Function routeTableKey

packages/core/src/runtime/router/table.ts:30–232

(event: ZrevEvent, ctx: TableRoutingCtx<T>)

 *   - Ctrl+A: Select all (multi mode)
 */
export function routeTableKey<T>(event: ZrevEvent, ctx: TableRoutingCtx<T>): TableRoutingResult {
  if (event.kind !== "key") return Object.freeze({ consumed: false });
  if (event.action !== "down") return Object.freeze({ consumed: false });
  if (!ctx.keyboardNavigation) return Object.freeze({ consumed: false });

  const { tableId, rowKeys, rowKeyToIndex, rowHeight, state, selection, selectionMode } = ctx;
  const { focusedRowIndex, scrollTop, viewportHeight, lastClickedKey } = state;
  const rowCount = rowKeys.length;

  if (rowCount === 0) return Object.freeze({ consumed: false });
  const clampedFocusedRowIndex = Math.max(0, Math.min(rowCount - 1, focusedRowIndex));

  // Keep keyboard routing consistent with renderer math.
  const safeRowHeight = rowHeight > 0 ? rowHeight : 1;
  const safeViewportHeight = Math.max(0, viewportHeight);
  const maxScrollTop = Math.max(0, rowCount * safeRowHeight - safeViewportHeight);
  const normalizedScrollTop = Number.isFinite(scrollTop)
    ? Math.max(0, Math.min(maxScrollTop, scrollTop))
    : 0;
  const consumedNoMove = (): TableRoutingResult => {
    const scrollPatch =
      normalizedScrollTop !== scrollTop ? { nextScrollTop: normalizedScrollTop } : {};
    const focusPatch =
      clampedFocusedRowIndex !== focusedRowIndex
        ? { nextFocusedRowIndex: clampedFocusedRowIndex }
        : {};
    return Object.freeze({
      consumed: true,
      ...scrollPatch,
      ...focusPatch,
    });
  };

  // Helper to compute scroll position for a given row index
  const scrollToRow = (rowIndex: number): number => {
    const rowTop = rowIndex * safeRowHeight;
    const rowBottom = rowTop + safeRowHeight;
    const viewportBottom = normalizedScrollTop + safeViewportHeight;

    // If row is above viewport, scroll up
    if (rowTop < normalizedScrollTop) {
      return rowTop;
    }
    // If row is below viewport, scroll down
    if (rowBottom > viewportBottom) {
      return Math.max(0, Math.min(maxScrollTop, rowBottom - safeViewportHeight));
    }
    // Row is visible
    return normalizedScrollTop;
  };

  // Compute page size
  const pageSize = Math.max(1, Math.floor(safeViewportHeight / safeRowHeight));

  // Arrow Up
  if (event.key === ZR_KEY_UP) {
    const nextIndex = Math.max(0, clampedFocusedRowIndex - 1);
    if (nextIndex === clampedFocusedRowIndex) return consumedNoMove();