Add human-readable idle time in whois info

client/views/actions/whois.tpl

@@ -33,3 +33,9 @@
 	is away <i>({{whois.away}})</i>
 </div>
 {{/if}}
+{{#if whois.idle}}
+<div>
+	<span role="button" class="user {{colorClass whois.nick}}" data-name="{{whois.nick}}">{{whois.nick}}</span>
+	has been idle since {{localetime whois.idleTime}}.
+</div>
+{{/if}}

src/plugins/irc-events/whois.js

@@ -27,6 +27,9 @@ module.exports = function(irc, network) {
 				text: "No such nick: " + data.nick
 			});
 		} else {
+			// Absolute datetime in milliseconds since nick is idle
+			data.idleTime = Date.now() - data.idle * 1000;
+
 			msg = new Msg({
 				type: Msg.Type.WHOIS,
 				whois: data