1 files changed, 70 insertions, 0 deletions
diff --git a/underlays/javascript/relativedate.js b/underlays/javascript/relativedate.js
new file mode 100644
index 000000000..c5e62b3cc
--- /dev/null
+++ b/underlays/javascript/relativedate.js
@@ -0,0 +1,70 @@
+// Causes html elements in the 'date' and 'pagedate' classes to be displayed
+// as relative dates. The date is parsed from the title attribute, or from
+// the element content.
+
+var dateElements;
+
+hook("onload", getDates);
+
+function getDates() {
+	dateElements = getElementsByClass('date');
+	for (var i = 0; i < dateElements.length; i++) {
+		var elt = dateElements[i];
+		var title = elt.attributes.title;
+		var d = new Date(title ? title.value : elt.innerHTML);
+		if (! isNaN(d)) {
+			dateElements[i].date=d;
+			elt.title=elt.innerHTML;
+		}
+	}
+
+	showDates();
+}
+
+function showDates() {
+	for (var i = 0; i < dateElements.length; i++) {
+		var elt = dateElements[i];
+		var d = elt.date;
+		if (! isNaN(d)) {
+			elt.innerHTML=relativeDate(d);
+		}
+	}
+	setTimeout(showDates,30000); // keep updating every 30s
+}
+
+var timeUnits = new Array;
+timeUnits['minute'] = 60;
+timeUnits['hour'] = timeUnits['minute'] * 60;
+timeUnits['day'] = timeUnits['hour'] * 24;
+timeUnits['month'] = timeUnits['day'] * 30;
+timeUnits['year'] = timeUnits['day'] * 364;
+var timeUnitOrder = ['year', 'month', 'day', 'hour', 'minute'];
+
+function relativeDate(date) {
+	var now = new Date();
+	var offset = date.getTime() - now.getTime();
+	var seconds = Math.round(Math.abs(offset) / 1000);
+
+	var ret = "";
+	var shown = 0;
+	for (i = 0; i < timeUnitOrder.length; i++) {
+		var unit = timeUnitOrder[i];
+		if (seconds >= timeUnits[unit]) {
+			var num = Math.floor(seconds / timeUnits[unit]);
+			seconds -= num * timeUnits[unit];
+			if (ret)
+				ret += "and ";
+			ret += num + " " + unit + (num > 1 ? "s" : "") + " ";
+
+			if (++shown == 2)
+				break;
+		}
+		else if (shown)
+			break;
+	}
+
+	if (! ret)
+		ret = "less than a minute "
+
+	return ret + (offset < 0 ? "ago" : "from now");
+}