@atlaskit/editor-plugin-show-diff/dist/es2019/pm-plugins/scrollToDiff.js

ShowDiff plugin for @atlaskit/editor-core

import { tableMarginTop } from '@atlaskit/editor-common/styles';
import { getStickyHeaderHeight } from '@atlaskit/editor-common/table/get-sticky-header-height';
import { fg } from '@atlaskit/platform-feature-flags/fg';
import { isDiffDecoration, SCROLL_TARGET_MARGIN_CSS_PROPERTY } from './decorations/decorationKeys';

/**
 * Extra space above the scrolled-to element so it does not sit flush under the
 * viewport edge (helps with sticky table headers, toolbars, etc.).
 *
 * Implemented with `scroll-margin-top` so we still use the browser’s native
 * `scrollIntoView`, which scrolls every relevant scrollport (nested containers
 * and the window). A single manual `scrollTop` on one ancestor often misses
 * outer scroll or mis-identifies the active scroll container.
 */
const SCROLL_TOP_MARGIN_PX = 100;
function updateScrollTargetMargin(view, targetPos, api) {
  var _api$limitedMode, _api$limitedMode$shar;
  const isLimitedModeEnabled = Boolean(api === null || api === void 0 ? void 0 : (_api$limitedMode = api.limitedMode) === null || _api$limitedMode === void 0 ? void 0 : (_api$limitedMode$shar = _api$limitedMode.sharedState.currentState()) === null || _api$limitedMode$shar === void 0 ? void 0 : _api$limitedMode$shar.enabled);
  const tableHeaderHeight = isLimitedModeEnabled ? undefined : getStickyHeaderHeight(view, targetPos);
  view.dom.style.setProperty(SCROLL_TARGET_MARGIN_CSS_PROPERTY, `${tableHeaderHeight ? tableHeaderHeight + tableMarginTop : 0}px`);
}

/**
 * Returns the resolved HTMLElement for a given DOM node, walking up to the
 * parent element if the node itself is not an Element (e.g. a text node).
 */
function scrollToSelection(node) {
  const element = node instanceof Element ? node : (node === null || node === void 0 ? void 0 : node.parentElement) instanceof Element ? node.parentElement : null;
  if (!(element instanceof HTMLElement)) {
    return;
  }
  if (fg('platform_editor_ai_show_diff_patch_1')) {
    element.scrollIntoView({
      behavior: 'smooth',
      block: 'start'
    });
    return;
  }

  // scroll-margin is included in scroll-into-view math; it does not change layout.
  const previousScrollMarginTop = element.style.scrollMarginTop;
  element.style.scrollMarginTop = `${SCROLL_TOP_MARGIN_PX}px`;
  try {
    element.scrollIntoView({
      behavior: 'smooth',
      block: 'start'
    });
  } finally {
    element.style.scrollMarginTop = previousScrollMarginTop;
  }
}

/**
 * Schedules scrolling to the decoration at the given index after the next frame. Defaults to the
 * first decoration when no index is provided.
 *
 * @returns A function that cancels the scheduled `requestAnimationFrame` if it has not run yet.
 */
export const scrollToDecoration = (view, decorations, activeIndex = 0, api) => {
  const decoration = decorations[activeIndex];
  if (!decoration) {
    return () => {};
  }

  // A grouped decoration spans a whole customer-facing edit, which can visually start with a
  // deleted-content widget rather than at the group's `from` position — see `scrollTarget` in
  // `getScrollableDecorations`. Only set under `platform_editor_ai_show_diff_patch_1`.
  const target = isDiffDecoration(decoration) && decoration.spec.scrollTarget || decoration;
  let rafId = requestAnimationFrame(() => {
    rafId = null;
    if (fg('platform_editor_ai_show_diff_patch_1')) {
      updateScrollTargetMargin(view, target.from, api);
    }
    if (isDiffDecoration(target) && target.spec.decorationType === 'widget') {
      var _target$type;
      // @ts-expect-error - decoration.type is not typed public API
      const widgetDom = target === null || target === void 0 ? void 0 : (_target$type = target.type) === null || _target$type === void 0 ? void 0 : _target$type.toDOM;
      scrollToSelection(widgetDom);
    } else if (isDiffDecoration(target) && fg('platform_editor_ai_show_diff_patch_2')) {
      var _Array$from$find;
      const targetNode = (_Array$from$find = Array.from(view.dom.querySelectorAll('[data-diff-id]')).find(element => element.dataset.diffId === target.spec.diffId)) !== null && _Array$from$find !== void 0 ? _Array$from$find : view.nodeDOM(target === null || target === void 0 ? void 0 : target.from);
      scrollToSelection(targetNode);
    } else {
      var _view$domAtPos;
      const targetNode = view.nodeDOM(target === null || target === void 0 ? void 0 : target.from);
      const node = targetNode instanceof Element ? targetNode : (_view$domAtPos = view.domAtPos(target === null || target === void 0 ? void 0 : target.from)) === null || _view$domAtPos === void 0 ? void 0 : _view$domAtPos.node;
      scrollToSelection(node);
    }
  });
  return () => {
    if (rafId !== null) {
      cancelAnimationFrame(rafId);
      rafId = null;
    }
  };
};