[Global] Image Zoomer

Allows zooming into images without changing pages. Hold Ctrl+Shift (Cmd+Shift on MAC) when clicking on an image to load it with the extension.

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

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

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

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

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

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

(I already have a user script manager, let me install it!)

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.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name         [Global] Image Zoomer
// @description	 Allows zooming into images without changing pages. Hold Ctrl+Shift (Cmd+Shift on MAC) when clicking on an image to load it with the extension.
// @author       MetalTxus
// @version      1.3.9

// @include      *
// @exclude      *youtube.com/embed*

// @icon         https://dl.dropbox.com/s/4mnevtuyvt1eden/48.png
// @require      http://code.jquery.com/jquery-3.2.1.min.js
// @require      https://greasyfork.org/scripts/396703-key-navigation/code/Key%20navigation.js
// @namespace    https://greasyfork.org/users/8682
// ==/UserScript==

const ENABLED_FOR_LINKS = true;
const preloader = 'https://dl.dropbox.com/s/xbxkvw77dfsrum4/preloader.svg';
const extensions = ['.jpg', '.jpeg', '.png', '.gif'];

const jQuery = window.jQuery;
const setUpKeyNavigation = window.setUpKeyNavigation;

const gizContainer = jQuery(`<div id="giz-container">`);
const gizAnchor = jQuery(`<a target="_blank" id="giz-link">`);
const gizImage = jQuery(`<img class="centered" id="giz-image">`);
const gizPreloader = jQuery(`<img class="centered" id="giz-preloader" src="${preloader}">`);
const gizClose = jQuery(`<span id="giz-close">`);

const initialize = () => {
  jQuery(`<style>
       #giz-container              { position: fixed; top: 0; left: 0; height: 100%; width: 100%; background-color: rgba(0, 0, 0, .9); z-index: 10000; display: none; }
       #giz-container .centered    { position: fixed; left: 50%; top: 50%; }
       #giz-preloader              { margin-left: -32px; margin-top: -33px; z-index: 10001; filter: drop-shadow(0 0 2px rgba(255, 255, 255, 1)); }
       #giz-image                  { max-height: 100%; max-width: 100%; cursor: url(https://dl.dropbox.com/s/32kv0rup3zw5lho/zoom-in.cur), zoom-in; }
       #giz-close                  { width: 32px; height: 32px; right: 0; margin: 4px; position: absolute; display: block; cursor: pointer; background: url(https://dl.dropbox.com/s/7smpm0ohq2ymfey/close.svg); }
     </style>`).appendTo('head');

  gizContainer.click(hideContainer);
  gizClose.click(hideContainer);

  gizAnchor.append(gizImage);
  gizContainer.append(gizAnchor);
  gizContainer.append(gizPreloader);
  gizContainer.append(gizClose);

  jQuery('body').append(gizContainer);

  gizImage
    .on('load', event => {
      const newUrl = event.target.src;
      gizAnchor.attr('href', newUrl);
      showImage();
    })
    .on('error', () => {
      const url = gizImage.attr('src');

      for (var i = 0; i < extensions.length; i++) {
        if (url.includes(extensions[i])) {
          const newUrl = url.replace(extensions[i], extensions[i + 1]);
          gizImage.attr('src', newUrl);
          break;
        }
      }
    });

  jQuery(document).click(event => {
    if (
      (event.ctrlKey || event.metaKey) &&
      event.shiftKey &&
      event.target.nodeName.toLowerCase() === 'img' &&
      (ENABLED_FOR_LINKS || event.parentElement.target.nodeName !== 'A')
    ) {
      event.preventDefault();
      loadPreview(event.target);
    }
  });

  jQuery(window).resize(() => {
    if (gizContainer.is(':visible')) {
      relocateImage();
    }
  });

  setUpKeyNavigation({
    onLeftPressed: e => isContainerVisible() && loadSiblingImage(-1) && e.preventDefault(),
    onRightPressed: e => isContainerVisible() && loadSiblingImage(1) && e.preventDefault(),
    onDownPressed: e => isContainerVisible() && hideContainer() && e.preventDefault(),
    onUpPressed: e => isContainerVisible() && e.preventDefault(),
  });

  console.info('Script "Global Image Zoomer" ready for its use');
};

const loadPreview = element => {
  let newURL = element.src;

  if (newURL !== undefined && element.nodeName === 'IMG') {
    newURL = parseURL(newURL);

    if (removeExtension(newURL) !== removeExtension(gizImage.attr('src')) && newURL !== preloader) {
      loadImageUrl(newURL);
    }

    showContainer();
  }
};

const loadImageUrl = newURL => {
  showPreloader();

  gizImage.attr('src', newURL);
  gizAnchor.attr('href', newURL);
};

const loadSiblingImage = increment => {
  if (!isContainerVisible()) return;

  const imagesUrls = [
      ...new Set(
          jQuery('img')
              .map((i, img) => img.src)
              .toArray()
      )
  ];
  const currentImageUrl = gizImage.attr('src');
  const currentIndex = imagesUrls.indexOf(currentImageUrl);
  const requestedIndex = currentIndex + increment;
  if (requestedIndex < 0 || requestedIndex >= imagesUrls.length) {
    hideContainer();
  }
  /*const newIndex = requestedIndex < 0 ? 0 : requestedIndex >= imagesUrls.length ? imagesUrls.length - 1 : requestedIndex;*/
  const newIndex = requestedIndex;
  loadImageUrl(imagesUrls[newIndex]);
};

const parseURL = url => {
  if (urlContains('deviantart.com')) {
    url = url.replace('/200H/', '/').replace('/150/', '/');
  } else if (urlContains('zerochan.net')) {
    url = url.replace('s3.', 'static.').replace('.240.', '.full.');
  }

  return url;
};

const urlContains = text => {
  return window.location.href.includes(text);
};

const removeExtension = url => {
  if (url) {
    extensions.forEach(extension => {
      url = url.replace(extension, '');
    });
  }
  return url;
};

const relocateImage = () => {
  return gizImage.css('margin', `${-Math.ceil(gizImage.height() / 2)}px ${-Math.ceil(gizImage.width() / 2)}px`);
};

const hideContainer = () => {
  return gizContainer.fadeOut(100);
};
const showContainer = () => {
  return gizContainer.fadeIn(100);
};
const isContainerVisible = () => {
  return !jQuery('#giz-container').is(':hidden');
}

const hidePreloader = () => {
  return gizPreloader.hide();
};
const showPreloader = () => {
  return hideImage() && gizPreloader.show();
};

const hideImage = () => {
  return gizImage.hide();
};
const showImage = () => {
  return relocateImage() && hidePreloader() && gizImage.show();
};

setTimeout(() => {
  if (!jQuery('#giz-container').length) {
    initialize();
  }
});