improvement(NIP-19): identify and parse NIP-19 addresses

src/utils.rs

@@ -1,4 +1,5 @@
 //! Common utility functions
+use bech32::FromBase32;
 use std::time::SystemTime;
 
 /// Seconds since 1970.
@@ -14,6 +15,17 @@ use std::time::SystemTime;
     s.chars().all(|x| char::is_ascii_hexdigit(&x))
 }
 
+/// Check if string is a nip19 string
+pub fn is_nip19(s: &str) -> bool {
+    s.starts_with("npub") || s.starts_with("note")
+}
+
+pub fn nip19_to_hex(s: &str) -> Result<String, bech32::Error> {
+    let (_hrp, data, _checksum) = bech32::decode(s)?;
+    let data = Vec::<u8>::from_base32(&data)?;
+    Ok(hex::encode(data))
+}
+
 /// Check if a string contains only lower-case hex chars.
 #[must_use] pub fn is_lower_hex(s: &str) -> bool {
     s.chars().all(|x| {
@@ -30,4 +42,21 @@ mod tests {
         let hexstr = "abcd0123";
         assert_eq!(is_lower_hex(hexstr), true);
     }
+
+    #[test]
+    fn nip19() {
+        let hexkey = "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d";
+        let nip19key = "npub180cvv07tjdrrgpa0j7j7tmnyl2yr6yr7l8j4s3evf6u64th6gkwsyjh6w6";
+        assert_eq!(is_nip19(hexkey), false);
+        assert_eq!(is_nip19(nip19key), true);
+    }
+
+    #[test]
+    fn nip19_hex() {
+        let nip19key = "npub180cvv07tjdrrgpa0j7j7tmnyl2yr6yr7l8j4s3evf6u64th6gkwsyjh6w6";
+        let expected = "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d";
+        let got = nip19_to_hex(nip19key).unwrap();
+
+        assert_eq!(expected, got);
+    }
 }