HackerNews "Who is Hiring" Search w/ Date Sorting

hn_search_with_sort.js

function query() {
  var SORT_RECENT_FIRST = true;
  var SEARCH_REPLIES = true;

  var query_list = Array.prototype.slice.call(arguments);

  var commentTable = document.querySelector('.comment-tree');
  var commentNodes = Array.prototype.slice.call(commentTable.querySelectorAll('.athing'));

  var COMMENT_TEXT_SELECTOR = '.c5a,.cae,.c00,.c9c,.cdd,.c73,.c88';

  var DEPTH_SELECTOR = '.ind img',
      DATE_SELECTOR = '.age a',
      DEPTH_LIMIT = 40,
      DATE_REGEX = /id=(\d+)/i;

  // If we have a RegEx, return it
  // Otherwise make it a case insensitive regex.
  function destring(what) {
    return what.test ? what : new RegExp(what.toString(), 'i');
  }

  var Comment = function(node, index) {
    var depth = node.querySelector(DEPTH_SELECTOR);
    var text = node.querySelectorAll(COMMENT_TEXT_SELECTOR);
    var date = node.querySelector(DATE_SELECTOR);

    date = (date && date.href) ? date.href.match(DATE_REGEX) : [];
    this.date = (typeof date[1] !== 'undefined') ? +date[1] : 0;

    this.depth = (depth && depth.width) ? +(depth.width) : 0;
    this.text = (text && text.length) ? text[0].innerHTML.trim() : '';
    this.childText = '';

    this.nodes = [node];
  };

  Comment.prototype.display = function(state) {
    this.nodes.forEach(function(node) {
      node.style.display = state;
    });
  };

  Comment.prototype.search = function(query_list) {
    var self = this;

    return query_list.some(function(query) {
      if (query.forEach) {
        return query.map(destring).some(function(query) {
          return self.single_query_search(query);
        });
      } else {
        query = destring(query);
        return self.single_query_search(query);
      }
    });
  };

  Comment.prototype.single_query_search = function(destringed_query) {
    if (this.text.search(destringed_query) > 1) {
      return true;
    }
    if (SEARCH_REPLIES) {
      return this.childText.search(destringed_query) > -1;
    }
    return false;
  };

  var groupedComments = function() {
    var grouped = [];
    var comment = {};
    var lastRoot = {};

    commentNodes.forEach(function(node, index) {
      comment = new Comment(node, index);

      if (comment.depth < DEPTH_LIMIT) {
        grouped.push(comment);
        lastRoot = comment;
      } else {
        lastRoot.nodes.push(node);
        lastRoot.childText += comment.text;
      }
    });

    return grouped;
  };

  var sortedTbody = document.createElement('tbody');
  var sortedComments = groupedComments().sort(function(a, b) {
    return (a.date > b.date) ? -1 : 1;
  });

  var shown = 0, total = sortedComments.length;

  sortedComments.forEach(function(comment) {
    if (comment.search(query_list)) {
      shown++;
      comment.display('block');
    } else {
      comment.display('none');
    }

    comment.nodes.forEach(function(node) {
      sortedTbody.appendChild(node);
    });
  });

  // Remove the existing tbody
  while(commentTable.lastChild) {
    commentTable.removeChild(commentTable.lastChild);
  }

  commentTable.appendChild(sortedTbody);

  return {shown: shown, total: total}
}