users.gno

 1package users
 2
 3import (
 4	"chain"
 5	"chain/banker"
 6	"chain/runtime"
 7	"regexp"
 8
 9	"gno.land/p/moul/fifo"
10	susers "gno.land/r/sys/users"
11)
12
13const (
14	reValidUsername = "^[a-z]{3}[_a-z0-9]{0,14}[0-9]{3}$"
15)
16
17var (
18	registerPrice = int64(0)     // 0 GNOT
19	latestUsers   = fifo.New(10) // Save the latest 10 users for rendering purposes
20	reUsername    = regexp.MustCompile(reValidUsername)
21)
22
23// Register registers a new username for the caller.
24// A valid username must start with a minimum of 3 letters,
25// end with a minimum of 3 numbers, and be less than 20 chars long.
26// All letters must be lowercase, and the only valid special char is `_`.
27// Only calls from EOAs are supported.
28func Register(_ realm, username string) {
29	if !runtime.PreviousRealm().IsUser() {
30		panic(ErrNonUserCall)
31	}
32
33	if paused {
34		panic(ErrPaused)
35	}
36
37	if banker.OriginSend().AmountOf("ugnot") != registerPrice {
38		panic(ErrInvalidPayment)
39	}
40
41	if matched := reUsername.MatchString(username); !matched {
42		panic(ErrInvalidUsername)
43	}
44
45	registrant := runtime.PreviousRealm().Address()
46	if err := susers.RegisterUser(cross, username, registrant); err != nil {
47		panic(err)
48	}
49
50	latestUsers.Append(username)
51	chain.Emit("Registration", "address", registrant.String(), "name", username)
52}