diff --git a/stats.go b/stats.go
index 72b99be..36ca0f0 100644
--- a/stats.go
+++ b/stats.go
@@ -1,124 +1,128 @@
+// Copyright 2014-2018 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style license that can be
+// found in the LICENSE file of the Gogs project (github.com/gogs/gogs).
+
 package writefreely
 
 import (
 	"fmt"
 	"math"
 	"strings"
 	"time"
 )
 
 // Borrowed from github.com/gogs/gogs/pkg/tool
 
 // Seconds-based time units
 const (
 	Minute = 60
 	Hour   = 60 * Minute
 	Day    = 24 * Hour
 	Week   = 7 * Day
 	Month  = 30 * Day
 	Year   = 12 * Month
 )
 
 func computeTimeDiff(diff int64) (int64, string) {
 	diffStr := ""
 	switch {
 	case diff <= 0:
 		diff = 0
 		diffStr = "now"
 	case diff < 2:
 		diff = 0
 		diffStr = "1 second"
 	case diff < 1*Minute:
 		diffStr = fmt.Sprintf("%d seconds", diff)
 		diff = 0
 
 	case diff < 2*Minute:
 		diff -= 1 * Minute
 		diffStr = "1 minute"
 	case diff < 1*Hour:
 		diffStr = fmt.Sprintf("%d minutes", diff/Minute)
 		diff -= diff / Minute * Minute
 
 	case diff < 2*Hour:
 		diff -= 1 * Hour
 		diffStr = "1 hour"
 	case diff < 1*Day:
 		diffStr = fmt.Sprintf("%d hours", diff/Hour)
 		diff -= diff / Hour * Hour
 
 	case diff < 2*Day:
 		diff -= 1 * Day
 		diffStr = "1 day"
 	case diff < 1*Week:
 		diffStr = fmt.Sprintf("%d days", diff/Day)
 		diff -= diff / Day * Day
 
 	case diff < 2*Week:
 		diff -= 1 * Week
 		diffStr = "1 week"
 	case diff < 1*Month:
 		diffStr = fmt.Sprintf("%d weeks", diff/Week)
 		diff -= diff / Week * Week
 
 	case diff < 2*Month:
 		diff -= 1 * Month
 		diffStr = "1 month"
 	case diff < 1*Year:
 		diffStr = fmt.Sprintf("%d months", diff/Month)
 		diff -= diff / Month * Month
 
 	case diff < 2*Year:
 		diff -= 1 * Year
 		diffStr = "1 year"
 	default:
 		diffStr = fmt.Sprintf("%d years", diff/Year)
 		diff = 0
 	}
 	return diff, diffStr
 }
 
 // timeSincePro calculates the time interval and generate full user-friendly string.
 func timeSincePro(then time.Time) string {
 	now := time.Now()
 	diff := now.Unix() - then.Unix()
 
 	if then.After(now) {
 		return "future"
 	}
 
 	var timeStr, diffStr string
 	for {
 		if diff == 0 {
 			break
 		}
 
 		diff, diffStr = computeTimeDiff(diff)
 		timeStr += ", " + diffStr
 	}
 	return strings.TrimPrefix(timeStr, ", ")
 }
 
 func logn(n, b float64) float64 {
 	return math.Log(n) / math.Log(b)
 }
 
 func humanateBytes(s uint64, base float64, sizes []string) string {
 	if s < 10 {
 		return fmt.Sprintf("%d B", s)
 	}
 	e := math.Floor(logn(float64(s), base))
 	suffix := sizes[int(e)]
 	val := float64(s) / math.Pow(base, math.Floor(e))
 	f := "%.0f"
 	if val < 10 {
 		f = "%.1f"
 	}
 
 	return fmt.Sprintf(f+" %s", val, suffix)
 }
 
 // fileSize calculates the file size and generate user-friendly string.
 func fileSize(s int64) string {
 	sizes := []string{"B", "KB", "MB", "GB", "TB", "PB", "EB"}
 	return humanateBytes(uint64(s), 1024, sizes)
 }