import {
  replaceIdMiddleware,
  titleMiddleware,
} from '@blocksuite/affine-shared/adapters';
import { sha } from '@blocksuite/global/utils';
import type { DocSnapshot, Schema, Store, Workspace } from '@blocksuite/store';
import { extMimeMap, getAssetName, Transformer } from '@blocksuite/store';

import { download, Unzip, Zip } from './utils.js';

async function exportDocs(
  collection: Workspace,
  schema: Schema,
  docs: Store[]
) {
  const zip = new Zip();
  const job = new Transformer({
    schema,
    blobCRUD: collection.blobSync,
    docCRUD: {
      create: (id: string) => collection.createDoc(id).getStore({ id }),
      get: (id: string) => collection.getDoc(id)?.getStore({ id }) ?? null,
      delete: (id: string) => collection.removeDoc(id),
    },
    middlewares: [
      replaceIdMiddleware(collection.idGenerator),
      titleMiddleware(collection.meta.docMetas),
    ],
  });

  await Promise.all(
    docs
      .map(job.docToSnapshot)
      .filter((snapshot): snapshot is DocSnapshot => !!snapshot)
      .map(async snapshot => {
        // Use the title and id as the snapshot file name
        const title = snapshot.meta.title || 'untitled';
        const id = snapshot.meta.id;
        const snapshotName = `${title}-${id}.snapshot.json`;
        await zip.file(snapshotName, JSON.stringify(snapshot, null, 2));
      })
  );

  const assets = zip.folder('assets');
  const pathBlobIdMap = job.assetsManager.getPathBlobIdMap();
  const assetsMap = job.assets;

  // Add blobs to assets folder, if failed, log the error and continue
  const results = await Promise.all(
    Array.from(pathBlobIdMap.values()).map(async blobId => {
      try {
        await job.assetsManager.readFromBlob(blobId);
        const ext = getAssetName(assetsMap, blobId).split('.').at(-1);
        const blob = assetsMap.get(blobId);
        if (blob) {
          await assets.file(`${blobId}.${ext}`, blob);
          return { success: true, blobId };
        }
        return { success: false, blobId, error: 'Blob not found' };
      } catch (error) {
        console.error(`Failed to process blob: ${blobId}`, error);
        return { success: false, blobId, error };
      }
    })
  );

  const failures = results.filter(r => !r.success);
  if (failures.length > 0) {
    console.warn(`Failed to process ${failures.length} blobs:`, failures);
  }

  const downloadBlob = await zip.generate();
  // Use the collection id as the zip file name
  return download(downloadBlob, `${collection.id}.bs.zip`);
}

async function importDocs(
  collection: Workspace,
  schema: Schema,
  imported: Blob
) {
  const unzip = new Unzip();
  await unzip.load(imported);

  const assetBlobs: [string, Blob][] = [];
  const snapshotsBlobs: Blob[] = [];

  for (const { path, content: blob } of unzip) {
    if (path.includes('MACOSX') || path.includes('DS_Store')) {
      continue;
    }

    if (path.startsWith('assets/')) {
      assetBlobs.push([path, blob]);
      continue;
    }

    if (path === 'info.json') {
      continue;
    }

    if (path.endsWith('.snapshot.json')) {
      snapshotsBlobs.push(blob);
      continue;
    }
  }

  const job = new Transformer({
    schema,
    blobCRUD: collection.blobSync,
    docCRUD: {
      create: (id: string) => collection.createDoc(id).getStore({ id }),
      get: (id: string) => collection.getDoc(id)?.getStore({ id }) ?? null,
      delete: (id: string) => collection.removeDoc(id),
    },
    middlewares: [
      replaceIdMiddleware(collection.idGenerator),
      titleMiddleware(collection.meta.docMetas),
    ],
  });
  const assetsMap = job.assets;

  assetBlobs.forEach(([name, blob]) => {
    const nameWithExt = name.replace('assets/', '');
    const assetsId = nameWithExt.replace(/\.[^/.]+$/, '');
    const ext = nameWithExt.split('.').at(-1) ?? '';
    const mime = extMimeMap.get(ext) ?? '';
    const file = new File([blob], nameWithExt, {
      type: mime,
    });
    assetsMap.set(assetsId, file);
  });

  return Promise.all(
    snapshotsBlobs.map(async blob => {
      const json = await blob.text();
      const snapshot = JSON.parse(json) as DocSnapshot;
      const tasks: Promise<void>[] = [];

      job.walk(snapshot, block => {
        const sourceId = block.props?.sourceId as string | undefined;

        if (sourceId && sourceId.startsWith('/')) {
          const removeSlashId = sourceId.replace(/^\//, '');

          if (assetsMap.has(removeSlashId)) {
            const blob = assetsMap.get(removeSlashId)!;

            tasks.push(
              blob
                .arrayBuffer()
                .then(buffer => sha(buffer))
                .then(hash => {
                  assetsMap.set(hash, blob);
                  block.props.sourceId = hash;
                })
            );
          }
        }
      });

      await Promise.all(tasks);

      return job.snapshotToDoc(snapshot);
    })
  );
}

export const ZipTransformer = {
  exportDocs,
  importDocs,
};