// ==UserScript==
// @name         Zhihu Easy Collapse
// @description  快捷地收起知乎首页的长答案
// @author       wenLiangcan
// @version      0.3
// @namespace    https://github.com/wenLiangcan
// @homepage     https://github.com/wenLiangcan/Userscripts
// @license      GPL version 3
// @copyright    Copyright © 2015 wenLiangcan
// @updateURL
// @downloadURL
// @match        http://www.zhihu.com/*
// @grant        none
// @run-at       document-end
// ==/UserScript==
(function() {
function getLastItem(arr) {
return arr[arr.length - 1];
}
function toArray(obj) {
return Array.prototype.slice.call(obj);
}
function addFloatingCollapseButtons(feeds) {
feeds.forEach(function(feed) {
var collapseButton = getLastItem(feed.getElementsByClassName('collapse'));
if (collapseButton !== undefined) {
var newButton = collapseButton.cloneNode(true);
newButton.onclick = function() {
feed.scrollIntoView(true);
collapseButton.click();
};
newButton.style.position = 'relative';
newButton.style.marginTop = '1px';
newButton.style.marginLeft = '0px';
try {
var votebar = getLastItem(feed.getElementsByClassName('zm-votebar'));
votebar.appendChild(newButton);
} catch (e) {
console.log(e);
}
}
});
}
function getSelectorsBasedOnUrl() {
var selectors = [];
// explore
if (/^http:\/\/www\.zhihu\.com\/explore(\/(#.*?)?)?$/.test(document.URL)) {
selectors = [
'#js-explore-tab > div:nth-child(4) > div',
'#js-explore-tab > div:nth-child(5) > div'
];
}
// main
else if (/^http:\/\/www\.zhihu\.com(\/(#.*?)?)?$/.test(document.URL)) {
selectors = ['#js-home-feed-list'];
}
return selectors;
}
function observeFeedList(feedList) {
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(mutation) {
addFloatingCollapseButtons(toArray(mutation.addedNodes));
});
});
var observerConfig = {
childList: true
};
observer.observe(feedList, observerConfig);
}
getSelectorsBasedOnUrl().forEach(function(selector) {
var feedList = document.querySelector(selector);
observeFeedList(feedList);
});
addFloatingCollapseButtons(
toArray(document.getElementsByClassName('feed-item')));
})();