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, 573 insertions, 0 deletions

diff --git a/src/ratatui/widgets/block.rs b/src/ratatui/widgets/block.rs
new file mode 100644
index 00000000..20b43614
--- /dev/null
+++ b/src/ratatui/widgets/block.rs
@@ -0,0 +1,573 @@
+use crate::ratatui::{
+    buffer::Buffer,
+    layout::{Alignment, Rect},
+    style::Style,
+    symbols::line,
+    text::{Span, Spans},
+    widgets::{Borders, Widget},
+};
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum BorderType {
+    Plain,
+    Rounded,
+    Double,
+    Thick,
+}
+
+impl BorderType {
+    pub fn line_symbols(border_type: BorderType) -> line::Set {
+        match border_type {
+            BorderType::Plain => line::NORMAL,
+            BorderType::Rounded => line::ROUNDED,
+            BorderType::Double => line::DOUBLE,
+            BorderType::Thick => line::THICK,
+        }
+    }
+}
+
+/// Base widget to be used with all upper level ones. It may be used to display a box border around
+/// the widget and/or add a title.
+///
+/// # Examples
+///
+/// ```
+/// # use ratatui::widgets::{Block, BorderType, Borders};
+/// # use ratatui::style::{Style, Color};
+/// Block::default()
+///     .title("Block")
+///     .borders(Borders::LEFT | Borders::RIGHT)
+///     .border_style(Style::default().fg(Color::White))
+///     .border_type(BorderType::Rounded)
+///     .style(Style::default().bg(Color::Black));
+/// ```
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct Block<'a> {
+    /// Optional title place on the upper left of the block
+    title: Option<Spans<'a>>,
+    /// Title alignment. The default is top left of the block, but one can choose to place
+    /// title in the top middle, or top right of the block
+    title_alignment: Alignment,
+    /// Visible borders
+    borders: Borders,
+    /// Border style
+    border_style: Style,
+    /// Type of the border. The default is plain lines but one can choose to have rounded corners
+    /// or doubled lines instead.
+    border_type: BorderType,
+    /// Widget style
+    style: Style,
+}
+
+impl<'a> Default for Block<'a> {
+    fn default() -> Block<'a> {
+        Block {
+            title: None,
+            title_alignment: Alignment::Left,
+            borders: Borders::NONE,
+            border_style: Default::default(),
+            border_type: BorderType::Plain,
+            style: Default::default(),
+        }
+    }
+}
+
+impl<'a> Block<'a> {
+    pub fn title<T>(mut self, title: T) -> Block<'a>
+    where
+        T: Into<Spans<'a>>,
+    {
+        self.title = Some(title.into());
+        self
+    }
+
+    #[deprecated(
+        since = "0.10.0",
+        note = "You should use styling capabilities of `text::Spans` given as argument of the `title` method to apply styling to the title."
+    )]
+    pub fn title_style(mut self, style: Style) -> Block<'a> {
+        if let Some(t) = self.title {
+            let title = String::from(t);
+            self.title = Some(Spans::from(Span::styled(title, style)));
+        }
+        self
+    }
+
+    pub fn title_alignment(mut self, alignment: Alignment) -> Block<'a> {
+        self.title_alignment = alignment;
+        self
+    }
+
+    pub fn border_style(mut self, style: Style) -> Block<'a> {
+        self.border_style = style;
+        self
+    }
+
+    pub fn style(mut self, style: Style) -> Block<'a> {
+        self.style = style;
+        self
+    }
+
+    pub fn borders(mut self, flag: Borders) -> Block<'a> {
+        self.borders = flag;
+        self
+    }
+
+    pub fn border_type(mut self, border_type: BorderType) -> Block<'a> {
+        self.border_type = border_type;
+        self
+    }
+
+    /// Compute the inner area of a block based on its border visibility rules.
+    pub fn inner(&self, area: Rect) -> Rect {
+        let mut inner = area;
+        if self.borders.intersects(Borders::LEFT) {
+            inner.x = inner.x.saturating_add(1).min(inner.right());
+            inner.width = inner.width.saturating_sub(1);
+        }
+        if self.borders.intersects(Borders::TOP) || self.title.is_some() {
+            inner.y = inner.y.saturating_add(1).min(inner.bottom());
+            inner.height = inner.height.saturating_sub(1);
+        }
+        if self.borders.intersects(Borders::RIGHT) {
+            inner.width = inner.width.saturating_sub(1);
+        }
+        if self.borders.intersects(Borders::BOTTOM) {
+            inner.height = inner.height.saturating_sub(1);
+        }
+        inner
+    }
+}
+
+impl<'a> Widget for Block<'a> {
+    fn render(self, area: Rect, buf: &mut Buffer) {
+        if area.area() == 0 {
+            return;
+        }
+        buf.set_style(area, self.style);
+        let symbols = BorderType::line_symbols(self.border_type);
+
+        // Sides
+        if self.borders.intersects(Borders::LEFT) {
+            for y in area.top()..area.bottom() {
+                buf.get_mut(area.left(), y)
+                    .set_symbol(symbols.vertical)
+                    .set_style(self.border_style);
+            }
+        }
+        if self.borders.intersects(Borders::TOP) {
+            for x in area.left()..area.right() {
+                buf.get_mut(x, area.top())
+                    .set_symbol(symbols.horizontal)
+                    .set_style(self.border_style);
+            }
+        }
+        if self.borders.intersects(Borders::RIGHT) {
+            let x = area.right() - 1;
+            for y in area.top()..area.bottom() {
+                buf.get_mut(x, y)
+                    .set_symbol(symbols.vertical)
+                    .set_style(self.border_style);
+            }
+        }
+        if self.borders.intersects(Borders::BOTTOM) {
+            let y = area.bottom() - 1;
+            for x in area.left()..area.right() {
+                buf.get_mut(x, y)
+                    .set_symbol(symbols.horizontal)
+                    .set_style(self.border_style);
+            }
+        }
+
+        // Corners
+        if self.borders.contains(Borders::RIGHT | Borders::BOTTOM) {
+            buf.get_mut(area.right() - 1, area.bottom() - 1)
+                .set_symbol(symbols.bottom_right)
+                .set_style(self.border_style);
+        }
+        if self.borders.contains(Borders::RIGHT | Borders::TOP) {
+            buf.get_mut(area.right() - 1, area.top())
+                .set_symbol(symbols.top_right)
+                .set_style(self.border_style);
+        }
+        if self.borders.contains(Borders::LEFT | Borders::BOTTOM) {
+            buf.get_mut(area.left(), area.bottom() - 1)
+                .set_symbol(symbols.bottom_left)
+                .set_style(self.border_style);
+        }
+        if self.borders.contains(Borders::LEFT | Borders::TOP) {
+            buf.get_mut(area.left(), area.top())
+                .set_symbol(symbols.top_left)
+                .set_style(self.border_style);
+        }
+
+        // Title
+        if let Some(title) = self.title {
+            let left_border_dx = if self.borders.intersects(Borders::LEFT) {
+                1
+            } else {
+                0
+            };
+
+            let right_border_dx = if self.borders.intersects(Borders::RIGHT) {
+                1
+            } else {
+                0
+            };
+
+            let title_area_width = area
+                .width
+                .saturating_sub(left_border_dx)
+                .saturating_sub(right_border_dx);
+
+            let title_dx = match self.title_alignment {
+                Alignment::Left => left_border_dx,
+                Alignment::Center => area.width.saturating_sub(title.width() as u16) / 2,
+                Alignment::Right => area
+                    .width
+                    .saturating_sub(title.width() as u16)
+                    .saturating_sub(right_border_dx),
+            };
+
+            let title_x = area.left() + title_dx;
+            let title_y = area.top();
+
+            buf.set_spans(title_x, title_y, &title, title_area_width);
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::ratatui::layout::Rect;
+
+    #[test]
+    fn inner_takes_into_account_the_borders() {
+        // No borders
+        assert_eq!(
+            Block::default().inner(Rect::default()),
+            Rect {
+                x: 0,
+                y: 0,
+                width: 0,
+                height: 0
+            },
+            "no borders, width=0, height=0"
+        );
+        assert_eq!(
+            Block::default().inner(Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 1
+            }),
+            Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 1
+            },
+            "no borders, width=1, height=1"
+        );
+
+        // Left border
+        assert_eq!(
+            Block::default().borders(Borders::LEFT).inner(Rect {
+                x: 0,
+                y: 0,
+                width: 0,
+                height: 1
+            }),
+            Rect {
+                x: 0,
+                y: 0,
+                width: 0,
+                height: 1
+            },
+            "left, width=0"
+        );
+        assert_eq!(
+            Block::default().borders(Borders::LEFT).inner(Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 1
+            }),
+            Rect {
+                x: 1,
+                y: 0,
+                width: 0,
+                height: 1
+            },
+            "left, width=1"
+        );
+        assert_eq!(
+            Block::default().borders(Borders::LEFT).inner(Rect {
+                x: 0,
+                y: 0,
+                width: 2,
+                height: 1
+            }),
+            Rect {
+                x: 1,
+                y: 0,
+                width: 1,
+                height: 1
+            },
+            "left, width=2"
+        );
+
+        // Top border
+        assert_eq!(
+            Block::default().borders(Borders::TOP).inner(Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 0
+            }),
+            Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 0
+            },
+            "top, height=0"
+        );
+        assert_eq!(
+            Block::default().borders(Borders::TOP).inner(Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 1
+            }),
+            Rect {
+                x: 0,
+                y: 1,
+                width: 1,
+                height: 0
+            },
+            "top, height=1"
+        );
+        assert_eq!(
+            Block::default().borders(Borders::TOP).inner(Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 2
+            }),
+            Rect {
+                x: 0,
+                y: 1,
+                width: 1,
+                height: 1
+            },
+            "top, height=2"
+        );
+
+        // Right border
+        assert_eq!(
+            Block::default().borders(Borders::RIGHT).inner(Rect {
+                x: 0,
+                y: 0,
+                width: 0,
+                height: 1
+            }),
+            Rect {
+                x: 0,
+                y: 0,
+                width: 0,
+                height: 1
+            },
+            "right, width=0"
+        );
+        assert_eq!(
+            Block::default().borders(Borders::RIGHT).inner(Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 1
+            }),
+            Rect {
+                x: 0,
+                y: 0,
+                width: 0,
+                height: 1
+            },
+            "right, width=1"
+        );
+        assert_eq!(
+            Block::default().borders(Borders::RIGHT).inner(Rect {
+                x: 0,
+                y: 0,
+                width: 2,
+                height: 1
+            }),
+            Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 1
+            },
+            "right, width=2"
+        );
+
+        // Bottom border
+        assert_eq!(
+            Block::default().borders(Borders::BOTTOM).inner(Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 0
+            }),
+            Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 0
+            },
+            "bottom, height=0"
+        );
+        assert_eq!(
+            Block::default().borders(Borders::BOTTOM).inner(Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 1
+            }),
+            Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 0
+            },
+            "bottom, height=1"
+        );
+        assert_eq!(
+            Block::default().borders(Borders::BOTTOM).inner(Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 2
+            }),
+            Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 1
+            },
+            "bottom, height=2"
+        );
+
+        // All borders
+        assert_eq!(
+            Block::default()
+                .borders(Borders::ALL)
+                .inner(Rect::default()),
+            Rect {
+                x: 0,
+                y: 0,
+                width: 0,
+                height: 0
+            },
+            "all borders, width=0, height=0"
+        );
+        assert_eq!(
+            Block::default().borders(Borders::ALL).inner(Rect {
+                x: 0,
+                y: 0,
+                width: 1,
+                height: 1
+            }),
+            Rect {
+                x: 1,
+                y: 1,
+                width: 0,
+                height: 0,
+            },
+            "all borders, width=1, height=1"
+        );
+        assert_eq!(
+            Block::default().borders(Borders::ALL).inner(Rect {
+                x: 0,
+                y: 0,
+                width: 2,
+                height: 2,
+            }),
+            Rect {
+                x: 1,
+                y: 1,
+                width: 0,
+                height: 0,
+            },
+            "all borders, width=2, height=2"
+        );
+        assert_eq!(
+            Block::default().borders(Borders::ALL).inner(Rect {
+                x: 0,
+                y: 0,
+                width: 3,
+                height: 3,
+            }),
+            Rect {
+                x: 1,
+                y: 1,
+                width: 1,
+                height: 1,
+            },
+            "all borders, width=3, height=3"
+        );
+    }
+
+    #[test]
+    fn inner_takes_into_account_the_title() {
+        assert_eq!(
+            Block::default().title("Test").inner(Rect {
+                x: 0,
+                y: 0,
+                width: 0,
+                height: 1,
+            }),
+            Rect {
+                x: 0,
+                y: 1,
+                width: 0,
+                height: 0,
+            },
+        );
+        assert_eq!(
+            Block::default()
+                .title("Test")
+                .title_alignment(Alignment::Center)
+                .inner(Rect {
+                    x: 0,
+                    y: 0,
+                    width: 0,
+                    height: 1,
+                }),
+            Rect {
+                x: 0,
+                y: 1,
+                width: 0,
+                height: 0,
+            },
+        );
+        assert_eq!(
+            Block::default()
+                .title("Test")
+                .title_alignment(Alignment::Right)
+                .inner(Rect {
+                    x: 0,
+                    y: 0,
+                    width: 0,
+                    height: 1,
+                }),
+            Rect {
+                x: 0,
+                y: 1,
+                width: 0,
+                height: 0,
+            },
+        );
+    }
+}