Make editor a widget

src/ui/editor.rs

@@ -1,161 +0,0 @@
-use std::iter;
-use std::ops::Range;
-
-use crossterm::style::ContentStyle;
-use toss::frame::{Frame, Pos};
-use toss::styled::Styled;
-use unicode_segmentation::UnicodeSegmentation;
-
-pub struct Editor {
-    text: String,
-
-    /// Index of the cursor in the text.
-    ///
-    /// Must point to a valid grapheme boundary.
-    idx: usize,
-}
-
-impl Editor {
-    pub fn new() -> Self {
-        Self {
-            text: String::new(),
-            idx: 0,
-        }
-    }
-
-    fn grapheme_boundaries(&self) -> Vec<usize> {
-        self.text
-            .grapheme_indices(true)
-            .map(|(i, _)| i)
-            .chain(iter::once(self.text.len()))
-            .collect()
-    }
-
-    /// Ensure the cursor index lies on a grapheme boundary.
-    ///
-    /// If it doesn't, it is moved to the next grapheme boundary.
-    fn move_cursor_to_grapheme_boundary(&mut self) {
-        for i in self.grapheme_boundaries() {
-            #[allow(clippy::comparison_chain)]
-            if i == self.idx {
-                // We're at a valid grapheme boundary already
-                return;
-            } else if i > self.idx {
-                // There was no valid grapheme boundary at our cursor index, so
-                // we'll take the next one we can get.
-                self.idx = i;
-                return;
-            }
-        }
-
-        // This loop should always return since the index behind the last
-        // grapheme is included in the grapheme boundary iterator.
-        panic!("cursor index out of bounds");
-    }
-
-    /// Insert a character at the current cursor position and move the cursor
-    /// accordingly.
-    pub fn insert_char(&mut self, ch: char) {
-        self.text.insert(self.idx, ch);
-        self.idx += 1;
-        self.move_cursor_to_grapheme_boundary();
-    }
-
-    /// Delete the grapheme before the cursor position.
-    pub fn backspace(&mut self) {
-        let boundaries = self.grapheme_boundaries();
-        for (start, end) in boundaries.iter().zip(boundaries.iter().skip(1)) {
-            if *end == self.idx {
-                self.text.replace_range(start..end, "");
-                self.idx = *start;
-                break;
-            }
-        }
-    }
-
-    /// Delete the grapheme after the cursor position.
-    pub fn delete(&mut self) {
-        let boundaries = self.grapheme_boundaries();
-        for (start, end) in boundaries.iter().zip(boundaries.iter().skip(1)) {
-            if *start == self.idx {
-                self.text.replace_range(start..end, "");
-                break;
-            }
-        }
-    }
-
-    pub fn move_cursor_left(&mut self) {
-        let boundaries = self.grapheme_boundaries();
-        for (start, end) in boundaries.iter().zip(boundaries.iter().skip(1)) {
-            if *end == self.idx {
-                self.idx = *start;
-                break;
-            }
-        }
-    }
-
-    pub fn move_cursor_right(&mut self) {
-        let boundaries = self.grapheme_boundaries();
-        for (start, end) in boundaries.iter().zip(boundaries.iter().skip(1)) {
-            if *start == self.idx {
-                self.idx = *end;
-                break;
-            }
-        }
-    }
-
-    fn wrap(&self, frame: &mut Frame, width: usize) -> Vec<Range<usize>> {
-        let mut rows = vec![];
-        let mut start = 0;
-        let mut col = 0;
-        for (i, g) in self.text.grapheme_indices(true) {
-            let grapheme_width = if g == "\t" {
-                frame.tab_width_at_column(col)
-            } else {
-                frame.grapheme_width(g)
-            } as usize;
-
-            if col + grapheme_width > width {
-                rows.push(start..i);
-                start = i;
-                col = grapheme_width;
-            } else {
-                col += grapheme_width;
-            }
-        }
-        rows.push(start..self.text.len());
-        rows
-    }
-
-    pub fn render_highlighted<F>(&self, frame: &mut Frame, pos: Pos, width: usize, highlight: F)
-    where
-        F: Fn(&str) -> Styled,
-    {
-        let text = highlight(&self.text);
-        let row_ranges = self.wrap(frame, width);
-        let breakpoints = row_ranges
-            .iter()
-            .skip(1)
-            .map(|r| r.start)
-            .collect::<Vec<_>>();
-        let rows = text.split_at_indices(&breakpoints);
-        for (i, row) in rows.into_iter().enumerate() {
-            let pos = pos + Pos::new(0, i as i32);
-            frame.write(pos, row);
-        }
-    }
-
-    pub fn render_with_style(
-        &self,
-        frame: &mut Frame,
-        pos: Pos,
-        width: usize,
-        style: ContentStyle,
-    ) {
-        self.render_highlighted(frame, pos, width, |s| Styled::new((s, style)));
-    }
-
-    pub fn render(&self, frame: &mut Frame, pos: Pos, width: usize) {
-        self.render_highlighted(frame, pos, width, |s| Styled::new(s));
-    }
-}