restructure js bindings

bindings/javascript/packages/browser/promise.ts

@@ -0,0 +1,78 @@
+import { DatabasePromise, NativeDatabase, DatabaseOpts, SqliteError } from "@tursodatabase/database-core"
+import { connect as nativeConnect, initThreadPool, MainWorker } from "./index.js";
+
+let workerRequestId = 0;
+class Database extends DatabasePromise {
+    files: string[];
+    constructor(db: NativeDatabase, files: string[], opts: DatabaseOpts = {}) {
+        super(db, opts)
+        this.files = files;
+    }
+    async close() {
+        let currentId = workerRequestId;
+        workerRequestId += this.files.length;
+
+        let tasks = [];
+        for (const file of this.files) {
+            (MainWorker as any).postMessage({ __turso__: "unregister", path: file, id: currentId });
+            tasks.push(waitFor(currentId));
+            currentId += 1;
+        }
+        await Promise.all(tasks);
+        this.db.close();
+    }
+}
+
+function waitFor(id: number): Promise<any> {
+    let waitResolve, waitReject;
+    const callback = msg => {
+        if (msg.data.id == id) {
+            if (msg.data.error != null) {
+                waitReject(msg.data.error)
+            } else {
+                waitResolve()
+            }
+            cleanup();
+        }
+    };
+    const cleanup = () => (MainWorker as any).removeEventListener("message", callback);
+
+    (MainWorker as any).addEventListener("message", callback);
+    const result = new Promise((resolve, reject) => {
+        waitResolve = resolve;
+        waitReject = reject;
+    });
+    return result;
+}
+
+/**
+ * Creates a new database connection asynchronously.
+ * 
+ * @param {string} path - Path to the database file.
+ * @param {Object} opts - Options for database behavior.
+ * @returns {Promise<Database>} - A promise that resolves to a Database instance.
+ */
+async function connect(path: string, opts: DatabaseOpts = {}): Promise<Database> {
+    if (path == ":memory:") {
+        const db = await nativeConnect(path, { tracing: opts.tracing });
+        return new Database(db, [], opts);
+    }
+    await initThreadPool();
+    if (MainWorker == null) {
+        throw new Error("panic: MainWorker is not set");
+    }
+
+    let currentId = workerRequestId;
+    workerRequestId += 2;
+
+    let dbHandlePromise = waitFor(currentId);
+    let walHandlePromise = waitFor(currentId + 1);
+    (MainWorker as any).postMessage({ __turso__: "register", path: `${path}`, id: currentId });
+    (MainWorker as any).postMessage({ __turso__: "register", path: `${path}-wal`, id: currentId + 1 });
+    await Promise.all([dbHandlePromise, walHandlePromise]);
+    const db = await nativeConnect(path, { tracing: opts.tracing });
+    const files = [path, `${path}-wal`];
+    return new Database(db, files, opts);
+}
+
+export { connect, Database, SqliteError }