refactor: extract timeline model types

Move project entity shapes into the model layer so sibling domains no longer depend on timeline for core data types.

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/web/src/clipboard/handlers/keyframes.ts

@@ -1,6 +1,6 @@
 import { getKeyframeById } from "@/animation";
 import type { SelectedKeyframeRef } from "@/animation/types";
-import type { TimelineElement } from "@/timeline";
+import { elementId, type ElementRef, type TimelineElement } from "@/model";
 import { PasteKeyframesCommand } from "@/commands/timeline";
 import type {
 	ClipboardHandler,
@@ -12,7 +12,7 @@ function resolveSingleSourceElement({
 	selectedKeyframes,
 }: {
 	selectedKeyframes: SelectedKeyframeRef[];
-}) {
+}): ElementRef | null {
 	const firstKeyframe = selectedKeyframes[0];
 	if (!firstKeyframe) {
 		return null;
@@ -20,7 +20,7 @@ function resolveSingleSourceElement({
 
 	const sourceElement = {
 		trackId: firstKeyframe.trackId,
-		elementId: firstKeyframe.elementId,
+		elementId: elementId(firstKeyframe.elementId),
 	};
 	const isSingleSource = selectedKeyframes.every(
 		(keyframe) =>

apps/web/src/clipboard/types.ts

@@ -7,11 +7,7 @@ import type {
 	SelectedKeyframeRef,
 } from "@/animation/types";
 import type { Command } from "@/commands/base-command";
-import type {
+import type { CreateTimelineElement, ElementRef, TrackType } from "@/model";
-	CreateTimelineElement,
-	ElementRef,
-	TrackType,
-} from "@/timeline";
 
 export interface ElementClipboardItem {
 	trackId: string;

apps/web/src/commands/base-command.ts

@@ -1,5 +1,5 @@
 import type { EditorSelectionPatch } from "@/selection/editor-selection";
-import type { ElementRef } from "@/timeline/types";
+import type { ElementRef } from "@/model";
 
 export interface CommandResult {
 	selection?: EditorSelectionPatch;

apps/web/src/commands/media/remove-media-asset.ts

@@ -6,7 +6,7 @@ import { storageService } from "@/services/storage/service";
 import { videoCache } from "@/services/video-cache/service";
 import { waveformCache } from "@/services/waveform-cache/service";
 import { hasMediaId } from "@/timeline/element-utils";
-import type { SceneTracks } from "@/timeline";
+import type { SceneTracks } from "@/model";
 
 export class RemoveMediaAssetCommand extends Command {
 	private savedAssets: MediaAsset[] | null = null;

apps/web/src/commands/scene/create-scene.ts

@@ -1,6 +1,6 @@
 import { Command, type CommandResult } from "@/commands/base-command";
 import { EditorCore } from "@/core";
-import type { TScene } from "@/timeline";
+import type { TScene } from "@/model";
 import { buildDefaultScene } from "@/timeline/scenes";
 
 export class CreateSceneCommand extends Command {

apps/web/src/commands/scene/delete-scene.ts

@@ -1,6 +1,6 @@
 import { Command, type CommandResult } from "@/commands/base-command";
 import { EditorCore } from "@/core";
-import type { TScene } from "@/timeline";
+import type { TScene } from "@/model";
 import { canDeleteScene, getFallbackSceneAfterDelete } from "@/timeline/scenes";
 
 export class DeleteSceneCommand extends Command {

apps/web/src/commands/scene/move-bookmark.ts

@@ -1,6 +1,6 @@
 import { Command, type CommandResult } from "@/commands/base-command";
 import { EditorCore } from "@/core";
-import type { TScene } from "@/timeline";
+import type { TScene } from "@/model";
 import { updateSceneInArray } from "@/timeline/scenes";
 import { getFrameTime, moveBookmarkInArray } from "@/timeline/bookmarks/index";
 

apps/web/src/commands/scene/remove-bookmark.ts

@@ -1,6 +1,6 @@
 import { Command, type CommandResult } from "@/commands/base-command";
 import { EditorCore } from "@/core";
-import type { TScene } from "@/timeline";
+import type { TScene } from "@/model";
 import { updateSceneInArray } from "@/timeline/scenes";
 import {
 	getFrameTime,

apps/web/src/commands/scene/rename-scene.ts

@@ -1,6 +1,6 @@
 import { Command, type CommandResult } from "@/commands/base-command";
 import { EditorCore } from "@/core";
-import type { TScene } from "@/timeline";
+import type { TScene } from "@/model";
 import { updateSceneInArray } from "@/timeline/scenes";
 
 export class RenameSceneCommand extends Command {

apps/web/src/commands/scene/toggle-bookmark.ts

@@ -1,6 +1,6 @@
 import { Command, type CommandResult } from "@/commands/base-command";
 import { EditorCore } from "@/core";
-import type { TScene } from "@/timeline";
+import type { TScene } from "@/model";
 import { updateSceneInArray } from "@/timeline/scenes";
 import {
 	getFrameTime,

apps/web/src/commands/scene/update-bookmark.ts

@@ -1,6 +1,6 @@
 import { Command, type CommandResult } from "@/commands/base-command";
 import { EditorCore } from "@/core";
-import type { Bookmark, TScene } from "@/timeline";
+import type { Bookmark, TScene } from "@/model";
 import { updateSceneInArray } from "@/timeline/scenes";
 import {
 	getFrameTime,

apps/web/src/commands/timeline/clipboard/paste-keyframes.ts

@@ -6,7 +6,7 @@ import {
 } from "@/animation";
 import { Command, type CommandResult } from "@/commands/base-command";
 import type { KeyframeClipboardItem } from "@/clipboard";
-import type { SceneTracks, TimelineElement } from "@/timeline";
+import type { SceneTracks, TimelineElement } from "@/model";
 import { updateElementInSceneTracks } from "@/timeline";
 import { resolveAnimationTarget } from "@/timeline/animation-targets";
 import { generateUUID } from "@/utils/id";

apps/web/src/commands/timeline/clipboard/paste.ts

@@ -4,7 +4,7 @@ import {
 	type CommandResult,
 } from "@/commands/base-command";
 import { EditorCore } from "@/core";
-import type { SceneTracks, TimelineElement } from "@/timeline";
+import type { ElementRef, SceneTracks, TimelineElement } from "@/model";
 import type { ElementClipboardItem } from "@/clipboard";
 import { generateUUID } from "@/utils/id";
 import {
@@ -16,7 +16,7 @@ import { cloneAnimations } from "@/animation";
 
 export class PasteCommand extends Command {
 	private savedState: SceneTracks | null = null;
-	private pastedElements: { trackId: string; elementId: string }[] = [];
+	private pastedElements: ElementRef[] = [];
 	private readonly time: number;
 	private readonly clipboardItems: ElementClipboardItem[];
 
@@ -142,7 +142,7 @@ export class PasteCommand extends Command {
 		}
 	}
 
-	getPastedElements(): { trackId: string; elementId: string }[] {
+	getPastedElements(): ElementRef[] {
 		return this.pastedElements;
 	}
 }

apps/web/src/commands/timeline/element/delete-elements.ts

@@ -1,7 +1,7 @@
 import { Command, type CommandResult } from "@/commands/base-command";
-import type { SceneTracks } from "@/timeline";
+import type { SceneTracks } from "@/model";
 import { EditorCore } from "@/core";
-import type { TimelineTrack } from "@/timeline";
+import type { TimelineTrack } from "@/model";
 
 function removeTrackElements<TTrack extends TimelineTrack>({
 	track,

apps/web/src/commands/timeline/element/duplicate-elements.ts

@@ -3,7 +3,13 @@ import {
 	createElementSelectionResult,
 	type CommandResult,
 } from "@/commands/base-command";
-import type { SceneTracks, TimelineElement } from "@/timeline";
+import {
+	elementId,
+	type ElementId,
+	type ElementRef,
+	type SceneTracks,
+	type TimelineElement,
+} from "@/model";
 import { generateUUID } from "@/utils/id";
 import { EditorCore } from "@/core";
 import { applyPlacement, resolveTrackPlacement } from "@/timeline/placement";
@@ -14,7 +20,7 @@ interface DuplicateElementsParams {
 }
 
 export class DuplicateElementsCommand extends Command {
-	private duplicatedElements: { trackId: string; elementId: string }[] = [];
+	private duplicatedElements: ElementRef[] = [];
 	private savedState: SceneTracks | null = null;
 	private elements: DuplicateElementsParams["elements"];
 
@@ -53,7 +59,7 @@ export class DuplicateElementsCommand extends Command {
 					continue;
 				}
 
-				const newId = generateUUID();
+				const newId = elementId(generateUUID());
 				newTrackElements.push(
 					buildDuplicateElement({
 						element,
@@ -107,7 +113,7 @@ export class DuplicateElementsCommand extends Command {
 		}
 	}
 
-	getDuplicatedElements(): { trackId: string; elementId: string }[] {
+	getDuplicatedElements(): ElementRef[] {
 		return this.duplicatedElements;
 	}
 }
@@ -118,7 +124,7 @@ function buildDuplicateElement({
 	startTime,
 }: {
 	element: TimelineElement;
-	id: string;
+	id: ElementId;
 	startTime: number;
 }): TimelineElement {
 	return {

apps/web/src/commands/timeline/element/effects/add-effect.ts

@@ -1,7 +1,7 @@
 import { Command, type CommandResult } from "@/commands/base-command";
 import { EditorCore } from "@/core";
 import { isVisualElement, updateElementInSceneTracks } from "@/timeline";
-import type { SceneTracks, VisualElement } from "@/timeline";
+import type { SceneTracks, VisualElement } from "@/model";
 import { buildDefaultEffectInstance } from "@/effects";
 
 function addEffectToElement({

apps/web/src/commands/timeline/element/effects/remove-effect.ts

@@ -1,7 +1,7 @@
 import { Command, type CommandResult } from "@/commands/base-command";
 import { EditorCore } from "@/core";
 import { isVisualElement, updateElementInSceneTracks } from "@/timeline";
-import type { SceneTracks, VisualElement } from "@/timeline";
+import type { SceneTracks, VisualElement } from "@/model";
 
 function removeEffectFromElement({
 	element,

apps/web/src/commands/timeline/element/effects/reorder-effect.ts

@@ -1,7 +1,7 @@
 import { Command, type CommandResult } from "@/commands/base-command";
 import { EditorCore } from "@/core";
 import { isVisualElement, updateElementInSceneTracks } from "@/timeline";
-import type { SceneTracks, VisualElement } from "@/timeline";
+import type { SceneTracks, VisualElement } from "@/model";
 
 function reorderEffectsOnElement({
 	element,

apps/web/src/commands/timeline/element/effects/toggle-effect.ts

@@ -1,7 +1,7 @@
 import { Command, type CommandResult } from "@/commands/base-command";
 import { EditorCore } from "@/core";
 import { isVisualElement, updateElementInSceneTracks } from "@/timeline";
-import type { SceneTracks, VisualElement } from "@/timeline";
+import type { SceneTracks, VisualElement } from "@/model";
 
 export function toggleEffectOnElement({
 	element,

apps/web/src/commands/timeline/element/effects/update-effect-params.ts

@@ -2,7 +2,7 @@ import { Command, type CommandResult } from "@/commands/base-command";
 import { EditorCore } from "@/core";
 import { isVisualElement, updateElementInSceneTracks } from "@/timeline";
 import type { ParamValues } from "@/params";
-import type { SceneTracks, VisualElement } from "@/timeline";
+import type { SceneTracks, VisualElement } from "@/model";
 
 function updateEffectParamsOnElement({
 	element,

apps/web/src/commands/timeline/element/insert-element.ts

@@ -1,11 +1,13 @@
 import { Command, type CommandResult } from "@/commands/base-command";
 import { EditorCore } from "@/core";
-import type {
+import {
-	CreateTimelineElement,
+	elementId,
-	SceneTracks,
+	type CreateTimelineElement,
-	TimelineElement,
+	type ElementId,
-	TrackType,
+	type SceneTracks,
-} from "@/timeline";
+	type TimelineElement,
+	type TrackType,
+} from "@/model";
 import { generateUUID } from "@/utils/id";
 import { requiresMediaId } from "@/timeline/element-utils";
 import type { MediaAsset } from "@/media/types";
@@ -29,13 +31,13 @@ export interface InsertElementParams {
 }
 
 export class InsertElementCommand extends Command {
-	private elementId: string;
+	private elementId: ElementId;
 	private savedState: SceneTracks | null = null;
 	private targetTrackId: string | null = null;
 
 	constructor({ element, placement }: InsertElementParams) {
 		super();
-		this.elementId = generateUUID();
+		this.elementId = elementId(generateUUID());
 		this.element = element;
 		this.placement = placement;
 	}

apps/web/src/commands/timeline/element/keyframes/remove-effect-param-keyframe.ts

@@ -3,7 +3,7 @@ import { Command, type CommandResult } from "@/commands/base-command";
 import { removeEffectParamKeyframe } from "@/animation/effect-param-channel";
 import { updateElementInSceneTracks } from "@/timeline";
 import { isVisualElement } from "@/timeline/element-utils";
-import type { SceneTracks } from "@/timeline";
+import type { SceneTracks } from "@/model";
 
 export class RemoveEffectParamKeyframeCommand extends Command {
 	private savedState: SceneTracks | null = null;

apps/web/src/commands/timeline/element/keyframes/remove-keyframe.ts

@@ -6,7 +6,7 @@ import {
 import { Command, type CommandResult } from "@/commands/base-command";
 import { updateElementInSceneTracks } from "@/timeline";
 import type { AnimationPath, AnimationValue } from "@/animation/types";
-import type { SceneTracks, TimelineElement } from "@/timeline";
+import type { SceneTracks, TimelineElement } from "@/model";
 import { resolveAnimationTarget } from "@/timeline/animation-targets";
 
 function removeKeyframeAndPersist({

apps/web/src/commands/timeline/element/keyframes/retime-keyframe.ts

@@ -3,7 +3,7 @@ import { retimeElementKeyframe } from "@/animation";
 import { Command, type CommandResult } from "@/commands/base-command";
 import { updateElementInSceneTracks } from "@/timeline";
 import type { AnimationPath } from "@/animation/types";
-import type { SceneTracks } from "@/timeline";
+import type { SceneTracks } from "@/model";
 import { resolveAnimationTarget } from "@/timeline/animation-targets";
 
 export class RetimeKeyframeCommand extends Command {

apps/web/src/commands/timeline/element/keyframes/update-scalar-keyframe-curve.ts

@@ -9,7 +9,7 @@ import type {
 	AnimationPath,
 	ScalarCurveKeyframePatch,
 } from "@/animation/types";
-import type { SceneTracks } from "@/timeline";
+import type { SceneTracks } from "@/model";
 
 export class UpdateScalarKeyframeCurveCommand extends Command {
 	private savedState: SceneTracks | null = null;

apps/web/src/commands/timeline/element/keyframes/upsert-effect-param-keyframe.ts

@@ -8,7 +8,7 @@ import { updateElementInSceneTracks } from "@/timeline";
 import { isVisualElement } from "@/timeline/element-utils";
 import { resolveAnimationTarget } from "@/timeline/animation-targets";
 import type { AnimationInterpolation } from "@/animation/types";
-import type { SceneTracks } from "@/timeline";
+import type { SceneTracks } from "@/model";
 
 export class UpsertEffectParamKeyframeCommand extends Command {
 	private savedState: SceneTracks | null = null;

apps/web/src/commands/timeline/element/keyframes/upsert-keyframe.ts

@@ -2,7 +2,7 @@ import { EditorCore } from "@/core";
 import { Command, type CommandResult } from "@/commands/base-command";
 import { upsertPathKeyframe } from "@/animation";
 import { updateElementInSceneTracks } from "@/timeline";
-import type { SceneTracks } from "@/timeline";
+import type { SceneTracks } from "@/model";
 import { resolveAnimationTarget } from "@/timeline/animation-targets";
 import type {
 	AnimationPath,

apps/web/src/commands/timeline/element/masks/delete-custom-mask-points.ts

@@ -6,7 +6,7 @@ import {
 } from "@/masks/custom-path";
 import type { CustomMask } from "@/masks/types";
 import { isMaskableElement, updateElementInSceneTracks } from "@/timeline";
-import type { MaskableElement, SceneTracks } from "@/timeline";
+import type { MaskableElement, SceneTracks } from "@/model";
 
 function deletePointsFromCustomMask({
 	mask,

apps/web/src/commands/timeline/element/masks/insert-custom-mask-point.ts

@@ -4,7 +4,7 @@ import { insertPointOnCustomMaskSegment } from "@/masks/definitions/custom";
 import type { ElementBounds } from "@/preview/element-bounds";
 import type { CustomMask } from "@/masks/types";
 import { isMaskableElement, updateElementInSceneTracks } from "@/timeline";
-import type { MaskableElement, SceneTracks } from "@/timeline";
+import type { MaskableElement, SceneTracks } from "@/model";
 
 function insertPointIntoCustomMask({
 	mask,

apps/web/src/commands/timeline/element/masks/remove-mask.ts

@@ -1,7 +1,7 @@
 import { EditorCore } from "@/core";
 import { Command, type CommandResult } from "@/commands/base-command";
 import { isMaskableElement, updateElementInSceneTracks } from "@/timeline";
-import type { SceneTracks, MaskableElement } from "@/timeline";
+import type { MaskableElement, SceneTracks } from "@/model";
 
 function removeMaskFromElement({
 	element,

apps/web/src/commands/timeline/element/masks/toggle-mask-inverted.ts

@@ -2,7 +2,7 @@ import { EditorCore } from "@/core";
 import { Command, type CommandResult } from "@/commands/base-command";
 import { isMaskableElement, updateElementInSceneTracks } from "@/timeline";
 import type { Mask } from "@/masks/types";
-import type { SceneTracks, MaskableElement } from "@/timeline";
+import type { MaskableElement, SceneTracks } from "@/model";
 
 export function toggleMaskInvertedOnElement({
 	element,

apps/web/src/commands/timeline/element/move-elements.ts

@@ -4,7 +4,12 @@ import {
 	type CommandResult,
 } from "@/commands/base-command";
 import { EditorCore } from "@/core";
-import type { SceneTracks, TimelineElement, TimelineTrack } from "@/timeline";
+import {
+	elementId as toElementId,
+	type SceneTracks,
+	type TimelineElement,
+	type TimelineTrack,
+} from "@/model";
 import {
 	buildEmptyTrack,
 	validateElementTrackCompatibility,
@@ -117,7 +122,7 @@ export class MoveElementCommand extends Command {
 		return createElementSelectionResult(
 			this.moves.map(({ elementId, targetTrackId }) => ({
 				trackId: targetTrackId,
-				elementId,
+				elementId: toElementId(elementId),
 			})),
 		);
 	}

apps/web/src/commands/timeline/element/split-elements.ts

@@ -3,7 +3,12 @@ import {
 	createElementSelectionResult,
 	type CommandResult,
 } from "@/commands/base-command";
-import type { SceneTracks, TimelineElement } from "@/timeline";
+import {
+	elementId,
+	type ElementRef,
+	type SceneTracks,
+	type TimelineElement,
+} from "@/model";
 import { generateUUID } from "@/utils/id";
 import { EditorCore } from "@/core";
 import { isRetimableElement } from "@/timeline";
@@ -12,7 +17,7 @@ import { getSourceSpanAtClipTime } from "@/retime";
 
 export class SplitElementsCommand extends Command {
 	private savedState: SceneTracks | null = null;
-	private rightSideElements: { trackId: string; elementId: string }[] = [];
+	private rightSideElements: ElementRef[] = [];
 	private readonly elements: { trackId: string; elementId: string }[];
 	private readonly splitTime: number;
 	private readonly retainSide: "both" | "left" | "right";
@@ -32,7 +37,7 @@ export class SplitElementsCommand extends Command {
 		this.retainSide = retainSide;
 	}
 
-	getRightSideElements(): { trackId: string; elementId: string }[] {
+	getRightSideElements(): ElementRef[] {
 		return this.rightSideElements;
 	}
 
@@ -107,7 +112,7 @@ export class SplitElementsCommand extends Command {
 						},
 					];
 				} else if (this.retainSide === "right") {
-					const newId = generateUUID();
+					const newId = elementId(generateUUID());
 					this.rightSideElements.push({
 						trackId: track.id,
 						elementId: newId,
@@ -126,7 +131,7 @@ export class SplitElementsCommand extends Command {
 					];
 				} else {
 					// "both" - split into two pieces
-					const secondElementId = generateUUID();
+					const secondElementId = elementId(generateUUID());
 					this.rightSideElements.push({
 						trackId: track.id,
 						elementId: secondElementId,

apps/web/src/commands/timeline/element/toggle-source-audio-separation.ts

@@ -10,11 +10,12 @@ import {
 	resolveTrackPlacement,
 } from "@/timeline/placement";
 import { updateElementInSceneTracks } from "@/timeline/track-element-update";
-import type {
+import {
-	SceneTracks,
+	elementId,
-	TimelineElement,
+	type SceneTracks,
-	VideoElement,
+	type TimelineElement,
-} from "@/timeline/types";
+	type VideoElement,
+} from "@/model";
 import { generateUUID } from "@/utils/id";
 
 export class ToggleSourceAudioSeparationCommand extends Command {
@@ -75,7 +76,7 @@ export class ToggleSourceAudioSeparationCommand extends Command {
 			...buildSeparatedAudioElement({
 				sourceElement: videoElement,
 			}),
-			id: generateUUID(),
+			id: elementId(generateUUID()),
 		};
 		const placementResult = resolveTrackPlacement({
 			tracks: this.savedState,

apps/web/src/commands/timeline/element/update-elements.ts

@@ -1,6 +1,6 @@
 import { EditorCore } from "@/core";
 import { Command, type CommandResult } from "@/commands/base-command";
-import type { SceneTracks, TimelineElement } from "@/timeline";
+import type { SceneTracks, TimelineElement } from "@/model";
 import {
 	findTrackInSceneTracks,
 	updateElementInSceneTracks,

apps/web/src/commands/timeline/track/add-track.ts

@@ -1,5 +1,5 @@
 import { Command, type CommandResult } from "@/commands/base-command";
-import type { SceneTracks, TrackType } from "@/timeline";
+import type { SceneTracks, TrackType } from "@/model";
 import { generateUUID } from "@/utils/id";
 import { EditorCore } from "@/core";
 import {

apps/web/src/commands/timeline/track/remove-track.ts

@@ -1,6 +1,6 @@
 import { Command, type CommandResult } from "@/commands/base-command";
 import { EditorCore } from "@/core";
-import type { SceneTracks } from "@/timeline";
+import type { SceneTracks } from "@/model";
 
 export class RemoveTrackCommand extends Command {
 	private savedState: SceneTracks | null = null;

apps/web/src/commands/timeline/track/toggle-track-mute.ts

@@ -1,5 +1,5 @@
 import { Command, type CommandResult } from "@/commands/base-command";
-import type { SceneTracks } from "@/timeline";
+import type { SceneTracks } from "@/model";
 import { EditorCore } from "@/core";
 import { canTrackHaveAudio, findTrackInSceneTracks, updateTrackInSceneTracks } from "@/timeline";
 

apps/web/src/commands/timeline/track/toggle-track-visibility.ts

@@ -1,5 +1,5 @@
 import { Command, type CommandResult } from "@/commands/base-command";
-import type { SceneTracks } from "@/timeline";
+import type { SceneTracks } from "@/model";
 import { EditorCore } from "@/core";
 import { canTrackBeHidden, findTrackInSceneTracks, updateTrackInSceneTracks } from "@/timeline";
 

apps/web/src/commands/timeline/tracks-snapshot.ts

@@ -1,5 +1,5 @@
 import { Command, type CommandResult } from "@/commands/base-command";
-import type { SceneTracks } from "@/timeline";
+import type { SceneTracks } from "@/model";
 import { EditorCore } from "@/core";
 
 export class TracksSnapshotCommand extends Command {

apps/web/src/components/editor/panels/assets/views/assets.tsx

@@ -45,7 +45,7 @@ import {
 	type MediaViewMode,
 	useAssetsPanelStore,
 } from "@/components/editor/panels/assets/assets-panel-store";
-import { MASKABLE_ELEMENT_TYPES } from "@/timeline";
+import { MASKABLE_ELEMENT_TYPES } from "@/model";
 import type { MediaAsset } from "@/media/types";
 import { cn } from "@/utils/ui";
 import {

apps/web/src/components/editor/panels/properties/hooks/use-keyframed-color-property.ts

@@ -4,7 +4,7 @@ import {
 	hasKeyframesForPath,
 } from "@/animation";
 import type { AnimationPropertyPath, ElementAnimations } from "@/animation/types";
-import type { TimelineElement } from "@/timeline";
+import type { TimelineElement } from "@/model";
 import { upsertElementKeyframe } from "@/timeline/animation-properties";
 
 export function useKeyframedColorProperty({

apps/web/src/components/editor/panels/properties/hooks/use-keyframed-number-property.ts

@@ -4,7 +4,7 @@ import {
 	hasKeyframesForPath,
 } from "@/animation";
 import type { AnimationPropertyPath, ElementAnimations } from "@/animation/types";
-import type { TimelineElement } from "@/timeline";
+import type { TimelineElement } from "@/model";
 import { upsertElementKeyframe } from "@/timeline/animation-properties";
 import { snapToStep } from "@/utils/math";
 import { usePropertyDraft } from "./use-property-draft";

apps/web/src/components/editor/panels/properties/hooks/use-keyframed-param-property.ts

@@ -16,7 +16,7 @@ import {
 	getAnimationParamValueKind,
 } from "@/animation/animated-params";
 import type { ParamDefinition } from "@/params";
-import type { TimelineElement } from "@/timeline";
+import type { TimelineElement } from "@/model";
 
 export interface KeyframedParamPropertyResult {
 	hasAnimatedKeyframes: boolean;

apps/web/src/components/editor/panels/properties/registry.tsx

@@ -1,17 +1,5 @@
 import type { ReactNode } from "react";
-import type {
+import type { AudioElement, EffectElement, GraphicElement, ImageElement, MaskableElement, RetimableElement, StickerElement, TextElement, TimelineElement, VideoElement, VisualElement } from "@/model";
-	EffectElement,
-	GraphicElement,
-	ImageElement,
-	MaskableElement,
-	RetimableElement,
-	StickerElement,
-	TextElement,
-	VisualElement,
-	VideoElement,
-	AudioElement,
-	TimelineElement,
-} from "@/timeline";
 import type { MediaAsset } from "@/media/types";
 import { HugeiconsIcon } from "@hugeicons/react";
 import {

apps/web/src/core/managers/commands.ts

@@ -2,7 +2,7 @@ import type { EditorCore } from "@/core";
 import type { Command, CommandResult } from "@/commands";
 import type { EditorSelectionSnapshot } from "@/selection/editor-selection";
 import { applyRippleAdjustments, computeRippleAdjustments } from "@/ripple";
-import type { SceneTracks } from "@/timeline/types";
+import type { SceneTracks } from "@/model";
 
 interface CommandHistoryEntry {
 	command: Command;

apps/web/src/core/managers/scenes-manager.ts

@@ -1,5 +1,5 @@
 import type { EditorCore } from "@/core";
-import type { SceneTracks, TScene } from "@/timeline";
+import type { SceneTracks, TScene } from "@/model";
 import { storageService } from "@/services/storage/service";
 import {
 	getMainScene,

apps/web/src/core/managers/selection-manager.ts

@@ -6,7 +6,7 @@ import type {
 	EditorSelectionSnapshot,
 	SelectedMaskPointSelection,
 } from "@/selection/editor-selection";
-import type { ElementRef } from "@/timeline/types";
+import type { ElementRef } from "@/model";
 
 export class SelectionManager {
 	private selectedElements: ElementRef[] = [];

apps/web/src/core/managers/timeline-manager.ts

@@ -1,13 +1,7 @@
 import type { EditorCore } from "@/core";
 import type { ElementBounds } from "@/preview/element-bounds";
 import type { ParamValues } from "@/params";
-import type {
+import type { RetimeConfig, SceneTracks, TimelineElement, TimelineTrack, TrackType } from "@/model";
-	SceneTracks,
-	TrackType,
-	TimelineTrack,
-	TimelineElement,
-	RetimeConfig,
-} from "@/timeline";
 import { calculateTotalDuration } from "@/timeline";
 import { TimelineDragSource } from "@/timeline/drag-source";
 import { findTrackInSceneTracks } from "@/timeline/track-element-update";

apps/web/src/effects/components/effects-tab.tsx

@@ -3,7 +3,7 @@
 import { useState } from "react";
 import type { ParamValues } from "@/params";
 import type { Effect } from "@/effects/types";
-import type { EffectElement, VisualElement } from "@/timeline";
+import type { EffectElement, VisualElement } from "@/model";
 import { effectsRegistry } from "@/effects";
 import { useEditor } from "@/editor/use-editor";
 import { useElementPreview } from "@/timeline/hooks/use-element-preview";

apps/web/src/effects/index.ts

@@ -3,7 +3,7 @@ import { buildDefaultParamValues } from "@/params/registry";
 import { effectsRegistry } from "./registry";
 import type { ParamValues } from "@/params";
 import type { Effect, EffectDefinition, EffectPass } from "@/effects/types";
-import { VISUAL_ELEMENT_TYPES } from "@/timeline";
+import { VISUAL_ELEMENT_TYPES } from "@/model";
 
 export { effectsRegistry } from "./registry";
 export { registerDefaultEffects } from "./definitions";

apps/web/src/graphics/components/graphic-tab.tsx

@@ -7,7 +7,7 @@ import {
 	type KeyframedParamPropertyResult,
 } from "@/components/editor/panels/properties/hooks/use-keyframed-param-property";
 import type { ParamDefinition, ParamValues } from "@/params";
-import type { GraphicElement } from "@/timeline";
+import type { GraphicElement } from "@/model";
 import {
 	graphicsRegistry,
 	registerDefaultGraphics,

apps/web/src/masks/components/masks-tab.tsx

@@ -1,6 +1,6 @@
 "use client";
 
-import type { MaskableElement } from "@/timeline";
+import type { MaskableElement } from "@/model";
 import type { Mask, MaskType, TextMask } from "@/masks/types";
 import type { NumberParamDefinition, SelectParamDefinition } from "@/params";
 import { masksRegistry, buildDefaultMaskInstance } from "@/masks";

apps/web/src/masks/geometry.ts

@@ -1,5 +1,5 @@
 import type { ElementBounds } from "@/preview/element-bounds";
-import type { SnapLine } from "@/preview/preview-snap";
+import type { PreviewSnapLine } from "@/preview/preview-snap";
 import { MIN_MASK_DIMENSION } from "@/masks/dimensions";
 import type { RectangleMaskParams } from "@/masks/types";
 
@@ -100,10 +100,10 @@ export function toGlobalMaskSnapLines({
 	bounds,
 	canvasSize,
 }: {
-	lines: SnapLine[];
+	lines: PreviewSnapLine[];
 	bounds: ElementBounds;
 	canvasSize: { width: number; height: number };
-}): SnapLine[] {
+}): PreviewSnapLine[] {
 	const centerX = bounds.cx - canvasSize.width / 2;
 	const centerY = bounds.cy - canvasSize.height / 2;
 

apps/web/src/masks/snap.ts

@@ -6,7 +6,7 @@ import {
 	snapScale,
 	snapScaleAxes,
 	type ScaleEdgePreference,
-	type SnapLine,
+	type PreviewSnapLine,
 } from "@/preview/preview-snap";
 import type { RectangleMaskParams, SplitMaskParams } from "@/masks/types";
 import {
@@ -20,7 +20,7 @@ type SharedMaskParams = SplitMaskParams | RectangleMaskParams;
 
 type MaskSnapResult<TParams extends SharedMaskParams> = {
 	params: TParams;
-	activeLines: SnapLine[];
+	activeLines: PreviewSnapLine[];
 };
 
 const CORNER_SIZE_HANDLES = new Set([

apps/web/src/masks/types.ts

@@ -1,5 +1,5 @@
 import type { ElementBounds } from "@/preview/element-bounds";
-import type { SnapLine } from "@/preview/preview-snap";
+import type { PreviewSnapLine } from "@/preview/preview-snap";
 import type { ParamDefinition } from "@/params";
 import type { CustomMaskPathPoint } from "@/masks/custom-path";
 import type {
@@ -261,7 +261,7 @@ export interface MaskSnapResult<
 	TParams extends BaseMaskParams = BaseMaskParams,
 > {
 	params: TParams;
-	activeLines: SnapLine[];
+	activeLines: PreviewSnapLine[];
 }
 
 export interface MaskInteractionResult {

apps/web/src/masks/use-mask-handles.ts

@@ -14,11 +14,11 @@ import {
 } from "@/preview/element-bounds";
 import {
 	SNAP_THRESHOLD_SCREEN_PIXELS,
-	type SnapLine,
+	type PreviewSnapLine,
 } from "@/preview/preview-snap";
 import type { SelectedMaskPointSelection } from "@/selection/editor-selection";
 import type { Mask, MaskInteractionResult } from "@/masks/types";
-import type { MaskableElement } from "@/timeline";
+import type { MaskableElement } from "@/model";
 import { registerCanceller } from "@/editor/cancel-interaction";
 
 interface DragState {
@@ -94,7 +94,7 @@ function withUpdatedMaskParams<TMask extends Mask>({
 export function useMaskHandles({
 	onSnapLinesChange,
 }: {
-	onSnapLinesChange?: (lines: SnapLine[]) => void;
+	onSnapLinesChange?: (lines: PreviewSnapLine[]) => void;
 }) {
 	const editor = useEditor();
 	const isShiftHeldRef = useShiftKey();
@@ -552,7 +552,7 @@ export function useMaskHandles({
 				screenPixels: SNAP_THRESHOLD_SCREEN_PIXELS,
 			});
 			const { params: nextParams, activeLines } = isShiftHeldRef.current
-				? { params: proposedParams, activeLines: [] as SnapLine[] }
+				? { params: proposedParams, activeLines: [] as PreviewSnapLine[] }
 				: (def.interaction.snap?.({
 						handleId: drag.handleId,
 						startParams: drag.startParams,
@@ -560,7 +560,7 @@ export function useMaskHandles({
 						bounds: selectedWithMask.bounds,
 						canvasSize,
 						snapThreshold,
-					}) ?? { params: proposedParams, activeLines: [] as SnapLine[] });
+					}) ?? { params: proposedParams, activeLines: [] as PreviewSnapLine[] });
 
 			onSnapLinesChange?.(activeLines);
 

apps/web/src/media/audio.ts

@@ -1,10 +1,4 @@
-import type {
+import type { AudioElement, LibraryAudioElement, RetimeConfig, SceneTracks, VideoElement } from "@/model";
-	AudioElement,
-	VideoElement,
-	LibraryAudioElement,
-	RetimeConfig,
-	SceneTracks,
-} from "@/timeline";
 import { shouldMaintainPitch } from "@/retime/rate";
 import type { MediaAsset } from "@/media/types";
 import { applyAudioMasteringToBuffer } from "@/media/audio-mastering";

apps/web/src/media/mediabunny.ts

@@ -6,7 +6,7 @@ import {
 	type VideoCodec,
 } from "mediabunny";
 import { createTimelineAudioBuffer } from "@/media/audio";
-import type { SceneTracks } from "@/timeline";
+import type { SceneTracks } from "@/model";
 import type { MediaAsset } from "@/media/types";
 import { TICKS_PER_SECOND } from "@/wasm";
 import { renderThumbnailDataUrl } from "./thumbnail";

apps/web/src/media/waveform-summary.ts

@@ -1,7 +1,7 @@
 "use client";
 
 import { getSourceTimeAtClipTime } from "@/retime";
-import type { RetimeConfig } from "@/timeline";
+import type { RetimeConfig } from "@/model";
 
 const RMS_ANALYSIS_WINDOW_SECONDS = 0.02;
 const DEFAULT_SOURCE_WAVEFORM_BUCKET_SIZE = 128;

apps/web/src/model/bookmark.ts

@@ -0,0 +1,6 @@
+export interface Bookmark {
+	time: number;
+	note?: string;
+	color?: string;
+	duration?: number;
+}

apps/web/src/model/element-ref.ts

@@ -0,0 +1,6 @@
+import type { ElementId } from "./ids";
+
+export type ElementRef = {
+	trackId: string;
+	elementId: ElementId;
+};

apps/web/src/model/elements/audio.ts

@@ -0,0 +1,21 @@
+import type { BaseTimelineElement, RetimeConfig } from "./base";
+
+export interface BaseAudioElement extends BaseTimelineElement {
+	type: "audio";
+	volume: number;
+	muted?: boolean;
+	buffer?: AudioBuffer;
+	retime?: RetimeConfig;
+}
+
+export interface UploadAudioElement extends BaseAudioElement {
+	sourceType: "upload";
+	mediaId: string;
+}
+
+export interface LibraryAudioElement extends BaseAudioElement {
+	sourceType: "library";
+	sourceUrl: string;
+}
+
+export type AudioElement = UploadAudioElement | LibraryAudioElement;

apps/web/src/model/elements/base.ts

@@ -0,0 +1,18 @@
+import type { ElementAnimations } from "@/animation/types";
+import type { ElementId } from "../ids";
+
+export interface BaseTimelineElement {
+	id: ElementId;
+	name: string;
+	duration: number;
+	startTime: number;
+	trimStart: number;
+	trimEnd: number;
+	sourceDuration?: number;
+	animations?: ElementAnimations;
+}
+
+export interface RetimeConfig {
+	rate: number;
+	maintainPitch?: boolean;
+}

apps/web/src/model/elements/effect.ts

@@ -0,0 +1,8 @@
+import type { ParamValues } from "@/params";
+import type { BaseTimelineElement } from "./base";
+
+export interface EffectElement extends BaseTimelineElement {
+	type: "effect";
+	effectType: string;
+	params: ParamValues;
+}

apps/web/src/model/elements/graphic.ts

@@ -0,0 +1,17 @@
+import type { Effect } from "@/effects/types";
+import type { Mask } from "@/masks/types";
+import type { ParamValues } from "@/params";
+import type { BlendMode, Transform } from "@/rendering";
+import type { BaseTimelineElement } from "./base";
+
+export interface GraphicElement extends BaseTimelineElement {
+	type: "graphic";
+	definitionId: string;
+	params: ParamValues;
+	hidden?: boolean;
+	transform: Transform;
+	opacity: number;
+	blendMode?: BlendMode;
+	effects?: Effect[];
+	masks?: Mask[];
+}

apps/web/src/model/elements/image.ts

@@ -0,0 +1,15 @@
+import type { Effect } from "@/effects/types";
+import type { Mask } from "@/masks/types";
+import type { BlendMode, Transform } from "@/rendering";
+import type { BaseTimelineElement } from "./base";
+
+export interface ImageElement extends BaseTimelineElement {
+	type: "image";
+	mediaId: string;
+	hidden?: boolean;
+	transform: Transform;
+	opacity: number;
+	blendMode?: BlendMode;
+	effects?: Effect[];
+	masks?: Mask[];
+}

apps/web/src/model/elements/index.ts

@@ -0,0 +1,84 @@
+import type { AudioElement, LibraryAudioElement, UploadAudioElement } from "./audio";
+import type { EffectElement } from "./effect";
+import type { GraphicElement } from "./graphic";
+import type { ImageElement } from "./image";
+import type { StickerElement } from "./sticker";
+import type { TextElement } from "./text";
+import type { VideoElement } from "./video";
+import type { Transform } from "@/rendering";
+
+export * from "./audio";
+export * from "./base";
+export * from "./effect";
+export * from "./graphic";
+export * from "./image";
+export * from "./sticker";
+export * from "./text";
+export * from "./video";
+
+export type ElementUpdatePatch =
+	| { transform: Transform }
+	| { opacity: number }
+	| { volume: number };
+
+export type TimelineElement =
+	| AudioElement
+	| VideoElement
+	| ImageElement
+	| TextElement
+	| StickerElement
+	| GraphicElement
+	| EffectElement;
+
+export type ElementType = TimelineElement["type"];
+
+function elementTypes<T extends ElementType[]>(...types: T): T {
+	return types;
+}
+
+export const MASKABLE_ELEMENT_TYPES = elementTypes("video", "image", "graphic");
+
+export type MaskableElement = Extract<
+	TimelineElement,
+	{ type: (typeof MASKABLE_ELEMENT_TYPES)[number] }
+>;
+
+export const RETIMABLE_ELEMENT_TYPES = elementTypes("video", "audio");
+
+export type RetimableElement = Extract<
+	TimelineElement,
+	{ type: (typeof RETIMABLE_ELEMENT_TYPES)[number] }
+>;
+
+export const VISUAL_ELEMENT_TYPES = elementTypes(
+	"video",
+	"image",
+	"text",
+	"sticker",
+	"graphic",
+);
+
+export type VisualElement = Extract<
+	TimelineElement,
+	{ type: (typeof VISUAL_ELEMENT_TYPES)[number] }
+>;
+
+export type CreateUploadAudioElement = Omit<UploadAudioElement, "id">;
+export type CreateLibraryAudioElement = Omit<LibraryAudioElement, "id">;
+export type CreateAudioElement =
+	| CreateUploadAudioElement
+	| CreateLibraryAudioElement;
+export type CreateVideoElement = Omit<VideoElement, "id">;
+export type CreateImageElement = Omit<ImageElement, "id">;
+export type CreateTextElement = Omit<TextElement, "id">;
+export type CreateStickerElement = Omit<StickerElement, "id">;
+export type CreateGraphicElement = Omit<GraphicElement, "id">;
+export type CreateEffectElement = Omit<EffectElement, "id">;
+export type CreateTimelineElement =
+	| CreateAudioElement
+	| CreateVideoElement
+	| CreateImageElement
+	| CreateTextElement
+	| CreateStickerElement
+	| CreateGraphicElement
+	| CreateEffectElement;

apps/web/src/model/elements/sticker.ts

@@ -0,0 +1,16 @@
+import type { Effect } from "@/effects/types";
+import type { BlendMode, Transform } from "@/rendering";
+import type { BaseTimelineElement } from "./base";
+
+export interface StickerElement extends BaseTimelineElement {
+	type: "sticker";
+	stickerId: string;
+	/** Natural dimensions of the sticker asset, stored at insert time. Used by renderer and preview bounds to avoid split-brain geometry. */
+	intrinsicWidth?: number;
+	intrinsicHeight?: number;
+	hidden?: boolean;
+	transform: Transform;
+	opacity: number;
+	blendMode?: BlendMode;
+	effects?: Effect[];
+}

apps/web/src/model/elements/text.ts

@@ -0,0 +1,33 @@
+import type { Effect } from "@/effects/types";
+import type { BlendMode, Transform } from "@/rendering";
+import type { BaseTimelineElement } from "./base";
+
+export interface TextBackground {
+	enabled: boolean;
+	color: string;
+	cornerRadius?: number;
+	paddingX?: number;
+	paddingY?: number;
+	offsetX?: number;
+	offsetY?: number;
+}
+
+export interface TextElement extends BaseTimelineElement {
+	type: "text";
+	content: string;
+	fontSize: number;
+	fontFamily: string;
+	color: string;
+	background: TextBackground;
+	textAlign: "left" | "center" | "right";
+	fontWeight: "normal" | "bold";
+	fontStyle: "normal" | "italic";
+	textDecoration: "none" | "underline" | "line-through";
+	letterSpacing?: number;
+	lineHeight?: number;
+	hidden?: boolean;
+	transform: Transform;
+	opacity: number;
+	blendMode?: BlendMode;
+	effects?: Effect[];
+}

apps/web/src/model/elements/video.ts

@@ -0,0 +1,19 @@
+import type { Effect } from "@/effects/types";
+import type { Mask } from "@/masks/types";
+import type { BlendMode, Transform } from "@/rendering";
+import type { BaseTimelineElement, RetimeConfig } from "./base";
+
+export interface VideoElement extends BaseTimelineElement {
+	type: "video";
+	mediaId: string;
+	volume?: number;
+	muted?: boolean;
+	isSourceAudioEnabled?: boolean;
+	hidden?: boolean;
+	retime?: RetimeConfig;
+	transform: Transform;
+	opacity: number;
+	blendMode?: BlendMode;
+	effects?: Effect[];
+	masks?: Mask[];
+}

apps/web/src/model/ids.ts

@@ -0,0 +1,15 @@
+export type ElementId = string & { readonly __brand: "ElementId" };
+export type TrackId = string & { readonly __brand: "TrackId" };
+export type SceneId = string & { readonly __brand: "SceneId" };
+
+export function elementId(value: string): ElementId {
+	return value as ElementId;
+}
+
+export function trackId(value: string): TrackId {
+	return value as TrackId;
+}
+
+export function sceneId(value: string): SceneId {
+	return value as SceneId;
+}

apps/web/src/model/index.ts

@@ -0,0 +1,7 @@
+export * from "./bookmark";
+export * from "./element-ref";
+export * from "./elements";
+export * from "./ids";
+export * from "./scene";
+export * from "./time";
+export * from "./track";

apps/web/src/model/scene.ts

@@ -0,0 +1,12 @@
+import type { Bookmark } from "./bookmark";
+import type { SceneTracks } from "./track";
+
+export interface TScene {
+	id: string;
+	name: string;
+	isMain: boolean;
+	tracks: SceneTracks;
+	bookmarks: Bookmark[];
+	createdAt: Date;
+	updatedAt: Date;
+}

apps/web/src/model/time.ts

@@ -0,0 +1,5 @@
+export type MediaTime = number & { readonly __brand: "MediaTime" };
+
+export function mediaTime(value: number): MediaTime {
+	return value as MediaTime;
+}

apps/web/src/model/track.ts

@@ -0,0 +1,62 @@
+import type {
+	AudioElement,
+	EffectElement,
+	GraphicElement,
+	ImageElement,
+	StickerElement,
+	TextElement,
+	VideoElement,
+} from "./elements";
+
+export type TrackType = "video" | "text" | "audio" | "graphic" | "effect";
+
+export interface BaseTrack {
+	id: string;
+	name: string;
+}
+
+export interface VideoTrack extends BaseTrack {
+	type: "video";
+	elements: (VideoElement | ImageElement)[];
+	muted: boolean;
+	hidden: boolean;
+}
+
+export interface TextTrack extends BaseTrack {
+	type: "text";
+	elements: TextElement[];
+	hidden: boolean;
+}
+
+export interface AudioTrack extends BaseTrack {
+	type: "audio";
+	elements: AudioElement[];
+	muted: boolean;
+}
+
+export interface GraphicTrack extends BaseTrack {
+	type: "graphic";
+	elements: (StickerElement | GraphicElement)[];
+	hidden: boolean;
+}
+
+export interface EffectTrack extends BaseTrack {
+	type: "effect";
+	elements: EffectElement[];
+	hidden: boolean;
+}
+
+export type TimelineTrack =
+	| VideoTrack
+	| TextTrack
+	| AudioTrack
+	| GraphicTrack
+	| EffectTrack;
+
+export type OverlayTrack = VideoTrack | TextTrack | GraphicTrack | EffectTrack;
+
+export interface SceneTracks {
+	overlay: OverlayTrack[];
+	main: VideoTrack;
+	audio: AudioTrack[];
+}

apps/web/src/preview/components/mask-handles.tsx

@@ -3,7 +3,7 @@
 import { PEN_CURSOR } from "@/preview/components/cursors";
 import { usePreviewViewport } from "@/preview/components/preview-viewport";
 import { useMaskHandles } from "@/masks/use-mask-handles";
-import type { SnapLine } from "@/preview/preview-snap";
+import type { PreviewSnapLine } from "@/preview/preview-snap";
 import {
 	CornerHandle,
 	CircleHandle,
@@ -22,7 +22,7 @@ import { Rotate01Icon, FeatherIcon } from "@hugeicons/core-free-icons";
 export function MaskHandles({
 	onSnapLinesChange,
 }: {
-	onSnapLinesChange?: (lines: SnapLine[]) => void;
+	onSnapLinesChange?: (lines: PreviewSnapLine[]) => void;
 }) {
 	const viewport = usePreviewViewport();
 	const {

apps/web/src/preview/components/preview-interaction-overlay.tsx

@@ -1,7 +1,7 @@
 import { useState } from "react";
 import { usePreviewViewport } from "@/preview/components/preview-viewport";
 import { usePreviewInteraction } from "@/preview/hooks/use-preview-interaction";
-import type { SnapLine } from "@/preview/preview-snap";
+import type { PreviewSnapLine } from "@/preview/preview-snap";
 import { TransformHandles } from "./transform-handles";
 import { MaskHandles } from "./mask-handles";
 import { SnapGuides } from "./snap-guides";
@@ -10,7 +10,7 @@ import { usePropertiesStore } from "@/components/editor/panels/properties/stores
 import { useEditor } from "@/editor/use-editor";
 
 export function PreviewInteractionOverlay() {
-	const [snapLines, setSnapLines] = useState<SnapLine[]>([]);
+	const [snapLines, setSnapLines] = useState<PreviewSnapLine[]>([]);
 	const editor = useEditor();
 	const viewport = usePreviewViewport();
 	const selectedElements = useEditor((e) => e.selection.getSelectedElements());

apps/web/src/preview/components/snap-guides.tsx

@@ -1,9 +1,9 @@
 "use client";
 
 import { usePreviewViewport } from "@/preview/components/preview-viewport";
-import type { SnapLine } from "@/preview/preview-snap";
+import type { PreviewSnapLine } from "@/preview/preview-snap";
 
-export function SnapGuides({ lines }: { lines: SnapLine[] }) {
+export function SnapGuides({ lines }: { lines: PreviewSnapLine[] }) {
 	const viewport = usePreviewViewport();
 
 	if (lines.length === 0) {

apps/web/src/preview/components/text-edit-overlay.tsx

@@ -3,7 +3,7 @@
 import { useCallback, useEffect, useRef } from "react";
 import { usePreviewViewport } from "@/preview/components/preview-viewport";
 import { useEditor } from "@/editor/use-editor";
-import type { TextElement } from "@/timeline";
+import type { TextElement } from "@/model";
 import { DEFAULTS } from "@/timeline/defaults";
 import {
 	getElementLocalTime,

apps/web/src/preview/controllers/preview-interaction-controller.ts

@@ -15,19 +15,12 @@ import {
 import {
 	SNAP_THRESHOLD_SCREEN_PIXELS,
 	snapPosition,
-	type SnapLine,
+	type PreviewSnapLine,
 } from "@/preview/preview-snap";
 import type { TCanvasSize } from "@/project/types";
 import type { Transform } from "@/rendering";
 import { isVisualElement } from "@/timeline/element-utils";
-import type {
+import type { ElementRef, SceneTracks, TextElement, TimelineElement, TimelineTrack, VisualElement } from "@/model";
-	ElementRef,
-	SceneTracks,
-	TextElement,
-	TimelineElement,
-	TimelineTrack,
-	VisualElement,
-} from "@/timeline";
 
 const MIN_DRAG_DISTANCE = 0.5;
 const PRIMARY_POINTER_BUTTON = 0;
@@ -133,7 +126,7 @@ export interface PlaybackApi {
 
 export interface PreviewOptions {
 	isMaskMode: () => boolean;
-	onSnapLinesChange?: (lines: SnapLine[]) => void;
+	onSnapLinesChange?: (lines: PreviewSnapLine[]) => void;
 }
 
 export interface PreviewInteractionDeps {
@@ -554,7 +547,7 @@ export class PreviewInteractionController {
 				})
 			: {
 					snappedPosition: proposedPosition,
-					activeLines: [] as SnapLine[],
+					activeLines: [] as PreviewSnapLine[],
 				};
 
 		this.deps.preview.onSnapLinesChange?.(activeLines);

apps/web/src/preview/controllers/transform-handle-controller.ts

@@ -14,7 +14,7 @@ import {
 	snapScale,
 	snapScaleAxes,
 	type ScaleEdgePreference,
-	type SnapLine,
+	type PreviewSnapLine,
 } from "@/preview/preview-snap";
 import { isVisualElement } from "@/timeline/element-utils";
 import {
@@ -25,12 +25,7 @@ import {
 import type { ElementAnimations } from "@/animation/types";
 import type { Transform } from "@/rendering";
 import { resolveTransformAtTime } from "@/rendering/animation-values";
-import type {
+import type { ElementRef, SceneTracks, TimelineElement, VisualElement } from "@/model";
-	ElementRef,
-	SceneTracks,
-	TimelineElement,
-	VisualElement,
-} from "@/timeline";
 
 type Point = { readonly x: number; readonly y: number };
 type CanvasSize = { readonly width: number; readonly height: number };
@@ -137,7 +132,7 @@ export interface TimelineOps {
 }
 
 export interface PreviewOptions {
-	onSnapLinesChange?: (lines: SnapLine[]) => void;
+	onSnapLinesChange?: (lines: PreviewSnapLine[]) => void;
 }
 
 export interface TransformHandleDeps {
@@ -590,7 +585,7 @@ export class TransformHandleController {
 			screenPixels: SNAP_THRESHOLD_SCREEN_PIXELS,
 		});
 		const { snappedScale, activeLines } = this.deps.input.isShiftHeld()
-			? { snappedScale: scaleFactor, activeLines: [] as SnapLine[] }
+			? { snappedScale: scaleFactor, activeLines: [] as PreviewSnapLine[] }
 			: snapScale({
 					proposedScale: scaleFactor,
 					position: session.initialTransform.position,
@@ -670,12 +665,12 @@ export class TransformHandleController {
 					x: {
 						snappedScale: proposedScaleX,
 						snapDistance: Infinity,
-						activeLines: [] as SnapLine[],
+						activeLines: [] as PreviewSnapLine[],
 					},
 					y: {
 						snappedScale: proposedScaleY,
 						snapDistance: Infinity,
-						activeLines: [] as SnapLine[],
+						activeLines: [] as PreviewSnapLine[],
 					},
 				}
 			: snapScaleAxes({

apps/web/src/preview/element-bounds.ts

@@ -1,4 +1,4 @@
-import type { SceneTracks, TimelineElement } from "@/timeline";
+import type { ElementId, SceneTracks, TimelineElement } from "@/model";
 import type { MediaAsset } from "@/media/types";
 import { STICKER_INTRINSIC_SIZE_FALLBACK } from "@/stickers/intrinsic-size";
 import { DEFAULT_GRAPHIC_SOURCE_SIZE } from "@/graphics";
@@ -18,7 +18,7 @@ export interface ElementBounds {
 
 export interface ElementWithBounds {
 	trackId: string;
-	elementId: string;
+	elementId: ElementId;
 	element: TimelineElement;
 	bounds: ElementBounds;
 }

apps/web/src/preview/hit-test.ts

@@ -1,5 +1,5 @@
 import type { ElementWithBounds } from "./element-bounds";
-import type { ElementRef } from "@/timeline/types";
+import type { ElementRef } from "@/model";
 
 function pointInRotatedRect({
 	px,

apps/web/src/preview/hooks/use-preview-interaction.ts

@@ -2,7 +2,7 @@ import { useEffect, useReducer, useRef } from "react";
 import { useEditor } from "@/editor/use-editor";
 import { useShiftKey } from "@/hooks/use-shift-key";
 import { usePreviewViewport } from "@/preview/components/preview-viewport";
-import type { SnapLine } from "@/preview/preview-snap";
+import type { PreviewSnapLine } from "@/preview/preview-snap";
 import { registerCanceller } from "@/editor/cancel-interaction";
 import {
 	PreviewInteractionController,
@@ -10,7 +10,7 @@ import {
 	type PreviewInteractionDepsRef,
 } from "@/preview/controllers/preview-interaction-controller";
 
-export type OnSnapLinesChange = (lines: SnapLine[]) => void;
+export type OnSnapLinesChange = (lines: PreviewSnapLine[]) => void;
 
 export function usePreviewInteraction({
 	onSnapLinesChange,

apps/web/src/preview/preview-snap.ts

@@ -1,4 +1,4 @@
-export interface SnapLine {
+export interface PreviewSnapLine {
 	type: "horizontal" | "vertical";
 	position: number;
 }
@@ -8,9 +8,9 @@ const ROTATION_SNAP_THRESHOLD_DEGREES = 5;
 export const MIN_SCALE = 0.01;
 export const SNAP_THRESHOLD_SCREEN_PIXELS = 8;
 
-export interface SnapResult {
+export interface PreviewSnapResult {
 	snappedPosition: { x: number; y: number };
-	activeLines: SnapLine[];
+	activeLines: PreviewSnapLine[];
 }
 
 type ScaleEdge = "left" | "right" | "top" | "bottom";
@@ -78,7 +78,7 @@ export function snapPosition({
 	elementSize: { width: number; height: number };
 	rotation?: number;
 	snapThreshold: { x: number; y: number };
-}): SnapResult {
+}): PreviewSnapResult {
 	const centerX = 0;
 	const centerY = 0;
 	const left = -canvasSize.width / 2;
@@ -91,11 +91,11 @@ export function snapPosition({
 	const sinR = Math.abs(Math.sin(rotRad));
 	const halfWidth = (elementSize.width * cosR + elementSize.height * sinR) / 2;
 	const halfHeight = (elementSize.width * sinR + elementSize.height * cosR) / 2;
-	const activeLines: SnapLine[] = [];
+	const activeLines: PreviewSnapLine[] = [];
 
 	type AxisSnapCandidate = {
 		snappedPosition: number;
-		line: SnapLine;
+		line: PreviewSnapLine;
 		distance: number;
 	};
 
@@ -183,7 +183,7 @@ export function snapPosition({
 
 export interface ScaleSnapResult {
 	snappedScale: number;
-	activeLines: SnapLine[];
+	activeLines: PreviewSnapLine[];
 }
 
 export function snapScale({
@@ -226,7 +226,7 @@ export function snapScale({
 	interface SnapCandidate {
 		scale: number;
 		distance: number;
-		lines: SnapLine[];
+		lines: PreviewSnapLine[];
 		edge: ScaleEdge;
 	}
 
@@ -320,10 +320,10 @@ export function snapScale({
 	const snappedTop = position.y - aabbBaseHalfH * best.scale;
 	const snappedBottom = position.y + aabbBaseHalfH * best.scale;
 
-	const activeLines: SnapLine[] = [];
+	const activeLines: PreviewSnapLine[] = [];
 	const seenKeys = new Set<string>();
 
-	function addLine({ line }: { line: SnapLine }) {
+	function addLine({ line }: { line: PreviewSnapLine }) {
 		const key = `${line.type}-${line.position}`;
 		if (!seenKeys.has(key)) {
 			seenKeys.add(key);
@@ -368,7 +368,7 @@ export interface AxisSnapResult {
 	snappedScale: number;
 	/** Infinity when no snap candidate was within threshold */
 	snapDistance: number;
-	activeLines: SnapLine[];
+	activeLines: PreviewSnapLine[];
 }
 
 export function snapScaleAxes({
@@ -413,7 +413,7 @@ export function snapScaleAxes({
 	interface Candidate {
 		scale: number;
 		distance: number;
-		line: SnapLine;
+		line: PreviewSnapLine;
 		edge: ScaleEdge;
 	}
 
@@ -442,7 +442,7 @@ export function snapScaleAxes({
 
 	if (cosR > EPSILON) {
 		for (const T of [canvasLeft, 0, canvasRight]) {
-			const line: SnapLine = { type: "vertical", position: T };
+			const line: PreviewSnapLine = { type: "vertical", position: T };
 			const distLeft = Math.abs(currentLeftEdge - T);
 			if (distLeft <= snapThreshold.x) {
 				const scale = (2 * (position.x - T) - yContribW) / (baseWidth * cosR);
@@ -458,7 +458,7 @@ export function snapScaleAxes({
 
 	if (sinR > EPSILON) {
 		for (const T of [canvasTop, 0, canvasBottom]) {
-			const line: SnapLine = { type: "horizontal", position: T };
+			const line: PreviewSnapLine = { type: "horizontal", position: T };
 			const distTop = Math.abs(currentTopEdge - T);
 			if (distTop <= snapThreshold.y) {
 				const scale = (2 * (position.y - T) - yContribH) / (baseWidth * sinR);
@@ -480,7 +480,7 @@ export function snapScaleAxes({
 
 	if (sinR > EPSILON) {
 		for (const T of [canvasLeft, 0, canvasRight]) {
-			const line: SnapLine = { type: "vertical", position: T };
+			const line: PreviewSnapLine = { type: "vertical", position: T };
 			const distLeft = Math.abs(currentLeftEdge - T);
 			if (distLeft <= snapThreshold.x) {
 				const scale = (2 * (position.x - T) - xContribW) / (baseHeight * sinR);
@@ -496,7 +496,7 @@ export function snapScaleAxes({
 
 	if (cosR > EPSILON) {
 		for (const T of [canvasTop, 0, canvasBottom]) {
-			const line: SnapLine = { type: "horizontal", position: T };
+			const line: PreviewSnapLine = { type: "horizontal", position: T };
 			const distTop = Math.abs(currentTopEdge - T);
 			if (distTop <= snapThreshold.y) {
 				const scale = (2 * (position.y - T) - xContribH) / (baseHeight * cosR);

apps/web/src/project/types.ts

@@ -1,5 +1,5 @@
 import type { FrameRate } from "opencut-wasm";
-import type { TScene } from "@/timeline/types";
+import type { TScene } from "@/model";
 
 export type TBackground =
 	| {

apps/web/src/rendering/components/blending-tab.tsx

@@ -20,7 +20,7 @@ import {
 	SelectValue,
 } from "@/components/ui/select";
 import type { BlendMode } from "@/rendering";
-import type { ElementType } from "@/timeline";
+import type { ElementType } from "@/model";
 import type { ElementAnimations } from "@/animation/types";
 import { HugeiconsIcon } from "@hugeicons/react";
 import { RainDropIcon } from "@hugeicons/core-free-icons";

apps/web/src/rendering/components/transform-tab.tsx

@@ -1,7 +1,7 @@
 import { NumberField } from "@/components/ui/number-field";
 import { useEditor } from "@/editor/use-editor";
 import { clamp, isNearlyEqual } from "@/utils/math";
-import type { VisualElement } from "@/timeline";
+import type { VisualElement } from "@/model";
 import {
 	Section,
 	SectionContent,

apps/web/src/retime/__tests__/resolve.test.ts

@@ -5,7 +5,7 @@ import {
 	getSourceTimeAtClipTime,
 	getTimelineDurationForSourceSpan,
 } from "@/retime";
-import type { RetimeConfig } from "@/timeline";
+import type { RetimeConfig } from "@/model";
 
 const twoX: RetimeConfig = { rate: 2 };
 const halfX: RetimeConfig = { rate: 0.5 };

apps/web/src/retime/__tests__/split.test.ts

@@ -3,7 +3,7 @@ import {
 	getSourceSpanAtClipTime,
 	splitRetimeAtClipTime,
 } from "@/retime";
-import type { RetimeConfig } from "@/timeline";
+import type { RetimeConfig } from "@/model";
 
 describe("retime split", () => {
 	test("measures source span at a clip time", () => {

apps/web/src/retime/audio-stretch.ts

@@ -1,6 +1,6 @@
 import { PitchShifter } from "soundtouchjs";
 import { clampRetimeRate, shouldMaintainPitch } from "@/retime/rate";
-import type { RetimeConfig } from "@/timeline";
+import type { RetimeConfig } from "@/model";
 import { getSourceTimeAtClipTime } from "./resolve";
 
 const RATE_EPSILON = 1e-6;

apps/web/src/retime/presets.ts

@@ -1,4 +1,4 @@
-import type { RetimeConfig } from "@/timeline";
+import type { RetimeConfig } from "@/model";
 import { clampRetimeRate } from "@/retime/rate";
 
 export function buildConstantRetime({

apps/web/src/retime/resolve.ts

@@ -1,4 +1,4 @@
-import type { RetimeConfig } from "@/timeline";
+import type { RetimeConfig } from "@/model";
 import { clampRetimeRate } from "@/retime/rate";
 
 function getSafeRate({ rate }: { rate: number }): number {

apps/web/src/retime/split.ts

@@ -1,4 +1,4 @@
-import type { RetimeConfig } from "@/timeline";
+import type { RetimeConfig } from "@/model";
 import { getSourceTimeAtClipTime } from "./resolve";
 
 export function getSourceSpanAtClipTime({

apps/web/src/ripple/apply.ts

@@ -1,4 +1,4 @@
-import type { SceneTracks, TimelineTrack } from "@/timeline/types";
+import type { SceneTracks, TimelineTrack } from "@/model";
 import { rippleShiftElements } from "./shift";
 
 export interface RippleAdjustment {

apps/web/src/ripple/diff.ts

@@ -1,4 +1,4 @@
-import type { SceneTracks, TimelineElement, TimelineTrack } from "@/timeline/types";
+import type { SceneTracks, TimelineElement, TimelineTrack } from "@/model";
 import type { RippleAdjustment } from "./apply";
 
 interface Interval {

apps/web/src/ripple/shift.ts

@@ -1,4 +1,4 @@
-import type { TimelineElement } from "@/timeline/types";
+import type { TimelineElement } from "@/model";
 
 export function rippleShiftElements<TElement extends TimelineElement>({
 	elements,

apps/web/src/selection/editor-selection.ts

@@ -1,5 +1,5 @@
 import type { SelectedKeyframeRef } from "@/animation/types";
-import type { ElementRef } from "@/timeline/types";
+import type { ElementRef } from "@/model";
 
 export interface SelectedMaskPointSelection {
 	trackId: string;

apps/web/src/services/renderer/nodes/blur-background-node.ts

@@ -1,5 +1,5 @@
 import type { EffectPass } from "@/effects/types";
-import type { RetimeConfig } from "@/timeline";
+import type { RetimeConfig } from "@/model";
 import { BaseNode } from "./base-node";
 
 export type BlurBackgroundNodeParams = {