// ==UserScript==
// @name        Upsize Stand-Alone Images
// @author      Jefferson "jscher2000" Scher
// @namespace   JeffersonScher
// @version     0.5.2
// @copyright   Copyright 2017 Jefferson Scher
// @license     BSD-3-Clause
// @description Proportionally enlarge smaller stand-alone images
// @match       http*://*/*
// @grant       none
// ==/UserScript==
var tgt;
function resizeImg(e){
var whratio = tgt.width / tgt.height;
var wnew = window.innerWidth;
var hnew = Math.round(wnew * (1 / whratio));
if (hnew > window.innerHeight){
hnew = window.innerHeight;
wnew = Math.round(hnew * whratio);
}
tgt.width = wnew;
tgt.height = hnew;
}
var resizeTimeout;
function resizeThrottler(){
if(!resizeTimeout){
resizeTimeout = window.setTimeout(function(){resizeTimeout = null; resizeImg();}, 200);
}
}
if (document.querySelector('head').innerHTML.indexOf('TopLevelImageDocument.css') > -1) {
tgt = document.querySelector('body img'); // first image in body
if (tgt.className.indexOf('shrinkToFit') == -1) {
window.addEventListener('resize', resizeThrottler, false);
window.setTimeout(resizeImg, 100);
} else {
// if Firefox is already managing resizing, do nothing
}
}