// ==UserScript==
// @name         Replace Amazon Button with Morawa Button on Goodreads
// @namespace    http://tampermonkey.net/
// @version      0.3
// @author       Kumi
// @description  Replace the "Buy on Amazon" button with a "Buy at Morawa" button on Goodreads book pages.
// @match        https://www.goodreads.com/book/show/*
// @grant        none
// ==/UserScript==

(function () {
    'use strict';

    // Function to get the ISBN from the Goodreads page
    function getISBN() {
        const scriptTags = document.querySelectorAll('script[type="application/ld+json"]');
        for (let scriptTag of scriptTags) {
            try {
                const jsonData = JSON.parse(scriptTag.textContent);
                if (jsonData['@type'] === 'Book' && jsonData.isbn) {
                    return jsonData.isbn;
                }
            } catch (e) {
                console.error('Error parsing JSON from script tag:', e);
            }
        }
        return null;
    }

    // Function to create the Morawa button
    function createMorawaButton(isbn) {
        const morawaButton = document.createElement('a');
        morawaButton.textContent = 'Buy at Morawa';
        morawaButton.href = `https://www.morawa.at/detail/ISBN-${isbn}`;
        morawaButton.className = 'Button Button--buy Button--medium Button--block';
        morawaButton.setAttribute('role', 'link');
        morawaButton.setAttribute('aria-label', 'Buy at Morawa, link, opens in new tab');
        morawaButton.style.textDecoration = 'none';
        morawaButton.style.color = '#fff';
        morawaButton.style.backgroundColor = '#ff9900';
        morawaButton.style.padding = '10px';
        morawaButton.style.borderRadius = '5px';
        return morawaButton;
    }

    // Main function to replace the Amazon button
    function replaceAmazonButton() {
        const isbn = getISBN();
        if (!isbn) {
            console.log('ISBN not found.');
            return;
        }

        const amazonButtonContainer = Array.from(document.querySelectorAll('.Button__container')).find(container => {
            const button = container.querySelector('button');
            return button && button.textContent.includes('Buy on Amazon');
        });

        if (amazonButtonContainer) {
            const morawaButton = createMorawaButton(isbn);
            amazonButtonContainer.parentNode.replaceChild(morawaButton, amazonButtonContainer);
        } else {
            console.log('Amazon button not found.');
        }
    }

    // Wait for the DOM to load before running the script
    window.addEventListener('load', replaceAmazonButton);
})();