1 files changed, 26 insertions, 1 deletions

diff --git a/src/utils.pug b/src/utils.pug
index f3f61bb..81cf3f7 100644
--- a/src/utils.pug
+++ b/src/utils.pug
@@ -1,3 +1,28 @@
 - var fmtnum = (n)=>n>=1000?(n/1000).toFixed(1)+'k':n;
 - var fmttxt = (n,t)=>`${t}${n==1?'':'s'}`
-
+- var stripPrefix = (s, p) => s.startsWith(p) ? s.slice(p.length) : s;
+-
+  function timeDifference(current, previous) {
+    if (!current || !previous) {
+        return '';
+    }
+    var msPerMinute = 60 * 1000;
+    var msPerHour = msPerMinute * 60;
+    var msPerDay = msPerHour * 24;
+    var msPerMonth = msPerDay * 30;
+    var msPerYear = msPerDay * 365;
+    var elapsed = current - previous;
+    if (elapsed < msPerMinute) {
+         return Math.round(elapsed/1000) + 's';
+    } else if (elapsed < msPerHour) {
+         return Math.round(elapsed/msPerMinute) + 'min';
+    } else if (elapsed < msPerDay ) {
+         return Math.round(elapsed/msPerHour ) + 'h';
+    } else if (elapsed < msPerMonth) {
+        return Math.round(elapsed/msPerDay) + 'd';
+    } else if (elapsed < msPerYear) {
+        return Math.round(elapsed/msPerMonth) + 'mo';
+    } else {
+        return Math.round(elapsed/msPerYear ) + 'y';
+    }
+  }