// ==UserScript==
// @name         2p2-Scrollback-after-tweets
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  Scroll back to the correct anchor tag after tweets load and screw up the scroll position
// @author       suzzer99
// @match        https://forumserver.twoplustwo.com/*index*.html
// @grant        none
// ==/UserScript==

function scrollTo (position, duration) {
    // cancel if already on top
    if (document.scrollingElement.scrollTop === position) return;

    const totalScrollDistance = document.scrollingElement.scrollTop;
    let scrollY = totalScrollDistance, oldTimestamp = null;

    function step (newTimestamp) {
        if (oldTimestamp !== null) {
            // if duration is 0 scrollY will be -Infinity
            scrollY -= totalScrollDistance * (newTimestamp - oldTimestamp) / duration;
            if (scrollY <= 0) return document.scrollingElement.scrollTop = position;
            document.scrollingElement.scrollTop = scrollY;
        }
        oldTimestamp = newTimestamp;
        window.requestAnimationFrame(step);
    }
    window.requestAnimationFrame(step);
}

(function() {

    setTimeout(() => {
        //scrollTo(document.getElementById(window.location.hash.substr(1)).offsetTop + 85, 100);
        document.documentElement.scrollTop = document.getElementById(window.location.hash.substr(1)).offsetTop + 85;
    }, 5000);

})();