// ==UserScript==
// @name         切换百度谷歌搜索引擎
// @namespace    http://tampermonkey.net/
// @version      0.8
// @description  在百度和谷歌搜索之间快速切换的脚本
// @author       Blazing
// @match        https://www.google.com/*
// @match        https://www.google.com.hk/*
// @match        https://www.google.com.tw/*
// @match        https://www.google.co.jp/*
// @match        https://www.google.co.kr/*
// @match        https://www.baidu.com/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=google.com.hk
// @grant        none
// @license      MIT
// @downloadURL none
// ==/UserScript==

(function () {
    'use strict';

    // 搜索引擎配置
    const SEARCH_ENGINES = {
        google: {
            domainPrefix: 'www.google.',  // 使用前缀匹配
            pathStart: '/search',
            queryParam: 'q',
            searchUrl: 'https://www.google.com/search?q='
        },
        baidu: {
            domain: 'www.baidu.com',
            pathStart: '/s',
            queryParam: 'wd',
            searchUrl: 'https://www.baidu.com/s?wd='
        }
    };

    // 获取当前搜索引擎和目标搜索引擎
    function getCurrentEngine(domain) {
        return Object.entries(SEARCH_ENGINES).find(([_, config]) =>
                                                   config.domains.includes(domain))?.[0];
    }

    function getTargetEngine(currentEngine) {
        return currentEngine === 'google' ? 'baidu' : 'google';
    }

    // 获取搜索词
    function getSearchQuery(engine) {
        const queryParams = new URLSearchParams(window.location.search);
        return queryParams.get(SEARCH_ENGINES[engine].queryParam);
    }

    // 执行搜索
    function openSearch(query, engine) {
        if (!query) return;
        const url = SEARCH_ENGINES[engine].searchUrl + encodeURIComponent(query);
        window.open(url, '_self');
    }

    // 处理快捷键
    function handleHotkey(e) {
        if (!(e.ctrlKey && e.shiftKey && e.key === 'S')) return;

        e.preventDefault();

        const currentDomain = window.location.hostname;
        const currentPath = window.location.pathname;

        const currentEngine = getCurrentEngine(currentDomain);
        if (!currentEngine) return;

        const engineConfig = SEARCH_ENGINES[currentEngine];
        if (!currentPath.startsWith(engineConfig.pathStart)) return;

        const searchQuery = getSearchQuery(currentEngine);
        const targetEngine = getTargetEngine(currentEngine);

        openSearch(searchQuery, targetEngine);
    }

    // 添加搜索引擎切换按钮
    function addSearchEngineButton() {
        const currentDomain = window.location.hostname;
        let searchQuery;

        // 判断是否为谷歌域名
        const isGoogle = currentDomain.startsWith(SEARCH_ENGINES.google.domainPrefix);

        // 针对不同搜索引擎获取搜索词
        if (isGoogle) {
            searchQuery = new URLSearchParams(window.location.search).get('q');
        } else if (currentDomain === SEARCH_ENGINES.baidu.domain) {
            const urlParams = new URLSearchParams(window.location.search);
            searchQuery = urlParams.get('wd');
        }

        if (!searchQuery) return;

        if (isGoogle) {
            // 在谷歌搜索页添加百度搜索按钮
            const allTab = document.querySelector('[aria-current="page"]');
            if (allTab && allTab.parentElement && allTab.parentElement.nextElementSibling) {
                const existingButton = allTab.parentElement.parentElement.querySelector('.nPDzT[data-search-engine="baidu"]');
                if (!existingButton) {
                    const baiduButton = document.createElement('a');
                    baiduButton.className = 'nPDzT T3FoJb';
                    baiduButton.setAttribute('data-search-engine', 'baidu');
                    baiduButton.href = `https://www.baidu.com/s?wd=${encodeURIComponent(searchQuery)}`;
                    baiduButton.innerHTML = '<div class="YmvwI">百度</div>';
                    allTab.parentElement.parentElement.insertBefore(
                        baiduButton,
                        allTab.parentElement.nextElementSibling
                    );
                }
            }
        } else if (currentDomain === SEARCH_ENGINES.baidu.domain) {
            // 在百度搜索页添加谷歌搜索按钮
            const webTab = document.querySelector('.cur-tab');
            if (webTab && webTab.nextElementSibling) {
                const existingButton = webTab.parentElement.querySelector('[data-search-engine="google"]');
                if (!existingButton) {
                    const googleButton = document.createElement('a');
                    googleButton.setAttribute('data-search-engine', 'google');
                    googleButton.href = `https://www.google.com/search?q=${encodeURIComponent(searchQuery)}`;
                    googleButton.innerHTML = '<span>谷歌</span>';
                    googleButton.style.cssText = webTab.nextElementSibling.style.cssText;
                    webTab.parentElement.insertBefore(googleButton, webTab.nextElementSibling);
                }
            }
        }
    }

    // 初始化函数
    function init() {
        document.addEventListener('keydown', handleHotkey);
        addSearchEngineButton();

        const observer = new MutationObserver(() => {
            if (window.location.href !== lastUrl) {
                lastUrl = window.location.href;
                setTimeout(addSearchEngineButton, 100);
            }

            const currentDomain = window.location.hostname;
            const isGoogle = currentDomain.startsWith(SEARCH_ENGINES.google.domainPrefix);

            if (currentDomain === SEARCH_ENGINES.baidu.domain) {
                const webTab = document.querySelector('.cur-tab');
                if (webTab && !webTab.parentElement.querySelector('[data-search-engine="google"]')) {
                    addSearchEngineButton();
                }
            } else if (isGoogle) {
                const allTab = document.querySelector('[aria-current="page"]');
                if (allTab && !allTab.parentElement.parentElement.querySelector('[data-search-engine="baidu"]')) {
                    addSearchEngineButton();
                }
            }
        });

        observer.observe(document.body, {
            childList: true,
            subtree: true
        });
    }

    let lastUrl = window.location.href;
    init();
})();