Bilibili Timeline Timezone Fix

timezone.js

let timezoneOffset = 8 * 60; // in minutes

function timeshift(date) {
    return new Date(+date + timezoneOffset * 60000);
}

// Seconds and Milliseconds are always same as timezone offset is always multiple of 0.5
for (let name of ['Date', 'Day', 'FullYear', 'Hours', 'Minutes', 'Month']) {
    Date.prototype['get' + name] = function () {
        return timeshift(this)['getUTC' + name]();
    }

    if (name === 'Day') continue;
    Date.prototype['set' + name] = function (arg) {
        let date = timeshift(this);
        date['setUTC' + name](arg);
        this.setTime(+date - timezoneOffset * 60000);
    }
}

Date.prototype.getTimezoneOffset = function () {
    return -timezoneOffset;
}