Restore mid-trickle acceleration when the canonical action lands

Co-authored-by: Marco Chávez <marcochavezf@users.noreply.github.com>

Author: MelvinBot

src/hooks/usePendingConciergeResponse.ts

@@ -1,7 +1,7 @@
 import {clearAgentZeroProcessingIndicator} from '@libs/actions/Report';
 import {applyPendingConciergeAction, clearPendingFollowupList, discardPendingConciergeAction, hidePendingFollowupList} from '@libs/actions/Report/SuggestedFollowup';
 import AgentZeroOptimisticStore, {MAX_AGE_MS} from '@libs/AgentZeroOptimisticStore';
-import {getOptimisticRevealDurationMS, MIN_TRICKLE_TOKEN_COUNT, TICK_INTERVAL_MS, TRICKLE_HARD_CAP_MS} from '@libs/ConciergeRevealUtils';
+import {ACCELERATED_REMAINING_MS, getOptimisticRevealDurationMS, MIN_TRICKLE_TOKEN_COUNT, TICK_INTERVAL_MS, TRICKLE_HARD_CAP_MS} from '@libs/ConciergeRevealUtils';
 import Log from '@libs/Log';
 import {rand64} from '@libs/NumberUtils';
 import type {ConciergeDraftEvent} from '@libs/Pusher/types';
@@ -46,6 +46,7 @@ function usePendingConciergeResponse(reportID: string | undefined) {
     const {dispatchLocalDraftEvent} = useConciergeDraftActions();
 
     const tokens = tokenizeForReveal(fullHtml);
+    const accelerateRef = useRef<((nowMs: number) => void) | null>(null);
 
     // Captured into a ref so the trickle effect can re-run only on the IDs that
     // identify a distinct Concierge reply. Composer typing, unrelated Onyx emits,
@@ -58,6 +59,16 @@ function usePendingConciergeResponse(reportID: string | undefined) {
         trickleInputsRef.current = {pendingResponse, fullHtml, tokens, dispatchLocalDraftEvent, persistedAction};
     });
 
+    // Reconciliation: when the canonical reportComment lands in REPORT_ACTIONS
+    // mid-trickle, fire the running loop's accelerator so the remaining reveal
+    // finishes in ~1.5s instead of snapping the synthetic bubble closed.
+    useEffect(() => {
+        if (!persistedAction || !accelerateRef.current) {
+            return;
+        }
+        accelerateRef.current(Date.now());
+    }, [persistedAction]);
+
     const lastOnlineTransitionAtRef = useRef<number>(0);
     const wasOfflineRef = useRef<boolean>(isOffline);
     useEffect(() => {
@@ -146,10 +157,16 @@ function usePendingConciergeResponse(reportID: string | undefined) {
         let sequence = 0;
         let intervalID: ReturnType<typeof setInterval> | null = null;
         let trickleStart = 0;
-        const effectiveDuration = getOptimisticRevealDurationMS(snapshotTokens.length);
+        // The accelerator recomputes effectiveDuration when the canonical reply lands
+        // so the tail finishes quickly.
+        let effectiveDuration = getOptimisticRevealDurationMS(snapshotTokens.length);
         let lastStage = 0;
         let cancelled = false;
         const clampProgress = (elapsedMs: number) => Math.max(0, Math.min(1, elapsedMs / effectiveDuration));
+        // Snapshot of trickle progress at the moment the canonical reportComment
+        // arrives. Presence (`arrival !== undefined`) doubles as the
+        // "acceleration fired" check that selects the completion reason below.
+        let arrival: {progress: number; elapsedMs: number} | undefined;
 
         const dispatch = (status: ConciergeDraftEvent['status'], finalRenderedHTML: string) => {
             if (cancelled) {
@@ -175,24 +192,46 @@ function usePendingConciergeResponse(reportID: string | undefined) {
                 intervalID = null;
             }
             const totalElapsedMs = trickleStart === 0 ? 0 : Date.now() - trickleStart;
-            const reason: 'natural' | 'stale_cap' = totalElapsedMs >= TRICKLE_HARD_CAP_MS ? 'stale_cap' : 'natural';
+            let reason: 'natural' | 'accelerated' | 'stale_cap' = 'natural';
+            if (arrival) {
+                reason = 'accelerated';
+            } else if (totalElapsedMs >= TRICKLE_HARD_CAP_MS) {
+                reason = 'stale_cap';
+            }
             Log.info('[ConciergeTrickle] complete', false, {
                 reportActionID,
                 reason,
                 tokenCount: snapshotTokens.length,
                 durationMs: effectiveDuration,
                 totalElapsedMs,
+                arrivedAtProgress: arrival?.progress,
+                arrivedAtElapsedMs: arrival?.elapsedMs,
             });
             dispatch('completed', snapshotTokens.at(-1) ?? snapshotHtml);
             // Don't reapply our older optimistic when the canonical is already there —
-            // Reapplying it would overwrite server-added follow-up buttons and deep-link Pressables.
-            if (trickleInputsRef.current.persistedAction) {
+            // it would clobber server-added markup (follow-up buttons, deep-link
+            // Pressables). `arrival` covers the accelerator path; the live ref read
+            // catches arrivals during the pre-trickle setTimeout where the accelerator
+            // no-ops on null intervalID.
+            if (arrival || trickleInputsRef.current.persistedAction) {
                 discardPendingConciergeAction(reportID);
             } else {
                 applyPendingConciergeAction(reportID, reportAction);
             }
         };
 
+        accelerateRef.current = (nowMs: number) => {
+            if (!intervalID || trickleStart === 0) {
+                return;
+            }
+            const elapsed = nowMs - trickleStart;
+            // Compressing effectiveDuration is what makes progress hit 1 within
+            // ACCELERATED_REMAINING_MS — the next tick observes progress >= 1
+            // and runs completeAndApply via the normal path.
+            arrival = {progress: clampProgress(elapsed), elapsedMs: elapsed};
+            effectiveDuration = elapsed + ACCELERATED_REMAINING_MS;
+        };
+
         const startTrickle = () => {
             if (cancelled) {
                 return;
@@ -242,6 +281,7 @@ function usePendingConciergeResponse(reportID: string | undefined) {
             if (intervalID) {
                 clearInterval(intervalID);
             }
+            accelerateRef.current = null;
         };
     }, [reportID, reportActionID]);
 }