Simplify handleTextareaScroll and remove unused memoized functions in App.tsx

2026-02-01 03:48:42 +01:00
parent 574e7899a5
commit 10c6043e4e
1 changed files with 1 additions and 100 deletions
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -319,106 +319,7 @@ export default function App() {
  const sidebarExpandIconSrc =
    theme === "light" ? sidebarExpandIconBright : sidebarExpandIcon;
-  const lines = useMemo(() => body.split("\n"), [body]);
+  const handleTextareaScroll = useCallback(() => {}, []);
  const lineCount = lines.length;
  const getLineTop = useCallback(
    (index: number) => {
      const tops = lineTopsRef.current;
      return tops[index] ?? 0;
    },
    [lineNumbersVersion]
  );
  const getTotalHeight = useCallback(() => {
    const tops = lineTopsRef.current;
    return tops[lineCount] ?? 0;
  }, [lineCount, lineNumbersVersion]);
  const findLineAtOffset = useCallback(
    (offset: number) => {
      if (lineCount === 0) return 0;
      const tops = lineTopsRef.current;
      if (tops.length === 0) return 0;
      let low = 0;
      let high = lineCount;
      while (low < high) {
        const mid = Math.floor((low + high) / 2);
        if ((tops[mid + 1] ?? 0) <= offset) {
          low = mid + 1;
        } else {
          high = mid;
        }
      }
      return Math.min(Math.max(0, low), Math.max(0, lineCount - 1));
    },
    [lineCount]
  );
  const updateVisibleRange = useCallback(() => {
    if (!showLineNumbersActive) return;
    const textarea = textareaRef.current;
    if (!textarea) return;
    const scrollTop = textarea.scrollTop;
    const viewportHeight = textarea.clientHeight;
    if (lineTopsRef.current.length === 0) return;
    const start = findLineAtOffset(scrollTop);
    const end = findLineAtOffset(scrollTop + viewportHeight);
    const buffer = 8;
    const nextStart = Math.max(0, start - buffer);
    const nextEnd = Math.min(lineCount - 1, end + buffer);
    setVisibleRange((prev) =>
      prev.start === nextStart && prev.end === nextEnd
        ? prev
        : { start: nextStart, end: nextEnd }
    );
  }, [defaultLineHeight, findLineAtOffset, lineCount, showLineNumbersActive]);
  const totalLineNumberHeight = useMemo(
    () => (showLineNumbersActive ? getTotalHeight() : 0),
    [getTotalHeight, showLineNumbersActive]
  );
  const visibleLineNumbers = useMemo(() => {
    if (!showLineNumbersActive || visibleRange.end < visibleRange.start) return [];
    const items: { line: number; top: number; height: number }[] = [];
    for (let i = visibleRange.start; i <= visibleRange.end; i += 1) {
      const height = lineHeightsRef.current[i] || defaultLineHeight || 0;
      items.push({
        line: i + 1,
        top: getLineTop(i),
        height
      });
    }
    return items;
  }, [
    defaultLineHeight,
    getLineTop,
    lineNumbersVersion,
    showLineNumbersActive,
    visibleRange.end,
    visibleRange.start
  ]);
  const scheduleUpdateVisibleRange = useCallback(() => {
    if (scrollRafRef.current) {
      cancelAnimationFrame(scrollRafRef.current);
    }
    scrollRafRef.current = requestAnimationFrame(() => {
      updateVisibleRange();
    });
  }, [updateVisibleRange]);
  const handleTextareaScroll = useCallback(
    (event: React.UIEvent<HTMLTextAreaElement>) => {
      if (!showLineNumbersActive) return;
      if (lineNumbersRef.current) {
        lineNumbersRef.current.scrollTop = event.currentTarget.scrollTop;
      }
      scheduleUpdateVisibleRange();
    },
    [scheduleUpdateVisibleRange, showLineNumbersActive]
  );
  useEffect(() => {
    if (!showLineNumbersActive) return;