YouTube Playlist Close

Allow quick closing of playlists
当前为 2016-12-09 提交的版本，查看最新版本。
换行
// ==UserScript==
// @name         YouTube Playlist Close
// @version      1.0
// @description  Allow quick closing of playlists
// @author       AjaxGb
// @match        http*://www.youtube.com/*
// @run-at       document-start
// @resource     button https://raw.githubusercontent.com/AjaxGb/YouTube-Playlist-Close/master/closeMedium.png
// @grant        GM_getResourceURL
// @noframes
// @namespace https://greasyfork.org/users/85711
// ==/UserScript==

(function(){
	'use strict';

	function getQueryArgs(query){
		query = query || window.location.search.substring(1);
		if(!query) return {};
		return query.split('&').reduce(function(prev, curr){
			const p = curr.split('=');
			prev[decodeURIComponent(p[0])] = p[1] ? decodeURIComponent(p[1]) : p[1];
			return prev;
		}, {});
	}

	function setQueryArgs(query){
		if(!query) return;
		let search = '';
		for(let prop in query){
			if(query[prop] === undefined){
				search += '&'+encodeURIComponent(prop);
			}else{
				search += '&'+encodeURIComponent(prop)+'='+encodeURIComponent(query[prop]);
			}
		}
		window.location.search = '?' + search.substr(1);
	}

	const b = document.createElement('button'), s = b.style;
	s.width  = '26px';
	s.height = '28px';
	s.right = s.top = '0';
	s.background = 'url("' + GM_getResourceURL('button') + '") center';
	s.position = 'absolute';
	s.cursor = 'pointer';
	s.opacity = 0.5;
	b.classList.add('yt-uix-tooltip');
	b.title = 'Close playlist';

	b.onmouseenter = function(){
		s.opacity = 0.6;
	};
	b.onmouseleave = function(){
		s.opacity = 0.5;
	};
	b.onclick = function(){
		const q = getQueryArgs();
		q.time_continue = document.getElementById('movie_player').getCurrentTime()|0;
		delete q.list;
		delete q.index;
		setQueryArgs(q);
	};

	function addButton(p){
		p.style.position = 'relative';
		p.appendChild(b);
	}

	const observer = new MutationObserver(function(mrs){
		if(document.contains(b)) return;
		for(let i = mrs.length - 1; i >= 0; --i){
			const t = mrs[i].target;
			if(t){
				if(t.classList && t.classList.contains('playlist-info')){
					addButton(t);
				}else if (t.getElementsByClassName){
					const p = t.getElementsByClassName('playlist-info')[0];
					if(p) addButton(p);
				}
			}
		}
	});
	observer.observe(document.documentElement, {
		childList: true,
		subtree: true
	});
})();