INFO283-ebook-navigation.js

// ==UserScript==
// @name         AI: Foundations of Computational Agents key navigation
// @namespace    https://torrottum.no
// @version      0.1
// @description  Allows you to use arrow keys or vi-style (hkl) keys to navigate the Artificial Intelligence: Foundations of Computational Agents book
// @author       Tor Røttum
// @match        http://artint.info/2e/*
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    window.onkeydown = function(event) {
        var prev = document.querySelector('.prev');
        var up = document.querySelector('.up');
        var next = document.querySelector('.next');

        var key = event.key;

        if ((key === 'ArrowLeft' || key === 'h') && prev) {
            left.parentNode.click();
        }

        if ((key === 'ArrowUp' || key === 'k') && up) {
            up.parentNode.click();
        }

        if ((key === 'ArrowRight' || key === 'l') && next) {
            next.parentNode.click();
        }
    };
})();