That's a good stopping point

socketserver/cmd/statsweb/html.go

@@ -0,0 +1,59 @@
+package main
+
+import (
+	"html/template"
+	"net/http"
+	"time"
+	"bitbucket.org/stendec/frankerfacez/socketserver/server"
+)
+
+type CalendarData struct {
+	Weeks []CalWeekData
+}
+type CalWeekData struct {
+	Days []CalDayData
+}
+type CalDayData struct {
+	NoData bool
+	Date int
+	UniqUsers int
+}
+
+type CalendarMonthInfo struct {
+	Year int
+	Month time.Month
+	// Ranges from -5 to +1.
+	// A value of +1 means the 1st of the month is a Sunday.
+	// A value of 0 means the 1st of the month is a Monday.
+	// A value of -5 means the 1st of the month is a Saturday.
+	FirstSundayOffset int
+	// True if the calendar for this month needs six sundays.
+	NeedSixSundays bool
+}
+
+func GetMonthInfo(at time.Time) CalendarMonthInfo {
+	year, month, _ := at.Date()
+	// 1 (start of month) - weekday of start of month = day offset of start of week at start of month
+	monthWeekStartDay := 1 - time.Date(year, month, 1, 0, 0, 0, 0, server.CounterLocation).Weekday()
+	// first day on calendar + 6 weeks < end of month?
+	sixthSundayDay := monthWeekStartDay + 5*7
+	sixthSundayDate := time.Date(year, month, sixthSundayDay, 0, 0, 0, 0, server.CounterLocation)
+	var needSixSundays bool = false
+	if sixthSundayDate.Month() == month {
+		needSixSundays = true
+	}
+
+	return CalendarMonthInfo{
+		Year: year,
+		Month: month,
+		FirstSundayOffset: monthWeekStartDay,
+		NeedSixSundays: needSixSundays,
+	}
+}
+
+func renderCalendar(w http.ResponseWriter, at time.Time) {
+	layout, err := template.ParseFiles("./webroot/layout.template.html", "./webroot/cal_entry.hbs", "./webroot/calendar.hbs")
+	data := CalendarData{}
+	data.Weeks = make([]CalWeekData, 6)
+
+}