// ==UserScript==
// @name         Hackernews Scroll to Next/Previous Top-Level Comment
// @namespace    https://news.ycombinator.com/
// @version      0.2
// @description  Adds a button and keyboard shortcuts (down and up arrows) that scroll to quickly and smoothly navigate to the next/previous top-level comment. This scroller saves time by allowing you to skip comment threads you're not interested in. An alternative to collapsing the thread.
// @author       Jonathan Woolf
// @match        https://news.ycombinator.com/*
// @grant        none
// ==/UserScript==
(function() {
'use strict';
const button = document.createElement('button');
button.textContent = '⬇️';
button.style.cssText = `
position: fixed;
bottom: 10px;
left: 10px;
z-index: 999;
background-color: rgb(255, 198, 156);
color: #fff;
border: 6px solid rgb(255, 102, 0);
background-color: rgb(255, 198, 156);
border-radius: 50%;
width: 40px;
height: 40px;
font-size: 24px;
text-align: center;
line-height: 40px;
cursor: pointer;
display: flex;
justify-content: center;
align-items: center;
font-size: 91%;
`;
document.body.appendChild(button);
const comments = [...document.querySelectorAll('td.ind[indent="0"]')];
let currentCommentIndex = 0;
button.addEventListener('click', scrollToNextComment);
document.addEventListener("keydown", handleKeyPress);
function handleKeyPress(event) {
if (event.code === "ArrowDown") {
event.preventDefault();
scrollToNextComment();
} else if (event.code === "ArrowUp") {
event.preventDefault();
scrollToPreviousComment();
}
}
function scrollToNextComment() {
if (currentCommentIndex === comments.length - 1) {
currentCommentIndex = 0;
} else {
currentCommentIndex++;
}
comments[currentCommentIndex].closest('tr').scrollIntoView({ behavior: 'smooth', block: 'start' });
}
function scrollToPreviousComment() {
if (currentCommentIndex === 0) {
currentCommentIndex = comments.length - 1;
} else {
currentCommentIndex--;
}
comments[currentCommentIndex].closest('tr').scrollIntoView({ behavior: 'smooth', block: 'start' });
}
})();