feat(xp): xp and level gain

xp/events.go

@@ -0,0 +1,40 @@
+package xp
+
+import (
+	"github.com/anhgelus/gokord/utils"
+	"github.com/bwmarrin/discordgo"
+)
+
+func OnMessage(s *discordgo.Session, m *discordgo.MessageCreate) {
+	c := Copaing{DiscordID: m.Author.ID, GuildID: m.GuildID}
+	c.Load()
+	// add xp
+	pastLevel := Level(c.XP)
+	trimmed := utils.TrimMessage(m.Content)
+	c.XP += XPMessage(uint(len(trimmed)), calcDiversity(trimmed))
+	c.Save()
+	newLevel := Level(c.XP)
+	// handle new level
+	if pastLevel < newLevel {
+		if err := s.MessageReactionAdd(m.ChannelID, m.Message.ID, "⬆"); err != nil {
+			utils.SendAlert("xp/events.go - reaction add new level", "cannot add the reaction: "+err.Error())
+		}
+		onNewLevel(s, newLevel)
+	}
+}
+
+func calcDiversity(msg string) uint {
+	var chars []rune
+	for _, c := range []rune(msg) {
+		toAdd := true
+		for _, ch := range chars {
+			if ch == c {
+				toAdd = false
+			}
+		}
+		if toAdd {
+			chars = append(chars, c)
+		}
+	}
+	return uint(len(chars))
+}