codebase overhaul (#697)

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

@@ -0,0 +1,53 @@
+import { Command } from "@/lib/commands/base-command";
+import type { TrackType, TimelineTrack } from "@/types/timeline";
+import { generateUUID } from "@/utils/id";
+import { EditorCore } from "@/core";
+import {
+	buildEmptyTrack,
+	getDefaultInsertIndexForTrack,
+} from "@/lib/timeline/track-utils";
+
+export class AddTrackCommand extends Command {
+	private trackId: string;
+	private savedState: TimelineTrack[] | null = null;
+
+	constructor(
+		private type: TrackType,
+		private index?: number,
+	) {
+		super();
+		this.trackId = generateUUID();
+	}
+
+	execute(): void {
+		const editor = EditorCore.getInstance();
+		this.savedState = editor.timeline.getTracks();
+
+		const newTrack: TimelineTrack = buildEmptyTrack({
+			id: this.trackId,
+			type: this.type,
+		});
+
+		const updatedTracks = [...(this.savedState || [])];
+		const insertIndex =
+			this.index ??
+			getDefaultInsertIndexForTrack({
+				tracks: updatedTracks,
+				trackType: this.type,
+			});
+		updatedTracks.splice(insertIndex, 0, newTrack);
+
+		editor.timeline.updateTracks(updatedTracks);
+	}
+
+	undo(): void {
+		if (this.savedState) {
+			const editor = EditorCore.getInstance();
+			editor.timeline.updateTracks(this.savedState);
+		}
+	}
+
+	getTrackId(): string {
+		return this.trackId;
+	}
+}