From 22c599abc18895f73e96095f35b71cf3357d41b4 Mon Sep 17 00:00:00 2001 From: Jeff Halter <868228+jhalter@users.noreply.github.com> Date: Wed, 28 Jul 2021 18:21:52 -0700 Subject: Move code to hotline dir --- hotline/user.go | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) create mode 100644 hotline/user.go (limited to 'hotline/user.go') diff --git a/hotline/user.go b/hotline/user.go new file mode 100644 index 0000000..f80fd72 --- /dev/null +++ b/hotline/user.go @@ -0,0 +1,69 @@ +package hotline + +import ( + "encoding/binary" +) + +// User flags are stored as a 2 byte bitmap with the following values: +const ( + userFlagAway = 0 // User is away + userFlagAdmin = 1 // User is admin + userFlagRefusePM = 2 // User refuses private messages + userFLagRefusePChat = 3 // User refuses private chat +) + +type User struct { + ID []byte // Size 2 + Icon []byte // Size 2 + Flags []byte // Size 2 + Name string // Variable length user name +} + +func (u User) Payload() []byte { + nameLen := make([]byte, 2) + binary.BigEndian.PutUint16(nameLen, uint16(len(u.Name))) + + if len(u.Icon) == 4 { + u.Icon = u.Icon[2:] + } + + if len(u.Flags) == 4 { + u.Flags = u.Flags[2:] + } + + out := append(u.ID[:2], u.Icon[:2]...) + out = append(out, u.Flags[:2]...) + out = append(out, nameLen...) + out = append(out, u.Name...) + + return out +} + +func ReadUser(b []byte) (*User, error) { + u := &User{ + ID: b[0:2], + Icon: b[2:4], + Flags: b[4:6], + Name: string(b[8:]), + } + return u, nil +} + +// DecodeUserString decodes an obfuscated user string from a client +// e.g. 98 8a 9a 8c 8b => "guest" +func DecodeUserString(encodedString []byte) (decodedString string) { + for _, char := range encodedString { + decodedString += string(rune(255 - uint(char))) + } + return decodedString +} + +// Take a []byte of uncoded ascii as input and encode it +// TODO: change the method signature to take a string and return []byte +func NegatedUserString(encodedString []byte) string { + var decodedString string + for _, char := range encodedString { + decodedString += string(255 - uint8(char))[1:] + } + return decodedString +} -- cgit