Sleeping rooms stay asleep across a restart

Idle rooms already went back to their ledgers, but a boot replayed
every ledger before the first sweep could put them to bed again — most
of a restart's fifteen seconds spent rebuilding games nobody was at.
A room put to sleep now leaves a stub beside the ledgers, with the
ledger's size at that moment; at boot a stub whose size still matches
answers for the room and the ledger stays unreplayed. Replayed rooms
take their eviction clock from the ledger's last line, so the first
sweep after a boot writes the stubs for everything long idle.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Jm2auWk6RP71CjaAb4FMoG

packages/server/src/rooms.ts

@@ -22,7 +22,7 @@ import {
   type PlayerId,
   CURRENT_RULES_REV,
 } from "@wizwar/engine";
-import { appendLine, archiveRoomFile, countRoomFiles, ensureDataDir, readAllRooms, readRoom, roomFileExists, type RoomLine } from "./store";
+import { appendLine, archiveRoomFile, countRoomFiles, ensureDataDir, ledgerStat, listRoomIds, readRoom, readStubFile, roomFileExists, writeStubFile, type RoomLine } from "./store";
 import { recordRoom } from "./stats";
 
 export interface LoggedCommand {
@@ -159,9 +159,16 @@ export function evictIdleRooms(hasSockets: (roomId: string) => boolean): number
     const idle = now - (room.touchedAt ?? now);
     const allowance = room.state?.phase === "finished" ? FINISHED_MS : IDLE_MS;
     if (idle < allowance) continue;
-    sleepingStubs.set(id, stubOf(room));
+    const stub = stubOf(room);
+    sleepingStubs.set(id, stub);
     rooms.delete(id);
     evicted++;
+    try {
+      const stat = ledgerStat(id);
+      if (stat) writeStubFile(id, stat.bytes, { ...stub, tokens: Object.fromEntries(stub.tokens) });
+    } catch (e) {
+      console.error(`could not write stub for ${id}:`, e);
+    }
   }
   return evicted;
 }
@@ -176,6 +183,8 @@ interface RoomStub {
   base: Omit<GameSummary, "name" | "yourTurn" | "attention">;
 }
 const sleepingStubs = new Map<string, RoomStub>();
+/** A stub as it rests on disk — the token map spelled as an object. */
+type StoredStub = Omit<RoomStub, "tokens"> & { tokens: Record<PlayerId, string> };
 
 function stubOf(room: Room): RoomStub {
   const { active, turnHolder, waitKind } = turnFacts(room.state);
@@ -775,14 +784,29 @@ function rebuildRoom(id: string, lines: RoomLine[]): Room | null {
   return room;
 }
 
-/** Rebuild every persisted room by replaying its file. */
+/** Bring the rooms back after a restart. A room whose stub still matches
+ * its ledger sleeps on, answering the games ledger from the stub; the
+ * rest are replayed, with the eviction clock set to their last line so
+ * the first sweep puts the long-idle ones back to bed. */
 export function loadPersistedRooms(): void {
   ensureDataDir();
   let restored = 0;
-  for (const [id, lines] of readAllRooms()) {
+  let asleep = 0;
+  for (const id of listRoomIds()) {
+    const stat = ledgerStat(id);
+    if (!stat) continue;
+    const stored = readStubFile<StoredStub>(id);
+    if (stored && stored.bytes === stat.bytes) {
+      sleepingStubs.set(id, { ...stored.stub, tokens: new Map(Object.entries(stored.stub.tokens)) });
+      asleep++;
+      continue;
+    }
+    const lines = readRoom(id);
+    if (!lines) continue;
     try {
       const room = rebuildRoom(id, lines);
       if (!room) continue;
+      room.touchedAt = stat.mtimeMs;
       rooms.set(id, room);
       recordRoom(room);
       restored++;
@@ -790,5 +814,5 @@ export function loadPersistedRooms(): void {
       console.error(`could not restore room ${id}:`, e);
     }
   }
-  if (restored > 0) console.log(`restored ${restored} room(s) from disk`);
+  if (restored + asleep > 0) console.log(`restored ${restored} room(s) from disk, ${asleep} left sleeping`);
 }