Image onMouseHover arch.b4k

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Image onMouseHover arch.b4k

Mouse over images to view full size
当前为 2021-04-03 提交的版本，查看最新版本。
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// ==UserScript==
// @name        Image onMouseHover arch.b4k
// @namespace   Zero_G@4d7d460c-0424-11eb-adc1-0242ac120002
// @description Mouse over images to view full size
// @include     *://arch.b4k.co/*/thread/*
// @version     1.3
// @grant       none
// ==/UserScript==

(function(){
  // Set this const to false if you don't want to change the place of the image file name.
  const changePlaceOfImageFilename = true;
  
  // Create image-video containers and append them
  var imageContainer = document.createElement('div');
  var videoContainer = document.createElement('div');
  var videoTag = document.createElement('video');
  document.body.appendChild(imageContainer);
  document.body.appendChild(videoContainer);
  videoContainer.appendChild(videoTag);
  
  // Possition them a top right of current scroll
  imageContainer.style.position = 'fixed';
  imageContainer.style.top = '0em';
  imageContainer.style.right = '0em';
  videoContainer.style.position = 'fixed';
  videoContainer.style.top = '0em';
  videoContainer.style.right = '0em';
  
  // Hide containters
  imageContainer.style.visibility = 'hidden';
  videoContainer.style.visibility = 'hidden';
  
  // Prevent image-video from being bigger than screen
  imageContainer.style.height = '100%';
  videoContainer.style.height = '100%';
  videoTag.style.maxHeight = '100%';
  
  // Wait for document to load
  document.addEventListener("DOMContentLoaded", function(){
   // Create event listeners
    const imageLinks = document.getElementsByClassName('thread_image_link');
    Array.from(imageLinks).forEach(function(element) {
      element.addEventListener('mouseover', enlargeImage, false);
      // Hide image container
      element.addEventListener('mouseout', clear, false);
    });
    
    // Change position of image name to atop of image thumb
    if(changePlaceOfImageFilename){
      const imageNameList = document.getElementsByClassName('post_file_filename');
      Array.from(imageNameList).forEach(function(element) {
        // Add inside image div (not used)
        //element.parentNode.parentNode.childNodes[3].prepend(element);
        //element.style.display = 'block';
        // Create div and add it before image div
        let div = document.createElement('div');
        let span = document.createElement('span');
        let wrapper = element.parentNode.parentNode;
        div.className = 'post_file';
        span.textContent = 'File: ';
        span.style.paddingLeft = '0.5em';
        div.appendChild(span);
        div.appendChild(element);
        wrapper.insertBefore(div, wrapper.getElementsByClassName('thread_image_box')[0])
      });
    }
    
    // Attach mutation observers
    Array.from(postToObserve).forEach(function(element) {
      observer.observe(element, {childList: true, attributes: false, subtree: true});
    });
  });
  
  function enlargeImage(event){
    if(/\.webm$/.test(event.currentTarget.href)){
      // If it's a video
      if (videoTag.src !== event.currentTarget.href){
        videoTag.src = '';
        videoTag.src = event.currentTarget.href;
      }
      videoContainer.style.visibility = 'visible';
      videoTag.play();
    }else{
      // If it's an image
      // Get post Id
      let id = event.currentTarget.parentNode.parentNode.parentNode.id;
      // Get image tag if exists
      let imgTag = imageContainer.querySelector('#i'+id);
      
      if(imgTag){
        imgTag.style.display = 'block';
      } else {
        imgTag = createImgTag(id, event.currentTarget.href);
        imageContainer.appendChild(imgTag);
      }

      imageContainer.style.visibility = 'visible';
    }
  }
  
  function clear(event){
    imageContainer.style.visibility = 'hidden';
    videoContainer.style.visibility = 'hidden';
    
    // Hide imgTag
    let id = event.currentTarget.parentNode.parentNode.parentNode.id;
    imageContainer.querySelector('#i'+id).style.display = 'none';
    
    // Stop video
    videoTag.pause();
    videoTag.currentTime = 0;
  }
  
  function createImgTag(id, src){
    var imgTag = document.createElement('img');
    imgTag.style.maxHeight = '100%';
    imgTag.style.display = 'block';
    imgTag.id = 'i' + id;
    imgTag.src = src;
    
    return imgTag;
  }
  
  // Support for inline quotes (http://greasyfork.icu/en/scripts/424112-inline-quote-links-arch-b4k-co)
  // Add mutation observers to all posts, then when an inline is detected add event listeners to image link
  var postToObserve = document.getElementsByClassName('text');
  const observer = new MutationObserver(function(mutationsList, observer){
    for(const mutation of mutationsList) {
      if(typeof(mutation.addedNodes[0]) != "undefined" && typeof(mutation.addedNodes[0].id) != "undefined"){
        if(mutation.addedNodes[0].id.includes('inline')){
          let imageLink = mutation.addedNodes[0].querySelector('.thread_image_link');

          if (imageLink){
            imageLink.addEventListener('mouseover', enlargeImage, false);
            imageLink.addEventListener('mouseout', clear, false);
          }
        }
      }
    }
  });
})()