kot.pink
1package userutil
2
3import (
4 "regexp"
5 "strings"
6)
7
8var (
9 handleRegex = regexp.MustCompile(`^([a-zA-Z0-9]([a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?\.)+[a-zA-Z]([a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?$`)
10 didRegex = regexp.MustCompile(`^did:[a-z]+:[a-zA-Z0-9._:%-]*[a-zA-Z0-9._-]$`)
11)
12
13func IsHandleNoAt(s string) bool {
14 // ref: https://atproto.com/specs/handle
15 return handleRegex.MatchString(s)
16}
17
18func UnflattenDid(s string) string {
19 if !IsFlattenedDid(s) {
20 return s
21 }
22
23 return strings.Replace(s, "-", ":", 2)
24}
25
26// IsFlattenedDid checks if the given string is a flattened DID.
27func IsFlattenedDid(s string) bool {
28 // Check if the string starts with "did-"
29 if !strings.HasPrefix(s, "did-") {
30 return false
31 }
32
33 // Reconstruct as a standard DID format using Replace
34 // Example: "did-plc-xyz-abc" becomes "did:plc:xyz-abc"
35 reconstructed := strings.Replace(s, "-", ":", 2)
36
37 return didRegex.MatchString(reconstructed)
38}
39
40// FlattenDid converts a DID to a flattened format.
41// A flattened DID is a DID with the :s swapped to -s to satisfy certain
42// application requirements, such as Go module naming conventions.
43func FlattenDid(s string) string {
44 if IsDid(s) {
45 return strings.Replace(s, ":", "-", 2)
46 }
47 return s
48}
49
50// IsDid checks if the given string is a standard DID.
51func IsDid(s string) bool {
52 return didRegex.MatchString(s)
53}
54
55var subdomainRegex = regexp.MustCompile(`^[a-z0-9]([a-z0-9-]{2,61}[a-z0-9])?$`)
56
57func IsValidSubdomain(name string) bool {
58 return len(name) >= 4 && len(name) <= 63 && subdomainRegex.MatchString(name)
59}