From 78b3ff19251654f7e3c498f93de418476aa283f7 Mon Sep 17 00:00:00 2001
From: "hinto.janai" <hinto.janai@protonmail.com>
Date: Fri, 17 Jan 2025 14:34:16 -0500
Subject: [PATCH] fix `get_hashes`

---
 binaries/cuprated/src/rpc/handlers/bin.rs     | 18 ++++++-------
 .../cuprated/src/rpc/service/blockchain.rs    | 26 +++++++++++++++++++
 2 files changed, 34 insertions(+), 10 deletions(-)

diff --git a/binaries/cuprated/src/rpc/handlers/bin.rs b/binaries/cuprated/src/rpc/handlers/bin.rs
index 239ac8d..bb0d015 100644
--- a/binaries/cuprated/src/rpc/handlers/bin.rs
+++ b/binaries/cuprated/src/rpc/handlers/bin.rs
@@ -177,18 +177,16 @@ async fn get_hashes(
         request.block_ids[len - 1]
     };
 
-    let mut bytes = request.block_ids;
-    let hashes: Vec<[u8; 32]> = (&bytes).into();
+    let GetHashesRequest {
+        start_height,
+        block_ids,
+        ..
+    } = request;
 
-    let (current_height, _) = helper::top_height(&mut state).await?;
+    let hashes: Vec<[u8; 32]> = (&block_ids).into();
 
-    let Some((index, start_height)) =
-        blockchain::find_first_unknown(&mut state.blockchain_read, hashes).await?
-    else {
-        return Err(anyhow!("Failed"));
-    };
-
-    let m_blocks_ids = bytes.split_off(index);
+    let (m_block_ids, current_height) =
+        blockchain::next_chain_entry(&mut state.blockchain_read, hashes, start_height).await?;
 
     Ok(GetHashesResponse {
         base: helper::access_response_base(false),
diff --git a/binaries/cuprated/src/rpc/service/blockchain.rs b/binaries/cuprated/src/rpc/service/blockchain.rs
index 0912ee7..4f6402e 100644
--- a/binaries/cuprated/src/rpc/service/blockchain.rs
+++ b/binaries/cuprated/src/rpc/service/blockchain.rs
@@ -115,6 +115,32 @@ pub async fn find_block(
     Ok(option)
 }
 
+/// [`BlockchainReadRequest::NextChainEntry`].
+///
+/// Returns only the:
+/// - block IDs
+/// - current chain height
+pub async fn next_chain_entry(
+    blockchain_read: &mut BlockchainReadHandle,
+    block_hashes: Vec<[u8; 32]>,
+    len: usize,
+) -> Result<(Vec<[u8; 32]>, Option<std::num::NonZero<usize>>), Error> {
+    let BlockchainResponse::NextChainEntry {
+        block_ids,
+        chain_height,
+        ..
+    } = blockchain_read
+        .ready()
+        .await?
+        .call(BlockchainReadRequest::NextChainEntry(block_hashes, len))
+        .await?
+    else {
+        unreachable!();
+    };
+
+    Ok((block_ids, chain_height))
+}
+
 /// [`BlockchainReadRequest::FilterUnknownHashes`].
 pub async fn filter_unknown_hashes(
     blockchain_read: &mut BlockchainReadHandle,