// ==UserScript==
// @name         微博相册原图批量下载
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  提供微博微相册 ( photo.weibo.com ) 的专辑内单页原图批量下载
// @author       ShuangruiYang
// @match        *://photo.weibo.com/*/talbum/index*
// @grant        none
// @license MIT
// @downloadURL none
// ==/UserScript==

(function () {
	'use strict';


	function batch_download() {
		let image_list = document.querySelectorAll("ul.photoList li a img");
		let number = image_list.length;
		// 验证预览图是否未加载 是则 等待1秒后再次验证
		if (number == 0) {
			setTimeout(batch_download, 1000);
			return;
		}

		for (let i = 0; i < number; i++) {
			let id_match = image_list[i].parentNode.href.match(/\d+/g);
			let album_id = id_match[2];
			let photo_id = id_match[1];

			// 格式化 原图下载链接
			let download_$a = document.createElement('a');
			download_$a.id = "download_" + i;
			download_$a.href = image_list[i].src.replace(/(.+)\/(\w+)\/(\w+)/, "$1/large/$3");
			download_$a.download = album_id + "_" + photo_id;

			fetch(download_$a.href)
				.then(res => res.blob())
				.then(blob => {
					var blob_url = window.URL.createObjectURL(blob);
					download_$a.href = blob_url;
					download_$a.click();
					window.URL.revokeObjectURL(blob_url);
				});
		}
	}

	function init() {
		let batch_download_$button = document.createElement("button");
		batch_download_$button.id = "batch_download";
		batch_download_$button.textContent = "批量下载原图";
		batch_download_$button.style.fontWeight = "bolder";
		batch_download_$button.onclick = batch_download;
		document.querySelector(".m_share_like").appendChild(batch_download_$button);
	}

	init();
})();