From b539ee9dc432499523d60f1a4c1b90101d97e8da Mon Sep 17 00:00:00 2001
From: Wrench
 <0eabe6ea5758c1e4c5b68cea4ac42b32c479072883cb28da8110b4a47c32b9a1@buzz.block.builderlab.xyz>
Date: Tue, 25 Aug 2026 18:51:09 -0400
Subject: [PATCH] fix(projects): bound channel request queue

Co-authored-by: Wrench <0eabe6ea5758c1e4c5b68cea4ac42b32c479072883cb28da8110b4a47c32b9a1@buzz.block.builderlab.xyz>
Signed-off-by: Wrench <0eabe6ea5758c1e4c5b68cea4ac42b32c479072883cb28da8110b4a47c32b9a1@buzz.block.builderlab.xyz>
---
 .../projectChannelRequestQueue.test.mjs       | 62 +++++++++++++++++--
 .../projects/projectChannelRequestQueue.ts    | 44 +++++++++++--
 .../projects/useProjectChannelRequests.ts     |  4 +-
 3 files changed, 100 insertions(+), 10 deletions(-)

diff --git a/desktop/src/features/projects/projectChannelRequestQueue.test.mjs b/desktop/src/features/projects/projectChannelRequestQueue.test.mjs
index 1fd49cd98b..4b1bfebc96 100644
--- a/desktop/src/features/projects/projectChannelRequestQueue.test.mjs
+++ b/desktop/src/features/projects/projectChannelRequestQueue.test.mjs
@@ -5,6 +5,7 @@ import {
   advanceProjectChannelRequestQueue,
   createProjectChannelRequestQueue,
   enqueueProjectChannelRequest,
+  MAX_PENDING_PROJECT_CHANNEL_REQUESTS,
 } from "./projectChannelRequestQueue.ts";
 
 function candidate(requestId) {
@@ -19,10 +20,63 @@ test("accepted requests advance in order while duplicate active requests stay su
   const first = candidate("request-a");
   const second = candidate("request-b");
 
-  assert.equal(enqueueProjectChannelRequest(queue, first), first);
-  assert.equal(enqueueProjectChannelRequest(queue, second), null);
-  assert.equal(enqueueProjectChannelRequest(queue, first), null);
+  assert.deepEqual(enqueueProjectChannelRequest(queue, first), {
+    status: "show",
+    candidate: first,
+  });
+  assert.deepEqual(enqueueProjectChannelRequest(queue, second), {
+    status: "queued",
+  });
+  assert.deepEqual(enqueueProjectChannelRequest(queue, first), {
+    status: "duplicate",
+  });
   assert.equal(advanceProjectChannelRequestQueue(queue), second);
-  assert.equal(enqueueProjectChannelRequest(queue, first), null);
+  assert.deepEqual(enqueueProjectChannelRequest(queue, first), {
+    status: "duplicate",
+  });
   assert.equal(advanceProjectChannelRequestQueue(queue), null);
 });
+
+test("accepted queue drops newest overflow while preserving FIFO and retryability", () => {
+  const queue = createProjectChannelRequestQueue();
+  const first = candidate("request-0");
+  assert.equal(enqueueProjectChannelRequest(queue, first).status, "show");
+
+  const pending = Array.from(
+    { length: MAX_PENDING_PROJECT_CHANNEL_REQUESTS },
+    (_, index) => candidate(`request-${index + 1}`),
+  );
+  for (const request of pending) {
+    assert.equal(enqueueProjectChannelRequest(queue, request).status, "queued");
+  }
+
+  const overflow = candidate("request-overflow");
+  assert.deepEqual(enqueueProjectChannelRequest(queue, overflow), {
+    status: "overflow",
+  });
+  assert.equal(queue.pending.length, MAX_PENDING_PROJECT_CHANNEL_REQUESTS);
+  assert.equal(queue.seenRequestIds.has(overflow.request.requestId), false);
+
+  for (const request of pending) {
+    assert.equal(advanceProjectChannelRequestQueue(queue), request);
+  }
+  assert.equal(advanceProjectChannelRequestQueue(queue), null);
+  assert.deepEqual(enqueueProjectChannelRequest(queue, overflow), {
+    status: "show",
+    candidate: overflow,
+  });
+});
+
+test("dedup history stays bounded without forgetting active or pending requests", () => {
+  const queue = createProjectChannelRequestQueue();
+  for (let index = 0; index < 500; index += 1) {
+    const request = candidate(`request-${index}`);
+    assert.equal(enqueueProjectChannelRequest(queue, request).status, "show");
+    assert.deepEqual(enqueueProjectChannelRequest(queue, request), {
+      status: "duplicate",
+    });
+    assert.equal(advanceProjectChannelRequestQueue(queue), null);
+  }
+
+  assert.ok(queue.seenRequestIds.size <= 201);
+});
diff --git a/desktop/src/features/projects/projectChannelRequestQueue.ts b/desktop/src/features/projects/projectChannelRequestQueue.ts
index 24fc3a5ecb..7fd587a4d8 100644
--- a/desktop/src/features/projects/projectChannelRequestQueue.ts
+++ b/desktop/src/features/projects/projectChannelRequestQueue.ts
@@ -1,5 +1,9 @@
 import type { ProjectChannelRequest } from "@/features/projects/projectChannelRequest";
 
+export const MAX_PENDING_PROJECT_CHANNEL_REQUESTS = 100;
+const MAX_SEEN_PROJECT_CHANNEL_REQUEST_IDS =
+  MAX_PENDING_PROJECT_CHANNEL_REQUESTS * 2 + 1;
+
 export type AcceptedProjectChannelRequest = {
   agentPubkey: string;
   request: ProjectChannelRequest;
@@ -11,6 +15,10 @@ export type ProjectChannelRequestQueue = {
   seenRequestIds: Set<string>;
 };
 
+export type EnqueueProjectChannelRequestResult =
+  | { status: "show"; candidate: AcceptedProjectChannelRequest }
+  | { status: "queued" | "duplicate" | "overflow" };
+
 export function createProjectChannelRequestQueue(): ProjectChannelRequestQueue {
   return {
     activeRequestId: null,
@@ -22,18 +30,29 @@ export function createProjectChannelRequestQueue(): ProjectChannelRequestQueue {
 export function enqueueProjectChannelRequest(
   queue: ProjectChannelRequestQueue,
   candidate: AcceptedProjectChannelRequest,
-): AcceptedProjectChannelRequest | null {
+): EnqueueProjectChannelRequestResult {
   const requestId = candidate.request.requestId;
-  if (queue.seenRequestIds.has(requestId)) return null;
+  if (queue.seenRequestIds.has(requestId)) return { status: "duplicate" };
+
+  if (
+    queue.activeRequestId !== null &&
+    queue.pending.length >= MAX_PENDING_PROJECT_CHANNEL_REQUESTS
+  ) {
+    // Keep the requests already visible to the owner and drop the newest one.
+    // Do not mark it seen: a later retry may be accepted after space opens.
+    return { status: "overflow" };
+  }
+
   queue.seenRequestIds.add(requestId);
+  pruneSeenRequestIds(queue);
 
   if (queue.activeRequestId === null) {
     queue.activeRequestId = requestId;
-    return candidate;
+    return { status: "show", candidate };
   }
 
   queue.pending.push(candidate);
-  return null;
+  return { status: "queued" };
 }
 
 export function advanceProjectChannelRequestQueue(
@@ -41,5 +60,22 @@ export function advanceProjectChannelRequestQueue(
 ): AcceptedProjectChannelRequest | null {
   const next = queue.pending.shift() ?? null;
   queue.activeRequestId = next?.request.requestId ?? null;
+  pruneSeenRequestIds(queue);
   return next;
 }
+
+function pruneSeenRequestIds(queue: ProjectChannelRequestQueue) {
+  if (queue.seenRequestIds.size <= MAX_SEEN_PROJECT_CHANNEL_REQUEST_IDS) return;
+
+  const pendingIds = new Set(
+    queue.pending.map((candidate) => candidate.request.requestId),
+  );
+  for (const requestId of queue.seenRequestIds) {
+    if (requestId !== queue.activeRequestId && !pendingIds.has(requestId)) {
+      queue.seenRequestIds.delete(requestId);
+      if (queue.seenRequestIds.size <= MAX_SEEN_PROJECT_CHANNEL_REQUEST_IDS) {
+        return;
+      }
+    }
+  }
+}
diff --git a/desktop/src/features/projects/useProjectChannelRequests.ts b/desktop/src/features/projects/useProjectChannelRequests.ts
index 371bb1a9c1..8c95ff15c7 100644
--- a/desktop/src/features/projects/useProjectChannelRequests.ts
+++ b/desktop/src/features/projects/useProjectChannelRequests.ts
@@ -51,11 +51,11 @@ export function useProjectChannelRequests() {
       ) {
         return;
       }
-      const accepted = enqueueProjectChannelRequest(acceptedRequests.current, {
+      const result = enqueueProjectChannelRequest(acceptedRequests.current, {
         agentPubkey,
         request: next,
       });
-      if (accepted) showRequest(accepted);
+      if (result.status === "show") showRequest(result.candidate);
     },
   );