So much better

crates/ratatui/src/editor.rs

@@ -60,6 +60,40 @@ pub struct Editor {
     search: SearchState,
 }
 
+impl Editor {
+    pub fn start_selection(&mut self) {
+        self.text.start_selection();
+    }
+
+    pub fn cancel_selection(&mut self) {
+        self.text.cancel_selection();
+    }
+
+    pub fn is_selecting(&self) -> bool {
+        self.text.is_selecting()
+    }
+
+    pub fn copy(&mut self) {
+        self.text.copy();
+    }
+
+    pub fn cut(&mut self) -> bool {
+        self.text.cut()
+    }
+
+    pub fn paste(&mut self) -> bool {
+        self.text.paste()
+    }
+
+    pub fn select_all(&mut self) {
+        self.text.select_all();
+    }
+
+    pub fn selection_range(&self) -> Option<((usize, usize), (usize, usize))> {
+        self.text.selection_range()
+    }
+}
+
 impl Default for Editor {
     fn default() -> Self {
         Self::new()
@@ -300,6 +334,9 @@ impl Editor {
     pub fn render(&self, frame: &mut Frame, area: Rect, highlighter: Highlighter) {
         let (cursor_row, cursor_col) = self.text.cursor();
         let cursor_style = Style::default().bg(Color::White).fg(Color::Black);
+        let selection_style = Style::default().bg(Color::Rgb(60, 80, 120));
+
+        let selection = self.text.selection_range();
 
         let lines: Vec<Line> = self
             .text
@@ -309,39 +346,30 @@ impl Editor {
             .map(|(row, line)| {
                 let tokens = highlighter(row, line);
                 let mut spans: Vec<Span> = Vec::new();
+                let mut col = 0;
 
-                if row == cursor_row {
-                    let mut col = 0;
-                    for (style, text) in tokens {
-                        let text_len = text.chars().count();
-                        if cursor_col >= col && cursor_col < col + text_len {
-                            let before = text.chars().take(cursor_col - col).collect::<String>();
-                            let cursor_char =
-                                text.chars().nth(cursor_col - col).unwrap_or(' ');
-                            let after =
-                                text.chars().skip(cursor_col - col + 1).collect::<String>();
+                for (base_style, text) in tokens {
+                    for ch in text.chars() {
+                        let is_cursor = row == cursor_row && col == cursor_col;
+                        let is_selected = is_in_selection(row, col, selection);
 
-                            if !before.is_empty() {
-                                spans.push(Span::styled(before, style));
-                            }
-                            spans.push(Span::styled(cursor_char.to_string(), cursor_style));
-                            if !after.is_empty() {
-                                spans.push(Span::styled(after, style));
-                            }
+                        let style = if is_cursor {
+                            cursor_style
+                        } else if is_selected {
+                            base_style.bg(selection_style.bg.unwrap())
                         } else {
-                            spans.push(Span::styled(text, style));
-                        }
-                        col += text_len;
-                    }
-                    if cursor_col >= col {
-                        spans.push(Span::styled(" ", cursor_style));
-                    }
-                } else {
-                    for (style, text) in tokens {
-                        spans.push(Span::styled(text, style));
+                            base_style
+                        };
+
+                        spans.push(Span::styled(ch.to_string(), style));
+                        col += 1;
                     }
                 }
 
+                if row == cursor_row && cursor_col >= col {
+                    spans.push(Span::styled(" ", cursor_style));
+                }
+
                 Line::from(spans)
             })
             .collect();
@@ -468,3 +496,23 @@ impl Editor {
 fn is_word_char(c: char) -> bool {
     c.is_alphanumeric() || matches!(c, '!' | '@' | '?' | '.' | ':' | '_' | '#')
 }
+
+fn is_in_selection(row: usize, col: usize, selection: Option<((usize, usize), (usize, usize))>) -> bool {
+    let Some(((start_row, start_col), (end_row, end_col))) = selection else {
+        return false;
+    };
+
+    if row < start_row || row > end_row {
+        return false;
+    }
+
+    if row == start_row && row == end_row {
+        col >= start_col && col < end_col
+    } else if row == start_row {
+        col >= start_col
+    } else if row == end_row {
+        col < end_col
+    } else {
+        true
+    }
+}