Function SheetViewer

src/components/file-preview/SheetViewer.tsx:70–304

({ filePath, fileName, className }: SheetViewerProps)

}

export default function SheetViewer({ filePath, fileName, className }: SheetViewerProps) {
  const { t } = useTranslation('chat');
  const [state, setState] = useState<LoadState>({ status: 'idle' });
  const [sheetIndex, setSheetIndex] = useState(0);
  const [page, setPage] = useState(0);
  const scrollerRef = useRef<HTMLDivElement | null>(null);

  useEffect(() => {
    let cancelled = false;
    setState({ status: 'loading' });
    setSheetIndex(0);
    setPage(0);

    void (async () => {
      try {
        const res = await readBinaryFile(filePath, { maxBytes: SHEET_MAX_BYTES });
        if (cancelled) return;
        if (!res.ok || !res.data) {
          if (res.error === 'tooLarge') {
            setState({ status: 'tooLarge', size: res.size });
            return;
          }
          setState({ status: 'error', message: String(res.error ?? 'unknown') });
          return;
        }
        const xlsx = await import('xlsx');
        const wb = xlsx.read(res.data, { type: 'array', cellDates: true });
        const sheets: SheetSnapshot[] = wb.SheetNames.map((name) => {
          const ws = wb.Sheets[name];
          if (!ws) {
            return { name, rows: [], columnLetters: [] };
          }
          const aoa = xlsx.utils.sheet_to_json<Array<unknown>>(ws, {
            header: 1,
            defval: '',
            blankrows: false,
            raw: true,
          });
          let maxCols = 0;
          for (const row of aoa) {
            if (Array.isArray(row) && row.length > maxCols) maxCols = row.length;
          }
          const columnLetters: string[] = [];
          for (let i = 0; i < maxCols; i += 1) columnLetters.push(colLetter(i));
          const rows: string[][] = aoa.map((row) => {
            const out = new Array<string>(maxCols).fill('');
            if (!Array.isArray(row)) return out;
            for (let i = 0; i < maxCols; i += 1) {
              out[i] = formatCellValue(row[i]);
            }
            return out;
          });
          return { name, rows, columnLetters };
        });
        if (cancelled) return;
        setState({ status: 'ready', sheets });
      } catch (err) {
        if (cancelled) return;