☰

Gallery Scroll Navigator

Automatically navigate to the next page when scrolling to the bottom of image gallery websites. Optimized for Hitomi and Pixiv.

Fra og med 20.09.2024. Se den nyeste version.

// ==UserScript==
// @name         Gallery Scroll Navigator
// @namespace    https://github.com/YukiteruDev
// @version      1.32
// @description  Automatically navigate to the next page when scrolling to the bottom of image gallery websites. Optimized for Hitomi and Pixiv.
// @author       Yukiteru
// @match        https://hitomi.la/*
// @match        https://www.pixiv.net/*
// @match        https://nhentai.net/*
// @match        https://exhentai.org/*
// @grant        GM_setValue
// @grant        GM_getValue
// @grant        GM_deleteValue
// @grant        GM_registerMenuCommand
// @grant        GM_unregisterMenuCommand
// @grant        GM_addValueChangeListener
// @require      https://greasyfork.org/scripts/470224-tampermonkey-config/code/Tampermonkey%20Config.js
// @license      MIT
// ==/UserScript==

(function() {
  'use strict';

  function printLog(message) {
    console.log(`[Scroll Pager]: ${message}`);
  }

  // Initialize the configuration
  const config_desc = {
    scrolls: {
      name: "Number of Scrolls to Next Page",
      processor: "int_range-1-10",
      value: 3, // Default value
    }
  };
  const config = new GM_config(config_desc);

  let scrollCounter = 0;
  let progressBarBottom;
  let progressBarTop;
  let disablePaging = false;

  // Function to create the progress bar element
  function createProgressBar(position = 'bottom') {
    const bar = document.createElement('div');
    bar.style.cssText = `
      position: fixed;
      left: 0;
      right: 0;
      height: 3px;
      background-color: red;
      z-index: 9999;
      transform-origin: center;
      transform: scaleX(0);
      transition: transform 0.3s ease;
      ${position === 'top' ? 'top' : 'bottom'}: 0;
    `;
    document.body.appendChild(bar);
    return bar;
  }

  const siteDict = {
    hitomi: {
      host: 'hitomi.la',
      getPageButton(direction) {
        try {
          const pageContainer = [...document.querySelectorAll('.page-container li')];
          const currentPage = pageContainer.filter(i => i.textContent !== '...').find(i => i.children.length === 0);
          const targetLi = direction === 'next' ? currentPage.nextElementSibling : currentPage.previousElementSibling;
          return targetLi ? targetLi.querySelector('a') : null;
        } catch(e) {
          return null;
        }
      }
    },
    pixiv: {
      host: 'www.pixiv.net',
      getPageButton(direction) {
        const selector = `nav:has(button) > a:${direction === 'next' ? 'last' : 'first'}-child`
        const pageButton = document.querySelector(selector);
        return pageButton && !pageButton.hasAttribute('hidden') ? pageButton : null;
      }
    },
    nhentai: {
      host: 'nhentai.net',
      getPageButton(direction) {
        const selector = direction === 'next' ? '.next' : '.previous'
        const pageButton = document.querySelector(selector);
        return pageButton || null;
      }
    },
    exhentai: {
      host: 'exhentai.org',
      getPageButton(direction) {
        const selector = direction === 'next' ? 'a#dnext' : 'a#dprev'
        const pageButton = document.querySelector(selector);
        return pageButton || null;
      }
    },
  };

  function getCurrentSite() {
    return Object.values(siteDict).find(site => location.host === site.host);
  }

  function getCurrentPosition() {
    return window.innerHeight + window.scrollY;
  }

  function loadNextPage() {
    printLog('Loading next page...');
    const site = getCurrentSite();
    const pageButton = site?.getPageButton('next');
    if (pageButton) pageButton.click();
  }

  function loadPrevPage() {
    printLog('Loading previous page...');
    const site = getCurrentSite();
    const pageButton = site?.getPageButton('prev');
    if (pageButton) pageButton.click();
  }

  function checkIsScrollingDown(event) {
    if (event.wheelDelta) {
      return event.wheelDelta < 0;
    }
    return event.deltaY > 0;
  }

  function updateProgressBar(progress, bar) {
    const maxScrolls = config.get('scrolls');
    const scale = Math.min(progress / maxScrolls, 1);
    bar.style.transform = `scaleX(${scale})`;
  }

  progressBarBottom = createProgressBar('bottom');
  progressBarTop = createProgressBar('top');

  function resetScrollProgress() {
    scrollCounter = 0;
    updateProgressBar(0, progressBarBottom);
    updateProgressBar(0, progressBarTop);
  }

  function checkIsBottom() {
    return (window.innerHeight + window.scrollY).toFixed() >= document.body.offsetHeight;
  }

  function checkIsTop() {
    return window.scrollY === 0;
  }

  function setWheelEvent() {
    if (location.host === 'nhentai.net') {
      // adjust nhentai's body height since it's fucked up
      const contentHeight = document.querySelector('#content').offsetHeight;
      document.body.style.height = `${contentHeight}px`;
    }

    document.addEventListener("wheel", event => {
      if (disablePaging) return;

      const isBottom = checkIsBottom();
      const isTop = checkIsTop();
      const isScrollingDown = checkIsScrollingDown(event);

      const site = getCurrentSite();

      const isPagingTop = isTop && !isScrollingDown && site.getPageButton('prev');
      const isPagingBottom = isBottom && isScrollingDown && site.getPageButton('next');

      if (isPagingTop || isPagingBottom) {
        scrollCounter++;
        const progressBar = isPagingTop ? progressBarTop : progressBarBottom;
        const loadPage = isPagingTop ? loadPrevPage : loadNextPage;

        updateProgressBar(scrollCounter, progressBar);
        printLog(`Scrolls at ${isPagingTop ? 'top' : 'bottom'}: ${scrollCounter}`);

        const maxScrolls = config.get('scrolls');
        if (scrollCounter >= maxScrolls) {
          disablePaging = true;
          resetScrollProgress();
          loadPage();
        }
        return;
      }

      resetScrollProgress();
    });
  }

  function checkPagination() {
    const site = getCurrentSite();
    if (!site) return;

    const pager = site.getPageButton('next') || site.getPageButton('prev');
    if (!pager) return;

    printLog('Pager detected');
    observer.disconnect();
    setWheelEvent();
  }

  const observer = new MutationObserver(() => checkPagination());
  observer.observe(document.body, { childList: true, subtree: true });

  window.navigation.addEventListener("navigate", () => disablePaging = false); // for ajax-paging sites
})();