From dc769f26ca16527685916e6814b10f73c9b8b00c Mon Sep 17 00:00:00 2001
From: benesjan <janbenes1234@gmail.com>
Date: Mon, 23 Dec 2024 21:08:42 +0000
Subject: [PATCH] WIP

---
 cspell.json                                   |  1 +
 .../aztec-nr/aztec/src/macros/notes/mod.nr    | 31 ++++++++++---------
 .../aztec-nr/aztec/src/note/note_type_id.nr   |  1 -
 .../circuit-types/src/interfaces/pxe.ts       |  2 +-
 4 files changed, 18 insertions(+), 17 deletions(-)
 delete mode 100644 noir-projects/aztec-nr/aztec/src/note/note_type_id.nr

diff --git a/cspell.json b/cspell.json
index 3ed9bc44cf4..0002201c734 100644
--- a/cspell.json
+++ b/cspell.json
@@ -175,6 +175,7 @@
     "noirc",
     "noirup",
     "nullifer",
+    "Nullifiable",
     "offchain",
     "onchain",
     "opentelemetry",
diff --git a/noir-projects/aztec-nr/aztec/src/macros/notes/mod.nr b/noir-projects/aztec-nr/aztec/src/macros/notes/mod.nr
index 5d8aa114b09..584ee4ff8b4 100644
--- a/noir-projects/aztec-nr/aztec/src/macros/notes/mod.nr
+++ b/noir-projects/aztec-nr/aztec/src/macros/notes/mod.nr
@@ -19,19 +19,19 @@ comptime global NOTE_HEADER_TYPE: Type = type_of(NoteHeader::empty());
 pub comptime mut global NOTES: UHashMap<Type, (StructDefinition, u32, Field, [(Quoted, u32, bool)]), BuildHasherDefault<Poseidon2Hasher>> =
     UHashMap::default();
 
-/// Computes a note type id by hashing a note name (e.g. `TokenNote`), getting the first 4 bytes of the hash
-/// and returning it as a `Field`.
-comptime fn compute_note_type_id(name: Quoted) -> Field {
-    let (name_as_str_quote, _) = name.as_str_quote();
+pub comptime mut global NOTE_TYPE_ID_COUNTER: u32 = 0;
+
+/// The note type id is set by enumerating the note types.
+comptime fn get_next_note_type_id() -> Field {
+    // We assert that the note type id fits within 7 bits
+    assert(
+        NOTE_TYPE_ID_COUNTER < 128 as u32,
+        "A contract can contain at most 128 different note types",
+    );
 
-    unquote!(
-        quote {
-            let bytes = $name_as_str_quote.as_bytes();
-            let hash = protocol_types::hash::poseidon2_hash_bytes(bytes);
-            let hash_bytes = hash.to_be_bytes::<4>();
-            protocol_types::utils::field::field_from_bytes(hash_bytes, true)
-        },
-    )
+    let note_type_id = NOTE_TYPE_ID_COUNTER as Field;
+    NOTE_TYPE_ID_COUNTER += 1;
+    note_type_id
 }
 
 /// Generates default `NoteInterface` implementation for a given note struct `s` and returns it as quote along with
@@ -123,6 +123,7 @@ comptime fn generate_note_interface(
                 let mut buffer: [u8; $content_len * 32 + 64] = [0; $content_len * 32 + 64];
 
                 let storage_slot_bytes: [u8; 32] = storage_slot.to_be_bytes();
+                // TODO(#10952): The following can be reduced to 7 bits
                 let note_type_id_bytes: [u8; 32] = $name::get_note_type_id().to_be_bytes();
 
                 for i in 0..32 {
@@ -871,7 +872,7 @@ pub comptime fn partial_note(s: StructDefinition, nullable_fields: [Quoted]) ->
     inject_note_header(s);
 
     let note_properties = generate_note_properties(s);
-    let note_type_id = compute_note_type_id(s.name());
+    let note_type_id = get_next_note_type_id();
     let (setup_payload_impl, setup_payload_name) =
         generate_setup_payload(s, indexed_fixed_fields, indexed_nullable_fields);
     let (finalization_payload_impl, finalization_payload_name) =
@@ -914,7 +915,7 @@ pub comptime fn note(s: StructDefinition) -> Quoted {
     inject_note_header(s);
 
     let note_properties = generate_note_properties(s);
-    let note_type_id = compute_note_type_id(s.name());
+    let note_type_id = get_next_note_type_id();
     let (note_interface_impl, note_serialized_len) = generate_note_interface(
         s,
         note_type_id,
@@ -944,7 +945,7 @@ pub comptime fn note_custom_interface(s: StructDefinition) -> Quoted {
     inject_note_header(s);
 
     let note_properties = generate_note_properties(s);
-    let note_type_id = compute_note_type_id(s.name());
+    let note_type_id = get_next_note_type_id();
     let serialized_len_type = fresh_type_variable();
     let note_interface_impl = s.as_type().get_trait_impl(
         quote { crate::note::note_interface::NoteInterface<$serialized_len_type> }
diff --git a/noir-projects/aztec-nr/aztec/src/note/note_type_id.nr b/noir-projects/aztec-nr/aztec/src/note/note_type_id.nr
deleted file mode 100644
index 8b137891791..00000000000
--- a/noir-projects/aztec-nr/aztec/src/note/note_type_id.nr
+++ /dev/null
@@ -1 +0,0 @@
-
diff --git a/yarn-project/circuit-types/src/interfaces/pxe.ts b/yarn-project/circuit-types/src/interfaces/pxe.ts
index d70216ef15c..13fd3dbe8b1 100644
--- a/yarn-project/circuit-types/src/interfaces/pxe.ts
+++ b/yarn-project/circuit-types/src/interfaces/pxe.ts
@@ -388,7 +388,7 @@ export interface PXE {
   isContractInitialized(address: AztecAddress): Promise<boolean>;
 
   /**
-   * Returns the enctypred events given search parameters.
+   * Returns the encrypted events given search parameters.
    * @param eventMetadata - Metadata of the event. This should be the class generated from the contract. e.g. Contract.events.Event
    * @param from - The block number to search from.
    * @param limit - The amount of blocks to search.