// ==UserScript==
// @name               Opens “Tools” Menu by Default on Google
// @name:zh-TW         預設開啟 Google 的「工具」選單
// @name:zh-CN         预设开启 Google 的“工具”选单
// @description        Opens the “Tools” menu on Google Search automatically when page loaded.
// @description:zh-TW  在 Google 搜尋載入後自動打開「工具」選單。
// @description:zh-CN  在 Google 搜索载入后自动打开“工具”选单。
// @icon               https://wsrv.nl/?url=https://www.google.com/images/branding/googleg/1x/googleg_standard_color_128dp.png
// @author             Jason Kwok
// @namespace          https://jasonhk.dev/
// @version            1.1.4
// @license            MIT
// @match              https://www.google.com/search
// @match              https://www.google.com/search?*
// @run-at             document-end
// @grant              none
// @supportURL         https://greasyfork.org/scripts/460247/feedback
// @downloadURL none
// ==/UserScript==

const TOOLS_BUTTON_ATTRIBUTES = [
    ["aria-controls", "hdtbMenus"],
    ["jsname", "I4bIT"],
    ["jscontroller", "LbcJwc"],
];

const TOOLS_BUTTON_SELECTOR = TOOLS_BUTTON_ATTRIBUTES.map(([name, value]) => `[${name}=${value}]`).join(",");

function handleToolsButton(button)
{
    console.debug("“Tools” button found, activating the “Tools” menu...");

    clearTimeout(observerTimeout);
    observer.disconnect();

    const interval = setInterval(() =>
    {
        if (button.getAttribute("aria-expanded") === "true")
        {
            console.debug("“Tools” menu activated, congration!");

            clearTimeout(activateTimeout);
            clearInterval(interval);
        }
        else
        {
            button.click();
        }
    }, 250);

    const activateTimeout = setTimeout(() =>
    {
        console.debug("“Tools” menu not opened, aborting...");
        clearInterval(interval);
    }, 120000);
}

const observer = new MutationObserver((records) =>
{
    for (const record of records)
    {
        for (const node of record.addedNodes)
        {
            if (node instanceof Element)
            {
                if (TOOLS_BUTTON_ATTRIBUTES.some(([name, value]) => (node.getAttribute(name) === value)))
                {
                    handleToolsButton(node);
                }
                else
                {
                    const button = node.querySelector(TOOLS_BUTTON_SELECTOR);
                    if (button)
                    {
                        handleToolsButton(button);
                    }
                }
            }
        }
    }
});

observer.observe(document.body, { subtree: true, childList: true });
const observerTimeout = setTimeout(() =>
{
    console.debug("“Tools” button still not exist, aborting...");
    observer.disconnect();
}, 120000);

const button = document.querySelector(TOOLS_BUTTON_SELECTOR);
if (button)
{
    handleToolsButton(button);
}
else
{
    console.debug("“Tools” button not exist, attempting the MutationObserver method...");
}