OpenCut/apps/web/src/lib/timeline/placement/main-track.ts

97 lines
1.9 KiB
TypeScript

import type { TimelineElement, TimelineTrack, VideoTrack } from "@/lib/timeline";
import { generateUUID } from "@/utils/id";
const MAIN_TRACK_NAME = "Main Track";
export function isMainTrack(track: TimelineTrack): track is VideoTrack {
return track.type === "video" && track.isMain === true;
}
export function getMainTrack({
tracks,
}: {
tracks: TimelineTrack[];
}): VideoTrack | null {
return tracks.find((track) => isMainTrack(track)) ?? null;
}
export function ensureMainTrack({
tracks,
}: {
tracks: TimelineTrack[];
}): TimelineTrack[] {
if (tracks.some((track) => isMainTrack(track))) {
return tracks;
}
return [
{
id: generateUUID(),
name: MAIN_TRACK_NAME,
type: "video",
elements: [],
muted: false,
isMain: true,
hidden: false,
},
...tracks,
];
}
export function getEarliestMainTrackElement({
tracks,
excludeElementId,
}: {
tracks: TimelineTrack[];
excludeElementId?: string;
}): TimelineElement | null {
const mainTrack = getMainTrack({ tracks });
if (!mainTrack) {
return null;
}
const elements = mainTrack.elements.filter((element) => {
return !excludeElementId || element.id !== excludeElementId;
});
if (elements.length === 0) {
return null;
}
return elements.reduce((earliestElement, element) => {
return element.startTime < earliestElement.startTime
? element
: earliestElement;
});
}
export function enforceMainTrackStart({
tracks,
targetTrackId,
requestedStartTime,
excludeElementId,
}: {
tracks: TimelineTrack[];
targetTrackId: string;
requestedStartTime: number;
excludeElementId?: string;
}): number {
const mainTrack = getMainTrack({ tracks });
if (!mainTrack || mainTrack.id !== targetTrackId) {
return requestedStartTime;
}
const earliestElement = getEarliestMainTrackElement({
tracks,
excludeElementId,
});
if (!earliestElement) {
return 0;
}
if (requestedStartTime <= earliestElement.startTime) {
return 0;
}
return requestedStartTime;
}