1 files changed, 49 insertions, 0 deletions
diff --git a/src/atom/urn.rs b/src/atom/urn.rs
new file mode 100644
index 0000000..9ec73ae
--- /dev/null
+++ b/src/atom/urn.rs
@@ -0,0 +1,49 @@
+use core::fmt;
+
+use rand::{rngs::OsRng, Rng};
+
+//TODO: gen- Check URN are valid
+// https://www.rfc-editor.org/rfc/rfc2141#section-2.1
+pub struct Urn {
+	/// Namespace Identifier
+	nid: String,
+	/// Namespace Specific string. This is the unique part of the identifier
+	nss: String,
+}
+
+impl Urn {
+	/// awake specific function for generating a URN in the form of:
+	/// `urn:NID:1234-5678`
+	/// Where 1234-5678 is a randomly generated eight digit ID broken in two.
+	pub fn new_random<S: Into<String>>(nid: S) -> Self {
+		let first = random_base58(4);
+		let second = random_base58(4);
+
+		Self {
+			nid: nid.into(),
+			nss: format!("{first}-{second}"),
+		}
+	}
+}
+
+impl fmt::Display for Urn {
+	fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+		let Urn { nid, nss } = self;
+
+		write!(f, "urn:{nid}:{nss}")
+	}
+}
+
+const BASE58: &'static [u8] = b"123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz";
+const USER_ID_LENGTH: usize = 6;
+const SESSION_ID_LENGTH: usize = 12;
+
+/// Random Base58 string, `count` characters long, using OsRng which is assumed
+/// to be secure
+/// > assumed that system always provides high-quality cryptographically secure random data
+fn random_base58(count: usize) -> String {
+	let mut rng = OsRng::default();
+	std::iter::from_fn(|| Some(BASE58[rng.gen_range(0..BASE58.len())] as char))
+		.take(count)
+		.collect()
+}