From 24dd7aec90c00fb1096f47c383b254ce9e83e076 Mon Sep 17 00:00:00 2001
From: Tak Hoffman <781889+Takhoffman@users.noreply.github.com>
Date: Thu, 26 Mar 2026 10:01:45 -0500
Subject: [PATCH] fix: prefer freshest duplicate store matches

---
 src/gateway/session-utils.test.ts | 51 +++++++++++++++++++++++++++++++
 src/gateway/session-utils.ts      | 40 +++++++++++++-----------
 2 files changed, 73 insertions(+), 18 deletions(-)

diff --git a/src/gateway/session-utils.test.ts b/src/gateway/session-utils.test.ts
index 9745abf26b3..bd20aa7ebac 100644
--- a/src/gateway/session-utils.test.ts
+++ b/src/gateway/session-utils.test.ts
@@ -375,6 +375,57 @@ describe("gateway session utils", () => {
     }
   });
 
+  test("loadSessionEntry prefers the freshest duplicate row across discovered stores", async () => {
+    clearConfigCache();
+    try {
+      await withStateDirEnv("session-utils-load-entry-cross-store-", async ({ stateDir }) => {
+        const canonicalSessionsDir = path.join(stateDir, "agents", "main", "sessions");
+        fs.mkdirSync(canonicalSessionsDir, { recursive: true });
+        fs.writeFileSync(
+          path.join(canonicalSessionsDir, "sessions.json"),
+          JSON.stringify(
+            {
+              "agent:main:main": { sessionId: "sess-canonical-stale", updatedAt: 10 },
+              "agent:main:MAIN": { sessionId: "sess-canonical-fresh", updatedAt: 1000 },
+            },
+            null,
+            2,
+          ),
+          "utf8",
+        );
+
+        const discoveredSessionsDir = path.join(stateDir, "agents", "main ", "sessions");
+        fs.mkdirSync(discoveredSessionsDir, { recursive: true });
+        fs.writeFileSync(
+          path.join(discoveredSessionsDir, "sessions.json"),
+          JSON.stringify(
+            {
+              "agent:main:main": { sessionId: "sess-discovered-mid", updatedAt: 500 },
+            },
+            null,
+            2,
+          ),
+          "utf8",
+        );
+
+        await writeConfigFile({
+          session: {
+            mainKey: "main",
+            store: path.join(stateDir, "agents", "{agentId}", "sessions", "sessions.json"),
+          },
+          agents: { list: [{ id: "main", default: true }] },
+        });
+        clearConfigCache();
+
+        const loaded = loadSessionEntry("agent:main:main");
+
+        expect(loaded.entry?.sessionId).toBe("sess-canonical-fresh");
+      });
+    } finally {
+      clearConfigCache();
+    }
+  });
+
   test("pruneLegacyStoreKeys removes alias and case-variant ghost keys", () => {
     const store: Record<string, unknown> = {
       "agent:ops:work": { sessionId: "canonical", updatedAt: 3 },
diff --git a/src/gateway/session-utils.ts b/src/gateway/session-utils.ts
index ae09e8ce24f..e23b1feeca5 100644
--- a/src/gateway/session-utils.ts
+++ b/src/gateway/session-utils.ts
@@ -399,29 +399,33 @@ export function resolveFreshestSessionEntryFromStoreKeys(
   return resolveFreshestSessionStoreMatchFromStoreKeys(store, storeKeys)?.entry;
 }
 
-/**
- * Find a session entry by exact or case-insensitive key match.
- * Returns both the entry and the actual store key it was found under,
- * so callers can clean up legacy mixed-case keys when they differ from canonicalKey.
- */
-function findStoreMatch(
+function findFreshestStoreMatch(
   store: Record<string, SessionEntry>,
   ...candidates: string[]
 ): { entry: SessionEntry; key: string } | undefined {
-  // Exact match first.
+  const matches = new Map<string, { entry: SessionEntry; key: string }>();
   for (const candidate of candidates) {
-    if (candidate && store[candidate]) {
-      return { entry: store[candidate], key: candidate };
+    const trimmed = candidate.trim();
+    if (!trimmed) {
+      continue;
+    }
+    const exact = store[trimmed];
+    if (exact) {
+      matches.set(trimmed, { entry: exact, key: trimmed });
+    }
+    for (const key of findStoreKeysIgnoreCase(store, trimmed)) {
+      const entry = store[key];
+      if (entry) {
+        matches.set(key, { entry, key });
+      }
     }
   }
-  // Case-insensitive scan for ALL candidates.
-  const loweredSet = new Set(candidates.filter(Boolean).map((c) => c.toLowerCase()));
-  for (const key of Object.keys(store)) {
-    if (loweredSet.has(key.toLowerCase())) {
-      return { entry: store[key], key };
-    }
+  if (matches.size === 0) {
+    return undefined;
   }
-  return undefined;
+  return [...matches.values()].toSorted(
+    (a, b) => (b.entry.updatedAt ?? 0) - (a.entry.updatedAt ?? 0),
+  )[0];
 }
 
 /**
@@ -782,7 +786,7 @@ function resolveGatewaySessionStoreLookup(params: {
   };
   let selectedStorePath = fallback.storePath;
   let selectedStore = params.initialStore ?? loadSessionStore(fallback.storePath);
-  let selectedMatch = findStoreMatch(selectedStore, ...scanTargets);
+  let selectedMatch = findFreshestStoreMatch(selectedStore, ...scanTargets);
   let selectedUpdatedAt = selectedMatch?.entry.updatedAt ?? Number.NEGATIVE_INFINITY;
 
   for (let index = 1; index < candidates.length; index += 1) {
@@ -791,7 +795,7 @@ function resolveGatewaySessionStoreLookup(params: {
       continue;
     }
     const store = loadSessionStore(candidate.storePath);
-    const match = findStoreMatch(store, ...scanTargets);
+    const match = findFreshestStoreMatch(store, ...scanTargets);
     if (!match) {
       continue;
     }