Search Anywhere

search-anywhere.user.js

// ==UserScript==
// @name         Search Anywhere
// @namespace    http://tampermonkey.net/
// @version      INITIAL
// @description  Press Alt+D to activate search function within a webpage, Press Alt+D,D(Double Tap) for default browser behavior.
// @author       tez
// @include http://*/*
// @include https://*/*
// @grant        none
// ==/UserScript==

(function() {
    'use strict';
    var main = (function() {
        var isActive = false;

        var searchElementQueries = ['[type="search"]', '[name*="search"]', '[id*="search"]', '[placeholder*=search]', '[name*="Search"]', '[id*="Search"]', '[placeholder*=Search]', '[name*="query"]', '[name*="Query"]', '[id*="query"]', '[id*="Query"]', '[name=q]', '[class*=search]', '[class*=Search]', '[name*=keyword]', '[name*=Keyword]'];

        function focusSearchBar() {
            var searchBarElement;

            function focusCaretEnd(el) {
                el.selectionStart = el.selectionEnd = el.value.length;
            }

            var candidate;
            var currWidth = 0;
            var maxWidth = 0;

            for (var query of searchElementQueries) {
                candidate = document.querySelector('input'+query);
                if (candidate) {
                    currWidth = candidate.getBoundingClientRect().width
                    if (currWidth > maxWidth) {
                        maxWidth = currWidth;
                        searchBarElement = candidate;
                    }
                }
            }

            if (searchBarElement && maxWidth > 0) {

                    searchBarElement.focus();
                    setTimeout(focusCaretEnd, 0, searchBarElement);
            }

            return !!searchBarElement;
        }

        function rightKeysPressed(e) {
            return e.altKey && e.key == 'd';
        }

        function eventHandler(e) {
            if (isActive = rightKeysPressed(e) && !isActive) {
                if (focusSearchBar()) {
                    e.preventDefault();
                    e.stopPropagation();
                }
            }
        }

        function registerEvent() {
            document.onkeydown = eventHandler;
            document.onkeyup = function(e) {
                isActive = rightKeysPressed(e);
            };
        }

        return registerEvent;
    })();

    document.addEventListener('DOMContentLoaded', main);
})();