@atlaskit/editor-plugin-limited-mode/dist/es2019/pm-plugins/main.js

LimitedMode plugin for @atlaskit/editor-core

import { LIMITED_MODE_DEFAULT_DOC_SIZE_THRESHOLD, LIMITED_MODE_DEFAULT_NODE_COUNT_THRESHOLD } from '@atlaskit/editor-common/limited-mode-document-thresholds';
import { SafePlugin } from '@atlaskit/editor-common/safe-plugin';
import { PluginKey } from '@atlaskit/editor-prosemirror/state';
export const limitedModePluginKey = new PluginKey('limitedModePlugin');
/**
 * Determines whether limited mode should be enabled for a document.
 * If this logic changes, update the duplicate in `editor-common/src/node-anchor/node-anchor-provider.ts` to avoid drift.
 *
 * Limited mode is activated when ANY of the following conditions are met:
 * 1. Document size exceeds `LIMITED_MODE_DEFAULT_DOC_SIZE_THRESHOLD`
 * 2. Node count exceeds `LIMITED_MODE_DEFAULT_NODE_COUNT_THRESHOLD`
 * 3. Document contains a legacy-content macro (LCM)
 *
 * Performance optimisations:
 * - Doc size is checked first (O(1)) - if it exceeds threshold, we skip traversal entirely.
 * - If we find an LCM during traversal, we exit early since limited mode will be enabled.
 */
const shouldEnableLimitedModeForDocument = doc => {
  const nodeCountThreshold = LIMITED_MODE_DEFAULT_NODE_COUNT_THRESHOLD;
  const docSizeThreshold = LIMITED_MODE_DEFAULT_DOC_SIZE_THRESHOLD;

  // Early exit: doc size exceeds threshold - O(1), no traversal needed
  if (doc.nodeSize > docSizeThreshold) {
    return true;
  }

  // Single traversal for node count and LCM detection
  let nodeCount = 0;
  let hasLcm = false;
  doc.descendants(node => {
    var _node$attrs;
    nodeCount += 1;
    if (((_node$attrs = node.attrs) === null || _node$attrs === void 0 ? void 0 : _node$attrs.extensionKey) === 'legacy-content') {
      hasLcm = true;

      // Early exit: LCM found — limited mode will be enabled
      return false;
    }
  });

  // LCM condition takes precedence (if we early exited traversal, this is why)
  if (hasLcm) {
    return true;
  }

  // Check node count threshold
  if (nodeCount > nodeCountThreshold) {
    return true;
  }
  return false;
};
export const createPlugin = () => {
  return new SafePlugin({
    key: limitedModePluginKey,
    view: _view => {
      return {};
    },
    state: {
      init(_config, editorState) {
        return {
          documentSizeBreachesThreshold: shouldEnableLimitedModeForDocument(editorState.doc)
        };
      },
      apply: (tr, currentPluginState, _oldState, _newState) => {
        // Don't check the document size if we're already in limited mode.
        // We ALWAYS want to re-check the document size if we're replacing the document (e.g. live-to-live page navigation).

        if (currentPluginState.documentSizeBreachesThreshold && !tr.getMeta('replaceDocument')) {
          return currentPluginState;
        }
        return {
          documentSizeBreachesThreshold: shouldEnableLimitedModeForDocument(tr.doc)
        };
      }
    }
  });
};