Save chats, messages and media to IndexedDB

js/db.js

@@ -0,0 +1,204 @@
+const DB_NAME = "pandora";
+const DB_VERSION = 6;
+let dbPromise = null;
+
+function normalizeId(raw) {
+  if (!raw) return null;
+  if (typeof raw === 'object') {
+    return raw._serialized || raw.user || JSON.stringify(raw);
+  }
+  return raw;
+}
+
+function openDb() {
+  if (dbPromise) return dbPromise;
+
+  dbPromise = new Promise((resolve, reject) => {
+    const req = indexedDB.open(DB_NAME, DB_VERSION);
+
+    req.onupgradeneeded = (e) => {
+      const db = req.result;
+      const tx = req.transaction;
+
+      if (!db.objectStoreNames.contains("chats")) {
+        const store = db.createObjectStore("chats", { keyPath: "id" });
+        store.createIndex("timestamp", "timestamp", { unique: false });
+      }
+
+      let msgStore;
+      if (!db.objectStoreNames.contains("messages")) {
+        msgStore = db.createObjectStore("messages", { keyPath: "id" });
+        msgStore.createIndex("from", "from", { unique: false });
+        msgStore.createIndex("fingerprint", ["from", "timestamp"], { unique: false });
+      } else {
+        msgStore = tx.objectStore("messages");
+      }
+
+      if (!msgStore.indexNames.contains("chatId_timestamp")) {
+        msgStore.createIndex("chatId_timestamp", ["chatId", "timestamp"], { unique: false });
+      }
+
+      if (db.objectStoreNames.contains("messages")) {
+        msgStore.openCursor().onsuccess = (event) => {
+          const cursor = event.target.result;
+          if (cursor) {
+            const m = cursor.value;
+            const from = normalizeId(m.from);
+            const to = normalizeId(m.to);
+            const chatId = normalizeId(m.chatId) || (m.fromMe ? to : from);
+            if (!m.chatId && chatId) {
+              m.chatId = chatId;
+              cursor.update(m);
+            }
+            cursor.continue();
+          }
+        };
+      }
+
+      if (!db.objectStoreNames.contains("media")) {
+        db.createObjectStore("media", { keyPath: "reqId" });
+      }
+    };
+
+    req.onsuccess = () => resolve(req.result);
+    req.onerror = () => reject(req.error);
+  });
+
+  return dbPromise;
+}
+
+export async function upsertChats(chats) {
+  const db = await openDb();
+
+  return new Promise((resolve, reject) => {
+    const tx = db.transaction("chats", "readwrite");
+    const store = tx.objectStore("chats");
+
+    for (const c of chats) {
+      store.put({
+        id: c.id,
+        name: c.name,
+        lastMessage: c.lastMessage,
+        timestamp: c.timestamp,
+        unreadCount: c.unreadCount ?? 0
+      });
+    }
+
+    tx.oncomplete = () => resolve();
+    tx.onerror = () => reject(tx.error);
+  });
+}
+
+export async function loadChatsSorted() {
+  const db = await openDb();
+
+  return new Promise((resolve, reject) => {
+    const tx = db.transaction("chats", "readonly");
+    const store = tx.objectStore("chats");
+    const idx = store.index("timestamp");
+
+    const result = [];
+    idx.openCursor(null, "prev").onsuccess = (e) => {
+      const cursor = e.target.result;
+      if (cursor) {
+        result.push(cursor.value);
+        cursor.continue();
+      } else {
+        resolve(result);
+      }
+    };
+
+    tx.onerror = () => reject(tx.error);
+  });
+}
+
+function mapMessage(m) {
+  const from = normalizeId(m.from);
+  const to = normalizeId(m.to);
+  const chatId = normalizeId(m.chatId) || (m.fromMe ? to : from);
+
+  return {
+    _data: m._data,
+    id: m.id,
+    timestamp: m.timestamp,
+    body: m.body,
+    from: from,
+    fromMe: m.fromMe,
+    ack: m.ack,
+    hasMedia: m.hasMedia,
+    media: m.media,
+    chatId: chatId,
+  }
+}
+
+export async function upsertMessages(messages) {
+  const db = await openDb();
+
+  return new Promise((resolve, reject) => {
+    const tx = db.transaction("messages", "readwrite");
+    const store = tx.objectStore("messages");
+
+    for (const m of messages) {
+      store.put(mapMessage(m));
+    }
+
+    tx.oncomplete = () => resolve();
+    tx.onerror = () => reject(tx.error);
+  });
+}
+
+export async function loadLatestMessages(chatId, limit = 50) {
+  const db = await openDb();
+
+  return new Promise((resolve, reject) => {
+    const tx = db.transaction("messages", "readonly");
+    const store = tx.objectStore("messages");
+    const idx = store.index("chatId_timestamp");
+
+    const out = [];
+
+    const range = IDBKeyRange.bound([chatId, -Infinity], [chatId, Infinity]);
+
+    idx.openCursor(range, "prev").onsuccess = (e) => {
+      const cursor = e.target.result;
+      if (!cursor) return resolve(out);
+
+      out.push(cursor.value);
+      if (out.length >= limit) resolve(out);
+      else cursor.continue();
+    };
+
+    tx.onerror = () => reject(tx.error);
+  });
+}
+
+export async function upsertMedia(reqId, blob, filename) {
+  const db = await openDb();
+
+  return new Promise((resolve, reject) => {
+    const tx = db.transaction("media", "readwrite");
+    const store = tx.objectStore("media");
+
+    store.put({
+      reqId: reqId,
+      blob: blob,
+      filename: filename
+    });
+
+    tx.oncomplete = () => resolve();
+    tx.onerror = () => reject(tx.error);
+  });
+}
+
+export async function loadMedia(reqId) {
+  const db = await openDb();
+
+  return new Promise((resolve, reject) => {
+    const tx = db.transaction("media", "readonly");
+    const store = tx.objectStore("media");
+    const req = store.get(reqId);
+
+    req.onsuccess = () => resolve(req.result);
+    req.onerror = () => reject(req.error);
+  });
+}