Better external API for EditorGrid, returning Option<&mut GridCell> for external code to modify the cells

src/editor/grid.rs

@@ -3,15 +3,15 @@ use log::trace;
 
 use super::style::Style;
 
-type GridCell = Option<(String, Option<Arc<Style>>)>;
+pub type GridCell = Option<(String, Option<Arc<Style>>)>;
 
 pub struct CharacterGrid {
-    pub characters: Vec<GridCell>,
     pub width: u64,
     pub height: u64,
     pub should_clear: bool,
 
     dirty: Vec<bool>,
+    characters: Vec<GridCell>,
 }
 
 impl CharacterGrid {
@@ -25,22 +25,25 @@ impl CharacterGrid {
         }
     }
 
-    pub fn resize(&mut self, new_size: (u64, u64)) {
+    pub fn resize(&mut self, width: u64, height: u64) {
         trace!("Editor resized");
-        self.width = new_size.0;
-        self.height = new_size.1;
+        self.width = width;
+        self.height = height;
         self.clear();
     }
 
     pub fn clear(&mut self) {
         trace!("Editor cleared");
+        self.characters.clear();
+        self.dirty.clear();
+
         let cell_count = (self.width * self.height) as usize;
-        self.characters = vec![None; cell_count];
-        self.dirty = vec![true; cell_count];
+        self.characters.resize_with(cell_count, || None);
+        self.dirty.resize_with(cell_count, || true);
         self.should_clear = true;
     }
 
-    pub fn cell_index(&self, x: u64, y: u64) -> Option<usize> {
+    fn cell_index(&self, x: u64, y: u64) -> Option<usize> {
         if x >= self.width || y >= self.height {
             None
         } else {
@@ -48,6 +51,14 @@ impl CharacterGrid {
         }
     }
 
+    pub fn get_cell<'a>(&'a self, x: u64, y: u64) -> Option<&'a GridCell> {
+        self.cell_index(x,y).map(|idx| &self.characters[idx])
+    }
+    
+    pub fn get_cell_mut<'a>(&'a mut self, x: u64, y: u64) -> Option<&'a mut GridCell> {
+        self.cell_index(x,y).map(move |idx| &mut self.characters[idx])
+    }
+
     pub fn is_dirty_cell(&self, x: u64, y: u64) -> bool {
         if let Some(idx) = self.cell_index(x, y) {
             self.dirty[idx]
@@ -63,7 +74,8 @@ impl CharacterGrid {
     }
 
     pub fn set_dirty_all(&mut self, value: bool) {
-        self.dirty.resize(self.dirty.len(), value);
+        self.dirty.clear();
+        self.dirty.resize_with((self.width * self.height) as usize, || value);
     }
 
     pub fn rows<'a>(&'a self) -> Vec<&'a [GridCell]> {

src/editor/mod.rs

@@ -80,7 +80,7 @@ impl Editor {
                 trace!("Image flushed");
                 REDRAW_SCHEDULER.queue_next_frame();
             },
-            RedrawEvent::Resize { width, height, .. } => self.grid.resize((width, height)),
+            RedrawEvent::Resize { width, height, .. } => self.grid.resize(width, height),
             RedrawEvent::DefaultColorsSet { colors } => self.default_style = Arc::new(Style::new(colors)),
             RedrawEvent::HighlightAttributesDefine { id, style } => { self.defined_styles.insert(id, Arc::new(style)); },
             RedrawEvent::GridLine { row, column_start, cells, .. } => self.draw_grid_line(row, column_start, cells),
@@ -179,14 +179,16 @@ impl Editor {
         }
 
         if text.is_empty() {
-            let cell_index = self.grid.cell_index(*column_pos, row_index).expect("Should not paint outside of grid");
-            self.grid.characters[cell_index] = Some(("".to_string(), style.clone())); // TODO -- Encapsulate 'characters' better
+            if let Some(cell) = self.grid.get_cell_mut(*column_pos, row_index) {
+                *cell = Some(("".to_string(), style.clone()));
+            }
+
             self.grid.set_dirty_cell(*column_pos, row_index);
             *column_pos = *column_pos + 1;
         } else {
             for (i, character) in text.graphemes(true).enumerate() {
-                if let Some(cell_index) = self.grid.cell_index(i as u64 + *column_pos, row_index) {
-                    self.grid.characters[cell_index] = Some((character.to_string(), style.clone())); // TODO -- Encapsulate 'characters' better
+                if let Some(cell) = self.grid.get_cell_mut(i as u64 + *column_pos, row_index) {
+                    *cell = Some((character.to_string(), style.clone()));
                     self.grid.set_dirty_cell(*column_pos, row_index);
                 }
             }
@@ -228,16 +230,17 @@ impl Editor {
 
                 for x in x_iter {
                     let dest_x = x - cols;
-                    let source_idx = self.grid.cell_index(x as u64, y as u64);
-                    let dest_idx = self.grid.cell_index(dest_x as u64, dest_y as u64);
+                    let cell_data = self.grid.get_cell(x as u64, y as u64).cloned();
 
-                    if let (Some(source_idx), Some(dest_idx)) = (source_idx, dest_idx) {
-                        self.grid.characters[dest_idx] = self.grid.characters[source_idx].clone(); // TODO -- Encapsulate 'characters' better
+                    if let Some(cell_data) =  cell_data.clone() {
+                        if let Some(dest_cell) = self.grid.get_cell_mut(dest_x as u64, dest_y as u64) {
+                            *dest_cell = cell_data.clone();
                             self.grid.set_dirty_cell(dest_x as u64, dest_y as u64);
                         }
                     }
                 }
             }
+        }
         trace!("Region scrolled");
     }
 

src/renderer/cursor_renderer.rs

@@ -201,15 +201,15 @@ impl CursorRenderer {
 
         let (character, font_dimensions): (String, Point) = {
             let editor = EDITOR.lock().unwrap();
-            let character = editor.grid.cell_index(grid_x, grid_y)
-                .and_then(|idx| editor.grid.characters[idx].as_ref())
-                .map(|(character, _)| character.clone())
-                .unwrap_or_else(|| ' '.to_string());
-            
-            let is_double = editor.grid.cell_index(grid_x + 1, grid_y)
-                .and_then(|idx| editor.grid.characters[idx].as_ref())
-                .map(|(character, _)| character.is_empty())
-                .unwrap_or(false);
+            let character = match editor.grid.get_cell(grid_x, grid_y) {
+                Some(Some((character, _))) => character.clone(),
+                _ => ' '.to_string(),
+            };
+            
+            let is_double = match editor.grid.get_cell(grid_x + 1, grid_y) {
+                Some(Some((character, _))) => character.is_empty(),
+                _ => false,
+            };
 
             let font_width = match (is_double, &cursor.shape) {
                 (true, CursorShape::Block) => font_width * 2.0,