Javascript：单击某些元素时触发弹出窗口

Question

下面是我在网站上使用的流行代码。我不懂javascript，所以我不太了解代码，但是它可能会设置cookie并在窗口上方创建某种层，单击该层会启动弹出窗口。我仅在单击某些元素的图像和链接时才需要触发弹出窗口（仅绑定到HREFS）。任何想法如何修改代码？预先感谢。

<script type="text/javascript">
  var acx_today = new Date();
  expires_date = new Date(acx_today.getTime() + (60 60 1000));
  if (navigator.cookieEnabled) {
    var pop_under = null;
    var pop_cookie_name = "acx_popunder";
    var pop_timeout = 1320;

    function pop_cookie_enabled() {
      var is_enabled = false;
      if (!window.opera && !navigator.cookieEnabled) return is_enabled;
      if (typeof document.cookie == 'string')
        if (document.cookie.length == 0) {
          document.cookie = "test";
          is_enabled = document.cookie == 'test';
          document.cookie = '';
        }
      else {
        is_enabled = true;
      }
      return is_enabled;
    }

    function pop_getCookie(name) {
      var cookie = " " + document.cookie;
      var search = " " + name + "=";
      var setStr = null;
      var offset = 0;
      var end = 0;
      if (cookie.length > 0) {
        offset = cookie.indexOf(search);
        if (offset != -1) {
          offset += search.length;
          end = cookie.indexOf(";", offset);
          if (end == -1) {
            end = cookie.length;
          }
          setStr = unescape(cookie.substring(offset, end));
        }
      }
      return (setStr);
    }

    function pop_setCookie(name, value) {
      document.cookie = name + "=" + escape(value) + "; expires=" + expires_date.toGMTString() + "; path=/;";
    }

    function show_pop() {
      var pop_wnd = "https://www.somesite.com";
      var fea_wnd = "scrollbars=1,resizable=1,toolbar=1,location=1,menubar=1,status=1,directories=0";
      var need_open = true;
      if (document.onclick_copy != null) document.onclick_copy();
      if (document.body.onbeforeunload_copy != null) document.body.onbeforeunload_copy();
      if (pop_under != null) {
        if (!pop_under.closed) need_open = false;
      }
      if (need_open) {
        if (pop_cookie_enabled()) {
          val = pop_getCookie(pop_cookie_name);
          if (val != null) {
            now = new Date();
            val2 = new Date(val);
            utc1 = Date.UTC(now.getFullYear(), now.getMonth(), now.getDate(), now.getHours(), now.getMinutes(), now.getSeconds());
            utc2 = Date.UTC(val2.getFullYear(), val2.getMonth(), val2.getDate(), val2.getHours(), val2.getMinutes(), val2.getSeconds());
            if ((utc1 - utc2) / 1000 < pop_timeout * 60) {
              need_open = false;
            }
          }
        }
      }

      if (need_open) {
        under = window.open(pop_wnd, "", fea_wnd);
        under.blur();
        window.focus();
        if (pop_cookie_enabled()) {
          now = new Date();
          pop_setCookie(pop_cookie_name, now);
        }
      }
    }

    function pop_init() {
      var ver = parseFloat(navigator.appVersion);
      var ver2 = (navigator.userAgent.indexOf("Windows 95") >= 0 || navigator.userAgent.indexOf("Windows 98") >= 0 || navigator.userAgent.indexOf("Windows NT") >= 0) && (navigator.userAgent.indexOf('Opera') == -1) && (navigator.appName != 'Netscape') && (navigator.userAgent.indexOf('MSIE') > -1) && (navigator.userAgent.indexOf('SV1') > -1) && (ver >= 4);
      if (ver2) {
        if (document.links) {
          for (var i = 0; i < document.links.length; i++) {
            if (document.links[i].target != "_blank") {
              document.links[i].onclick_copy = document.links[i].onclick;
              document.links[i].onclick = show_pop;
            }
          }
        }
      }
      document.onclick_copy = document.onclick;
      document.onmouseup = show_pop;
      return true;
    }

    pop_init();
  }
</script>