// ==UserScript==
// @name         Remove zhihu video
// @namespace    https://www.Removezhihuvideo.com
// @version      0.2
// @description  Just remove zhihu video
// @author       You
// @match        https://www.zhihu.com/
// @icon         http://zhihu.com/favicon.ico
// @grant        none
// @run-at       document-body
// @downloadURL none
// ==/UserScript==


let inited = false;

function callback(mutationsList) {

	for (let m of mutationsList) {
		if (m.type == 'childList' && m.addedNodes.length > 0) {

			for (let node of m.addedNodes) {
				//console.log('addnodes:', node);
				if (!inited && node.tagName === 'DIV')
				{
					for (let cnode of node.querySelectorAll('.TopstoryItem')) {
						removeIfVideo(cnode);
					}
					inited = true;
				}
				if (node.tagName === 'DIV' && node.classList.contains('TopstoryItem')) {
					removeIfVideo(node);
				}
			}
		}
	}
}

for (let node of document.querySelectorAll('.TopstoryItem')) {
	removeIfVideo(node);
}


const observer = new MutationObserver(callback);
observer.observe(document.body, {
	childList: true,
	subtree: true
})

function removeIfVideo(node) {
	let n = node.querySelector('.ZVideoItem');
	if (n) {
		let m = n.querySelector('iframe');
		if (m && m.src &&
			m.src.indexOf('www.zhihu.com/video/') >= 0 ||
			m.src.indexOf('video.zhihu.com') >= 0
		   ) {
			const m2 = node.querySelector('.ZVideoItem-video');
			if (m2 && n.children.length === 3) {
				n.children[1].style.display = 'none';
				n.children[2].style.display = 'none';
				let div = document.createElement('div');
				div.innerHTML = '<button class="Button">show video</button>'
				n.appendChild(div);
				div.addEventListener('click', function () {
					n.children[1].style.display = '';
					n.children[2].style.display = '';
					div.remove();
				});
			}
		}
	}
}