Vendor ratatui temporarily (#835)

* Vendor ratatui temporarily

Once https://github.com/tui-rs-revival/ratatui/pull/114 has been merged,
we can undo this! But otherwise we can't publish to crates.io with a git
dependency.

* make tests pass

* Shush.

* these literally just fail in nix, nowhere else

idk how to work with nix properly, and they're also not our tests

1 files changed, 313 insertions, 0 deletions

diff --git a/src/ratatui/widgets/gauge.rs b/src/ratatui/widgets/gauge.rs
new file mode 100644
index 00000000..6b53b975
--- /dev/null
+++ b/src/ratatui/widgets/gauge.rs
@@ -0,0 +1,313 @@
+use crate::ratatui::{
+    buffer::Buffer,
+    layout::Rect,
+    style::{Color, Style},
+    symbols,
+    text::{Span, Spans},
+    widgets::{Block, Widget},
+};
+
+/// A widget to display a task progress.
+///
+/// # Examples:
+///
+/// ```
+/// # use ratatui::widgets::{Widget, Gauge, Block, Borders};
+/// # use ratatui::style::{Style, Color, Modifier};
+/// Gauge::default()
+///     .block(Block::default().borders(Borders::ALL).title("Progress"))
+///     .gauge_style(Style::default().fg(Color::White).bg(Color::Black).add_modifier(Modifier::ITALIC))
+///     .percent(20);
+/// ```
+#[derive(Debug, Clone)]
+pub struct Gauge<'a> {
+    block: Option<Block<'a>>,
+    ratio: f64,
+    label: Option<Span<'a>>,
+    use_unicode: bool,
+    style: Style,
+    gauge_style: Style,
+}
+
+impl<'a> Default for Gauge<'a> {
+    fn default() -> Gauge<'a> {
+        Gauge {
+            block: None,
+            ratio: 0.0,
+            label: None,
+            use_unicode: false,
+            style: Style::default(),
+            gauge_style: Style::default(),
+        }
+    }
+}
+
+impl<'a> Gauge<'a> {
+    pub fn block(mut self, block: Block<'a>) -> Gauge<'a> {
+        self.block = Some(block);
+        self
+    }
+
+    pub fn percent(mut self, percent: u16) -> Gauge<'a> {
+        assert!(
+            percent <= 100,
+            "Percentage should be between 0 and 100 inclusively."
+        );
+        self.ratio = f64::from(percent) / 100.0;
+        self
+    }
+
+    /// Sets ratio ([0.0, 1.0]) directly.
+    pub fn ratio(mut self, ratio: f64) -> Gauge<'a> {
+        assert!(
+            (0.0..=1.0).contains(&ratio),
+            "Ratio should be between 0 and 1 inclusively."
+        );
+        self.ratio = ratio;
+        self
+    }
+
+    pub fn label<T>(mut self, label: T) -> Gauge<'a>
+    where
+        T: Into<Span<'a>>,
+    {
+        self.label = Some(label.into());
+        self
+    }
+
+    pub fn style(mut self, style: Style) -> Gauge<'a> {
+        self.style = style;
+        self
+    }
+
+    pub fn gauge_style(mut self, style: Style) -> Gauge<'a> {
+        self.gauge_style = style;
+        self
+    }
+
+    pub fn use_unicode(mut self, unicode: bool) -> Gauge<'a> {
+        self.use_unicode = unicode;
+        self
+    }
+}
+
+impl<'a> Widget for Gauge<'a> {
+    fn render(mut self, area: Rect, buf: &mut Buffer) {
+        buf.set_style(area, self.style);
+        let gauge_area = match self.block.take() {
+            Some(b) => {
+                let inner_area = b.inner(area);
+                b.render(area, buf);
+                inner_area
+            }
+            None => area,
+        };
+        buf.set_style(gauge_area, self.gauge_style);
+        if gauge_area.height < 1 {
+            return;
+        }
+
+        // compute label value and its position
+        // label is put at the center of the gauge_area
+        let label = {
+            let pct = f64::round(self.ratio * 100.0);
+            self.label
+                .unwrap_or_else(|| Span::from(format!("{}%", pct)))
+        };
+        let clamped_label_width = gauge_area.width.min(label.width() as u16);
+        let label_col = gauge_area.left() + (gauge_area.width - clamped_label_width) / 2;
+        let label_row = gauge_area.top() + gauge_area.height / 2;
+
+        // the gauge will be filled proportionally to the ratio
+        let filled_width = f64::from(gauge_area.width) * self.ratio;
+        let end = if self.use_unicode {
+            gauge_area.left() + filled_width.floor() as u16
+        } else {
+            gauge_area.left() + filled_width.round() as u16
+        };
+        for y in gauge_area.top()..gauge_area.bottom() {
+            // render the filled area (left to end)
+            for x in gauge_area.left()..end {
+                // spaces are needed to apply the background styling
+                buf.get_mut(x, y)
+                    .set_symbol(" ")
+                    .set_fg(self.gauge_style.bg.unwrap_or(Color::Reset))
+                    .set_bg(self.gauge_style.fg.unwrap_or(Color::Reset));
+            }
+            if self.use_unicode && self.ratio < 1.0 {
+                buf.get_mut(end, y)
+                    .set_symbol(get_unicode_block(filled_width % 1.0));
+            }
+        }
+        // set the span
+        buf.set_span(label_col, label_row, &label, clamped_label_width);
+    }
+}
+
+fn get_unicode_block<'a>(frac: f64) -> &'a str {
+    match (frac * 8.0).round() as u16 {
+        1 => symbols::block::ONE_EIGHTH,
+        2 => symbols::block::ONE_QUARTER,
+        3 => symbols::block::THREE_EIGHTHS,
+        4 => symbols::block::HALF,
+        5 => symbols::block::FIVE_EIGHTHS,
+        6 => symbols::block::THREE_QUARTERS,
+        7 => symbols::block::SEVEN_EIGHTHS,
+        8 => symbols::block::FULL,
+        _ => " ",
+    }
+}
+
+/// A compact widget to display a task progress over a single line.
+///
+/// # Examples:
+///
+/// ```
+/// # use ratatui::widgets::{Widget, LineGauge, Block, Borders};
+/// # use ratatui::style::{Style, Color, Modifier};
+/// # use ratatui::symbols;
+/// LineGauge::default()
+///     .block(Block::default().borders(Borders::ALL).title("Progress"))
+///     .gauge_style(Style::default().fg(Color::White).bg(Color::Black).add_modifier(Modifier::BOLD))
+///     .line_set(symbols::line::THICK)
+///     .ratio(0.4);
+/// ```
+pub struct LineGauge<'a> {
+    block: Option<Block<'a>>,
+    ratio: f64,
+    label: Option<Spans<'a>>,
+    line_set: symbols::line::Set,
+    style: Style,
+    gauge_style: Style,
+}
+
+impl<'a> Default for LineGauge<'a> {
+    fn default() -> Self {
+        Self {
+            block: None,
+            ratio: 0.0,
+            label: None,
+            style: Style::default(),
+            line_set: symbols::line::NORMAL,
+            gauge_style: Style::default(),
+        }
+    }
+}
+
+impl<'a> LineGauge<'a> {
+    pub fn block(mut self, block: Block<'a>) -> Self {
+        self.block = Some(block);
+        self
+    }
+
+    pub fn ratio(mut self, ratio: f64) -> Self {
+        assert!(
+            (0.0..=1.0).contains(&ratio),
+            "Ratio should be between 0 and 1 inclusively."
+        );
+        self.ratio = ratio;
+        self
+    }
+
+    pub fn line_set(mut self, set: symbols::line::Set) -> Self {
+        self.line_set = set;
+        self
+    }
+
+    pub fn label<T>(mut self, label: T) -> Self
+    where
+        T: Into<Spans<'a>>,
+    {
+        self.label = Some(label.into());
+        self
+    }
+
+    pub fn style(mut self, style: Style) -> Self {
+        self.style = style;
+        self
+    }
+
+    pub fn gauge_style(mut self, style: Style) -> Self {
+        self.gauge_style = style;
+        self
+    }
+}
+
+impl<'a> Widget for LineGauge<'a> {
+    fn render(mut self, area: Rect, buf: &mut Buffer) {
+        buf.set_style(area, self.style);
+        let gauge_area = match self.block.take() {
+            Some(b) => {
+                let inner_area = b.inner(area);
+                b.render(area, buf);
+                inner_area
+            }
+            None => area,
+        };
+
+        if gauge_area.height < 1 {
+            return;
+        }
+
+        let ratio = self.ratio;
+        let label = self
+            .label
+            .unwrap_or_else(move || Spans::from(format!("{:.0}%", ratio * 100.0)));
+        let (col, row) = buf.set_spans(
+            gauge_area.left(),
+            gauge_area.top(),
+            &label,
+            gauge_area.width,
+        );
+        let start = col + 1;
+        if start >= gauge_area.right() {
+            return;
+        }
+
+        let end = start
+            + (f64::from(gauge_area.right().saturating_sub(start)) * self.ratio).floor() as u16;
+        for col in start..end {
+            buf.get_mut(col, row)
+                .set_symbol(self.line_set.horizontal)
+                .set_style(Style {
+                    fg: self.gauge_style.fg,
+                    bg: None,
+                    add_modifier: self.gauge_style.add_modifier,
+                    sub_modifier: self.gauge_style.sub_modifier,
+                });
+        }
+        for col in end..gauge_area.right() {
+            buf.get_mut(col, row)
+                .set_symbol(self.line_set.horizontal)
+                .set_style(Style {
+                    fg: self.gauge_style.bg,
+                    bg: None,
+                    add_modifier: self.gauge_style.add_modifier,
+                    sub_modifier: self.gauge_style.sub_modifier,
+                });
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    #[should_panic]
+    fn gauge_invalid_percentage() {
+        Gauge::default().percent(110);
+    }
+
+    #[test]
+    #[should_panic]
+    fn gauge_invalid_ratio_upper_bound() {
+        Gauge::default().ratio(1.1);
+    }
+
+    #[test]
+    #[should_panic]
+    fn gauge_invalid_ratio_lower_bound() {
+        Gauge::default().ratio(-0.5);
+    }
+}