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zhihu-reply-tip

显示被引用的用户的最近一条评论

  1. // ==UserScript==
  2. // @name       zhihu-reply-tip
  3. // @namespace  https://github.com/QingYun/
  4. // @version    0.1
  5. // @description  显示被引用的用户的最近一条评论
  6.  // @match      http://www.zhihu.com/*
  7. // @copyright  2012+, QingYun
  8. // ==/UserScript==
  9.  
  10. var HIDE_STYLE = "display: none";
  11.  
  12. function hasClass(node, className) {
  13. 	return node && node.classList && node.classList.contains(className);
  14. }
  15.  
  16. function createReplyTipNode() {
  17.     var a = document.createElement("a");
  18.     a.setAttribute("href", "#");
  19.     a.setAttribute("class", "like zm-comment-op-link");
  20.     
  21.     var i = document.createElement("i");
  22.     i.setAttribute("class", "zg-icon zg-icon-comment-reply");
  23.     
  24.     a.appendChild(i);
  25.     a.appendChild(document.createTextNode("查看 TA 的最近一条评论"));
  26.     
  27.     return a;
  28. }
  29.  
  30. function createQuoteBlockNode(content) {
  31. 	var bq = document.createElement("blockquote");
  32.     bq.setAttribute("style", HIDE_STYLE);
  33.     
  34.     var p = document.createElement("p");
  35.     p.appendChild(document.createTextNode(content));
  36.     
  37.     bq.appendChild(p);
  38.     
  39.     return bq;
  40. }
  41.  
  42. function latestReply(commentItems, userLookingFor, endIndex) {
  43.     for (var i = endIndex - 1; i >= 0 ; i--) {
  44.         var curUser = commentItems[i].querySelector(".zg-link").textContent;
  45.         if (curUser ==  userLookingFor) {
  46.             return commentItems[i].querySelector(".zm-comment-content").textContent;
  47.         }
  48.     }
  49. }
  50.  
  51. function addOneReplyTip(commentItems, targetIndex) {
  52.     var curItem = commentItems[targetIndex];
  53.     if (curItem.querySelector(".zm-comment-hd .like") !== null) 
  54.         return ;
  55.     
  56.     var headNode = curItem.querySelector(".zm-comment-hd");
  57.     if (headNode.childNodes.length > 3) {
  58.         var referredUser;
  59.         if (headNode.firstChild.nodeValue == "\n 匿名用户")
  60.             referredUser = headNode.querySelectorAll(".zg-link")[0];
  61.         else
  62.             referredUser = headNode.querySelectorAll(".zg-link")[1];
  63.         
  64.         if (referredUser) {
  65.             var referredReply = latestReply(commentItems, referredUser.textContent, targetIndex);
  66.             if (!referredReply)
  67.                 return ;
  68.             
  69.             var q = null;
  70.             var replyTip = createReplyTipNode();
  71.             replyTip.addEventListener("click", function() {
  72.                 if (q === null) {
  73.                     q = createQuoteBlockNode(referredReply);
  74.                     var content = curItem.querySelector(".zm-comment-content");
  75.                     content.parentNode.insertBefore(q, content);
  76.                 }
  77.                 
  78.                 if (q.getAttribute("style") == HIDE_STYLE)
  79.                     q.removeAttribute("style");
  80.                 else
  81.                     q.setAttribute("style", HIDE_STYLE);
  82.             });
  83.             
  84.             curItem.querySelector(".zm-comment-hd").appendChild(replyTip);
  85.         }
  86.     }
  87. }
  88.  
  89. function addReplyTips(commentList) {
  90.     var commentItems = commentList.querySelectorAll(".zm-item-comment");
  91.     for (var i = 0; i < commentItems.length; i++) {
  92.         addOneReplyTip(commentItems, i);
  93.     }
  94. }
  95.  
  96. (function(){
  97.     var addReplyTipTimer;
  98.     var observer = new MutationObserver(function(mutations) {
  99.         mutations.forEach(function(mutation) {
  100.             if (mutation.type == "childList") {
  101.                 var firstAddedNode = mutation.addedNodes.length && mutation.addedNodes[0];
  102.                 var firstRemovedNode = mutation.removedNodes.length && mutation.removedNodes[0];
  103.                 
  104.                 if (hasClass(firstAddedNode, "zm-comment-box") && hasClass(firstRemovedNode, "zm-comment-box"))
  105.                     addReplyTips(mutation.addedNodes[0].querySelector(".zm-comment-list"));
  106.                 else if (hasClass(firstAddedNode, "zm-item-comment")) {
  107.                 	if (addReplyTipTimer) clearTimeout(addReplyTipTimer);
  108.                     addReplyTipTimer = setTimeout(function() {
  109.                     	addReplyTips(mutation.target);
  110.                     }, 100);
  111.                 }
  112.             }
  113.         });
  114.     });
  115.     
  116.     observer.observe(document.body, {
  117.         childList: true
  118.         , subtree: true
  119.         , attributes: false
  120.         , characterData: false
  121.     });
  122. })();