// ==UserScript==
// @name         MB: CoverArt Uploads Auto Retry on Error
// @namespace    https://greasyfork.org/users/321857-anakunda
// @version      1.00
// @match        https://musicbrainz.org/release/*/add-cover-art
// @match        https://musicbrainz.org/release/*/add-cover-art?*
// @description  Try to take over the world!
// @run-at       document-end
// @author       Anakunda
// @copyright    2023, Anakunda (https://greasyfork.org/users/321857-anakunda)
// @license      GPL-3.0-or-later
// @grant        GM_notification
// @grant        GM_getValue
// @downloadURL none
// ==/UserScript==

{

'use strict';

const button = document.body.querySelector('button#add-cover-art-submit');
if (button == null) throw 'Submit button not found';
let hadErrors = false, active = true, retryDelay = GM_getValue('retry_delay', 5);
const retry = elem => { if (active && elem instanceof HTMLElement && !elem.disabled) elem.click() };
new MutationObserver(function(ml, mo) {
	for (let mutation of ml) if (!mutation.target.disabled)
		if (Array.prototype.some.call(document.querySelectorAll('form#add-cover-art > table > tbody > tr > td > span.msg.error'),
				span => span.style.display != 'none' && /^⚠ (?:Server busy|Error)\b/.test(span.textContent.trim()))) {
			hadErrors = true;
			if (active) setTimeout(retry, retryDelay * 1000 || 0, mutation.target);
			let btnCancel = document.body.querySelector('button#autoretry');
			if (btnCancel == null) {
				const captions = ['Suspend AutoRetry', 'Resume AutoRetry'];
				btnCancel = Object.assign(document.createElement('button'), {
					textContent: captions[0],
					id: 'autoretry',
					style: 'padding: 5px 10px 5px 7px;',
					onclick: function(evt) {
						evt.currentTarget.textContent = captions[(active = !active) ? 0 : 1];
						return false;
					},
				});
				button.insertAdjacentElement('afterend', btnCancel);
			}
		} else if (hadErrors) {
			//mo.disconnect();
			let btnCancel = document.body.querySelector('button#cancel-autoretry');
			if (btnCancel != null) btnCancel.remove();
			active = true;
			GM_notification({
				text: 'Successfully completed',
				title: 'MusicBrainz',
				highlight: true,
				silent: false,
			});
		}
}).observe(button, { attributes: true, attributeFilter: ['disabled'] });

}