Smart Scroll to Top Button

Smart Smooth scroll-to-top button that can be dragged to reposition and auto-hide

K instalaci tototo skriptu si budete muset nainstalovat rozšíření jako Tampermonkey, Greasemonkey nebo Violentmonkey.

You will need to install an extension such as Tampermonkey to install this script.

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Violentmonkey.

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Userscripts.

You will need to install an extension such as Tampermonkey to install this script.

K instalaci tohoto skriptu si budete muset nainstalovat manažer uživatelských skriptů.

(Už mám manažer uživatelských skriptů, nechte mě ho nainstalovat!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(Už mám manažer uživatelských stylů, nechte mě ho nainstalovat!)

// ==UserScript==
// @name         Smart Scroll to Top Button
// @namespace    U2Nyb2xsIHRvIFRvcCBCdXR0b24
// @version      1.0
// @description  Smart Smooth scroll-to-top button that can be dragged to reposition and auto-hide
// @author       smed79
// @license      GPLv3
// @icon         https://i25.servimg.com/u/f25/11/94/21/24/scroll10.png
// @run-at       document-end
// @match        https://*/*
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    // Create the button element
    const button = document.createElement('div');
    button.id = 'scroll-to-top-btn';
    button.innerHTML = '↑';
    
    // Style the button
    const style = document.createElement('style');
    style.textContent = `
        #scroll-to-top-btn {
            position: fixed;
            bottom: 25px;
            right: 25px;
            width: 48px;
            height: 48px;
            border-radius: 50%;
            background-color: rgba(0, 0, 0, 0.5);
            color: white;
            font-size: 24px;
            display: flex;
            align-items: center;
            justify-content: center;
            cursor: pointer;
            opacity: 0;
            visibility: hidden;
            transition: opacity 0.3s ease, visibility 0.3s ease, background-color 0.3s ease;
            box-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
            z-index: 9999;
            user-select: none;
            touch-action: none;
        }

        #scroll-to-top-btn:hover {
            background-color: rgba(0, 0, 0, 0.8);
            box-shadow: 0 6px 12px rgba(0, 0, 0, 0.4);
        }

        #scroll-to-top-btn.show {
            opacity: 0.8;
            visibility: visible;
        }

        #scroll-to-top-btn.dragging {
            cursor: grabbing;
            background-color: rgba(0, 0, 0, 0.9);
        }
    `;
    document.head.appendChild(style);
    document.body.appendChild(button);

    let isDragging = false;
    let touchStartTime = 0;
    let hideTimeout;

    // Calculate 15% of page height
    function get15PercentScroll() {
        const documentHeight = document.documentElement.scrollHeight - window.innerHeight;
        return documentHeight * 0.15;
    }

    // Hide button after 3 seconds of inactivity
    function resetHideTimer() {
        clearTimeout(hideTimeout);
        hideTimeout = setTimeout(() => {
            if (!isDragging) {
                button.classList.remove('show');
            }
        }, 3000);
    }

    // Show/hide button based on scroll position
    window.addEventListener('scroll', function() {
        const scrollThreshold = get15PercentScroll();
        const currentScroll = window.scrollY;

        if (currentScroll > scrollThreshold) {
            button.classList.add('show');
            resetHideTimer();
        } else {
            button.classList.remove('show');
            clearTimeout(hideTimeout);
        }
    });

    // Show button on mouse/touch movement
    document.addEventListener('mousemove', function() {
        if (button.classList.contains('show') && !isDragging) {
            resetHideTimer();
        }
    });

    document.addEventListener('touchmove', function() {
        if (button.classList.contains('show') && !isDragging) {
            resetHideTimer();
        }
    });

    // Smooth scroll to top on button click
    button.addEventListener('click', function() {
        if (!isDragging) {
            window.scrollTo({
                top: 0,
                behavior: 'smooth'
            });
        }
    });

    // Handle drag on mouse
    button.addEventListener('mousedown', function(e) {
        touchStartTime = Date.now();
    });

    button.addEventListener('mousemove', function(e) {
        if (touchStartTime && Date.now() - touchStartTime > 300) {
            isDragging = true;
            button.classList.add('dragging');
            clearTimeout(hideTimeout);
        }
    });

    document.addEventListener('mousemove', function(e) {
        if (isDragging) {
            button.style.bottom = (window.innerHeight - e.clientY) + 'px';
            button.style.right = (window.innerWidth - e.clientX) + 'px';
        }
    });

    document.addEventListener('mouseup', function() {
        if (isDragging) {
            isDragging = false;
            button.classList.remove('dragging');
            resetHideTimer();
        }
        touchStartTime = 0;
    });

    // Handle drag on touch
    button.addEventListener('touchstart', function(e) {
        touchStartTime = Date.now();
    });

    document.addEventListener('touchmove', function(e) {
        if (touchStartTime && Date.now() - touchStartTime > 300 && button.classList.contains('show')) {
            isDragging = true;
            button.classList.add('dragging');
            clearTimeout(hideTimeout);
            const touch = e.touches[0];
            button.style.bottom = (window.innerHeight - touch.clientY) + 'px';
            button.style.right = (window.innerWidth - touch.clientX) + 'px';
        }
    });

    document.addEventListener('touchend', function() {
        if (isDragging) {
            isDragging = false;
            button.classList.remove('dragging');
            resetHideTimer();
        }
        touchStartTime = 0;
    });

    // Recalculate threshold on window resize
    window.addEventListener('resize', function() {
        get15PercentScroll();
    });
})();