Sam And Fuzzy Arrow Keys And Randomizer Userscript

samAndFuzzyArrowKeysAndRandomizer.user.js

// ==UserScript==
// @name        Sam & Fuzzy Arrow Keys and Randomizer
// @namespace   https://gist.github.com/JulianWebb
// @version     0.2
// @author      JulianWebb
// @description Adds the ability to navigate the comic using just the left and right arrow keys
// @icon        https://www.samandfuzzy.com/favicon.ico
// @match       https://www.samandfuzzy.com/*
// @match       http://www.samandfuzzy.com/*
// @grant       none
// ==/UserScript==

(function() {
  'use strict';
  
  // Randomizer Init
  // Does this provide an accurate count? Not really.
  // Does this provide a close enough count for our purposes? Yeah
  
  var start_date = new Date("May 27, 2002"); //Date of first Sam & Fuzzy
  var today_date = new Date();
  
  var week_in_milliseconds = 604800000;
  var weeks = 0;
  
  for (var date = start_date.getTime(); date <= today_date.getTime(); date += week_in_milliseconds) {
    weeks++
  }
  
  var rand_padding = 10;
  var rand_min = rand_padding;
  var rand_max = (weeks * 3) - rand_padding;
  
  // Only add listeners if there is a comic on the page
  if (document.querySelector("img.comic-image")) {
    //Key Listeners
    document.addEventListener("keydown", event => {
      switch (event.key) {
        case "ArrowLeft":
          let prevPage = document.querySelector("li.prev-page > a");
          prevPage.click()
          break;
        case "ArrowRight": 
          let nextPage = document.querySelector("li.next-page > a");
          nextPage.click();
          break;
        case "r":
          let rand_page = Math.floor(Math.random() * (rand_max - rand_min)) + rand_min;
          window.location = "https://www.samandfuzzy.com/" + rand_page;
          break;
        default: return;
      }
    });
    
    console.log('Sam & Fuzzy Arrow Keys and Randomizer is working!');
  } else {
  	console.log('No comic on page; I sleep.');  
  }
   
  
})();