fix: add progress logging during silent render pipeline stages (#1220)

* fix: add progress logging during silent render pipeline stages The render pipeline only updates progress at stage boundaries (5%, 10%, 25%), leaving multi-minute gaps with zero log output on low-memory hardware. This adds log.info calls at key sub-steps within the three silent stages: - Probe stage (5%): browser launch, session initialization, duration discovery, media asset discovery, audio volume automation, video visibility window detection - Video extraction (10%): per-video extraction progress - Calibration (25%): browser launch, session initialization, per-frame calibration progress, final cost estimate Also adds 30-second heartbeat timers for the two initializeSession calls (probe and calibration) that can individually take minutes on constrained hardware. Closes #1218 * fix: resolve CI failures in typecheck, runtime seek test, and timeline test - Make handleGsapMaterializeKeyframes optional in DomEditSessionSlice and use optional chaining at the call site (not yet wired) - Update GSAP adapter seek test to expect nudge+seek pattern (totalTime with suppressEvents:true followed by actual seek) - Fix Timeline canvas height test to use TRACK_H constant (48) instead of stale hardcoded value (72) * refactor: extract helpers to meet 600-line file size limit - App.tsx (603→594): extract StudioToast component - useDomEditSession.ts (688→600): extract useGsapSelectionHandlers hook - Timeline.tsx (614→557): extract useTimelineAssetDrop hook - PropertyPanel.tsx (647→584): extract TimingSection to propertyPanelTimingSection * style: fix formatting in TimelineToolbar
2026-09-03 23:03:09 +00:00 · 2026-06-05 16:17:58 -04:00
parent 20894ab9a3
commit 6bd1e764e5
14 changed files with 503 additions and 277 deletions
@@ -44,6 +44,7 @@ import { PanelLayoutProvider } from "./contexts/PanelLayoutContext";
 import { FileManagerProvider } from "./contexts/FileManagerContext";
 import { DomEditProvider } from "./contexts/DomEditContext";
 import { StudioSplash } from "./components/StudioSplash";
+import { StudioToast } from "./components/StudioToast";
 import { useServerConnection } from "./hooks/useServerConnection";
 import {
  normalizeStudioCompositionPath,
@@ -583,17 +584,7 @@ export function StudioApp() {
              )}

              {dragOverlay.active && <StudioGlobalDragOverlay />}
-              {appToast && (
-                <div
-                  className={`absolute bottom-6 left-1/2 -translate-x-1/2 z-[91] px-4 py-2 rounded-lg border text-sm shadow-lg animate-in fade-in slide-in-from-bottom-2 ${
-                    appToast.tone === "error"
-                      ? "bg-red-900/90 border-red-700/50 text-red-200"
-                      : "bg-neutral-900/95 border-neutral-700/60 text-neutral-100"
-                  }`}
-                >
-                  {appToast.message}
-                </div>
-              )}
+              {appToast && <StudioToast message={appToast.message} tone={appToast.tone} />}
            </div>
          </DomEditProvider>
        </FileManagerProvider>
@@ -0,0 +1,18 @@
+interface StudioToastProps {
+  message: string;
+  tone?: "error" | "info";
+}
+
+export function StudioToast({ message, tone }: StudioToastProps) {
+  return (
+    <div
+      className={`absolute bottom-6 left-1/2 -translate-x-1/2 z-[91] px-4 py-2 rounded-lg border text-sm shadow-lg animate-in fade-in slide-in-from-bottom-2 ${
+        tone === "error"
+          ? "bg-red-900/90 border-red-700/50 text-red-200"
+          : "bg-neutral-900/95 border-neutral-700/60 text-neutral-100"
+      }`}
+    >
+      {message}
+    </div>
+  );
+}
@@ -125,8 +125,8 @@ function useKeyframeToggle(session?: DomEditSessionSlice) {
    ? async () => {
        const t = usePlayerStore.getState().currentTime;
        if (kfAnim?.keyframes) {
-          if (kfAnim.hasUnresolvedKeyframes && session.handleGsapMaterializeKeyframes) {
-            await session.handleGsapMaterializeKeyframes(kfAnim.id);
+          if (kfAnim.hasUnresolvedKeyframes) {
+            await session.handleGsapMaterializeKeyframes?.(kfAnim.id);
          }
          const elStart = Number.parseFloat(sel.dataAttributes?.start ?? "0") || 0;
          const elDuration = Number.parseFloat(sel.dataAttributes?.duration ?? "1") || 1;
@@ -1,5 +1,5 @@
 import { memo } from "react";
-import { Clock, Eye, Layers, MessageSquare, Move, X } from "../../icons/SystemIcons";
+import { Eye, Layers, MessageSquare, Move, X } from "../../icons/SystemIcons";
 import { type DomEditSelection } from "./domEditing";
 import { readStudioBoxSize, readStudioPathOffset, readStudioRotation } from "./manualEdits";
 import type { ImportedFontAsset } from "./fontAssets";
@@ -13,6 +13,7 @@ import {
 import { MetricField, Section } from "./propertyPanelPrimitives";
 import { isMediaElement, MediaSection } from "./propertyPanelMediaSection";
 import { TextSection, StyleSections } from "./propertyPanelSections";
+import { TimingSection } from "./propertyPanelTimingSection";
 import { GsapAnimationSection } from "./GsapAnimationSection";
 import { KeyframeNavigation } from "./KeyframeNavigation";
 import { STUDIO_GSAP_PANEL_ENABLED, STUDIO_KEYFRAMES_ENABLED } from "./manualEditingAvailability";
@@ -84,70 +85,6 @@ interface PropertyPanelProps {
  onSeekToTime?: (time: number) => void;
 }

-/* ------------------------------------------------------------------ */
-/*  TimingSection                                                      */
-/* ------------------------------------------------------------------ */
-
-function formatTimingValue(seconds: number): string {
-  if (!Number.isFinite(seconds) || seconds < 0) return "0.00s";
-  return `${seconds.toFixed(2)}s`;
-}
-
-function parseTimingValue(input: string): number | null {
-  const cleaned = input.replace(/s$/i, "").trim();
-  const parsed = Number.parseFloat(cleaned);
-  return Number.isFinite(parsed) && parsed >= 0 ? parsed : null;
-}
-
-function TimingSection({
-  element,
-  onSetAttribute,
-}: {
-  element: DomEditSelection;
-  onSetAttribute: (attr: string, value: string) => void | Promise<void>;
-}) {
-  const start = Number.parseFloat(element.dataAttributes.start ?? "0") || 0;
-  const duration =
-    Number.parseFloat(
-      element.dataAttributes.duration ?? element.dataAttributes["hf-authored-duration"] ?? "0",
-    ) || 0;
-  const end = start + duration;
-
-  const commitStart = (nextValue: string) => {
-    const parsed = parseTimingValue(nextValue);
-    if (parsed == null) return;
-    void onSetAttribute("start", parsed.toFixed(2));
-  };
-
-  const commitDuration = (nextValue: string) => {
-    const parsed = parseTimingValue(nextValue);
-    if (parsed == null || parsed <= 0) return;
-    void onSetAttribute("duration", parsed.toFixed(2));
-  };
-
-  const commitEnd = (nextValue: string) => {
-    const parsed = parseTimingValue(nextValue);
-    if (parsed == null || parsed <= start) return;
-    void onSetAttribute("duration", (parsed - start).toFixed(2));
-  };
-
-  return (
-    <Section title="Timing" icon={<Clock size={15} />}>
-      <div className={RESPONSIVE_GRID}>
-        <MetricField label="Start" value={formatTimingValue(start)} onCommit={commitStart} />
-        <MetricField label="End" value={formatTimingValue(end)} onCommit={commitEnd} />
-      </div>
-      <div className="mt-3">
-        <MetricField
-          label="Duration"
-          value={formatTimingValue(duration)}
-          onCommit={commitDuration}
-        />
-      </div>
-    </Section>
-  );
-}
-
 /* ------------------------------------------------------------------ */
 /*  PropertyPanel                                                      */
 /* ------------------------------------------------------------------ */
@@ -0,0 +1,64 @@
+import { Clock } from "../../icons/SystemIcons";
+import type { DomEditSelection } from "./domEditing";
+import { RESPONSIVE_GRID } from "./propertyPanelHelpers";
+import { MetricField, Section } from "./propertyPanelPrimitives";
+
+function formatTimingValue(seconds: number): string {
+  if (!Number.isFinite(seconds) || seconds < 0) return "0.00s";
+  return `${seconds.toFixed(2)}s`;
+}
+
+function parseTimingValue(input: string): number | null {
+  const cleaned = input.replace(/s$/i, "").trim();
+  const parsed = Number.parseFloat(cleaned);
+  return Number.isFinite(parsed) && parsed >= 0 ? parsed : null;
+}
+
+export function TimingSection({
+  element,
+  onSetAttribute,
+}: {
+  element: DomEditSelection;
+  onSetAttribute: (attr: string, value: string) => void | Promise<void>;
+}) {
+  const start = Number.parseFloat(element.dataAttributes.start ?? "0") || 0;
+  const duration =
+    Number.parseFloat(
+      element.dataAttributes.duration ?? element.dataAttributes["hf-authored-duration"] ?? "0",
+    ) || 0;
+  const end = start + duration;
+
+  const commitStart = (nextValue: string) => {
+    const parsed = parseTimingValue(nextValue);
+    if (parsed == null) return;
+    void onSetAttribute("start", parsed.toFixed(2));
+  };
+
+  const commitDuration = (nextValue: string) => {
+    const parsed = parseTimingValue(nextValue);
+    if (parsed == null || parsed <= 0) return;
+    void onSetAttribute("duration", parsed.toFixed(2));
+  };
+
+  const commitEnd = (nextValue: string) => {
+    const parsed = parseTimingValue(nextValue);
+    if (parsed == null || parsed <= start) return;
+    void onSetAttribute("duration", (parsed - start).toFixed(2));
+  };
+
+  return (
+    <Section title="Timing" icon={<Clock size={15} />}>
+      <div className={RESPONSIVE_GRID}>
+        <MetricField label="Start" value={formatTimingValue(start)} onCommit={commitStart} />
+        <MetricField label="End" value={formatTimingValue(end)} onCommit={commitEnd} />
+      </div>
+      <div className="mt-3">
+        <MetricField
+          label="Duration"
+          value={formatTimingValue(duration)}
+          onCommit={commitDuration}
+        />
+      </div>
+    </Section>
+  );
+}
@@ -30,6 +30,7 @@ import {
  tryGsapRotationIntercept,
 } from "./gsapRuntimeBridge";
 import { useAnimatedPropertyCommit } from "./useAnimatedPropertyCommit";
+import { useGsapSelectionHandlers } from "./useGsapSelectionHandlers";

 // ── Types ──

@@ -308,10 +309,7 @@ export function useDomEditSession({
    buildDomSelectionFromTarget,
  });

-  // Wrap the CSS-based path offset commit with GSAP-awareness: when the
-  // selected element has GSAP animations controlling x/y, read the actual
-  // interpolated position from the iframe runtime and commit via the GSAP
-  // script mutation path instead of the CSS translate offset.
+  // GSAP-aware: intercept offset/resize/rotation to commit via script mutation when animated.
  const handleGsapAwarePathOffsetCommit = useCallback(
    async (selection: DomEditSelection, next: { x: number; y: number }) => {
      if (gsapCommitMutation) {
@@ -406,126 +404,40 @@ export function useDomEditSession({
    ],
  );

-  const handleGsapUpdateProperty = useCallback(
-    (animId: string, prop: string, value: number | string) => {
-      if (!domEditSelection) return;
-      updateGsapProperty(domEditSelection, animId, prop, value);
-    },
-    [domEditSelection, updateGsapProperty],
-  );
-
-  const handleGsapUpdateMeta = useCallback(
-    (animId: string, updates: { duration?: number; ease?: string; position?: number }) => {
-      if (!domEditSelection) return;
-      updateGsapMeta(domEditSelection, animId, updates);
-    },
-    [domEditSelection, updateGsapMeta],
-  );
-
-  const handleGsapDeleteAnimation = useCallback(
-    (animId: string) => {
-      if (!domEditSelection) return;
-      deleteGsapAnimation(domEditSelection, animId);
-    },
-    [domEditSelection, deleteGsapAnimation],
-  );
-
-  const handleGsapAddAnimation = useCallback(
-    (method: "to" | "from" | "set" | "fromTo") => {
-      if (!domEditSelection) return;
-      addGsapAnimation(domEditSelection, method, currentTime);
-      if (domEditSelection.element.hasAttribute("data-hf-studio-path-offset")) {
-        handleDomManualEditsReset(domEditSelection);
-      }
-    },
-    [domEditSelection, addGsapAnimation, currentTime, handleDomManualEditsReset],
-  );
-
-  const handleGsapAddProperty = useCallback(
-    (animId: string, prop: string) => {
-      if (!domEditSelection) return;
-      addGsapProperty(domEditSelection, animId, prop);
-    },
-    [domEditSelection, addGsapProperty],
-  );
-
-  const handleGsapRemoveProperty = useCallback(
-    (animId: string, prop: string) => {
-      if (!domEditSelection) return;
-      removeGsapProperty(domEditSelection, animId, prop);
-    },
-    [domEditSelection, removeGsapProperty],
-  );
-
-  const handleGsapUpdateFromProperty = useCallback(
-    (animId: string, prop: string, value: number | string) => {
-      if (!domEditSelection) return;
-      updateGsapFromProperty(domEditSelection, animId, prop, value);
-    },
-    [domEditSelection, updateGsapFromProperty],
-  );
-
-  const handleGsapAddFromProperty = useCallback(
-    (animId: string, prop: string) => {
-      if (!domEditSelection) return;
-      addGsapFromProperty(domEditSelection, animId, prop);
-    },
-    [domEditSelection, addGsapFromProperty],
-  );
-
-  const handleGsapRemoveFromProperty = useCallback(
-    (animId: string, prop: string) => {
-      if (!domEditSelection) return;
-      removeGsapFromProperty(domEditSelection, animId, prop);
-    },
-    [domEditSelection, removeGsapFromProperty],
-  );
-
-  const handleGsapAddKeyframe = useCallback(
-    (animId: string, percentage: number, property: string, value: number | string) => {
-      if (!domEditSelection) return;
-      addKeyframe(domEditSelection, animId, percentage, property, value);
-    },
-    [domEditSelection, addKeyframe],
-  );
-
-  const handleGsapRemoveKeyframe = useCallback(
-    (animId: string, percentage: number) => {
-      if (!domEditSelection) return;
-      removeKeyframe(domEditSelection, animId, percentage);
-    },
-    [domEditSelection, removeKeyframe],
-  );
-
-  const handleGsapConvertToKeyframes = useCallback(
-    (animId: string) => {
-      if (!domEditSelection) return;
-      convertToKeyframes(domEditSelection, animId);
-    },
-    [domEditSelection, convertToKeyframes],
-  );
-
-  const handleGsapRemoveAllKeyframes = useCallback(
-    (animId: string) => {
-      if (!domEditSelection) return;
-      removeAllKeyframes(domEditSelection, animId);
-    },
-    [domEditSelection, removeAllKeyframes],
-  );
-
-  /**
-   * Reset keyframes for the currently selected element.
-   * Finds the animation with keyframes from the resolved GSAP animations
-   * and sends a remove-all-keyframes mutation. Returns true if keyframes
-   * were found and the mutation was dispatched.
-   */
-  const handleResetSelectedElementKeyframes = useCallback((): boolean => {
-    if (!domEditSelection) return false;
-    const withKeyframes = selectedGsapAnimations.find((a) => a.keyframes);
-    if (!withKeyframes) return false;
-    removeAllKeyframes(domEditSelection, withKeyframes.id);
-    return true;
-  }, [domEditSelection, selectedGsapAnimations, removeAllKeyframes]);
+  const {
+    handleGsapUpdateProperty,
+    handleGsapUpdateMeta,
+    handleGsapDeleteAnimation,
+    handleGsapAddAnimation,
+    handleGsapAddProperty,
+    handleGsapRemoveProperty,
+    handleGsapUpdateFromProperty,
+    handleGsapAddFromProperty,
+    handleGsapRemoveFromProperty,
+    handleGsapAddKeyframe,
+    handleGsapRemoveKeyframe,
+    handleGsapConvertToKeyframes,
+    handleGsapRemoveAllKeyframes,
+    handleResetSelectedElementKeyframes,
+  } = useGsapSelectionHandlers({
+    domEditSelection,
+    updateGsapProperty,
+    updateGsapMeta,
+    deleteGsapAnimation,
+    addGsapAnimation,
+    addGsapProperty,
+    removeGsapProperty,
+    updateGsapFromProperty,
+    addGsapFromProperty,
+    removeGsapFromProperty,
+    addKeyframe,
+    removeKeyframe,
+    convertToKeyframes,
+    removeAllKeyframes,
+    currentTime,
+    handleDomManualEditsReset,
+    selectedGsapAnimations,
+  });

  const commitAnimatedProperty = useAnimatedPropertyCommit({
    selectedGsapAnimations,
@@ -0,0 +1,202 @@
+import { useCallback } from "react";
+import type { DomEditSelection } from "../components/editor/domEditing";
+
+/**
+ * Thin useCallback wrappers that guard on `domEditSelection` before
+ * delegating to the underlying GSAP script-commit functions. Extracted
+ * from useDomEditSession to keep that file under the 600-line limit.
+ */
+// fallow-ignore-next-line complexity
+export function useGsapSelectionHandlers({
+  domEditSelection,
+  updateGsapProperty,
+  updateGsapMeta,
+  deleteGsapAnimation,
+  addGsapAnimation,
+  addGsapProperty,
+  removeGsapProperty,
+  updateGsapFromProperty,
+  addGsapFromProperty,
+  removeGsapFromProperty,
+  addKeyframe,
+  removeKeyframe,
+  convertToKeyframes,
+  removeAllKeyframes,
+  currentTime,
+  handleDomManualEditsReset,
+  selectedGsapAnimations,
+}: {
+  domEditSelection: DomEditSelection | null;
+  updateGsapProperty: (
+    sel: DomEditSelection,
+    animId: string,
+    prop: string,
+    value: number | string,
+  ) => void;
+  updateGsapMeta: (
+    sel: DomEditSelection,
+    animId: string,
+    updates: { duration?: number; ease?: string; position?: number },
+  ) => void;
+  deleteGsapAnimation: (sel: DomEditSelection, animId: string) => void;
+  addGsapAnimation: (
+    sel: DomEditSelection,
+    method: "to" | "from" | "set" | "fromTo",
+    time: number,
+  ) => void;
+  addGsapProperty: (sel: DomEditSelection, animId: string, prop: string) => void;
+  removeGsapProperty: (sel: DomEditSelection, animId: string, prop: string) => void;
+  updateGsapFromProperty: (
+    sel: DomEditSelection,
+    animId: string,
+    prop: string,
+    value: number | string,
+  ) => void;
+  addGsapFromProperty: (sel: DomEditSelection, animId: string, prop: string) => void;
+  removeGsapFromProperty: (sel: DomEditSelection, animId: string, prop: string) => void;
+  addKeyframe: (
+    sel: DomEditSelection,
+    animId: string,
+    percentage: number,
+    property: string,
+    value: number | string,
+  ) => void;
+  removeKeyframe: (sel: DomEditSelection, animId: string, percentage: number) => void;
+  convertToKeyframes: (sel: DomEditSelection, animId: string) => void;
+  removeAllKeyframes: (sel: DomEditSelection, animId: string) => void;
+  currentTime: number;
+  handleDomManualEditsReset: (sel: DomEditSelection) => void;
+  selectedGsapAnimations: { id: string; keyframes?: unknown }[];
+}) {
+  const handleGsapUpdateProperty = useCallback(
+    (animId: string, prop: string, value: number | string) => {
+      if (!domEditSelection) return;
+      updateGsapProperty(domEditSelection, animId, prop, value);
+    },
+    [domEditSelection, updateGsapProperty],
+  );
+
+  const handleGsapUpdateMeta = useCallback(
+    (animId: string, updates: { duration?: number; ease?: string; position?: number }) => {
+      if (!domEditSelection) return;
+      updateGsapMeta(domEditSelection, animId, updates);
+    },
+    [domEditSelection, updateGsapMeta],
+  );
+
+  const handleGsapDeleteAnimation = useCallback(
+    (animId: string) => {
+      if (!domEditSelection) return;
+      deleteGsapAnimation(domEditSelection, animId);
+    },
+    [domEditSelection, deleteGsapAnimation],
+  );
+
+  const handleGsapAddAnimation = useCallback(
+    (method: "to" | "from" | "set" | "fromTo") => {
+      if (!domEditSelection) return;
+      addGsapAnimation(domEditSelection, method, currentTime);
+      if (domEditSelection.element.hasAttribute("data-hf-studio-path-offset")) {
+        handleDomManualEditsReset(domEditSelection);
+      }
+    },
+    [domEditSelection, addGsapAnimation, currentTime, handleDomManualEditsReset],
+  );
+
+  const handleGsapAddProperty = useCallback(
+    (animId: string, prop: string) => {
+      if (!domEditSelection) return;
+      addGsapProperty(domEditSelection, animId, prop);
+    },
+    [domEditSelection, addGsapProperty],
+  );
+
+  const handleGsapRemoveProperty = useCallback(
+    (animId: string, prop: string) => {
+      if (!domEditSelection) return;
+      removeGsapProperty(domEditSelection, animId, prop);
+    },
+    [domEditSelection, removeGsapProperty],
+  );
+
+  const handleGsapUpdateFromProperty = useCallback(
+    (animId: string, prop: string, value: number | string) => {
+      if (!domEditSelection) return;
+      updateGsapFromProperty(domEditSelection, animId, prop, value);
+    },
+    [domEditSelection, updateGsapFromProperty],
+  );
+
+  const handleGsapAddFromProperty = useCallback(
+    (animId: string, prop: string) => {
+      if (!domEditSelection) return;
+      addGsapFromProperty(domEditSelection, animId, prop);
+    },
+    [domEditSelection, addGsapFromProperty],
+  );
+
+  const handleGsapRemoveFromProperty = useCallback(
+    (animId: string, prop: string) => {
+      if (!domEditSelection) return;
+      removeGsapFromProperty(domEditSelection, animId, prop);
+    },
+    [domEditSelection, removeGsapFromProperty],
+  );
+
+  const handleGsapAddKeyframe = useCallback(
+    (animId: string, percentage: number, property: string, value: number | string) => {
+      if (!domEditSelection) return;
+      addKeyframe(domEditSelection, animId, percentage, property, value);
+    },
+    [domEditSelection, addKeyframe],
+  );
+
+  const handleGsapRemoveKeyframe = useCallback(
+    (animId: string, percentage: number) => {
+      if (!domEditSelection) return;
+      removeKeyframe(domEditSelection, animId, percentage);
+    },
+    [domEditSelection, removeKeyframe],
+  );
+
+  const handleGsapConvertToKeyframes = useCallback(
+    (animId: string) => {
+      if (!domEditSelection) return;
+      convertToKeyframes(domEditSelection, animId);
+    },
+    [domEditSelection, convertToKeyframes],
+  );
+
+  const handleGsapRemoveAllKeyframes = useCallback(
+    (animId: string) => {
+      if (!domEditSelection) return;
+      removeAllKeyframes(domEditSelection, animId);
+    },
+    [domEditSelection, removeAllKeyframes],
+  );
+
+  const handleResetSelectedElementKeyframes = useCallback((): boolean => {
+    if (!domEditSelection) return false;
+    const withKeyframes = selectedGsapAnimations.find((a) => a.keyframes);
+    if (!withKeyframes) return false;
+    removeAllKeyframes(domEditSelection, withKeyframes.id);
+    return true;
+  }, [domEditSelection, selectedGsapAnimations, removeAllKeyframes]);
+
+  return {
+    handleGsapUpdateProperty,
+    handleGsapUpdateMeta,
+    handleGsapDeleteAnimation,
+    handleGsapAddAnimation,
+    handleGsapAddProperty,
+    handleGsapRemoveProperty,
+    handleGsapUpdateFromProperty,
+    handleGsapAddFromProperty,
+    handleGsapRemoveFromProperty,
+    handleGsapAddKeyframe,
+    handleGsapRemoveKeyframe,
+    handleGsapConvertToKeyframes,
+    handleGsapRemoveAllKeyframes,
+    handleResetSelectedElementKeyframes,
+  };
+}
@@ -12,6 +12,7 @@ import {
  shouldHandleTimelineDeleteKey,
  shouldAutoScrollTimeline,
 } from "./Timeline";
+import { RULER_H, TRACK_H } from "./timelineLayout";
 import { formatTime } from "../lib/time";

 describe("generateTicks", () => {
@@ -230,8 +231,7 @@ describe("getTimelinePlayheadLeft", () => {

 describe("getTimelineCanvasHeight", () => {
  it("includes bottom scroll buffer below the last track", () => {
-    // RULER_H (24) + trackCount * TRACK_H (48) + scroll buffer
-    expect(getTimelineCanvasHeight(3)).toBeGreaterThan(24 + 3 * 48);
+    expect(getTimelineCanvasHeight(3)).toBeGreaterThan(RULER_H + 3 * TRACK_H);
  });

  it("still keeps ruler space when there are no tracks", () => {
@@ -8,7 +8,7 @@ import { useTimelineRangeSelection } from "./useTimelineRangeSelection";
 import { useTimelinePlayhead } from "./useTimelinePlayhead";
 import { type TrackVisualStyle, getTrackStyle } from "./timelineIcons";
 import { getTimelinePixelsPerSecond } from "./timelineZoom";
-import { TIMELINE_ASSET_MIME, TIMELINE_BLOCK_MIME } from "../../utils/timelineAssetDrop";
+import { useTimelineAssetDrop } from "./timelineDragDrop";
 import { TimelineEmptyState } from "./TimelineEmptyState";
 import { TimelineCanvas } from "./TimelineCanvas";
 import {
@@ -19,11 +19,9 @@ import { useTimelineClipDrag } from "./useTimelineClipDrag";
 import { ClipContextMenu } from "./ClipContextMenu";
 import {
  GUTTER,
-  TRACK_H,
  generateTicks,
  getTimelineCanvasHeight,
  shouldShowTimelineShortcutHint,
-  resolveTimelineAssetDrop,
 } from "./timelineLayout";

 // Re-export pure utilities so existing imports from "./Timeline" still resolve.
@@ -364,71 +362,15 @@ export const Timeline = memo(function Timeline({
    [resizingClip],
  );

-  const [isDragOver, setIsDragOver] = useState(false);
-  const handleAssetDragOver = useCallback((e: React.DragEvent) => {
-    const hasFiles = e.dataTransfer.files.length > 0;
-    const types = Array.from(e.dataTransfer.types);
-    const hasAsset = types.includes(TIMELINE_ASSET_MIME);
-    const hasBlock = types.includes(TIMELINE_BLOCK_MIME);
-    if (!hasFiles && !hasAsset && !hasBlock) return;
-    e.preventDefault();
-    if (hasAsset || hasBlock) e.dataTransfer.dropEffect = "copy";
-    setIsDragOver(true);
-  }, []);
-
-  const handleAssetDrop = useCallback(
-    (e: React.DragEvent) => {
-      e.preventDefault();
-      setIsDragOver(false);
-      const scroll = scrollRef.current;
-      const rect = scroll?.getBoundingClientRect();
-      const dropInput = {
-        rectLeft: rect?.left ?? 0,
-        rectTop: rect?.top ?? 0,
-        scrollLeft: scroll?.scrollLeft ?? 0,
-        scrollTop: scroll?.scrollTop ?? 0,
-        pixelsPerSecond: ppsRef.current,
-        duration: durationRef.current,
-        trackHeight: TRACK_H,
-        trackOrder: trackOrderRef.current,
-      };
-      if (onFileDrop && e.dataTransfer.files.length > 0) {
-        void onFileDrop(
-          Array.from(e.dataTransfer.files),
-          scroll && rect ? resolveTimelineAssetDrop(dropInput, e.clientX, e.clientY) : undefined,
-        );
-        return;
-      }
-      const assetPayload = e.dataTransfer.getData(TIMELINE_ASSET_MIME);
-      if (assetPayload && onAssetDrop && scroll && rect) {
-        try {
-          const parsed = JSON.parse(assetPayload) as { path?: string };
-          if (parsed.path)
-            void onAssetDrop(
-              parsed.path,
-              resolveTimelineAssetDrop(dropInput, e.clientX, e.clientY),
-            );
-        } catch {
-          /* ignore malformed drag payloads */
-        }
-        return;
-      }
-      const blockPayload = e.dataTransfer.getData(TIMELINE_BLOCK_MIME);
-      if (blockPayload && onBlockDrop && scroll && rect) {
-        try {
-          const parsed = JSON.parse(blockPayload) as { name?: string };
-          if (parsed.name)
-            void onBlockDrop(
-              parsed.name,
-              resolveTimelineAssetDrop(dropInput, e.clientX, e.clientY),
-            );
-        } catch {
-          /* ignore malformed drag payloads */
-        }
-      }
-    },
-    [onAssetDrop, onBlockDrop, onFileDrop],
-  );
+  const { isDragOver, setIsDragOver, handleAssetDragOver, handleAssetDrop } = useTimelineAssetDrop({
+    scrollRef,
+    ppsRef,
+    durationRef,
+    trackOrderRef,
+    onFileDrop,
+    onAssetDrop,
+    onBlockDrop,
+  });

  if (!timelineReady || elements.length === 0) {
    return (
@@ -0,0 +1,103 @@
+// fallow-ignore-file clone-families
+import { useCallback, useState, type RefObject } from "react";
+import { TIMELINE_ASSET_MIME, TIMELINE_BLOCK_MIME } from "../../utils/timelineAssetDrop";
+import { TRACK_H, resolveTimelineAssetDrop } from "./timelineLayout";
+
+interface UseTimelineAssetDropOptions {
+  scrollRef: RefObject<HTMLDivElement | null>;
+  ppsRef: RefObject<number>;
+  durationRef: RefObject<number>;
+  trackOrderRef: RefObject<number[]>;
+  onFileDrop?: (
+    files: File[],
+    placement?: { start: number; track: number },
+  ) => Promise<void> | void;
+  onAssetDrop?: (
+    assetPath: string,
+    placement: { start: number; track: number },
+  ) => Promise<void> | void;
+  onBlockDrop?: (
+    blockName: string,
+    placement: { start: number; track: number },
+  ) => Promise<void> | void;
+}
+
+export function useTimelineAssetDrop({
+  scrollRef,
+  ppsRef,
+  durationRef,
+  trackOrderRef,
+  onFileDrop,
+  onAssetDrop,
+  onBlockDrop,
+}: UseTimelineAssetDropOptions) {
+  const [isDragOver, setIsDragOver] = useState(false);
+
+  const handleAssetDragOver = useCallback((e: React.DragEvent) => {
+    const hasFiles = e.dataTransfer.files.length > 0;
+    const types = Array.from(e.dataTransfer.types);
+    const hasAsset = types.includes(TIMELINE_ASSET_MIME);
+    const hasBlock = types.includes(TIMELINE_BLOCK_MIME);
+    if (!hasFiles && !hasAsset && !hasBlock) return;
+    e.preventDefault();
+    if (hasAsset || hasBlock) e.dataTransfer.dropEffect = "copy";
+    setIsDragOver(true);
+  }, []);
+
+  const handleAssetDrop = useCallback(
+    // fallow-ignore-next-line complexity
+    (e: React.DragEvent) => {
+      e.preventDefault();
+      setIsDragOver(false);
+      const scroll = scrollRef.current;
+      const rect = scroll?.getBoundingClientRect();
+      const dropInput = {
+        rectLeft: rect?.left ?? 0,
+        rectTop: rect?.top ?? 0,
+        scrollLeft: scroll?.scrollLeft ?? 0,
+        scrollTop: scroll?.scrollTop ?? 0,
+        pixelsPerSecond: ppsRef.current,
+        duration: durationRef.current,
+        trackHeight: TRACK_H,
+        trackOrder: trackOrderRef.current,
+      };
+      if (onFileDrop && e.dataTransfer.files.length > 0) {
+        void onFileDrop(
+          Array.from(e.dataTransfer.files),
+          scroll && rect ? resolveTimelineAssetDrop(dropInput, e.clientX, e.clientY) : undefined,
+        );
+        return;
+      }
+      const assetPayload = e.dataTransfer.getData(TIMELINE_ASSET_MIME);
+      if (assetPayload && onAssetDrop && scroll && rect) {
+        try {
+          const parsed = JSON.parse(assetPayload) as { path?: string };
+          if (parsed.path)
+            void onAssetDrop(
+              parsed.path,
+              resolveTimelineAssetDrop(dropInput, e.clientX, e.clientY),
+            );
+        } catch {
+          /* ignore malformed drag payloads */
+        }
+        return;
+      }
+      const blockPayload = e.dataTransfer.getData(TIMELINE_BLOCK_MIME);
+      if (blockPayload && onBlockDrop && scroll && rect) {
+        try {
+          const parsed = JSON.parse(blockPayload) as { name?: string };
+          if (parsed.name)
+            void onBlockDrop(
+              parsed.name,
+              resolveTimelineAssetDrop(dropInput, e.clientX, e.clientY),
+            );
+        } catch {
+          /* ignore malformed drag payloads */
+        }
+      }
+    },
+    [onAssetDrop, onBlockDrop, onFileDrop, scrollRef, ppsRef, durationRef, trackOrderRef],
+  );
+
+  return { isDragOver, setIsDragOver, handleAssetDragOver, handleAssetDrop };
+}