NoteBytes moved to zcash_note_encryption (copy of #8)

src/lib.rs

@@ -39,6 +39,7 @@ use subtle::{Choice, ConstantTimeEq};
 #[cfg(feature = "alloc")]
 #[cfg_attr(docsrs, doc(cfg(feature = "alloc")))]
 pub mod batch;
+pub mod note_bytes;
 
 /// The size of the memo.
 pub const MEMO_SIZE: usize = 512;

src/note_bytes.rs

@@ -0,0 +1,66 @@
+/// Represents a fixed-size array of bytes for note components.
+#[derive(Clone, Copy, Debug)]
+pub struct NoteBytesData<const N: usize>(pub [u8; N]);
+
+impl<const N: usize> AsRef<[u8]> for NoteBytesData<N> {
+    fn as_ref(&self) -> &[u8] {
+        &self.0
+    }
+}
+
+impl<const N: usize> AsMut<[u8]> for NoteBytesData<N> {
+    fn as_mut(&mut self) -> &mut [u8] {
+        &mut self.0
+    }
+}
+
+impl<const N: usize> From<&[u8]> for NoteBytesData<N> {
+    fn from(s: &[u8]) -> Self {
+        Self(s.try_into().unwrap())
+    }
+}
+
+impl<const N: usize> From<(&[u8], &[u8])> for NoteBytesData<N> {
+    fn from(s: (&[u8], &[u8])) -> Self {
+        let mut result: [u8; N] = [0; N];
+        result[..s.0.len()].copy_from_slice(s.0);
+        result[s.0.len()..].copy_from_slice(s.1);
+        NoteBytesData::from(result.as_ref())
+    }
+}
+
+/// Defines the ability to concatenate two byte slices.
+pub trait NoteByteConcat: for<'a> From<(&'a [u8], &'a [u8])> {}
+
+impl<const N: usize> NoteByteConcat for NoteBytesData<N> {}
+
+/// Defines the behavior for types that can provide read-only access to their internal byte array.
+pub trait NoteByteReader: AsRef<[u8]> + for<'a> From<&'a [u8]> + Clone + Copy {}
+
+impl<const N: usize> NoteByteReader for NoteBytesData<N> {}
+
+/// Defines the behavior for types that support both read and write access to their internal byte array.
+pub trait NoteByteWriter: NoteByteReader + AsMut<[u8]> {}
+
+impl<const N: usize> NoteByteWriter for NoteBytesData<N> {}
+
+/// Provides a unified interface for handling fixed-size byte arrays used in Orchard note encryption.
+pub trait NoteBytes:
+    AsRef<[u8]>
+    + AsMut<[u8]>
+    + for<'a> From<&'a [u8]>
+    + for<'a> From<(&'a [u8], &'a [u8])>
+    + Clone
+    + Copy
+    + Send
+{
+    /// Constructs a new NoteBytesData from an empty slice of bytes.
+    fn new() -> Self;
+}
+
+impl<const N: usize> NoteBytes for NoteBytesData<N> {
+    /// Constructs a new NoteBytesData from an empty slice of bytes.
+    fn new() -> Self {
+        Self([0u8; N])
+    }
+}