = ansi_run
 69                    .bg
 70                    .map(|bg| terminal_view::terminal_element::convert_color(&bg, theme));
 71
 72                TextRun {
 73                    len: ansi_run.len,
 74                    color,
 75                    background_color,
 76                    underline: Default::default(),
 77                    font: font(buffer_font.clone()),
 78                    strikethrough: None,
 79                }
 80            })
 81            .collect::<Vec<TextRun>>();
 82
 83        // Trim the last trailing newline for visual appeal
 84        let trimmed = self
 85            .handler
 86            .buffer
 87            .strip_suffix('\n')
 88            .unwrap_or(&self.handler.buffer);
 89
 90        let text = StyledText::new(trimmed.to_string()).with_runs(runs);
 91        div()
 92            .font_family(buffer_font)
 93            .child(text)
 94            .into_any_element()
 95    }
 96}
 97
 98#[derive(Clone, Default)]
 99struct AnsiTextRun {
100    len: usize,
101    fg: Option<alacritty_terminal::vte::ansi::Color>,
102    bg: Option<alacritty_terminal::vte::ansi::Color>,
103}
104
105struct TerminalHandler {
106    text_runs: Vec<AnsiTextRun>,
107    current_text_run: AnsiTextRun,
108    buffer: String,
109}
110
111impl TerminalHandler {
112    fn new() -> Self {
113        Self {
114            text_runs: Vec::new(),
115            current_text_run: AnsiTextRun::default(),
116            buffer: String::new(),
117        }
118    }
119
120    fn add_text(&mut self, c: char) {
121        self.buffer.push(c);
122        self.current_text_run.len += 1;
123    }
124
125    fn reset(&mut self) {
126        if self.current_text_run.len > 0 {
127            self.text_runs.push(self.current_text_run.clone());
128        }
129
130        self.current_text_run = AnsiTextRun::default();
131    }
132
133    fn terminal_attribute(&mut self, attr: Attr) {
134        // println!("[terminal_attribute] attr={:?}", attr);
135        if Attr::Reset == attr {
136            self.reset();
137            return;
138        }
139
140        if self.current_text_run.len > 0 {
141            self.text_runs.push(self.current_text_run.clone());
142        }
143
144        let mut text_run = AnsiTextRun::default();
145
146        match attr {
147            Attr::Foreground(color) => text_run.fg = Some(color),
148            Attr::Background(color) => text_run.bg = Some(color),
149            _ => {}
150        }
151
152        self.current_text_run = text_run;
153    }
154
155    fn process_carriage_return(&mut self) {
156        // Find last carriage return's position
157        let last_cr = self.buffer.rfind('\r').unwrap_or(0);
158        self.buffer = self.buffer.chars().take(last_cr).collect();
159
160        // First work through our current text run
161        let mut total_len = self.current_text_run.len;
162        if total_len > last_cr {
163            // We are in the current text run
164            self.current_text_run.len = self.current_text_run.len - last_cr;
165        } else {
166            let mut last_cr_run = 0;
167            // Find the last run before the last carriage return
168            for (i, run) in self.text_runs.iter().enumerate() {
169                total_len += run.len;
170                if total_len > last_cr {
171                    last_cr_run = i;
172                    break;
173                }
174            }
175            self.text_runs = self.text_runs[..last_cr_run].to_vec();
176            self.current_text_run = self.text_runs.pop().unwrap_or(AnsiTextRun::default());
177        }
178
179        self.buffer.push('\r');
180        self.current_text_run.len += 1;
181    }
182}
183
184impl Perform for TerminalHandler {
185    fn print(&mut self, c: char) {
186        // println!("[print] c={:?}", c);
187        self.add_text(c);
188    }
189
190    fn execute(&mut self, byte: u8) {
191        match byte {
192            b'\n' => {
193                self.add_text('\n');
194            }
195            b'\r' => {
196                self.process_carriage_return();
197            }
198            _ => {
199                // Format as hex
200                // println!("[execute] byte={:02x}", byte);
201            }
202        }
203    }
204
205    fn hook(&mut self, _params: &Params, _intermediates: &[u8], _ignore: bool, _c: char) {
206        // noop
207        // println!(
208        //     "[hook] params={:?}, intermediates={:?}, c={:?}",
209        //     _params, _intermediates, _c
210        // );
211    }
212
213    fn put(&mut self, _byte: u8) {
214        // noop
215        // println!("[put] byte={:02x}", _byte);
216    }
217
218    fn unhook(&mut self) {
219        // noop
220    }
221
222    fn osc_dispatch(&mut self, _params: &[&[u8]], _bell_terminated: bool) {
223        // noop
224        // println!("[osc_dispatch] params={:?}", _params);
225    }
226
227    fn csi_dispatch(
228        &mut self,
229        params: &alacritty_terminal::vte::Params,
230        intermediates: &[u8],
231        _ignore: bool,
232        action: char,
233    ) {
234        // println!(
235        //     "[csi_dispatch] action={:?}, params={:?}, intermediates={:?}",
236        //     action, params, intermediates
237        // );
238
239        let mut params_iter = params.iter();
240        // Collect colors
241        match (action, intermediates) {
242            ('m', []) => {
243                if params.is_empty() {
244                    self.terminal_attribute(Attr::Reset);
245                } else {
246                    for attr in attrs_from_sgr_parameters(&mut params_iter) {
247                        match attr {
248                            Some(attr) => self.terminal_attribute(attr),
249                            None => return,
250                        }
251                    }
252                }
253            }
254            _ => {}
255        }
256    }
257
258    fn esc_dispatch(&mut self, _intermediates: &[u8], _ignore: bool, _byte: u8) {
259        // noop
260        // println!(
261        //     "[esc_dispatch] intermediates={:?}, byte={:?}",
262        //     _intermediates, _byte
263        // );
264    }
265}
266
267// The following was pulled from vte::ansi
268#[inline]
269fn attrs_from_sgr_parameters(params: &mut ParamsIter<'_>) -> Vec<Option<Attr>> {
270    let mut attrs = Vec::with_capacity(params.size_hint().0);
271
272    while let Some(param) = params.next() {
273        let attr = match param {
274            [0] => Some(Attr::Reset),
275            [1] => Some(Attr::Bold),
276            [2] => Some(Attr::Dim),
277            [3] => Some(Attr::Italic),
278            [4, 0] => Some(Attr::CancelUnderline),
279            [4, 2] => Some(Attr::DoubleUnderline),
280            [4, 3] => Some(Attr::Undercurl),
281            [4, 4] => Some(Attr::DottedUnderline),
282            [4, 5] => Some(Attr::DashedUnderline),
283            [4, ..] => Some(Attr::Underline),
284            [5] => Some(Attr::BlinkSlow),
285            [6] => Some(Attr::BlinkFast),
286            [7] => Some(Attr::Reverse),
287            [8] => Some(Attr::Hidden),
288            [9] => Some(Attr::Strike),
289            [21] => Some(Attr::CancelBold),
290            [22] => Some(Attr::CancelBoldDim),
291            [23] => Some(Attr::CancelItalic),
292            [24] => Some(Attr::CancelUnderline),
293            [25] => Some(Attr::CancelBlink),
294            [27] => Some(Attr::CancelReverse),
295            [28] => Some(Attr::CancelHidden),
296            [29] => Some(Attr::CancelStrike),
297            [30] => Some(Attr::Foreground(Color::Named(NamedColor::Black))),
298            [31] => Some(Attr::Foreground(Color::Named(NamedColor::Red))),
299            [32] => Some(Attr::Foreground(Color::Named(NamedColor::Green))),
300            [33] => Some(Attr::Foreground(Color::Named(NamedColor::Yellow))),
301            [34] => Some(Attr::Foreground(Color::Named(NamedColor::Blue))),
302            [35] => Some(Attr::Foreground(Color::Named(NamedColor::Magenta))),
303            [36] => Some(Attr::Foreground(Color::Named(NamedColor::Cyan))),
304            [37] => Some(Attr::Foreground(Color::Named(NamedColor::White))),
305            [38] => {
306                let mut iter = params.map(|param| param[0]);
307                parse_sgr_color(&mut iter).map(Attr::Foreground)
308            }
309            [38, params @ ..] => handle_colon_rgb(params).map(Attr::Foreground),
310            [39] => Some(Attr::Foreground(Color::Named(NamedColor::Foreground))),
311            [40] => Some(Attr::Background(Color::Named(NamedColor::Black))),
312            [41] => Some(Attr::Background(Color::Named(NamedColor::Red))),
313            [42] => Some(Attr::Background(Color::Named(NamedColor::Green))),
314            [43] => Some(Attr::Background(Color::Named(NamedColor::Yellow))),
315            [44] => Some(Attr::Background(Color::Named(NamedColor::Blue))),
316            [45] => Some(Attr::Background(Color::Named(NamedColor::Magenta))),
317            [46] => Some(Attr::Background(Color::Named(NamedColor::Cyan))),
318            [47] => Some(Attr::Background(Color::Named(NamedColor::White))),
319            [48] => {
320                let mut iter = params.map(|param| param[0]);
321                parse_sgr_color(&mut iter).map(Attr::Background)
322            }
323            [48, params @ ..] => handle_colon_rgb(params).map(Attr::Background),
324            [49] => Some(Attr::Background(Color::Named(NamedColor::Background))),
325            [58] => {
326                let mut iter = params.map(|param| param[0]);
327                parse_sgr_color(&mut iter).map(|color| Attr::UnderlineColor(Some(color)))
328            }
329            [58, params @ ..] => {
330                handle_colon_rgb(params).map(|color| Attr::UnderlineColor(Some(color)))
331            }
332            [59] => Some(Attr::UnderlineColor(None)),
333            [90] => Some(Attr::Foreground(Color::Named(NamedColor::BrightBlack))),
334            [91] => Some(Attr::Foreground(Color::Named(NamedColor::BrightRed))),
335            [92] => Some(Attr::Foreground(Color::Named(NamedColor::BrightGreen))),
336            [93] => Some(Attr::Foreground(Color::Named(NamedColor::BrightYellow))),
337            [94] => Some(Attr::Foreground(Color::Named(NamedColor::BrightBlue))),
338            [95] => Some(Attr::Foreground(Color::Named(NamedColor::BrightMagenta))),
339            [96] => Some(Attr::Foreground(Color::Named(NamedColor::BrightCyan))),
340            [97] => Some(Attr::Foreground(Color::Named(NamedColor::BrightWhite))),
341            [100] => Some(Attr::Background(Color::Named(NamedColor::BrightBlack))),
342            [101] => Some(Attr::Background(Color::Named(NamedColor::BrightRed))),
343            [102] => Some(Attr::Background(Color::Named(NamedColor::BrightGreen))),
344            [103] => Some(Attr::Background(Color::Named(NamedColor::BrightYellow))),
345            [104] => Some(Attr::Background(Color::Named(NamedColor::BrightBlue))),
346            [105] => Some(Attr::Background(Color::Named(NamedColor::BrightMagenta))),
347            [106] => Some(Attr::Background(Color::Named(NamedColor::BrightCyan))),
348            [107] => Some(Attr::Background(Color::Named(NamedColor::BrightWhite))),
349            _ => None,
350        };
351        attrs.push(attr);
352    }
353
354    attrs
355}
356
357/// Handle colon separated rgb color escape sequence.
358#[inline]
359fn handle_colon_rgb(params: &[u16]) -> Option<Color> {
360    let rgb_start = if params.len() > 4 { 2 } else { 1 };
361    let rgb_iter = params[rgb_start..].iter().copied();
362    let mut iter = iter::once(params[0]).chain(rgb_iter);
363
364    parse_sgr_color(&mut iter)
365}
366
367/// Parse a color specifier from list of attributes.
368fn parse_sgr_color(params: &mut dyn Iterator<Item = u16>) -> Option<Color> {
369    match params.next() {
370        Some(2) => Some(Color::Spec(Rgb {
371            r: u8::try_from(params.next()?).ok()?,
372            g: u8::try_from(params.next()?).ok()?,
373            b: u8::try_from(params.next()?).ok()?,
374        })),
375        Some(5) => Some(Color::Indexed(u8::try_from(params.next()?).ok()?)),
376        _ => None,
377    }
378}