From 422babff5a09bc36583cb9ed1a963ee8046cc9a3 Mon Sep 17 00:00:00 2001
From: Kyle Loveless <kyle@loveless.dev>
Date: Mon, 11 Nov 2024 22:11:09 -0600
Subject: [PATCH] limit right scrolling and snap to end of line

---
 main.ts | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/main.ts b/main.ts
index 026658a..fff5307 100644
--- a/main.ts
+++ b/main.ts
@@ -266,6 +266,7 @@ function editorRefreshScreen() {
 }
 
 function editorMoveCursor(key: string | number) {
+  let row = (e.cursorY >= e.numRows) ? "" : e.row[e.cursorY];
   switch (key) {
     case EditorKey.ARROW_LEFT:
       if (e.cursorX != 0) {
@@ -273,7 +274,9 @@ function editorMoveCursor(key: string | number) {
       }
       break;
     case EditorKey.ARROW_RIGHT:
-      e.cursorX++;
+      if (row != "" && e.cursorX < row.length) {
+        e.cursorX++;
+      }
       break;
     case EditorKey.ARROW_UP:
       if (e.cursorY != 0) {
@@ -286,6 +289,12 @@ function editorMoveCursor(key: string | number) {
       }
       break;
   }
+
+  row = (e.cursorY >= e.numRows) ? "" : e.row[e.cursorY];
+  const rowLen = row != "" ? row.length : 0;
+  if (e.cursorX > rowLen) {
+    e.cursorX = rowLen;
+  }
 }
 
 function editorProcessKeypress() {