google_search_keyboard_navigation.user.js

// ==UserScript==
// @name         Google Search Keyboard Navigation
// @namespace    http://tampermonkey.net/
// @version      0.7
// @description  Navigate Google search results using 'j' (down), 'k' (up), and Enter (open) keys
// @author       Your name
// @match        https://www.google.com/search?*
// @grant        GM_addStyle
// @downloadURL  https://gist.github.com/udaken/72334ce6086a47eb746fa3a6a8cc777a/raw/google_search_keyboard_navigation.user.js
// @updateURL  https://gist.github.com/udaken/72334ce6086a47eb746fa3a6a8cc777a/raw/google_search_keyboard_navigation.user.js
// ==/UserScript==

(function() {
    'use strict';

    // CSSスタイルを追加
    GM_addStyle(`
        div.g[tabindex="-1"]:focus {
            outline: none;
            background-color: #E8F0FE !important;
            border-radius: 4px;
        }
        div.g[tabindex="-1"]:focus * {
            background-color: transparent !important;
        }
    `);

    let currentIndex = -1;
    const searchResults = [];

    function initializeSearchResults() {
        // Google検索結果の要素を取得し、tabindex属性を追加
        const results = document.querySelectorAll('div.g');
        searchResults.length = 0;
        results.forEach(result => {
            result.setAttribute('tabindex', '-1');
            searchResults.push(result);
        });
    }

    function focusResult(index) {
        // 現在の結果からフォーカスを外す
        if (currentIndex >= 0 && currentIndex < searchResults.length) {
            searchResults[currentIndex].blur();
        }
        
        // 新しい結果にフォーカス
        if (index >= 0 && index < searchResults.length) {
            const resultElement = searchResults[index];
            resultElement.focus();
            resultElement.scrollIntoView({
                behavior: 'smooth',
                block: 'center'
            });
        }
    }

    function moveToNextResult() {
        if (searchResults.length === 0) {
            initializeSearchResults();
        }
        
        currentIndex++;
        if (currentIndex >= searchResults.length) {
            currentIndex = 0;
        }
        
        focusResult(currentIndex);
    }

    function moveToPreviousResult() {
        if (searchResults.length === 0) {
            initializeSearchResults();
        }
        
        currentIndex--;
        if (currentIndex < 0) {
            currentIndex = searchResults.length - 1;
        }
        
        focusResult(currentIndex);
    }

    function openCurrentResult(event) {
        if (currentIndex >= 0 && currentIndex < searchResults.length) {
            const link = searchResults[currentIndex].querySelector('a');
            if (link) {
                if (event.ctrlKey) {
                    window.open(link.href, '_blank');
                } else {
                    window.location.href = link.href;
                }
            }
        }
    }

    // 最初の結果を選択する
    function selectFirstResult() {
        if (currentIndex === -1 && searchResults.length > 0) {
            currentIndex = 0;
            focusResult(currentIndex);
        }
    }

    // キーボードイベントリスナーを追加
    document.addEventListener('keydown', function(e) {
        // 入力フィールドやテキストエリアでの入力時は動作しないようにする
        if (document.activeElement.tagName === 'INPUT' || document.activeElement.tagName === 'TEXTAREA') {
            return;
        }

        // Alt と組み合わせた場合は動作しない
        if (e.altKey || e.shiftKey || e.ctrlKey) {
            return;
        }

        switch (e.key) {
            case 'j':
                moveToNextResult();
                e.preventDefault();
                break;
            case 'k':
                moveToPreviousResult();
                e.preventDefault();
                break;
            case 'v':
                if (currentIndex !== -1) {
                    openCurrentResult(e);
                    e.preventDefault();
                }
                break;
        }
    });

    // ページロード時の初期化
    function initialize() {
        initializeSearchResults();
        selectFirstResult();
    }

    // ページロード時に初期化
    initialize();

    // 動的に結果が追加される可能性があるため、定期的に結果を更新
    const observer = new MutationObserver(() => {
        initializeSearchResults();
    });
    
    observer.observe(document.body, {
        childList: true,
        subtree: true
    });
})();