From 19982889f7f4c073d182a6076633c5e2c892c73a Mon Sep 17 00:00:00 2001
From: Daniel Wang <99078276+dantaik@users.noreply.github.com>
Date: Thu, 1 Aug 2024 14:00:02 +0800
Subject: [PATCH] feat(protocol): return verification timestamp in
 getLastVerifiedBlock (#17868)

Co-authored-by: D <51912515+adaki2004@users.noreply.github.com>
---
 packages/protocol/contracts/L1/TaikoL1.sol       | 10 ++++++----
 packages/protocol/contracts/L1/libs/LibUtils.sol |  3 ++-
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/packages/protocol/contracts/L1/TaikoL1.sol b/packages/protocol/contracts/L1/TaikoL1.sol
index 1f4a39f1bb..43ad057fbe 100644
--- a/packages/protocol/contracts/L1/TaikoL1.sol
+++ b/packages/protocol/contracts/L1/TaikoL1.sol
@@ -228,26 +228,28 @@ contract TaikoL1 is EssentialContract, ITaikoL1, TaikoEvents {
     /// @return blockId_ The last verified block's ID.
     /// @return blockHash_ The last verified block's blockHash.
     /// @return stateRoot_ The last verified block's stateRoot.
+    /// @return verifiedAt_ The timestamp this block is verified at.
     function getLastVerifiedBlock()
         external
         view
-        returns (uint64 blockId_, bytes32 blockHash_, bytes32 stateRoot_)
+        returns (uint64 blockId_, bytes32 blockHash_, bytes32 stateRoot_, uint64 verifiedAt_)
     {
         blockId_ = state.slotB.lastVerifiedBlockId;
-        (blockHash_, stateRoot_) = LibUtils.getBlockInfo(state, getConfig(), blockId_);
+        (blockHash_, stateRoot_, verifiedAt_) = LibUtils.getBlockInfo(state, getConfig(), blockId_);
     }
 
     /// @notice Returns information about the last synchronized block.
     /// @return blockId_ The last verified block's ID.
     /// @return blockHash_ The last verified block's blockHash.
     /// @return stateRoot_ The last verified block's stateRoot.
+    /// @return verifiedAt_ The timestamp this block is verified at.
     function getLastSyncedBlock()
         external
         view
-        returns (uint64 blockId_, bytes32 blockHash_, bytes32 stateRoot_)
+        returns (uint64 blockId_, bytes32 blockHash_, bytes32 stateRoot_, uint64 verifiedAt_)
     {
         blockId_ = state.slotA.lastSyncedBlockId;
-        (blockHash_, stateRoot_) = LibUtils.getBlockInfo(state, getConfig(), blockId_);
+        (blockHash_, stateRoot_, verifiedAt_) = LibUtils.getBlockInfo(state, getConfig(), blockId_);
     }
 
     /// @notice Gets the state variables of the TaikoL1 contract.
diff --git a/packages/protocol/contracts/L1/libs/LibUtils.sol b/packages/protocol/contracts/L1/libs/LibUtils.sol
index 0eadc38434..3f7fa3c36e 100644
--- a/packages/protocol/contracts/L1/libs/LibUtils.sol
+++ b/packages/protocol/contracts/L1/libs/LibUtils.sol
@@ -127,7 +127,7 @@ library LibUtils {
     )
         internal
         view
-        returns (bytes32 blockHash_, bytes32 stateRoot_)
+        returns (bytes32 blockHash_, bytes32 stateRoot_, uint64 verifiedAt_)
     {
         (TaikoData.Block storage blk, uint64 slot) = getBlock(_state, _config, _blockId);
 
@@ -137,6 +137,7 @@ library LibUtils {
 
             blockHash_ = transition.blockHash;
             stateRoot_ = transition.stateRoot;
+            verifiedAt_ = transition.timestamp;
         }
     }