media-transcript/src/util.js

A web component for an interactive transcript built from WebVTT cues.

export const generateId = (namespace) => `${namespace}-${
	// append a 6-digit 24-bit number
	Math.floor((1 + Math.random()) * 0x1000000).toString(24)
}`;

export const inCue = (cue, time) => cue.startTime <= time && cue.endTime > time;

export const formatTimeDefault = (timeInSeconds, formatStr = 'mm:ss') => {
	const date = new Date(0, 0);
	date.setSeconds(timeInSeconds);
	const strFormat = formatStr.split(':').map((token) => {
		const t = token.toLowerCase();
		let val;
		if (t.includes('h')) val = date.getHours();
		if (t.includes('m')) val = date.getMinutes();
		if (t.includes('s')) val = date.getSeconds();
		val = val.toString();
		if (t.length > 1) {
			val = val.padStart(2, '0');
		}
		return val;
	});
	return strFormat.join(':');
};

export const timeStrToNumber = (timeStr) => {
	if (typeof timeStr === 'number') return timeStr;
	const timeArr = timeStr.split(':');
	let h = '0';
	let m = '0';
	let s = '0';
	switch (timeArr.length) {
	case 3:
		[h, m, s] = timeArr;
		break;
	case 2:
		[m, s] = timeArr;
		break;
	case 1:
		return Number(timeArr[0].replace(',', '.'));
	default:
		throw new Error('time strings must be in the format hh:mm:ss');
	}
	return parseInt(h, 10) * 60 * 60
		+ parseInt(m, 10) * 60
		+ Number(s.replace(',', '.'));
};

export function hasAttributeToken(attr, ...tokens) {
	return (this.getAttribute(attr) || '')
		.split(/\s/g)
		.some((v) => tokens.some((t) => t === v));
}

export const debug = ({ name, message }) => {
	console.debug(`[${name}]:`, message);	// eslint-disable-line no-console
};

export const TranscriptConfig = {
	focusClass: 'focused',
	namespace: 'mt',
};