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// ==UserScript==
// @name         Pixiv Number of Illusts Icon
// @description  Add icon indicates number of illusts into pixiv illust page
// @namespace    https://gist.github.com/tkrkt
// @version      0.1
// @match        https://www.pixiv.net/member_illust.php*
// @grant        none
// ==/UserScript==

(function() {
    'use strict';
    const isLoaded = () => !!document.querySelector('.work-info .meta') && !!document.querySelector('.works_display');
    const waitForLoad = callback => {
        if (isLoaded()) {
            callback();
        } else {
            setTimeout(() => waitForLoad(callback), 1000);
        }
    };

    waitForLoad(() => {
        const multiple = Array.from(document.querySelectorAll('.work-info .meta li')).filter(li => li.textContent.indexOf('複数枚投稿') >= 0);
        if (multiple.length) {
            const page = multiple[0].textContent.match(/\d+/)[0];

            const style = document.createElement('style');
            style.textContent = `
.multiple ._icon-20._icon-files:after {
    content: "${page}";
    color: gray;
    font-size: 10px;
    position: absolute;
    top: 8px;
    left: 8px;
    width: 14px;
    height: 14px;
    line-height: 14px;
    text-align: center;
    white-space: pre;
}`;
            document.head.appendChild(style);
            document.querySelector('.multiple ._icon-20._icon-files').style.position = 'relative';
        }
    });
})();