From 1605f43d9f73405760b847f2e8164d202c36c445 Mon Sep 17 00:00:00 2001
From: Luther Wen Xu <lutherchanpublic+git@gmail.com>
Date: Sun, 7 Jun 2020 19:52:29 +0800
Subject: [PATCH] refactor: Move base64 generation to util

---
 commands/migrate.go | 18 ++----------------
 util/rand.go        | 10 ++++++++++
 2 files changed, 12 insertions(+), 16 deletions(-)

diff --git a/commands/migrate.go b/commands/migrate.go
index ee0ee5a..904da1a 100644
--- a/commands/migrate.go
+++ b/commands/migrate.go
@@ -2,8 +2,6 @@ package commands
 
 import (
 	"fmt"
-	"math/rand"
-	"time"
 
 	"github.com/bwmarrin/discordgo"
 
@@ -29,25 +27,13 @@ func handleRecalculateLevel(dg *discordgo.Session, m *discordgo.MessageCreate, a
 		)
 	}
 	util.SendSuccessEmbed(dg, m.ChannelID, "Level is being recalculated.")
-	rand.Seed(time.Now().UnixNano())
-	calculationCode = randomBase64(20)
+	calculationCode = util.RandomBase64(20)
 	level.RecalculateEverything(dg, m.GuildID)
 	util.SendSuccessEmbed(dg, m.ChannelID, "Level recalculated successfully.")
 }
 
-const letterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789+="
-
 var calculationCode string
 
 func init() {
-	rand.Seed(time.Now().UnixNano())
-	calculationCode = randomBase64(20)
-}
-
-func randomBase64(n int) string {
-	b := make([]byte, n)
-	for i := range b {
-		b[i] = letterBytes[rand.Int63()%int64(len(letterBytes))]
-	}
-	return string(b)
+	calculationCode = util.RandomBase64(20)
 }
diff --git a/util/rand.go b/util/rand.go
index 4df0b59..cb12d05 100644
--- a/util/rand.go
+++ b/util/rand.go
@@ -28,3 +28,13 @@ func (s src) Seed(seed int64) {
 }
 
 var Rand = mrand.New(src{})
+
+const letterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789+="
+
+func RandomBase64(n int) string {
+	b := make([]byte, n)
+	for i := range b {
+		b[i] = letterBytes[Rand.Intn(64)]
+	}
+	return string(b)
+}