make mail a service

internal/constant/cast.go

@@ -0,0 +1,18 @@
+package constant
+
+const (
+	BinaryMessageTypeState      = 0
+	BinaryMessageTypeChat       = 1
+	BinaryMessageTypeQuest      = 2
+	BinaryMessageTypeData       = 3
+	BinaryMessageTypeMailNotify = 4
+	BinaryMessageTypeEmote      = 6
+)
+
+// MSG_SYS_CAST[ED]_BINARY broadcast types enum
+const (
+	BroadcastTypeTargeted = 0x01
+	BroadcastTypeStage    = 0x03
+	BroadcastTypeServer   = 0x06
+	BroadcastTypeWorld    = 0x0a
+)