(ref #519) Change datetime formats

src/main/scala/view/helpers.scala

@@ -1,5 +1,5 @@
 package view
-import java.util.{Date, TimeZone}
+import java.util.{Locale, Date, TimeZone}
 import java.text.SimpleDateFormat
 import play.twirl.api.Html
 import util.StringUtil
@@ -15,6 +15,49 @@ object helpers extends AvatarImageProvider with LinkConverter with RequestCache
    */
   def datetime(date: Date): String = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(date)
 
+  val timeUnits = List(
+    (1000L, "second"),
+    (1000L * 60, "minute"),
+    (1000L * 60 * 60, "hour"),
+    (1000L * 60 * 60 * 24, "day"),
+    (1000L * 60 * 60 * 24 * 30, "month"),
+    (1000L * 60 * 60 * 24 * 365, "year")
+  ).reverse
+
+  /**
+   * Format java.util.Date to "x {seconds/minutes/hours/days/months/years} ago"
+   */
+  def datetimeAgo(date: Date): String = {
+    val duration = new Date().getTime - date.getTime
+    timeUnits.find(tuple => duration / tuple._1 > 0) match {
+      case Some((unitValue, unitString)) =>
+        val value = duration / unitValue
+        s"${value} ${unitString}${if (value > 1) "s" else ""} ago"
+      case None => "just now"
+    }
+  }
+
+  /**
+   *
+   * Format java.util.Date to "x {seconds/minutes/hours/days} ago"
+   * If duration over 1 month, format to "d MMM (yyyy)"
+   *
+   */
+  def datetimeAgoRecentOnly(date: Date): String = {
+    val duration = new Date().getTime - date.getTime
+    val list = timeUnits.map(tuple => (duration / tuple._1, tuple._2)).filter(tuple => tuple._1 > 0)
+    if (list.isEmpty)
+      "just now"
+    else {
+      list.head match {
+        case (_, "month") => s"on ${new SimpleDateFormat("d MMM", Locale.ENGLISH).format(date)}"
+        case (_, "year") => s"on ${new SimpleDateFormat("d MMM yyyy", Locale.ENGLISH).format(date)}"
+        case (value, unitString) => s"${value} ${unitString}${if (value > 1) "s" else ""} ago"
+      }
+    }
+  }
+
+
   /**
    * Format java.util.Date to "yyyy-MM-dd'T'hh:mm:ss'Z'".
    */