Initial commit: QwenClaw persistent daemon for Qwen Code

src/sessions.ts

@@ -0,0 +1,87 @@
+import { join } from "path";
+import { unlink, readdir, rename } from "fs/promises";
+
+const HEARTBEAT_DIR = join(process.cwd(), ".qwen", "qwenclaw");
+const SESSION_FILE = join(HEARTBEAT_DIR, "session.json");
+
+export interface GlobalSession {
+  sessionId: string;
+  createdAt: string;
+  lastUsedAt: string;
+}
+
+let current: GlobalSession | null = null;
+
+async function loadSession(): Promise<GlobalSession | null> {
+  if (current) return current;
+  try {
+    current = await Bun.file(SESSION_FILE).json();
+    return current;
+  } catch {
+    return null;
+  }
+}
+
+async function saveSession(session: GlobalSession): Promise<void> {
+  current = session;
+  await Bun.write(SESSION_FILE, JSON.stringify(session, null, 2) + "\n");
+}
+
+/** Returns the existing session or null. Never creates one. */
+export async function getSession(): Promise<{ sessionId: string } | null> {
+  const existing = await loadSession();
+  if (existing) {
+    existing.lastUsedAt = new Date().toISOString();
+    await saveSession(existing);
+    return { sessionId: existing.sessionId };
+  }
+  return null;
+}
+
+/** Save a session ID obtained from Qwen's output. */
+export async function createSession(sessionId: string): Promise<void> {
+  await saveSession({
+    sessionId,
+    createdAt: new Date().toISOString(),
+    lastUsedAt: new Date().toISOString(),
+  });
+}
+
+/** Returns session metadata without mutating lastUsedAt. */
+export async function peekSession(): Promise<GlobalSession | null> {
+  return await loadSession();
+}
+
+export async function resetSession(): Promise<void> {
+  current = null;
+  try {
+    await unlink(SESSION_FILE);
+  } catch {
+    // already gone
+  }
+}
+
+export async function backupSession(): Promise<string | null> {
+  const existing = await loadSession();
+  if (!existing) return null;
+
+  // Find next backup index
+  let files: string[];
+  try {
+    files = await readdir(HEARTBEAT_DIR);
+  } catch {
+    files = [];
+  }
+
+  const indices = files
+    .filter((f) => /^session_\d+\.backup$/.test(f))
+    .map((f) => Number(f.match(/^session_(\d+)\.backup$/)![1]));
+
+  const nextIndex = indices.length > 0 ? Math.max(...indices) + 1 : 1;
+  const backupName = `session_${nextIndex}.backup`;
+  const backupPath = join(HEARTBEAT_DIR, backupName);
+
+  await rename(SESSION_FILE, backupPath);
+  current = null;
+  return backupName;
+}