// ==UserScript==
// @name         豆瓣读书(Douban)跳转到Zlib搜索
// @namespace    http://tampermonkey.net/
// @version      0.1.1
// @description  Adds a hyperlink to the ISBN on Douban book pages to search on Zlib.
// @author       tianyw0
// @match        https://book.douban.com/subject/*
// @grant        none
// @license MIT
// @downloadURL none
// ==/UserScript==

(function() {
    'use strict';

    // 获取 ISBN 号
    function getISBN() {
        const infoDiv = document.querySelector('#info');
        if (infoDiv) {
            const infoText = infoDiv.textContent;
            const isbnRegex = /ISBN:\s*(\d{13}|\d{10})/i;
            const match = infoText.match(isbnRegex);
            if (match) {
                return match[1].trim();
            }
        }
        return null;
    }

    // 将 ISBN 改成超链接
    function convertISBNToLink() {
        const isbn = getISBN();
        const bookname = document.querySelector('span[property="v:itemreviewed"]').textContent;
        if (isbn && bookname) {
            const infoDiv = document.querySelector('#info');
            const spans = infoDiv.querySelectorAll('span.pl');
            for (let span of spans) {
                if (span.textContent.trim() === 'ISBN:') {
                    const nextSpan = span.nextSibling;
                    if (nextSpan) {
                        const link = document.createElement('a');
                        link.href = `https://singlelogin.re/s/${isbn + ' ' + bookname}`;
                        link.target = '_blank';
                        link.textContent = nextSpan.textContent;
                        span.insertAdjacentElement('afterend', link);
                        console.log(nextSpan);
                        nextSpan.remove();
                        break;
                    }
                }
            }
        }
    }

    // 页面加载完成后转换 ISBN 为超链接
    window.addEventListener('load', convertISBNToLink);
})();