feat: sync unfiled drafts across devices (Closes #851)

frontend/dashboard.js

@@ -304,6 +304,7 @@
     if (!response.ok) {
       const error = new Error(payload.error || payload.detail?.message || payload.detail || 'Review request failed.');
       error.status = response.status;
+
       error.code = payload.detail?.code;
       const retryAfter = response.headers.get('Retry-After');
       error.retryAfter = retryAfter === null ? undefined : Number(retryAfter);
@@ -530,6 +531,9 @@
     getCaptureLogin: () => String(lastContextSnapshot?.user?.login || '').trim(),
     getCurrentLogin: () => activeFlushLogin,
   });
+  createUnfiledDraftSync(
+    unfiledCaptures, fetchReviewJson
+  );
   const dFS = createDraftFilingSession({list:()=>unfiledCaptures.list().filter(item=>!item.quarantined)});
   dFS.attach(qs, {
     captures:unfiledCaptures, issueCapture, attachment:createIssueAttachmentController,
@@ -2782,7 +2786,9 @@
       button.addEventListener('click', async () => {
         if (!window.confirm('Discard this unfinished draft?')) return;
         const item = lastDrafts[Number(button.dataset.draftIndex)];
-        if (item?.kind === 'unfiled-issue') await unfiledCaptures.discard(item.capture_id);
+        if (item?.kind === 'unfiled-issue') {
+          await unfiledCaptures.discard(item.capture_id);
+        }
         else if (item?.kind === 'issue-outbox') issueOutbox.discard(item.outbox_id);
         else if (item?.kind === 'authored-outbox') authoredOutbox.discard(item.outbox_id);
         else if (item) draftInbox.discard(item.id);

frontend/index.html

@@ -1222,6 +1222,7 @@
 <script src="static/widgets.js"></script>
 <script src="static/drafts.js"></script>
 <script src="static/unfiled-captures.js"></script>
+<script src="static/unfiled-draft-sync.js"></script>
 <script src="static/shared-image-capture.js"></script>
 <script src="static/draft-filing-session.js"></script>
 <script src="static/draft-capacity-dialog.js"></script>

frontend/service-worker.js

@@ -24,6 +24,7 @@ const SHELL = [
   BASE + 'static/widgets.js',
   BASE + 'static/drafts.js',
   BASE + 'static/unfiled-captures.js',
+  BASE + 'static/unfiled-draft-sync.js',
   BASE + 'static/shared-image-capture.js',
   BASE + 'static/draft-filing-session.js',
   BASE + 'static/draft-capacity-dialog.js',

frontend/unfiled-captures.js

@@ -8,6 +8,8 @@ function createUnfiledCaptures({
   maxItems = 20,
 }) {
   const storageKey = 'stackchain.unfiled-issues.v1';
+  const listeners = new Set();
+  const onChange = (id, removed) => listeners.forEach(listener => listener(id, removed));
 
   function read() {
     try {
@@ -94,6 +96,7 @@ function createUnfiledCaptures({
         if (prepared.hasAttachment) Promise.resolve(attachmentStore.delete(item.id)).catch(() => {});
         throw error;
       }
+      onChange(item.id, false);
       return item;
     };
     const stage = prepared.hasAttachment
@@ -150,6 +153,7 @@ function createUnfiledCaptures({
     const removed = items.find(item => item.id === id);
     if (!removed?.hasAttachment) {
       write(remaining);
+      onChange(id, true);
       return true;
     }
     return Promise.resolve(attachmentStore?.get(id)).then(removedAttachment =>
@@ -159,6 +163,7 @@ function createUnfiledCaptures({
           if (removedAttachment) await Promise.resolve(attachmentStore?.put(id, removedAttachment)).catch(() => {});
           throw error;
         }
+        onChange(id, true);
         return true;
       })
     );
@@ -191,7 +196,86 @@ function createUnfiledCaptures({
 
   function completeResume(id) { return discard(id); }
 
-  return {list, capacity, save, replaceOldest, discard, resume, completeResume};
+  function encodeBytes(buffer) {
+    const bytes = new Uint8Array(buffer);
+    let binary = '';
+    for (let offset = 0; offset < bytes.length; offset += 0x8000) {
+      binary += String.fromCharCode(...bytes.subarray(offset, offset + 0x8000));
+    }
+    return btoa(binary);
+  }
+
+  function decodeBytes(value, contentType) {
+    const binary = atob(value);
+    const bytes = new Uint8Array(binary.length);
+    for (let index = 0; index < binary.length; index += 1) bytes[index] = binary.charCodeAt(index);
+    return new Blob([bytes], {type:contentType});
+  }
+
+  async function exportOwned(login) {
+    const owner = String(login || '').trim();
+    const exported = [];
+    for (const item of read().filter(candidate => candidate.ownerLogin === owner)) {
+      let evidence = [];
+      if (item.hasAttachment) {
+        const stored = await attachmentStore?.get(item.id);
+        const attachments = Array.isArray(stored?.attachments) ? stored.attachments :
+          (stored?.blob ? [stored] : []);
+        if (attachments.length !== Number(item.attachmentCount || 1)) {
+          throw new Error('The saved screenshots are unavailable. Keep this Draft and retry.');
+        }
+        evidence = await Promise.all(attachments.map(async attachment => ({
+          filename:attachment.filename,
+          content_type:attachment.contentType,
+          ...(attachment.note ? {note:attachment.note} : {}),
+          data:encodeBytes(await attachment.blob.arrayBuffer()),
+        })));
+      }
+      exported.push({
+        id:item.id, title:item.title, body:item.body, saved_at:Number(item.savedAt),
+        ...(Array.isArray(item.blockers) && item.blockers.length ? {blockers:item.blockers} : {}),
+        ...(evidence.length ? {evidence} : {}),
+      });
+    }
+    return exported;
+  }
+
+  async function mergeRemote(drafts, login) {
+    const ownerLogin = String(login || '').trim();
+    if (!ownerLogin || !Array.isArray(drafts)) return 0;
+    const existing = read();
+    const known = new Set(existing.map(item => item.id));
+    const imported = [];
+    for (const remote of drafts) {
+      if (!remote || known.has(remote.id) || imported.length + existing.length >= maxItems) continue;
+      const evidence = Array.isArray(remote.evidence) ? remote.evidence : [];
+      if (evidence.length && !attachmentStore) continue;
+      const item = {
+        id:String(remote.id), ownerLogin, title:String(remote.title || ''), body:String(remote.body || ''),
+        savedAt:Number(remote.saved_at),
+        ...(Array.isArray(remote.blockers) && remote.blockers.length ? {
+          blockers:remote.blockers, blockerCount:remote.blockers.length,
+        } : {}),
+        ...(evidence.length ? {hasAttachment:true, attachmentCount:evidence.length} : {}),
+      };
+      if (!item.id || !item.title.trim() || !Number.isFinite(item.savedAt)) continue;
+      if (evidence.length) {
+        await attachmentStore.put(item.id, {attachments:evidence.map(entry => ({
+          filename:String(entry.filename), contentType:String(entry.content_type),
+          blob:decodeBytes(String(entry.data), String(entry.content_type)),
+          ...(entry.note ? {note:String(entry.note)} : {}),
+        }))});
+      }
+      known.add(item.id);
+      imported.push(item);
+    }
+    if (imported.length) write(imported.concat(existing));
+    return imported.length;
+  }
+
+  return {list, capacity, save, replaceOldest, discard, resume, completeResume,
+    exportOwned, mergeRemote, currentLogin:getCurrentLogin,
+    subscribe:listener => (listeners.add(listener), () => listeners.delete(listener))};
 }
 
 if (typeof module !== 'undefined' && module.exports) module.exports = createUnfiledCaptures;

frontend/unfiled-draft-sync.js

@@ -0,0 +1,139 @@
+(function (root, factory) {
+  const createUnfiledDraftSync = factory();
+  if (typeof module === 'object' && module.exports) module.exports = createUnfiledDraftSync;
+  if (root) root.createUnfiledDraftSync = createUnfiledDraftSync;
+})(typeof globalThis !== 'undefined' ? globalThis : this, function () {
+  function createUnfiledDraftSync(options, mountedFetch) {
+    if (mountedFetch) return createUnfiledDraftSync.mount(options, mountedFetch);
+    const {captures, fetchJson, storage, getLogin = () => '', onState = () => {}} = options;
+    const key = 'stackchain.unfiled-draft-sync.v1';
+    let inFlight = null;
+    let rerun = false;
+
+    function read(login) {
+      try {
+        const all = JSON.parse(storage?.getItem(key) || '{}');
+        const state = all?.[login];
+        return {
+          all:all && typeof all === 'object' ? all : {},
+          known:new Set(Array.isArray(state?.known) ? state.known : []),
+          deleted:new Set(Array.isArray(state?.deleted) ? state.deleted : []),
+        };
+      } catch (_error) {
+        return {all:{}, known:new Set(), deleted:new Set()};
+      }
+    }
+
+    function write(login, state) {
+      state.all[login] = {known:[...state.known], deleted:[...state.deleted]};
+      storage?.setItem(key, JSON.stringify(state.all));
+    }
+
+    function publish(status, message) {
+      onState({status, ...(message ? {message} : {})});
+      const visibleStatus = globalThis.document?.querySelector?.('#my-work-action-status');
+      if (message && visibleStatus) visibleStatus.textContent = message;
+    }
+
+    function sameDrafts(left, right) {
+      return JSON.stringify(left) === JSON.stringify(right);
+    }
+
+    async function runSync(login) {
+      const owner = String(login || '').trim();
+      if (!owner) return false;
+      publish('syncing', 'Syncing Drafts…');
+      const state = read(owner);
+      try {
+        const remote = await fetchJson('api/v1/unfiled-drafts');
+        const remoteDrafts = Array.isArray(remote?.drafts) ? remote.drafts : [];
+        const remoteIds = new Set(remoteDrafts.map(item => item.id));
+        const before = await captures.exportOwned(owner);
+
+        for (const local of before) {
+          if (state.known.has(local.id) && !remoteIds.has(local.id) && !state.deleted.has(local.id)) {
+            await captures.discard(local.id);
+          }
+        }
+        await captures.mergeRemote(
+          remoteDrafts.filter(item => !state.deleted.has(item.id)), owner
+        );
+        const local = await captures.exportOwned(owner);
+        const merged = [];
+        const byId = new Map();
+        for (const item of remoteDrafts) if (!state.deleted.has(item.id)) byId.set(item.id, item);
+        for (const item of local) if (!state.deleted.has(item.id)) byId.set(item.id, item);
+        for (const item of byId.values()) merged.push(item);
+        merged.sort((left, right) => Number(right.saved_at) - Number(left.saved_at));
+
+        let finalSnapshot = remote;
+        if (!sameDrafts(merged, remoteDrafts)) {
+          finalSnapshot = await fetchJson('api/v1/unfiled-drafts', {
+            method:'PUT', headers:{'Content-Type':'application/json'},
+            body:JSON.stringify({revision:Number(remote.revision || 0), drafts:merged}),
+          });
+        }
+        state.known = new Set((finalSnapshot.drafts || []).map(item => item.id));
+        state.deleted.clear();
+        write(owner, state);
+        publish('ready', 'Drafts synced across devices.');
+        return true;
+      } catch (error) {
+        if (error?.status === 409) {
+          publish('conflict', 'Drafts changed on another device. Sync again to combine them.');
+        } else {
+          publish('pending', 'Saved on this device · sync pending');
+        }
+        throw error;
+      }
+    }
+
+    function sync(login) {
+      const owner = String(login || '').trim();
+      if (!owner) return Promise.resolve(false);
+      if (inFlight) {
+        rerun = true;
+        return inFlight;
+      }
+      inFlight = (async () => {
+        let result = false;
+        do {
+          rerun = false;
+          result = await runSync(owner);
+        } while (rerun);
+        return result;
+      })().finally(() => { inFlight = null; });
+      return inFlight;
+    }
+
+    async function remove(id, login) {
+      const owner = String(login || '').trim();
+      if (!owner) return false;
+      const state = read(owner);
+      state.deleted.add(String(id));
+      write(owner, state);
+      await captures.discard(String(id));
+      return sync(owner);
+    }
+
+    captures.subscribe?.((id, removed) => {
+      const login = getLogin();
+      if (login) void (removed ? remove(id, login) : sync(login)).catch(() => {});
+    });
+
+    return {sync, remove};
+  }
+  createUnfiledDraftSync.mount = (captures, fetchJson) => {
+    const getLogin = captures.currentLogin;
+    const controller = createUnfiledDraftSync({captures, fetchJson, storage:globalThis.localStorage, getLogin});
+    const connect = () => {
+      const login = getLogin();
+      if (login) void controller.sync(login).catch(() => {});
+      else globalThis.setTimeout(connect, 250);
+    };
+    globalThis.setTimeout(connect, 0);
+    globalThis.addEventListener?.('online', connect);
+    return controller;
+  };
+  return createUnfiledDraftSync;
+});