wip(mobile): checkpoint the app shell and vision mockup in progress

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01VVYRAqiQj9Y1V9ZfG1RcDH

mobile/capture/db.js

@@ -0,0 +1,93 @@
+/** Minimal promise wrapper over the device's IndexedDB for keys and captures. */
+
+const DB_NAME = 'gev-mobile';
+const DB_VERSION = 1;
+let dbp = null;
+
+export function openDb() {
+  if (dbp) return dbp;
+  dbp = new Promise((resolve, reject) => {
+    if (!('indexedDB' in globalThis)) {
+      reject(new Error('IndexedDB is unavailable'));
+      return;
+    }
+    const req = indexedDB.open(DB_NAME, DB_VERSION);
+    req.onupgradeneeded = () => {
+      const db = req.result;
+      if (!db.objectStoreNames.contains('keys'))
+        db.createObjectStore('keys', { keyPath: 'id' });
+      if (!db.objectStoreNames.contains('captures')) {
+        const s = db.createObjectStore('captures', { keyPath: 'id' });
+        s.createIndex('seq', 'seq');
+      }
+      if (!db.objectStoreNames.contains('media'))
+        db.createObjectStore('media', { keyPath: 'id' });
+    };
+    req.onsuccess = () => resolve(req.result);
+    req.onerror = () => reject(req.error);
+  });
+  dbp.catch(() => (dbp = null));
+  return dbp;
+}
+
+function wrap(req) {
+  return new Promise((resolve, reject) => {
+    req.onsuccess = () => resolve(req.result);
+    req.onerror = () => reject(req.error);
+  });
+}
+
+export async function get(store, key) {
+  const db = await openDb();
+  return wrap(db.transaction(store).objectStore(store).get(key));
+}
+
+export async function put(store, value) {
+  const db = await openDb();
+  return wrap(db.transaction(store, 'readwrite').objectStore(store).put(value));
+}
+
+export async function del(store, key) {
+  const db = await openDb();
+  return wrap(
+    db.transaction(store, 'readwrite').objectStore(store).delete(key),
+  );
+}
+
+export async function all(store) {
+  const db = await openDb();
+  return wrap(db.transaction(store).objectStore(store).getAll());
+}
+
+/** Write a capture bundle and its media atomically. */
+export async function putCapture(bundle, mediaBlob) {
+  const db = await openDb();
+  return new Promise((resolve, reject) => {
+    const tx = db.transaction(['captures', 'media'], 'readwrite');
+    tx.objectStore('captures').put(bundle);
+    tx.objectStore('media').put({ id: bundle.id, blob: mediaBlob });
+    tx.oncomplete = () => resolve(bundle);
+    tx.onerror = () => reject(tx.error);
+    tx.onabort = () => reject(tx.error);
+  });
+}
+
+export async function lastCapture() {
+  const db = await openDb();
+  return new Promise((resolve, reject) => {
+    const req = db
+      .transaction('captures')
+      .objectStore('captures')
+      .index('seq')
+      .openCursor(null, 'prev');
+    req.onsuccess = () => resolve(req.result?.value || null);
+    req.onerror = () => reject(req.error);
+  });
+}
+
+export async function captureBySeq(seq) {
+  const db = await openDb();
+  return wrap(
+    db.transaction('captures').objectStore('captures').index('seq').get(seq),
+  );
+}