DOM

Useful library for dealing with the DOM.

Versión del día 25/6/2020. Echa un vistazo a la versión más reciente.

Este script no debería instalarse directamente. Es una biblioteca que utilizan otros scripts mediante la meta-directiva de inclusión // @require https://update.greasyfork.org/scripts/405802/820354/DOM.js

Tendrás que instalar una extensión para tu navegador como Tampermonkey, Greasemonkey o Violentmonkey si quieres utilizar este script.

Necesitarás instalar una extensión como Tampermonkey o Violentmonkey para instalar este script.

Necesitarás instalar una extensión como Tampermonkey o Violentmonkey para instalar este script.

Necesitarás instalar una extensión como Tampermonkey o Userscripts para instalar este script.

Necesitará instalar una extensión como Tampermonkey para instalar este script.

Necesitarás instalar una extensión para administrar scripts de usuario si quieres instalar este script.

(Ya tengo un administrador de scripts de usuario, déjame instalarlo)

Necesitará instalar una extensión como Stylus para instalar este estilo.

Necesitará instalar una extensión como Stylus para instalar este estilo.

Necesitará instalar una extensión como Stylus para instalar este estilo.

Necesitará instalar una extensión del gestor de estilos de usuario para instalar este estilo.

Necesitará instalar una extensión del gestor de estilos de usuario para instalar este estilo.

Necesitará instalar una extensión del gestor de estilos de usuario para instalar este estilo.

(Ya tengo un administrador de estilos de usuario, déjame instalarlo)

// ==UserScript==
// @name DOM
// @namespace https://rafaelgssa.gitlab.io/monkey-scripts
// @version 4.0.1
// @author rafaelgssa
// @description Useful library for dealing with the DOM.
// @match *://*/*
// @require https://greasyfork.org/scripts/405813-monkey-utils/code/Monkey%20Utils.js
// ==/UserScript==

/* global Utils */

/**
 * @typedef {(element?: Element) => void} ElementCallback
 *
 * @typedef {InsertPosition | 'atouter' | 'atinner'} ExtendedInsertPosition
 *
 * @typedef {ElementArrayConstructor<ElementArrayBase, 8>} ElementArray Any higher than 8 is too deep and does not work.
 *
 * **The definition for ElementArrayConstructor is in DOM.d.ts, as it is too complex for JSDoc:**
 * declare type ElementArrayConstructor<T extends [any, any] | string, N extends number> = T extends [
 *   infer A,
 *   infer B
 * ]
 *   ? {
 *       done: [A, B, string | null];
 *       recurse: [
 *         A,
 *         B,
 *         ElementArrayConstructor<ElementArrayBase, ElementArrayDepth[N]>[] | string | null
 *       ];
 *     }[N extends 0 ? 'done' : 'recurse']
 *   : T extends string
 *   ? T
 *   : never;
 *
 * @typedef {[never, 0, 1, 2, 3, 4, 5, 6, 7]} ElementArrayDepth
 *
 * @typedef {{ [K in ElementTag]: [K, ElementAttributes<K> | null] }[ElementTag] | string} ElementArrayBase
 *
 * @typedef {keyof HTMLElementTagNameMap} ElementTag
 *
 * @typedef {ElementArray[] | string} ElementArrayChildren
 *
 * @typedef {Object} MutationTypes
 * @property {boolean} [attributes]
 * @property {boolean} [childList]
 * @property {boolean} [subtree]
 *
 * @typedef {(node: Node) => void} NodeCallback
 */

/**
 * @template {ElementTag} T
 * @typedef {{ [K in keyof ExtendedElement<T>]?: Partial<ExtendedElement<T>[K]> | null }} ElementAttributes
 */

/**
 * @template {ElementTag} T
 * @typedef {HTMLElementTagNameMap[T] & { ref: NodeCallback }} ExtendedElement
 */

// eslint-disable-next-line
const DOM = (() => {
	const _parser = new DOMParser();

	/**
	 * Waits for an element.
	 * @param {string} selectors The selectors to query for the element.
	 * @param {number} timeout How long to wait for the element in seconds. Defaults to 60 (1 minute).
	 * @returns {Promise<Element | undefined>} The element, if found.
	 */
	const dynamicQuerySelector = (selectors, timeout = 60) => {
		return new Promise((resolve) => _checkElementExists(selectors, resolve, timeout));
	};

	/**
	 * @param {string} selectors
	 * @param {ElementCallback} callback
	 * @param {number} timeout
	 */
	const _checkElementExists = (selectors, callback, timeout = 60) => {
		const element = document.querySelector(selectors);
		if (element) {
			callback(element);
		} else if (timeout > 0) {
			window.setTimeout(_checkElementExists, 1000, selectors, callback, timeout - 1);
		} else {
			callback();
		}
	};

	/**
	 * Inserts elements in reference to another element based on element arrays.
	 * @param {Element} reference The element to use as reference.
	 * @param {ExtendedInsertPosition} position Where to insert the elements.
	 * @param {ElementArray[]} arrays The arrays to use.
	 * @returns {HTMLElement[] | []} The inserted elements from the root level, if successful.
	 *
	 * @example
	 * // 'pElement' will contain the P element.
	 * // 'elements' will be an array containing the DIV and the SPAN elements, in this order, if successful.
	 * let pElement;
	 * const elements = DOM.insertElement(document.body, 'beforeend', [
	 *   ['div', { className: 'hello', onclick: () => {} }, [
	 *     'Hello, ', // This is added as a text node.
	 *     ['p', { ref: (ref) => pElement = ref }, 'John'],
	 *     '!' // This is added as a text node.
	 *   ]],
	 *   ['span', null, 'How are you?']
	 * ]);
	 *
	 * @example
	 * // Using array destructuring.
	 * // 'divElement' will contain the DIV element and 'spanElement' will contain the SPAN element, if successful.
	 * let pElement;
	 * const [divElement, spanElement] = DOM.insertElement(document.body, 'beforeend', [
	 *   ['div', { className: 'hello', onclick: () => {} }, [
	 *     'Hello, ', // This is added as a text node.
	 *     ['p', { ref: (ref) => pElement = ref }, 'John'],
	 *     '!' // This is added as a text node.
	 *   ]],
	 *   ['span', null, 'How are you?']
	 * ]);
	 */
	const insertElements = (reference, position, arrays) => {
		const fragment = _buildFragment(arrays);
		if (!fragment) {
			return [];
		}
		const elements = /** @type {HTMLElement[]} */ (Array.from(fragment.children));
		const referenceParent = reference.parentElement;
		switch (position) {
			case 'beforebegin':
				if (referenceParent) {
					referenceParent.insertBefore(fragment, reference);
				}
				break;
			case 'afterbegin':
				reference.insertBefore(fragment, reference.firstElementChild);
				break;
			case 'beforeend':
				reference.appendChild(fragment);
				break;
			case 'afterend':
				if (referenceParent) {
					referenceParent.insertBefore(fragment, reference.nextElementSibling);
				}
				break;
			case 'atouter':
				if (referenceParent) {
					referenceParent.insertBefore(fragment, reference.nextElementSibling);
					reference.remove();
				}
				break;
			case 'atinner':
				reference.innerHTML = '';
				reference.appendChild(fragment);
				break;
			// no default
		}
		if (fragment.children.length > 0) {
			return [];
		}
		return elements;
	};

	/**
	 * Builds a fragment from element arrays.
	 * @param {ElementArray[]} arrays
	 * @returns {DocumentFragment | null} The built fragment, if successful.
	 */
	const _buildFragment = (arrays) => {
		if (!Array.isArray(arrays)) {
			return null;
		}
		// @ts-ignore
		const filteredArrays = arrays.filter(Utils.isSet);
		const fragment = document.createDocumentFragment();
		for (const array of filteredArrays) {
			const element = _buildElement(array);
			fragment.appendChild(element);
		}
		return fragment;
	};

	/**
	 * Builds an element from an element array.
	 * @param {ElementArray} array
	 * @returns {HTMLElement} The built element.
	 */
	const _buildElement = (array) => {
		if (typeof array === 'string') {
			const textNode = document.createTextNode(array);
			return /** @type {HTMLElement} */ (/** @type {unknown} */ (textNode));
		}
		const [tag, attributes, children] = array;
		const element = document.createElement(tag);
		if (attributes) {
			_setElementAttributes(element, attributes);
		}
		if (children) {
			_appendElementChildren(element, children);
		}
		return element;
	};

	/**
	 * Sets attributes for an element.
	 * @template {ElementTag} T
	 * @param {HTMLElement} element
	 * @param {ElementAttributes<T>} attributes
	 */
	const _setElementAttributes = (element, attributes) => {
		const filteredAttributes = Object.entries(attributes).filter(([, value]) => Utils.isSet(value));
		for (const [key, value] of filteredAttributes) {
			if (key === 'ref' && typeof value === 'function') {
				value(element);
			} else if (key.startsWith('on') && typeof value === 'function') {
				const eventType = key.slice(2);
				element.addEventListener(eventType, value);
			} else if (typeof value === 'object') {
				_setElementProperties(element, key, value);
			} else {
				// @ts-ignore
				element[key] = value;
			}
		}
	};

	/**
	 * Sets properties for the attribute of an element.
	 * @param {HTMLElement} element
	 * @param {string} attribute
	 * @param {Object} properties
	 */
	const _setElementProperties = (element, attribute, properties) => {
		const filteredProperties = Object.entries(properties).filter(([, value]) => Utils.isSet(value));
		for (const [key, value] of filteredProperties) {
			// @ts-ignore
			element[attribute][key] = value;
		}
	};

	/**
	 * Appends children to an element from an element array.
	 * @param {HTMLElement} element
	 * @param {ElementArrayChildren} children
	 */
	const _appendElementChildren = (element, children) => {
		if (Array.isArray(children)) {
			const fragment = _buildFragment(children);
			if (fragment) {
				element.appendChild(fragment);
			}
		} else if (typeof children === 'string') {
			const textNode = document.createTextNode(children);
			element.appendChild(textNode);
		}
	};

	/**
	 * Observes a node for mutations.
	 * @param {Node} node The node to observe.
	 * @param {MutationTypes | null} types The types of mutations to observe. Defaults to child list of the node and all its descendants.
	 * @param {NodeCallback} callback The callback to call with each updated / added node.
	 * @returns {MutationObserver} The observer.
	 */
	const observeNode = (node, types, callback) => {
		const observer = new MutationObserver((mutations) =>
			_processNodeMutations(mutations, callback)
		);
		observer.observe(
			node,
			types || {
				childList: true,
				subtree: true,
			}
		);
		return observer;
	};

	/**
	 * @param {MutationRecord[]} mutations
	 * @param {NodeCallback} callback
	 */
	const _processNodeMutations = (mutations, callback) => {
		for (const mutation of mutations) {
			if (mutation.type === 'attributes') {
				callback(mutation.target);
			} else {
				mutation.addedNodes.forEach(callback);
			}
		}
	};

	/**
	 * Parses an HTML string into a DOM.
	 * @param {string} html The HTML string to parse.
	 * @returns {Document} The parsed DOM.
	 */
	const parse = (html) => {
		return _parser.parseFromString(html, 'text/html');
	};

	return {
		dynamicQuerySelector,
		insertElements,
		observeNode,
		parse,
	};
})();