town/codes/codes.go

48 lines
928 B
Go

package codes
import (
"crypto/rand"
"encoding/base64"
"math/big"
"strings"
)
const codeLen = 32
func NewCode(email string) string {
charset := "abcdefghijklmnopqrztuvwxyz"
charset += strings.ToUpper(charset)
charset += "0123456789"
charset += "`~!@#$%^&*()-=_+[]{}|;:,./<>?"
code := []byte{}
max := big.NewInt(int64(len(charset)))
for len(code) < codeLen {
ix, err := rand.Int(rand.Reader, max)
if err != nil {
// TODO this is bad but I'm just kind of hoping it doesn't happen...often
panic(err)
}
code = append(code, charset[ix.Int64()])
}
code = append(code, ' ')
eb := []byte(email)
for x := 0; x < len(eb); x++ {
code = append(code, eb[x])
}
return base64.StdEncoding.EncodeToString(code)
}
func Decode(code string) ([]string, error) {
decoded, err := base64.StdEncoding.DecodeString(code)
if err != nil {
return nil, err
}
return strings.Split(string(decoded), " "), nil
}