1 files changed, 76 insertions, 0 deletions
diff --git a/azalea-buf/src/serializable_uuid.rs b/azalea-buf/src/serializable_uuid.rs
new file mode 100644
index 00000000..10921aa6
--- /dev/null
+++ b/azalea-buf/src/serializable_uuid.rs
@@ -0,0 +1,76 @@
+use crate::{McBufReadable, McBufWritable, Readable};
+use std::io::{Read, Write};
+use uuid::Uuid;
+
+pub trait SerializableUuid {
+    fn to_int_array(&self) -> [u32; 4];
+    fn from_int_array(array: [u32; 4]) -> Self;
+}
+
+fn least_most_to_int_array(most: u64, least: u64) -> [u32; 4] {
+    [
+        (most >> 32) as u32,
+        most as u32,
+        (least >> 32) as u32,
+        least as u32,
+    ]
+}
+
+impl SerializableUuid for Uuid {
+    fn to_int_array(&self) -> [u32; 4] {
+        let most_significant_bits = (self.as_u128() >> 64) as u64;
+        let least_significant_bits = (self.as_u128() & 0xffffffffffffffff) as u64;
+
+        least_most_to_int_array(most_significant_bits, least_significant_bits)
+    }
+
+    fn from_int_array(array: [u32; 4]) -> Self {
+        let most = ((array[0] as u64) << 32) | ((array[1] as u64) & 0xFFFFFFFF);
+        let least = ((array[2] as u64) << 32) | ((array[3] as u64) & 0xFFFFFFFF);
+
+        Uuid::from_u128(((most as u128) << 64) | least as u128)
+    }
+}
+
+impl McBufReadable for Uuid {
+    fn read_into(buf: &mut impl Read) -> Result<Self, String> {
+        Ok(Uuid::from_int_array([
+            Readable::read_int(buf)? as u32,
+            Readable::read_int(buf)? as u32,
+            Readable::read_int(buf)? as u32,
+            Readable::read_int(buf)? as u32,
+        ]))
+    }
+}
+
+impl McBufWritable for Uuid {
+    fn write_into(&self, buf: &mut impl Write) -> Result<(), std::io::Error> {
+        let [a, b, c, d] = self.to_int_array();
+        a.write_into(buf)?;
+        b.write_into(buf)?;
+        c.write_into(buf)?;
+        d.write_into(buf)?;
+        Ok(())
+    }
+}
+
+// TODO: add a test for Uuid in McBuf
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn to_int_array() {
+        let u = Uuid::parse_str("6536bfed-8695-48fd-83a1-ecd24cf2a0fd").unwrap();
+        assert_eq!(
+            u.to_int_array(),
+            [0x6536bfed, 0x869548fd, 0x83a1ecd2, 0x4cf2a0fd]
+        );
+    }
+
+    #[test]
+    fn from_int_array() {
+        let u = Uuid::from_int_array([0x6536bfed, 0x869548fd, 0x83a1ecd2, 0x4cf2a0fd]);
+        assert_eq!(u.to_string(), "6536bfed-8695-48fd-83a1-ecd24cf2a0fd");
+    }
+}