From a9b6d72b24fffa55093201c520075d500712a3ff Mon Sep 17 00:00:00 2001
From: Jesse Luehrs <doy@tozt.net>
Date: Fri, 29 Nov 2019 03:55:02 -0500
Subject: track fullwidth continuation cells explicitly

this makes the logic a bit easier to follow
---
 src/grid.rs | 35 +++++++++++++++++++++++++++--------
 1 file changed, 27 insertions(+), 8 deletions(-)

(limited to 'src/grid.rs')

diff --git a/src/grid.rs b/src/grid.rs
index 9619443..d4a8405 100644
--- a/src/grid.rs
+++ b/src/grid.rs
@@ -149,6 +149,10 @@ impl Grid {
         self.visible_row(pos).and_then(|r| r.get(pos.col))
     }
 
+    pub fn drawing_cell(&self, pos: Pos) -> Option<&crate::cell::Cell> {
+        self.drawing_row(pos).and_then(|r| r.get(pos.col))
+    }
+
     pub fn drawing_cell_mut(
         &mut self,
         pos: Pos,
@@ -156,6 +160,11 @@ impl Grid {
         self.drawing_row_mut(pos).and_then(|r| r.get_mut(pos.col))
     }
 
+    pub fn current_cell(&self) -> &crate::cell::Cell {
+        self.drawing_cell(self.pos)
+            .expect("cursor not pointing to a cell")
+    }
+
     pub fn current_cell_mut(&mut self) -> &mut crate::cell::Cell {
         self.drawing_cell_mut(self.pos)
             .expect("cursor not pointing to a cell")
@@ -414,28 +423,38 @@ impl Grid {
     }
 
     pub fn erase_row_forward(&mut self, attrs: crate::attrs::Attrs) {
+        let size = self.size;
         let pos = self.pos;
         let row = self.current_row_mut();
         row.wrap(false);
-        for cell in row.cells_mut().skip(pos.col as usize) {
-            cell.clear(attrs);
+        for col in pos.col..size.cols {
+            row.erase(col as usize, attrs);
         }
     }
 
     pub fn erase_row_backward(&mut self, attrs: crate::attrs::Attrs) {
+        let size = self.size;
         let pos = self.pos;
         let row = self.current_row_mut();
-        for cell in row.cells_mut().take(pos.col as usize + 1) {
-            cell.clear(attrs);
+        for col in 0..=pos.col.min(size.cols - 1) {
+            row.erase(col as usize, attrs);
         }
     }
 
     pub fn insert_cells(&mut self, count: u16) {
         let size = self.size;
         let pos = self.pos;
+        let wide =
+            pos.col < size.cols && self.current_cell().is_wide_continuation();
         let row = self.current_row_mut();
         for _ in 0..count {
+            if wide {
+                row.get_mut(pos.col).unwrap().set_wide_continuation(false);
+            }
             row.insert(pos.col as usize, crate::cell::Cell::default());
+            if wide {
+                row.get_mut(pos.col).unwrap().set_wide_continuation(true);
+            }
         }
         row.truncate(size.cols as usize);
     }
@@ -451,12 +470,12 @@ impl Grid {
     }
 
     pub fn erase_cells(&mut self, count: u16, attrs: crate::attrs::Attrs) {
+        let size = self.size;
         let pos = self.pos;
         let row = self.current_row_mut();
-        for cell in
-            row.cells_mut().skip(pos.col as usize).take(count as usize)
-        {
-            cell.clear(attrs);
+        row.clear_wide(pos.col);
+        for col in pos.col..((pos.col + count).min(size.cols)) {
+            row.erase(col as usize, attrs);
         }
     }
 
-- 
cgit v1.2.3-54-g00ecf