const minute = 60;
const hour = minute * 60;
const day = hour * 24;
const week = day * 7;
const year = day * 365.25;
const REGEX = /^(\d+|\d+\.\d+) ?(seconds?|secs?|s|minutes?|mins?|m|hours?|hrs?|h|days?|d|weeks?|w|years?|yrs?|y)$/i;
export default (str) => {
    const matched = REGEX.exec(str);
    if (!matched) {
        throw new TypeError('Invalid time period format');
    }
    const value = parseFloat(matched[1]);
    const unit = matched[2].toLowerCase();
    switch (unit) {
        case 'sec':
        case 'secs':
        case 'second':
        case 'seconds':
        case 's':
            return Math.round(value);
        case 'minute':
        case 'minutes':
        case 'min':
        case 'mins':
        case 'm':
            return Math.round(value * minute);
        case 'hour':
        case 'hours':
        case 'hr':
        case 'hrs':
        case 'h':
            return Math.round(value * hour);
        case 'day':
        case 'days':
        case 'd':
            return Math.round(value * day);
        case 'week':
        case 'weeks':
        case 'w':
            return Math.round(value * week);
        default:
            return Math.round(value * year);
    }
};