upstream-affine/blocksuite/affine/widgets/drag-handle/src/middleware/new-id-cross-doc.ts

import { DatabaseBlockModel } from '@blocksuite/affine-model';
import { matchModels } from '@blocksuite/affine-shared/utils';
import type { BlockStdScope } from '@blocksuite/std';
import type { TransformerMiddleware } from '@blocksuite/store';

export const newIdCrossDoc =
  (std: BlockStdScope): TransformerMiddleware =>
  ({ slots }) => {
    let samePage = false;
    const oldToNewIdMap = new Map<string, string>();

    const beforeImportSliceSubscription = slots.beforeImport.subscribe(
      payload => {
        if (payload.type === 'slice') {
          samePage = payload.snapshot.pageId === std.store.id;
        }
        if (payload.type === 'block' && !samePage) {
          const newId = std.workspace.idGenerator();

          oldToNewIdMap.set(payload.snapshot.id, newId);
          payload.snapshot.id = newId;
        }
      }
    );

    const afterImportBlockSubscription = slots.afterImport.subscribe(
      payload => {
        if (
          !samePage &&
          payload.type === 'block' &&
          matchModels(payload.model, [DatabaseBlockModel])
        ) {
          const originalCells = payload.model.props.cells;
          const newCells = {
            ...originalCells,
          };

          Object.keys(originalCells).forEach(cellId => {
            if (oldToNewIdMap.has(cellId)) {
              newCells[oldToNewIdMap.get(cellId)!] = originalCells[cellId];
            }
          });

          payload.model.props.cells$.value = newCells;
        }
      }
    );

    return () => {
      beforeImportSliceSubscription.unsubscribe();
      afterImportBlockSubscription.unsubscribe();
    };
  };