From 8021169131bb74f8ca9a1e99f65aa21019448e80 Mon Sep 17 00:00:00 2001
From: Reinis Mazeiks <rMazeiks@users.noreply.github.com>
Date: Tue, 29 Mar 2022 22:49:25 +0300
Subject: [PATCH] feat: prevent accidental send while in code block (#557)

---
 .../common/messaging/MessageBox.tsx           | 21 ++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/src/components/common/messaging/MessageBox.tsx b/src/components/common/messaging/MessageBox.tsx
index 922b9e3c..386bb184 100644
--- a/src/components/common/messaging/MessageBox.tsx
+++ b/src/components/common/messaging/MessageBox.tsx
@@ -130,6 +130,9 @@ const FileAction = styled.div`
 // For sed replacement
 const RE_SED = new RegExp("^s/([^])*/([^])*$");
 
+// Tests for code block delimiters (``` at start of line)
+const RE_CODE_DELIMITER = new RegExp("^```", "gm");
+
 // ! FIXME: add to app config and load from app config
 export const CAN_UPLOAD_AT_ONCE = 5;
 
@@ -415,6 +418,21 @@ export default observer(({ channel }: Props) => {
         }
     }
 
+    function isInCodeBlock(cursor: number): boolean {
+        const content = state.draft.get(channel._id) || "";
+        const contentBeforeCursor = content.substring(0, cursor);
+
+        let delimiterCount = 0;
+        for (const delimiter of contentBeforeCursor.matchAll(
+            RE_CODE_DELIMITER,
+        )) {
+            delimiterCount++;
+        }
+
+        // Odd number of ``` delimiters before cursor => we are in code block
+        return delimiterCount % 2 === 1;
+    }
+
     // TODO: change to useDebounceCallback
     // eslint-disable-next-line
     const debouncedStopTyping = useCallback(
@@ -543,7 +561,8 @@ export default observer(({ channel }: Props) => {
                             !e.shiftKey &&
                             !e.isComposing &&
                             e.key === "Enter" &&
-                            !isTouchscreenDevice
+                            !isTouchscreenDevice &&
+                            !isInCodeBlock(e.currentTarget.selectionStart)
                         ) {
                             e.preventDefault();
                             return send();