1 files changed, 609 insertions, 609 deletions
diff --git a/apps/web/src/hooks/timeline/use-timeline-drag-drop.ts b/apps/web/src/hooks/timeline/use-timeline-drag-drop.ts
index 7cd9f140..9693e8d8 100644
--- a/apps/web/src/hooks/timeline/use-timeline-drag-drop.ts
+++ b/apps/web/src/hooks/timeline/use-timeline-drag-drop.ts
@@ -1,609 +1,609 @@
-import { useState, useCallback, type RefObject } from "react";
-import { useEditor } from "@/hooks/use-editor";
-import { processMediaAssets } from "@/lib/media/processing";
-import { toast } from "sonner";
-import { showMediaUploadToast } from "@/lib/media/upload-toast";
-import { TIMELINE_CONSTANTS } from "@/constants/timeline-constants";
-import { snapTimeToFrame } from "@/lib/time";
-import {
-	buildTextElement,
-	buildGraphicElement,
-	buildStickerElement,
-	buildElementFromMedia,
-	buildEffectElement,
-} from "@/lib/timeline/element-utils";
-import { AddTrackCommand, InsertElementCommand } from "@/lib/commands/timeline";
-import { BatchCommand } from "@/lib/commands";
-import { computeDropTarget } from "@/lib/timeline/drop-utils";
-import { getDragData, hasDragData } from "@/lib/drag-data";
-import { isMainTrack } from "@/lib/timeline/track-utils";
-import type { TrackType, DropTarget, ElementType } from "@/lib/timeline";
-import type {
-	MediaDragData,
-	GraphicDragData,
-	StickerDragData,
-	EffectDragData,
-} from "@/lib/timeline/drag";
-
-interface UseTimelineDragDropProps {
-	containerRef: RefObject<HTMLDivElement | null>;
-	headerRef?: RefObject<HTMLElement | null>;
-	tracksScrollRef?: RefObject<HTMLDivElement | null>;
-	zoomLevel: number;
-}
-
-export function useTimelineDragDrop({
-	containerRef,
-	headerRef,
-	tracksScrollRef,
-	zoomLevel,
-}: UseTimelineDragDropProps) {
-	const editor = useEditor();
-	const [isDragOver, setIsDragOver] = useState(false);
-	const [dropTarget, setDropTarget] = useState<DropTarget | null>(null);
-	const [dragElementType, setElementType] = useState<ElementType | null>(null);
-
-	const getSnappedTime = useCallback(
-		({ time }: { time: number }) => {
-			const projectFps = editor.project.getActive().settings.fps;
-			return snapTimeToFrame({ time, fps: projectFps });
-		},
-		[editor],
-	);
-
-	const getElementType = useCallback(
-		({ dataTransfer }: { dataTransfer: DataTransfer }): ElementType | null => {
-			const dragData = getDragData({ dataTransfer });
-			if (!dragData) return null;
-
-			if (dragData.type === "text") return "text";
-			if (dragData.type === "graphic") return "graphic";
-			if (dragData.type === "sticker") return "sticker";
-			if (dragData.type === "effect") return "effect";
-			if (dragData.type === "media") {
-				return dragData.mediaType;
-			}
-			return null;
-		},
-		[],
-	);
-
-	const getElementDuration = useCallback(
-		({
-			elementType,
-			mediaId,
-		}: {
-			elementType: ElementType;
-			mediaId?: string;
-		}): number => {
-			if (
-				elementType === "text" ||
-				elementType === "graphic" ||
-				elementType === "sticker" ||
-				elementType === "effect"
-			) {
-				return TIMELINE_CONSTANTS.DEFAULT_ELEMENT_DURATION;
-			}
-			if (mediaId) {
-				const mediaAssets = editor.media.getAssets();
-				const media = mediaAssets.find((m) => m.id === mediaId);
-				return media?.duration ?? TIMELINE_CONSTANTS.DEFAULT_ELEMENT_DURATION;
-			}
-			return TIMELINE_CONSTANTS.DEFAULT_ELEMENT_DURATION;
-		},
-		[editor],
-	);
-
-	const handleDragEnter = useCallback((e: React.DragEvent) => {
-		e.preventDefault();
-		const hasAsset = hasDragData({ dataTransfer: e.dataTransfer });
-		const hasFiles = e.dataTransfer.types.includes("Files");
-		if (!hasAsset && !hasFiles) return;
-		setIsDragOver(true);
-	}, []);
-
-	const handleDragOver = useCallback(
-		(e: React.DragEvent) => {
-			e.preventDefault();
-
-			const scrollContainer = tracksScrollRef?.current;
-			const referenceRect =
-				scrollContainer?.getBoundingClientRect() ??
-				containerRef.current?.getBoundingClientRect();
-			if (!referenceRect) return;
-
-			const headerHeight =
-				headerRef?.current?.getBoundingClientRect().height ?? 0;
-			const scrollLeft = scrollContainer?.scrollLeft ?? 0;
-			const scrollTop = scrollContainer?.scrollTop ?? 0;
-			const hasFiles = e.dataTransfer.types.includes("Files");
-			const isExternal =
-				hasFiles && !hasDragData({ dataTransfer: e.dataTransfer });
-
-			const elementType = getElementType({ dataTransfer: e.dataTransfer });
-
-			if (!elementType && hasFiles && isExternal) {
-				setDropTarget(null);
-				setElementType(null);
-				return;
-			}
-
-			if (!elementType) return;
-
-			setElementType(elementType);
-
-			const dragData = getDragData({ dataTransfer: e.dataTransfer });
-			const duration = getElementDuration({
-				elementType,
-				mediaId: dragData?.type === "media" ? dragData.id : undefined,
-			});
-
-			const mouseX = e.clientX - referenceRect.left + scrollLeft;
-			const mouseY = e.clientY - referenceRect.top + scrollTop - headerHeight;
-
-			const targetElementTypes =
-				dragData?.type === "effect"
-					? (dragData as EffectDragData).targetElementTypes
-					: dragData?.type === "media"
-						? (dragData as MediaDragData).targetElementTypes
-						: undefined;
-
-			const tracks = editor.timeline.getTracks();
-			const currentTime = editor.playback.getCurrentTime();
-			const target = computeDropTarget({
-				elementType,
-				mouseX,
-				mouseY,
-				tracks,
-				playheadTime: currentTime,
-				isExternalDrop: isExternal,
-				elementDuration: duration,
-				pixelsPerSecond: TIMELINE_CONSTANTS.PIXELS_PER_SECOND,
-				zoomLevel,
-				targetElementTypes,
-			});
-
-			target.xPosition = getSnappedTime({ time: target.xPosition });
-
-			setDropTarget(target);
-			e.dataTransfer.dropEffect = "copy";
-		},
-		[
-			containerRef,
-			headerRef,
-			tracksScrollRef,
-			zoomLevel,
-			getElementType,
-			getElementDuration,
-			getSnappedTime,
-			editor,
-		],
-	);
-
-	const handleDragLeave = useCallback(
-		(e: React.DragEvent) => {
-			e.preventDefault();
-			const rect = containerRef.current?.getBoundingClientRect();
-			if (rect) {
-				const { clientX, clientY } = e;
-				if (
-					clientX < rect.left ||
-					clientX > rect.right ||
-					clientY < rect.top ||
-					clientY > rect.bottom
-				) {
-					setIsDragOver(false);
-					setDropTarget(null);
-					setElementType(null);
-				}
-			}
-		},
-		[containerRef],
-	);
-
-	const executeTextDrop = useCallback(
-		({
-			target,
-			dragData,
-		}: {
-			target: DropTarget;
-			dragData: { name?: string; content?: string };
-		}) => {
-			const element = buildTextElement({
-				raw: {
-					name: dragData.name ?? "",
-					content: dragData.content ?? "",
-				},
-				startTime: target.xPosition,
-			});
-
-			if (target.isNewTrack) {
-				const addTrackCmd = new AddTrackCommand("text", target.trackIndex);
-				const insertCmd = new InsertElementCommand({
-					element,
-					placement: { mode: "explicit", trackId: addTrackCmd.getTrackId() },
-				});
-				editor.command.execute({
-					command: new BatchCommand([addTrackCmd, insertCmd]),
-				});
-				return;
-			}
-
-			const tracks = editor.timeline.getTracks();
-			const track = tracks[target.trackIndex];
-			if (!track) return;
-			editor.timeline.insertElement({
-				placement: { mode: "explicit", trackId: track.id },
-				element,
-			});
-		},
-		[editor],
-	);
-
-	const executeStickerDrop = useCallback(
-		({
-			target,
-			dragData,
-		}: {
-			target: DropTarget;
-			dragData: StickerDragData;
-		}) => {
-			const element = buildStickerElement({
-				stickerId: dragData.stickerId,
-				name: dragData.name,
-				startTime: target.xPosition,
-			});
-
-			if (target.isNewTrack) {
-				const addTrackCmd = new AddTrackCommand("graphic", target.trackIndex);
-				const insertCmd = new InsertElementCommand({
-					element,
-					placement: { mode: "explicit", trackId: addTrackCmd.getTrackId() },
-				});
-				editor.command.execute({
-					command: new BatchCommand([addTrackCmd, insertCmd]),
-				});
-				return;
-			}
-
-			const tracks = editor.timeline.getTracks();
-			const track = tracks[target.trackIndex];
-			if (!track) return;
-			editor.timeline.insertElement({
-				placement: { mode: "explicit", trackId: track.id },
-				element,
-			});
-		},
-		[editor],
-	);
-
-	const executeGraphicDrop = useCallback(
-		({
-			target,
-			dragData,
-		}: {
-			target: DropTarget;
-			dragData: GraphicDragData;
-		}) => {
-			const element = buildGraphicElement({
-				definitionId: dragData.definitionId,
-				name: dragData.name,
-				startTime: target.xPosition,
-				params: dragData.params,
-			});
-
-			if (target.isNewTrack) {
-				const addTrackCmd = new AddTrackCommand("graphic", target.trackIndex);
-				const insertCmd = new InsertElementCommand({
-					element,
-					placement: { mode: "explicit", trackId: addTrackCmd.getTrackId() },
-				});
-				editor.command.execute({
-					command: new BatchCommand([addTrackCmd, insertCmd]),
-				});
-				return;
-			}
-
-			const tracks = editor.timeline.getTracks();
-			const track = tracks[target.trackIndex];
-			if (!track) return;
-			editor.timeline.insertElement({
-				placement: { mode: "explicit", trackId: track.id },
-				element,
-			});
-		},
-		[editor],
-	);
-
-	const executeMediaDrop = useCallback(
-		({ target, dragData }: { target: DropTarget; dragData: MediaDragData }) => {
-			if (target.targetElement) {
-				toast.info("Replace media source is coming soon!");
-				return;
-			}
-
-			const mediaAssets = editor.media.getAssets();
-			const mediaAsset = mediaAssets.find((m) => m.id === dragData.id);
-			if (!mediaAsset) return;
-
-			const trackType: TrackType =
-				dragData.mediaType === "audio" ? "audio" : "video";
-
-			const duration =
-				mediaAsset.duration ?? TIMELINE_CONSTANTS.DEFAULT_ELEMENT_DURATION;
-			const element = buildElementFromMedia({
-				mediaId: mediaAsset.id,
-				mediaType: mediaAsset.type,
-				name: mediaAsset.name,
-				duration,
-				startTime: target.xPosition,
-			});
-
-			if (target.isNewTrack) {
-				const addTrackCmd = new AddTrackCommand(trackType, target.trackIndex);
-				const insertCmd = new InsertElementCommand({
-					element,
-					placement: { mode: "explicit", trackId: addTrackCmd.getTrackId() },
-				});
-				editor.command.execute({
-					command: new BatchCommand([addTrackCmd, insertCmd]),
-				});
-				return;
-			}
-
-			const tracks = editor.timeline.getTracks();
-			const track = tracks[target.trackIndex];
-			if (!track) return;
-			editor.timeline.insertElement({
-				placement: { mode: "explicit", trackId: track.id },
-				element,
-			});
-		},
-		[editor],
-	);
-
-	const executeEffectDrop = useCallback(
-		({
-			target,
-			dragData,
-		}: {
-			target: DropTarget;
-			dragData: EffectDragData;
-		}) => {
-			if (target.targetElement) {
-				editor.timeline.addClipEffect({
-					trackId: target.targetElement.trackId,
-					elementId: target.targetElement.elementId,
-					effectType: dragData.effectType,
-				});
-				return;
-			}
-
-			const tracks = editor.timeline.getTracks();
-			const effectTrack = tracks.find((t) => t.type === "effect");
-			let trackId: string;
-
-			if (effectTrack) {
-				trackId = effectTrack.id;
-			} else if (target.isNewTrack) {
-				const addTrackCmd = new AddTrackCommand("effect", target.trackIndex);
-				const insertCmd = new InsertElementCommand({
-					element: buildEffectElement({
-						effectType: dragData.effectType,
-						startTime: target.xPosition,
-					}),
-					placement: { mode: "explicit", trackId: addTrackCmd.getTrackId() },
-				});
-				editor.command.execute({
-					command: new BatchCommand([addTrackCmd, insertCmd]),
-				});
-				return;
-			} else {
-				const track = tracks[target.trackIndex];
-				if (!track || track.type !== "effect") return;
-				trackId = track.id;
-			}
-
-			const element = buildEffectElement({
-				effectType: dragData.effectType,
-				startTime: target.xPosition,
-			});
-
-			editor.timeline.insertElement({
-				placement: { mode: "explicit", trackId },
-				element,
-			});
-		},
-		[editor],
-	);
-
-	const executeFileDrop = useCallback(
-		async ({
-			files,
-			mouseX,
-			mouseY,
-		}: {
-			files: File[];
-			mouseX: number;
-			mouseY: number;
-		}) => {
-			const activeProject = editor.project.getActiveOrNull();
-			if (!activeProject) return;
-
-			await showMediaUploadToast({
-				filesCount: files.length,
-				promise: async () => {
-					const processedAssets = await processMediaAssets({ files });
-					const projectId = activeProject.metadata.id;
-
-					for (const asset of processedAssets) {
-						const createdAsset = await editor.media.addMediaAsset({
-							projectId,
-							asset,
-						});
-						if (!createdAsset) continue;
-
-						const duration =
-							createdAsset.duration ?? TIMELINE_CONSTANTS.DEFAULT_ELEMENT_DURATION;
-						const currentTracks = editor.timeline.getTracks();
-						const currentTime = editor.playback.getCurrentTime();
-						const onlyTrack = currentTracks[0];
-						const reuseMainTrackId =
-							createdAsset.type !== "audio" &&
-							currentTracks.length === 1 &&
-							!!onlyTrack &&
-							isMainTrack(onlyTrack) &&
-							onlyTrack.elements.length === 0
-								? onlyTrack.id
-								: null;
-						const dropTarget = reuseMainTrackId
-							? null
-							: computeDropTarget({
-									elementType: createdAsset.type,
-									mouseX,
-									mouseY,
-									tracks: currentTracks,
-									playheadTime: currentTime,
-									isExternalDrop: true,
-									elementDuration: duration,
-									pixelsPerSecond: TIMELINE_CONSTANTS.PIXELS_PER_SECOND,
-									zoomLevel,
-								});
-
-						const trackType: TrackType =
-							createdAsset.type === "audio" ? "audio" : "video";
-
-						let trackId: string | undefined;
-						if (reuseMainTrackId) {
-							trackId = reuseMainTrackId;
-						} else {
-							if (!dropTarget) continue;
-							if (dropTarget.isNewTrack) {
-								const addTrackCmd = new AddTrackCommand(
-									trackType,
-									dropTarget.trackIndex,
-								);
-								trackId = addTrackCmd.getTrackId();
-								editor.command.execute({ command: addTrackCmd });
-							} else {
-								trackId = currentTracks[dropTarget.trackIndex]?.id;
-							}
-						}
-
-						if (!trackId) continue;
-
-						const element = buildElementFromMedia({
-							mediaId: createdAsset.id,
-							mediaType: createdAsset.type,
-							name: createdAsset.name,
-							duration,
-							startTime: dropTarget?.xPosition ?? currentTime,
-							buffer:
-								createdAsset.type === "audio"
-									? new AudioBuffer({ length: 1, sampleRate: 44100 })
-									: undefined,
-						});
-
-						const insertCmd = new InsertElementCommand({
-							element,
-							placement: { mode: "explicit", trackId },
-						});
-						editor.command.execute({ command: insertCmd });
-					}
-
-					return {
-						uploadedCount: processedAssets.length,
-						assetNames: processedAssets.map((asset) => asset.name),
-					};
-				},
-			});
-		},
-		[editor, zoomLevel],
-	);
-
-	const handleDrop = useCallback(
-		async (e: React.DragEvent) => {
-			e.preventDefault();
-
-			const hasAsset = hasDragData({ dataTransfer: e.dataTransfer });
-			const hasFiles = e.dataTransfer.files?.length > 0;
-
-			if (!hasAsset && !hasFiles) return;
-
-			const currentTarget = dropTarget;
-			setIsDragOver(false);
-			setDropTarget(null);
-			setElementType(null);
-
-			try {
-				if (hasAsset) {
-					if (!currentTarget) return;
-					const dragData = getDragData({ dataTransfer: e.dataTransfer });
-					if (!dragData) return;
-
-					if (dragData.type === "text") {
-						executeTextDrop({ target: currentTarget, dragData });
-					} else if (dragData.type === "graphic") {
-						executeGraphicDrop({
-							target: currentTarget,
-							dragData: dragData as GraphicDragData,
-						});
-					} else if (dragData.type === "sticker") {
-						executeStickerDrop({ target: currentTarget, dragData });
-					} else if (dragData.type === "effect") {
-						executeEffectDrop({
-							target: currentTarget,
-							dragData: dragData as EffectDragData,
-						});
-					} else {
-						executeMediaDrop({ target: currentTarget, dragData });
-					}
-				} else if (hasFiles) {
-					const scrollContainer = tracksScrollRef?.current;
-					const referenceRect =
-						scrollContainer?.getBoundingClientRect() ??
-						containerRef.current?.getBoundingClientRect();
-					if (!referenceRect) return;
-					const scrollLeft = scrollContainer?.scrollLeft ?? 0;
-					const scrollTop = scrollContainer?.scrollTop ?? 0;
-					const mouseX = e.clientX - referenceRect.left + scrollLeft;
-					const headerHeight =
-						headerRef?.current?.getBoundingClientRect().height ?? 0;
-					const mouseY =
-						e.clientY - referenceRect.top + scrollTop - headerHeight;
-					await executeFileDrop({
-						files: Array.from(e.dataTransfer.files),
-						mouseX,
-						mouseY,
-					});
-				}
-			} catch (err) {
-				console.error("Failed to process drop:", err);
-			}
-		},
-		[
-			dropTarget,
-			executeTextDrop,
-			executeGraphicDrop,
-			executeStickerDrop,
-			executeMediaDrop,
-			executeEffectDrop,
-			executeFileDrop,
-			containerRef,
-			headerRef,
-			tracksScrollRef,
-		],
-	);
-
-	return {
-		isDragOver,
-		dropTarget,
-		dragElementType,
-		dragProps: {
-			onDragEnter: handleDragEnter,
-			onDragOver: handleDragOver,
-			onDragLeave: handleDragLeave,
-			onDrop: handleDrop,
-		},
-	};
-}
+import { useState, useCallback, type RefObject } from "react";
+import { useEditor } from "@/hooks/use-editor";
+import { processMediaAssets } from "@/lib/media/processing";
+import { toast } from "sonner";
+import { showMediaUploadToast } from "@/lib/media/upload-toast";
+import { TIMELINE_CONSTANTS } from "@/constants/timeline-constants";
+import { snapTimeToFrame } from "opencut-wasm";
+import {
+	buildTextElement,
+	buildGraphicElement,
+	buildStickerElement,
+	buildElementFromMedia,
+	buildEffectElement,
+} from "@/lib/timeline/element-utils";
+import { AddTrackCommand, InsertElementCommand } from "@/lib/commands/timeline";
+import { BatchCommand } from "@/lib/commands";
+import { computeDropTarget } from "@/lib/timeline/drop-utils";
+import { getDragData, hasDragData } from "@/lib/drag-data";
+import { isMainTrack } from "@/lib/timeline/track-utils";
+import type { TrackType, DropTarget, ElementType } from "@/lib/timeline";
+import type {
+	MediaDragData,
+	GraphicDragData,
+	StickerDragData,
+	EffectDragData,
+} from "@/lib/timeline/drag";
+
+interface UseTimelineDragDropProps {
+	containerRef: RefObject<HTMLDivElement | null>;
+	headerRef?: RefObject<HTMLElement | null>;
+	tracksScrollRef?: RefObject<HTMLDivElement | null>;
+	zoomLevel: number;
+}
+
+export function useTimelineDragDrop({
+	containerRef,
+	headerRef,
+	tracksScrollRef,
+	zoomLevel,
+}: UseTimelineDragDropProps) {
+	const editor = useEditor();
+	const [isDragOver, setIsDragOver] = useState(false);
+	const [dropTarget, setDropTarget] = useState<DropTarget | null>(null);
+	const [dragElementType, setElementType] = useState<ElementType | null>(null);
+
+	const getSnappedTime = useCallback(
+		({ time }: { time: number }) => {
+			const projectFps = editor.project.getActive().settings.fps;
+			return snapTimeToFrame({ time, fps: projectFps });
+		},
+		[editor],
+	);
+
+	const getElementType = useCallback(
+		({ dataTransfer }: { dataTransfer: DataTransfer }): ElementType | null => {
+			const dragData = getDragData({ dataTransfer });
+			if (!dragData) return null;
+
+			if (dragData.type === "text") return "text";
+			if (dragData.type === "graphic") return "graphic";
+			if (dragData.type === "sticker") return "sticker";
+			if (dragData.type === "effect") return "effect";
+			if (dragData.type === "media") {
+				return dragData.mediaType;
+			}
+			return null;
+		},
+		[],
+	);
+
+	const getElementDuration = useCallback(
+		({
+			elementType,
+			mediaId,
+		}: {
+			elementType: ElementType;
+			mediaId?: string;
+		}): number => {
+			if (
+				elementType === "text" ||
+				elementType === "graphic" ||
+				elementType === "sticker" ||
+				elementType === "effect"
+			) {
+				return TIMELINE_CONSTANTS.DEFAULT_ELEMENT_DURATION;
+			}
+			if (mediaId) {
+				const mediaAssets = editor.media.getAssets();
+				const media = mediaAssets.find((m) => m.id === mediaId);
+				return media?.duration ?? TIMELINE_CONSTANTS.DEFAULT_ELEMENT_DURATION;
+			}
+			return TIMELINE_CONSTANTS.DEFAULT_ELEMENT_DURATION;
+		},
+		[editor],
+	);
+
+	const handleDragEnter = useCallback((e: React.DragEvent) => {
+		e.preventDefault();
+		const hasAsset = hasDragData({ dataTransfer: e.dataTransfer });
+		const hasFiles = e.dataTransfer.types.includes("Files");
+		if (!hasAsset && !hasFiles) return;
+		setIsDragOver(true);
+	}, []);
+
+	const handleDragOver = useCallback(
+		(e: React.DragEvent) => {
+			e.preventDefault();
+
+			const scrollContainer = tracksScrollRef?.current;
+			const referenceRect =
+				scrollContainer?.getBoundingClientRect() ??
+				containerRef.current?.getBoundingClientRect();
+			if (!referenceRect) return;
+
+			const headerHeight =
+				headerRef?.current?.getBoundingClientRect().height ?? 0;
+			const scrollLeft = scrollContainer?.scrollLeft ?? 0;
+			const scrollTop = scrollContainer?.scrollTop ?? 0;
+			const hasFiles = e.dataTransfer.types.includes("Files");
+			const isExternal =
+				hasFiles && !hasDragData({ dataTransfer: e.dataTransfer });
+
+			const elementType = getElementType({ dataTransfer: e.dataTransfer });
+
+			if (!elementType && hasFiles && isExternal) {
+				setDropTarget(null);
+				setElementType(null);
+				return;
+			}
+
+			if (!elementType) return;
+
+			setElementType(elementType);
+
+			const dragData = getDragData({ dataTransfer: e.dataTransfer });
+			const duration = getElementDuration({
+				elementType,
+				mediaId: dragData?.type === "media" ? dragData.id : undefined,
+			});
+
+			const mouseX = e.clientX - referenceRect.left + scrollLeft;
+			const mouseY = e.clientY - referenceRect.top + scrollTop - headerHeight;
+
+			const targetElementTypes =
+				dragData?.type === "effect"
+					? (dragData as EffectDragData).targetElementTypes
+					: dragData?.type === "media"
+						? (dragData as MediaDragData).targetElementTypes
+						: undefined;
+
+			const tracks = editor.timeline.getTracks();
+			const currentTime = editor.playback.getCurrentTime();
+			const target = computeDropTarget({
+				elementType,
+				mouseX,
+				mouseY,
+				tracks,
+				playheadTime: currentTime,
+				isExternalDrop: isExternal,
+				elementDuration: duration,
+				pixelsPerSecond: TIMELINE_CONSTANTS.PIXELS_PER_SECOND,
+				zoomLevel,
+				targetElementTypes,
+			});
+
+			target.xPosition = getSnappedTime({ time: target.xPosition });
+
+			setDropTarget(target);
+			e.dataTransfer.dropEffect = "copy";
+		},
+		[
+			containerRef,
+			headerRef,
+			tracksScrollRef,
+			zoomLevel,
+			getElementType,
+			getElementDuration,
+			getSnappedTime,
+			editor,
+		],
+	);
+
+	const handleDragLeave = useCallback(
+		(e: React.DragEvent) => {
+			e.preventDefault();
+			const rect = containerRef.current?.getBoundingClientRect();
+			if (rect) {
+				const { clientX, clientY } = e;
+				if (
+					clientX < rect.left ||
+					clientX > rect.right ||
+					clientY < rect.top ||
+					clientY > rect.bottom
+				) {
+					setIsDragOver(false);
+					setDropTarget(null);
+					setElementType(null);
+				}
+			}
+		},
+		[containerRef],
+	);
+
+	const executeTextDrop = useCallback(
+		({
+			target,
+			dragData,
+		}: {
+			target: DropTarget;
+			dragData: { name?: string; content?: string };
+		}) => {
+			const element = buildTextElement({
+				raw: {
+					name: dragData.name ?? "",
+					content: dragData.content ?? "",
+				},
+				startTime: target.xPosition,
+			});
+
+			if (target.isNewTrack) {
+				const addTrackCmd = new AddTrackCommand("text", target.trackIndex);
+				const insertCmd = new InsertElementCommand({
+					element,
+					placement: { mode: "explicit", trackId: addTrackCmd.getTrackId() },
+				});
+				editor.command.execute({
+					command: new BatchCommand([addTrackCmd, insertCmd]),
+				});
+				return;
+			}
+
+			const tracks = editor.timeline.getTracks();
+			const track = tracks[target.trackIndex];
+			if (!track) return;
+			editor.timeline.insertElement({
+				placement: { mode: "explicit", trackId: track.id },
+				element,
+			});
+		},
+		[editor],
+	);
+
+	const executeStickerDrop = useCallback(
+		({
+			target,
+			dragData,
+		}: {
+			target: DropTarget;
+			dragData: StickerDragData;
+		}) => {
+			const element = buildStickerElement({
+				stickerId: dragData.stickerId,
+				name: dragData.name,
+				startTime: target.xPosition,
+			});
+
+			if (target.isNewTrack) {
+				const addTrackCmd = new AddTrackCommand("graphic", target.trackIndex);
+				const insertCmd = new InsertElementCommand({
+					element,
+					placement: { mode: "explicit", trackId: addTrackCmd.getTrackId() },
+				});
+				editor.command.execute({
+					command: new BatchCommand([addTrackCmd, insertCmd]),
+				});
+				return;
+			}
+
+			const tracks = editor.timeline.getTracks();
+			const track = tracks[target.trackIndex];
+			if (!track) return;
+			editor.timeline.insertElement({
+				placement: { mode: "explicit", trackId: track.id },
+				element,
+			});
+		},
+		[editor],
+	);
+
+	const executeGraphicDrop = useCallback(
+		({
+			target,
+			dragData,
+		}: {
+			target: DropTarget;
+			dragData: GraphicDragData;
+		}) => {
+			const element = buildGraphicElement({
+				definitionId: dragData.definitionId,
+				name: dragData.name,
+				startTime: target.xPosition,
+				params: dragData.params,
+			});
+
+			if (target.isNewTrack) {
+				const addTrackCmd = new AddTrackCommand("graphic", target.trackIndex);
+				const insertCmd = new InsertElementCommand({
+					element,
+					placement: { mode: "explicit", trackId: addTrackCmd.getTrackId() },
+				});
+				editor.command.execute({
+					command: new BatchCommand([addTrackCmd, insertCmd]),
+				});
+				return;
+			}
+
+			const tracks = editor.timeline.getTracks();
+			const track = tracks[target.trackIndex];
+			if (!track) return;
+			editor.timeline.insertElement({
+				placement: { mode: "explicit", trackId: track.id },
+				element,
+			});
+		},
+		[editor],
+	);
+
+	const executeMediaDrop = useCallback(
+		({ target, dragData }: { target: DropTarget; dragData: MediaDragData }) => {
+			if (target.targetElement) {
+				toast.info("Replace media source is coming soon!");
+				return;
+			}
+
+			const mediaAssets = editor.media.getAssets();
+			const mediaAsset = mediaAssets.find((m) => m.id === dragData.id);
+			if (!mediaAsset) return;
+
+			const trackType: TrackType =
+				dragData.mediaType === "audio" ? "audio" : "video";
+
+			const duration =
+				mediaAsset.duration ?? TIMELINE_CONSTANTS.DEFAULT_ELEMENT_DURATION;
+			const element = buildElementFromMedia({
+				mediaId: mediaAsset.id,
+				mediaType: mediaAsset.type,
+				name: mediaAsset.name,
+				duration,
+				startTime: target.xPosition,
+			});
+
+			if (target.isNewTrack) {
+				const addTrackCmd = new AddTrackCommand(trackType, target.trackIndex);
+				const insertCmd = new InsertElementCommand({
+					element,
+					placement: { mode: "explicit", trackId: addTrackCmd.getTrackId() },
+				});
+				editor.command.execute({
+					command: new BatchCommand([addTrackCmd, insertCmd]),
+				});
+				return;
+			}
+
+			const tracks = editor.timeline.getTracks();
+			const track = tracks[target.trackIndex];
+			if (!track) return;
+			editor.timeline.insertElement({
+				placement: { mode: "explicit", trackId: track.id },
+				element,
+			});
+		},
+		[editor],
+	);
+
+	const executeEffectDrop = useCallback(
+		({
+			target,
+			dragData,
+		}: {
+			target: DropTarget;
+			dragData: EffectDragData;
+		}) => {
+			if (target.targetElement) {
+				editor.timeline.addClipEffect({
+					trackId: target.targetElement.trackId,
+					elementId: target.targetElement.elementId,
+					effectType: dragData.effectType,
+				});
+				return;
+			}
+
+			const tracks = editor.timeline.getTracks();
+			const effectTrack = tracks.find((t) => t.type === "effect");
+			let trackId: string;
+
+			if (effectTrack) {
+				trackId = effectTrack.id;
+			} else if (target.isNewTrack) {
+				const addTrackCmd = new AddTrackCommand("effect", target.trackIndex);
+				const insertCmd = new InsertElementCommand({
+					element: buildEffectElement({
+						effectType: dragData.effectType,
+						startTime: target.xPosition,
+					}),
+					placement: { mode: "explicit", trackId: addTrackCmd.getTrackId() },
+				});
+				editor.command.execute({
+					command: new BatchCommand([addTrackCmd, insertCmd]),
+				});
+				return;
+			} else {
+				const track = tracks[target.trackIndex];
+				if (!track || track.type !== "effect") return;
+				trackId = track.id;
+			}
+
+			const element = buildEffectElement({
+				effectType: dragData.effectType,
+				startTime: target.xPosition,
+			});
+
+			editor.timeline.insertElement({
+				placement: { mode: "explicit", trackId },
+				element,
+			});
+		},
+		[editor],
+	);
+
+	const executeFileDrop = useCallback(
+		async ({
+			files,
+			mouseX,
+			mouseY,
+		}: {
+			files: File[];
+			mouseX: number;
+			mouseY: number;
+		}) => {
+			const activeProject = editor.project.getActiveOrNull();
+			if (!activeProject) return;
+
+			await showMediaUploadToast({
+				filesCount: files.length,
+				promise: async () => {
+					const processedAssets = await processMediaAssets({ files });
+					const projectId = activeProject.metadata.id;
+
+					for (const asset of processedAssets) {
+						const createdAsset = await editor.media.addMediaAsset({
+							projectId,
+							asset,
+						});
+						if (!createdAsset) continue;
+
+						const duration =
+							createdAsset.duration ?? TIMELINE_CONSTANTS.DEFAULT_ELEMENT_DURATION;
+						const currentTracks = editor.timeline.getTracks();
+						const currentTime = editor.playback.getCurrentTime();
+						const onlyTrack = currentTracks[0];
+						const reuseMainTrackId =
+							createdAsset.type !== "audio" &&
+							currentTracks.length === 1 &&
+							!!onlyTrack &&
+							isMainTrack(onlyTrack) &&
+							onlyTrack.elements.length === 0
+								? onlyTrack.id
+								: null;
+						const dropTarget = reuseMainTrackId
+							? null
+							: computeDropTarget({
+									elementType: createdAsset.type,
+									mouseX,
+									mouseY,
+									tracks: currentTracks,
+									playheadTime: currentTime,
+									isExternalDrop: true,
+									elementDuration: duration,
+									pixelsPerSecond: TIMELINE_CONSTANTS.PIXELS_PER_SECOND,
+									zoomLevel,
+								});
+
+						const trackType: TrackType =
+							createdAsset.type === "audio" ? "audio" : "video";
+
+						let trackId: string | undefined;
+						if (reuseMainTrackId) {
+							trackId = reuseMainTrackId;
+						} else {
+							if (!dropTarget) continue;
+							if (dropTarget.isNewTrack) {
+								const addTrackCmd = new AddTrackCommand(
+									trackType,
+									dropTarget.trackIndex,
+								);
+								trackId = addTrackCmd.getTrackId();
+								editor.command.execute({ command: addTrackCmd });
+							} else {
+								trackId = currentTracks[dropTarget.trackIndex]?.id;
+							}
+						}
+
+						if (!trackId) continue;
+
+						const element = buildElementFromMedia({
+							mediaId: createdAsset.id,
+							mediaType: createdAsset.type,
+							name: createdAsset.name,
+							duration,
+							startTime: dropTarget?.xPosition ?? currentTime,
+							buffer:
+								createdAsset.type === "audio"
+									? new AudioBuffer({ length: 1, sampleRate: 44100 })
+									: undefined,
+						});
+
+						const insertCmd = new InsertElementCommand({
+							element,
+							placement: { mode: "explicit", trackId },
+						});
+						editor.command.execute({ command: insertCmd });
+					}
+
+					return {
+						uploadedCount: processedAssets.length,
+						assetNames: processedAssets.map((asset) => asset.name),
+					};
+				},
+			});
+		},
+		[editor, zoomLevel],
+	);
+
+	const handleDrop = useCallback(
+		async (e: React.DragEvent) => {
+			e.preventDefault();
+
+			const hasAsset = hasDragData({ dataTransfer: e.dataTransfer });
+			const hasFiles = e.dataTransfer.files?.length > 0;
+
+			if (!hasAsset && !hasFiles) return;
+
+			const currentTarget = dropTarget;
+			setIsDragOver(false);
+			setDropTarget(null);
+			setElementType(null);
+
+			try {
+				if (hasAsset) {
+					if (!currentTarget) return;
+					const dragData = getDragData({ dataTransfer: e.dataTransfer });
+					if (!dragData) return;
+
+					if (dragData.type === "text") {
+						executeTextDrop({ target: currentTarget, dragData });
+					} else if (dragData.type === "graphic") {
+						executeGraphicDrop({
+							target: currentTarget,
+							dragData: dragData as GraphicDragData,
+						});
+					} else if (dragData.type === "sticker") {
+						executeStickerDrop({ target: currentTarget, dragData });
+					} else if (dragData.type === "effect") {
+						executeEffectDrop({
+							target: currentTarget,
+							dragData: dragData as EffectDragData,
+						});
+					} else {
+						executeMediaDrop({ target: currentTarget, dragData });
+					}
+				} else if (hasFiles) {
+					const scrollContainer = tracksScrollRef?.current;
+					const referenceRect =
+						scrollContainer?.getBoundingClientRect() ??
+						containerRef.current?.getBoundingClientRect();
+					if (!referenceRect) return;
+					const scrollLeft = scrollContainer?.scrollLeft ?? 0;
+					const scrollTop = scrollContainer?.scrollTop ?? 0;
+					const mouseX = e.clientX - referenceRect.left + scrollLeft;
+					const headerHeight =
+						headerRef?.current?.getBoundingClientRect().height ?? 0;
+					const mouseY =
+						e.clientY - referenceRect.top + scrollTop - headerHeight;
+					await executeFileDrop({
+						files: Array.from(e.dataTransfer.files),
+						mouseX,
+						mouseY,
+					});
+				}
+			} catch (err) {
+				console.error("Failed to process drop:", err);
+			}
+		},
+		[
+			dropTarget,
+			executeTextDrop,
+			executeGraphicDrop,
+			executeStickerDrop,
+			executeMediaDrop,
+			executeEffectDrop,
+			executeFileDrop,
+			containerRef,
+			headerRef,
+			tracksScrollRef,
+		],
+	);
+
+	return {
+		isDragOver,
+		dropTarget,
+		dragElementType,
+		dragProps: {
+			onDragEnter: handleDragEnter,
+			onDragOver: handleDragOver,
+			onDragLeave: handleDragLeave,
+			onDrop: handleDrop,
+		},
+	};
+}