Observe

Observe and wait for elements

Tätä skriptiä ei tulisi asentaa suoraan. Se on kirjasto muita skriptejä varten sisällytettäväksi metadirektiivillä // @require https://update.greasyfork.org/scripts/552301/1676523/Observe.js.

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(I already have a user script manager, let me install it!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name         Observe
// @license      MIT
// @version      2.2
// @description  Observe and wait for elements
// @author       tukars
// @match        *://*/*
// ==/UserScript==

(function () {
	const timeStamp = function () {
		const now = new Date();
		const pad = (num, size) => String(num).padStart(size, "0");

		const hours = pad(now.getHours(), 2);
		const minutes = pad(now.getMinutes(), 2);
		const seconds = pad(now.getSeconds(), 2);
		const milliseconds = pad(now.getMilliseconds(), 3);

		return `${hours}:${minutes}:${seconds}.${milliseconds}`;
	};

	const contextPrint = function (message, ENABLE_DEBUG_LOGGING) {
		const messageTime = () => `[${message}] ${timeStamp()} -`;

		const log = function (...args) {
			console.log(messageTime(), ...args);
		};
		const warn = function (...args) {
			console.warn(messageTime(), ...args);
		};
		const error = function (...args) {
			console.error(messageTime(), ...args);
		};
		const info = function (...args) {
			console.info(messageTime(), ...args);
		};
		var debug = function (...args) {
			console.debug(messageTime(), ...args);
		};
		if (!ENABLE_DEBUG_LOGGING) {
			debug = function () { };
		}

		return { log, warn, error, info, debug };
	};

	const observeChildren = function (element, config, callback) {
		const observer = new MutationObserver((mutationsList) => {
			for (const mutation of mutationsList) {
				if (mutation.type === "childList") {
					callback(Array.from(mutation.addedNodes));
				}
			}
		});
		const use_config = config || { childList: true, subtree: false };
		observer.observe(element, use_config);
		return observer;
	};

	const observeChildrenWithFilter = function (element, config, filter, callback) {
		return observeChildren(element, config, (addedNodes) =>
			callback(addedNodes.filter(filter))
		);
	};
	
	const observeChildrenWithSelector = function(element, config, selector, callback) {
		return observeChildrenWithFilter(
			element,
			config,
			(node) =>
				node.nodeType === Node.ELEMENT_NODE &&
				node.matches(selector),
			callback
		);
	};
	
	const observeAndHandle = function(
		element, selector, fun, config = { childList: true, subtree: true } 
	) { 
		return observeChildrenWithSelector(element, config, selector, (nodes) => 
			nodes.forEach((node) => fun(node))
		);
	};

	async function waitForElement(selector, timeoutMs = 0, parent = document) {
		return new Promise((resolve, reject) => {
			const element = parent.querySelector(selector);
			if (element) {
				resolve(element);
				return;
			}
			const observer = observeChildren(parent, { childList: true, subtree: true }, () => {
				const el = parent.querySelector(selector);
				if (!el) { return; }
				
				observer.disconnect();
				resolve(el);
			});
			
			if (timeoutMs == 0) { return; }
			
			setTimeout(() => {
				observer.disconnect();
				reject(new Error(`waitForElement timed out after ${timeoutMs}ms for selector: "${selector}"`));
			}, timeoutMs);
		});
	}
	
	const NAMESPACE = { author: "tukars", library: "Observe" };
	const assign = function (namespace, object) {
		const root = "userscript";
		const domain = "com";
		const author = namespace.author;
		const library = namespace.library;
		window[root] = window[root] || {};
		window[root][domain] = window[root][domain] || {};
		window[root][domain][author] = window[root][domain][author] || {};
		if (window[root][domain][author][library]) { return; }
		window[root][domain][author][library] = object;
	}

	assign(NAMESPACE, {
		timeStamp,
		contextPrint,
		observeChildren,
		observeChildrenWithFilter,
		observeChildrenWithSelector,
		observeAndHandle,
		waitForElement
	});
})();