// ==UserScript==
// @name A Gelbooru Viewer
// @namespace http://tampermonkey.net/
// @version 1.0.1
// @description Adds a download button and makes thumbnails a little bigger. Make shure to add (.png, .jpeg, .jpg, etc) to the tampermonkey download whitelist
// @author Anonymous
// @match https://gelbooru.com/*page=post*s=list*
// @grant GM_download
// @grant GM_xmlhttpRequest
// ==/UserScript==
(function() {
'use strict';
// Your code here...
function setCustomStyles(){
const customStyles = document.createElement("style");
customStyles.innerHTML = "" +
".thumbnail-preview {" +
"max-width: unset;"+
"width: 30%;" +
"min-height: 200px;" +
"max-height: unset;" +
"height: 500px;"+
"}" +
".thumbnail-preview span {display: contents;}"+
".thumbnail-preview a {display: contents;}"+
".thumbnail-preview button {width: 100%; height: 25px; background-color: blue; color: white; text-decoration:none;border:none;}"+
".thumbnail-preview button[disabled] {background-color: gray; color: black;}"+
".thumbnail-preview button[data-done] {background-color: green;}"+
".thumbnail-preview button.secondary {background-color: gray;}"+
".thumbnail-preview img {"+
"object-fit: contain;" +
"width: 100%;" +
"height: calc(100% - 50px);" +
"} "+
".next-page-message-container {display:flex;align-items:center;width:100%;height:100px;margin:0;background-color:darkgray;} "+
".next-page-message-container p {width:fit-content;margin:auto;font-size:3em;}";
document.head.appendChild(customStyles);
}
function parsePaginationInfo(doc){
let currentPage,
nextPage, nextPageUrl,
previousPage,previousPageUrl;
const currentPageEl = doc.querySelector(".pagination b");
if (currentPageEl){
currentPage = currentPageEl.innerText;
} else {
console.debug("cant parse current page");
}
const aList = Array.from(doc.querySelectorAll(".pagination a"));
for (let i=0; i < aList.length; i++){
const a = aList[i];
const altText = a.getAttribute("alt");
if (!altText) { continue }
switch(altText){
case "next": {
nextPage = altText;
nextPageUrl = a.href;
break;
}
case "back": {
previousPage = altText;
previousPageUrl = a.href;
break;
}
}
}
const alertIfNotFound = (name, value) => {
if (!value) { console.debug( name + " was not found"); }
}
alertIfNotFound("nextPage", nextPage);
alertIfNotFound("previousPage", previousPage);
return {currentPage,
nextPage, nextPageUrl,
previousPage,previousPageUrl}
}
function parseThumbPreview(el){
const a = el.querySelector("a");
const img = el.querySelector("img");
if (!a || !img){
throw new Error("parse error " + el.outerHTML);
}
const thumbUrl = img.src;
const pageUrl = a.href;
if (!thumbUrl || !pageUrl) {
throw new Error("parse error " + el.outerHTML);
}
return {thumbUrl, pageUrl}
}
function parseDetailPage(doc){
let originalImageUrl = undefined;
doc.querySelectorAll("#tag-list a").forEach(a=>{
if (a.innerText === "Original image"){
originalImageUrl = a.href;
}
});
if (!originalImageUrl) {
throw new Error("parse error");
}
return {originalImageUrl}
}
async function getDetailPageDoc(url){
const response = await fetch(url, {method:"GET"});
if (!response.ok){ throw new Error("request error", response) }
const text = await response.text();
return new DOMParser().parseFromString(text,"text/html");
}
async function downloadImage(url, saveAs=false){
const name = url.substring(url.lastIndexOf("/")+1);
return new Promise((resolve, reject)=>{
GM_download({
url,
name,
saveAs,
onload: (data)=>{
console.debug("GM_download.onload", data);
resolve();
},
onerror: (e)=>{
console.debug("GM_download.onerror", e);
reject(e);
}
});
});
}
async function downloadOriginalFromDetailPage(url){
const doc = await getDetailPageDoc(url);
console.debug("page fetched");
const data = parseDetailPage(doc);
console.debug("page parsed", data);
await downloadImage(data.originalImageUrl);
console.debug("image downloaded");
return;
}
// https://stackoverflow.com/questions/1038727/how-to-get-browser-width-using-javascript-code
function getWidth() {
return Math.max(
document.body.scrollWidth,
document.documentElement.scrollWidth,
document.body.offsetWidth,
document.documentElement.offsetWidth,
document.documentElement.clientWidth
);
}
function getHeight() {
return Math.max(
document.body.scrollHeight,
document.documentElement.scrollHeight,
document.body.offsetHeight,
document.documentElement.offsetHeight,
document.documentElement.clientHeight
);
}
function openChildWindow(url,name="page",w=null,h=null) {
// http://www.nigraphic.com/blog/java-script/how-open-new-window-popup-center-screen
if (!w) { w = getWidth() * 0.8; }
if (!h) { h = getHeight() * 0.8; }
const dualScreenLeft = window.screenLeft != undefined ? window.screenLeft : screen.left;
const dualScreenTop = window.screenTop != undefined ? window.screenTop : screen.top;
const width = window.innerWidth ? window.innerWidth : document.documentElement.clientWidth ? document.documentElement.clientWidth : screen.width;
const height = window.innerHeight ? window.innerHeight : document.documentElement.clientHeight ? document.documentElement.clientHeight : screen.height;
const left = ((width / 2) - (w / 2)) + dualScreenLeft;
const top = ((height / 2) - (h / 2)) + dualScreenTop;
const windowref = window.open(url, name, `width=${w},height=${h},top=${top},left=${left},resizable,location=no,toolbar=no,menubar=no,status=no,titlebar=0`);
}
function setOnScrollBottomHandler(handler){
window.onscroll = function(e) {
let pageHeight=document.documentElement.offsetHeight,
windowHeight=window.innerHeight,
scrollPosition=window.scrollY || window.pageYOffset || document.body.scrollTop + (document.documentElement && document.documentElement.scrollTop || 0);
if (pageHeight*0.98 <= (windowHeight+scrollPosition)) {
console.debug('bottom reached');
handler(e);
}
};
}
function addButtons(){
document.querySelectorAll(".thumbnail-preview").forEach(el=>{
const item = parseThumbPreview(el);
const button = document.createElement("button");
button.innerText = "download";
button.addEventListener("click", async e=> {
try{
button.setAttribute("disabled","disabled");
button.innerText = "downloading..."
await downloadOriginalFromDetailPage(item.pageUrl);
button.removeAttribute("disabled");
button.dataset.done=true;
button.innerText = "done";
}
catch(e) {
button.innerText = "error";
console.error(e);
}
});
const openPageButton = document.createElement("button");
openPageButton.classList.add("secondary");
openPageButton.innerText = "open details";
openPageButton.onclick = (e) => {
e.preventDefault();
openChildWindow(item.pageUrl, "Detail");
}
el.appendChild(button);
el.appendChild(openPageButton);
});
}
function addLoadOnScrollBottom(){
const pagination = parsePaginationInfo(document);
if (pagination.nextPage) {
const nextPageMessageContainer = document.createElement("footer");
const nextPageMessageEl = document.createElement("p");
nextPageMessageEl.innerText = "loading next page";
nextPageMessageContainer.classList.add("next-page-message-container");
nextPageMessageContainer.appendChild(nextPageMessageEl);
document.body.appendChild(nextPageMessageContainer);
// Hide lasts br to show next page message sooner
const containerPushBr = Array.from(document.querySelectorAll(".contain-push br"));
let count = 0, limit=6;
for (let i=containerPushBr.length - 1;i >= 0 && count < limit ;i--){
containerPushBr[i].style.display = "none";
count++;
}
setOnScrollBottomHandler(e=>{window.location.replace(pagination.nextPageUrl)})
}
}
function init(){
setCustomStyles();
addButtons();
addLoadOnScrollBottom();
}
init();
})();
