// ==UserScript==
// @name         Nico manga download
// @namespace    http://tampermonkey.net/
// @version      1.0
// @description  Just do it
// @author       Tinyblack / Youwang Translation Group
// @match        https://seiga.nicovideo.jp/watch/*
// @grant        none
// ==/UserScript==
(function() {
//创建按钮对象
var downloadicon = document.createElement("button");
downloadicon.style.cssText = 'position:fixed; right:1% ; top:20%; width: 180px; height: 60px;font-size: 16px;cursor: pointer;font-weight: 400;border: 0 solid;background-color: white;outline: 1px solid;transition: box-shadow 0.5s, outline-offset 0.3s, outline 0.3s, border-color 0.3s;';
downloadicon.innerHTML = "下载所有图片";
//控制下载方法
downloadicon.onclick = function downloadimg(){
let file = 1;
let tcanvaslist = document.getElementsByTagName("canvas");
let canvaslist = [];
let indexlist = [];
let min = 0;
for (let i = 0 ; i < tcanvaslist.length ;)  //按元素位于页面上下气泡排序
{
for(let j = 0 ; j < tcanvaslist.length ; j++)
{
if(tcanvaslist[j].getBoundingClientRect().y < tcanvaslist[min].getBoundingClientRect().y)
{
if(indexlist.includes(j) != true)
{
min = j;
}
}
}
canvaslist.push(tcanvaslist[min]);
indexlist.push(min);
i++;
min = i;
}
console.log("canvaslist:"+canvaslist);
console.log("indexlist:"+indexlist);
for (let i = 0 ; i < canvaslist.length ; i++){      //下载
if(canvaslist[i].className != "balloon canvas")
{
let link = document.createElement("a");
link.href = canvaslist[i].toDataURL();
let filetype = ".jpg";
if(canvaslist[i].toDataURL().match("data:image/png;") != null)
{
filetype = ".png";
}
if(canvaslist[i].toDataURL().match("data:image/jpg;") || canvaslist[i].toDataURL().match("data:image/jpeg;") != null)
{
filetype = ".jpg";
}
link.download = file + filetype;
link.click();
file ++;
}
}
};
document.body.appendChild(downloadicon);        //添加下载按钮至网页
})();