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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
}
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