feat: integrate client and server sharing workflows

web/src/core-bridge/worker/shareRead.ts

@@ -0,0 +1,122 @@
+import { ChannelSession, IntegrityError } from '@webdrop/core';
+import { getDraftFile, saveResource, type SavedResource } from '../database';
+import type { FileItem, TextItem } from '../types';
+import { makeFileItem } from './presentation';
+import { active, blobs, getSession } from './sessions';
+import { fail, readJson } from './http';
+import { toShareInfo, type ShareWire } from './wire';
+
+import { flushOutbox, downloadDecrypted } from './transfer';
+import { publishShare } from './presentation';
+import { fetchManifest, type ManifestFile } from './shareManifest';
+import { readShareInfo } from './shareState';
+import { errorMessage } from '../errors';
+
+export async function connectShare(id: string): Promise<void> {
+  active.get(id)?.abort();
+  const controller = new AbortController();
+  active.set(id, controller);
+  try {
+    const opened = await getSession(id);
+    let { session } = opened;
+    const { resource } = opened;
+    if (controller.signal.aborted) return;
+    if (resource.kind !== 'share') throw new Error('资源类型不匹配');
+    const raw = await readShareInfo(session, resource);
+    session = (await getSession(id)).session;
+    if (controller.signal.aborted) return;
+    const share = toShareInfo(raw, resource);
+    resource.state = raw.state;
+    resource.expiresAt = raw.expires_at;
+    await saveResource(resource);
+    publishShare(id, { t: 'share', share });
+
+    if (raw.state === 'draft' && resource.mine) {
+      const resumed = await flushOutbox(resource, session);
+      if (resumed) resource.draftItems = resource.draftItems?.map((item) => item.state.kind === 'incomplete' ? { ...item, state: { kind: 'complete' } } : item);
+      await saveResource(resource);
+      if (controller.signal.aborted) return;
+      for (const item of resource.draftItems ?? []) publishShare(id, { t: 'item', item });
+      publishShare(id, { t: 'ready' });
+      return;
+    }
+
+    await loadSealedManifest(resource, session, raw, controller.signal);
+  } catch (error) {
+    if (controller.signal.aborted) return;
+    publishShare(id, error instanceof IntegrityError
+      ? { t: 'integrity', message: '分享清单校验失败,内容已拒绝显示。' }
+      : { t: 'error', message: errorMessage(error) });
+    publishShare(id, { t: 'ready' });
+  } finally {
+    if (active.get(id) === controller) active.delete(id);
+  }
+}
+
+export function stopShare(id: string): void {
+  active.get(id)?.abort();
+  active.delete(id);
+}
+
+async function loadSealedManifest(resource: SavedResource, session: ChannelSession, raw: ShareWire, signal: AbortSignal): Promise<void> {
+  try {
+    const manifest = await fetchManifest(session, resource.id, raw, signal);
+    const byId = new Map(raw.items.map((item) => [item.item_id, item]));
+    for (let index = 0; index < manifest.items.length; index++) {
+      const entry = manifest.items[index];
+      if (!entry) throw new Error('invalid_manifest_item');
+      if (entry.t === 'text' && typeof entry.text === 'string' && Number.isSafeInteger(entry.ts)) {
+        const item: TextItem = { id: `manifest-text-${index}`, kind: 'text', ts: entry.ts, deviceId: '创建者', state: { kind: 'complete' }, text: entry.text };
+        publishShare(resource.id, { t: 'item', item });
+      } else if (entry.t === 'file' && typeof entry.id === 'string' && typeof entry.size === 'number' && Number.isSafeInteger(entry.size)) {
+        const detail = byId.get(entry.id);
+        const item = makeFileItem(entry.id, entry.name ?? '加密文件', entry.mime ?? 'application/octet-stream', entry.size,
+          entry.ts, { kind: 'complete' }, detail?.downloads_left ?? (detail ? null : 0));
+        item.gated = true;
+        publishShare(resource.id, { t: 'item', item });
+      } else throw new Error('invalid_manifest_item');
+    }
+  } catch {
+    publishShare(resource.id, { t: 'integrity', message: '分享清单格式不正确,内容已拒绝显示。' });
+  }
+  publishShare(resource.id, { t: 'ready' });
+}
+
+export async function getShareBlob(id: string, itemId: string): Promise<Blob> {
+  const cached = blobs.get(`${id}:${itemId}`);
+  if (cached) return cached;
+  const { session, resource } = await getSession(id);
+  if (resource.kind !== 'share') throw new Error('资源类型不匹配');
+  if (resource.state === 'draft' && resource.mine) {
+    const draftFile = await getDraftFile(id, itemId);
+    if (draftFile) {
+      blobs.set(`${id}:${itemId}`, draftFile);
+      return draftFile;
+    }
+  }
+  const raw = await readJson<ShareWire>(`/shares/${id}`, session.authHeaders('read'));
+  const manifest = await fetchManifest(session, id, raw);
+  if (itemId.startsWith('manifest-text-')) {
+    const entry = manifest.items[Number(itemId.slice(14))];
+    if (entry?.t !== 'text') throw fail(404, 'not_found');
+    return new Blob([entry.text], { type: 'text/plain' });
+  }
+  const entry = manifest.items.find((candidate): candidate is ManifestFile => candidate.t === 'file' && candidate.id === itemId);
+  if (!entry) throw fail(404, 'not_found');
+  let result: Awaited<ReturnType<typeof downloadDecrypted>>;
+  try { result = await downloadDecrypted(session, resource, itemId, entry.size); }
+  catch (error) {
+    if (error instanceof IntegrityError) publishShare(id, { t: 'integrity', message: '文件校验失败,内容已丢弃。' });
+    throw error;
+  }
+  blobs.set(`${id}:${itemId}`, result.blob);
+  const fileInfo = raw.items.find((value) => value.item_id === itemId);
+  const remaining = fileInfo?.downloads_left === null || fileInfo?.downloads_left === undefined
+    ? null
+    : Math.max(0, fileInfo.downloads_left - 1);
+  const item: FileItem = makeFileItem(itemId, entry.name ?? '加密文件', entry.mime ?? 'application/octet-stream', entry.size, entry.ts,
+    { kind: 'complete' }, remaining);
+  publishShare(id, { t: 'item', item });
+  return result.blob;
+}
+