Redesign the post meta layout

- posted date
- updated date
- read time
- license statement of post bottom
- also refactor the `timeago.js`

_javascript/utils/timeago.js

@@ -3,11 +3,8 @@
  */
 
 $(function() {
-
   const timeagoElem = $(".timeago");
-
-  let toRefresh = timeagoElem.length;
-
+  let tasks = timeagoElem.length;
   let intervalId = void 0;
 
   const dPrompt = $("meta[name=day-prompt]").attr("content");
@@ -15,20 +12,19 @@ $(function() {
   const minPrompt = $("meta[name=minute-prompt]").attr("content");
   const justnowPrompt = $("meta[name=justnow-prompt]").attr("content");
 
-  function timeago(isoDate, dateStr) {
+  function timeago(date, initDate) {
     let now = new Date();
-    let past = new Date(isoDate);
+    let past = new Date(date);
 
     if (past.getFullYear() !== now.getFullYear()
         || past.getMonth() !== now.getMonth()) {
-      return dateStr;
+      return initDate;
     }
 
     let seconds = Math.floor((now - past) / 1000);
 
     let day = Math.floor(seconds / 86400);
     if (day >= 1) {
-      toRefresh -= 1;
       return ` ${day} ${dPrompt}`;
     }
 
@@ -47,22 +43,30 @@ $(function() {
 
   function updateTimeago() {
     $(".timeago").each(function() {
-      if ($(this).children("i").length > 0) {
-        let dateStr = $(this).clone().children().remove().end().text();
-        let node = $(this).children("i");
-        let iosDate = node.text(); /* ISO Date: "YYYY-MM-DDTHH:MM:SSZ" */
-        $(this).text(timeago(iosDate, dateStr));
-        $(this).append(node);
+      if ($(this)[0].hasAttribute("date") === false) {
+        tasks -= 1;
+        return;
       }
+
+      let date = $(this).attr("date");
+      let initDate = $(this).text();
+      let relativeDate = timeago(date, initDate);
+
+      if (relativeDate === initDate) {
+        $(this).removeAttr("date");
+      } else {
+        $(this).text(relativeDate);
+      }
+
     });
 
-    if (toRefresh === 0 && typeof intervalId !== "undefined") {
+    if (tasks === 0 && typeof intervalId !== "undefined") {
       clearInterval(intervalId); /* stop interval */
     }
-    return toRefresh;
+    return tasks;
   }
 
-  if (toRefresh === 0) {
+  if (tasks === 0) {
     return;
   }