From 3505a2a2f3fda2af3892f861158abe61db57160d Mon Sep 17 00:00:00 2001
From: David <david@taiko.xyz>
Date: Wed, 19 Feb 2025 15:35:26 +0800
Subject: [PATCH] feat(taiko-client): include `ParentMetaHash` for proposing
 Ontake blocks for better revert protection

---
 .../proposer/transaction_builder/blob.go      | 21 +++++++++++++++---
 .../proposer/transaction_builder/calldata.go  | 22 ++++++++++++++++---
 2 files changed, 37 insertions(+), 6 deletions(-)

diff --git a/packages/taiko-client/proposer/transaction_builder/blob.go b/packages/taiko-client/proposer/transaction_builder/blob.go
index 2522f460bfd..8fcf29d2101 100644
--- a/packages/taiko-client/proposer/transaction_builder/blob.go
+++ b/packages/taiko-client/proposer/transaction_builder/blob.go
@@ -91,10 +91,9 @@ func (b *BlobTransactionBuilder) BuildOntake(
 		if err := blob.FromData(txListBytesArray[i]); err != nil {
 			return nil, err
 		}
-
 		blobs = append(blobs, blob)
 
-		encodedParams, err := encoding.EncodeBlockParamsOntake(&encoding.BlockParamsV2{
+		params := &encoding.BlockParamsV2{
 			Coinbase:         b.l2SuggestedFeeRecipient,
 			ParentMetaHash:   [32]byte{},
 			AnchorBlockId:    0,
@@ -102,7 +101,23 @@ func (b *BlobTransactionBuilder) BuildOntake(
 			BlobTxListOffset: 0,
 			BlobTxListLength: uint32(len(txListBytesArray[i])),
 			BlobIndex:        uint8(i),
-		})
+		}
+
+		if i == 0 && b.revertProtectionEnabled {
+			_, slotB, err := b.rpc.GetProtocolStateVariablesOntake(nil)
+			if err != nil {
+				return nil, err
+			}
+
+			blockInfo, err := b.rpc.GetL2BlockInfoV2(ctx, new(big.Int).SetUint64(slotB.NumBlocks-1))
+			if err != nil {
+				return nil, err
+			}
+
+			params.ParentMetaHash = blockInfo.MetaHash
+		}
+
+		encodedParams, err := encoding.EncodeBlockParamsOntake(params)
 		if err != nil {
 			return nil, err
 		}
diff --git a/packages/taiko-client/proposer/transaction_builder/calldata.go b/packages/taiko-client/proposer/transaction_builder/calldata.go
index abd75342ed7..6d4f80935ac 100644
--- a/packages/taiko-client/proposer/transaction_builder/calldata.go
+++ b/packages/taiko-client/proposer/transaction_builder/calldata.go
@@ -80,13 +80,29 @@ func (b *CalldataTransactionBuilder) BuildOntake(
 		encodedParamsArray [][]byte
 	)
 
-	for range txListBytesArray {
-		encodedParams, err := encoding.EncodeBlockParamsOntake(&encoding.BlockParamsV2{
+	for i := range txListBytesArray {
+		params := &encoding.BlockParamsV2{
 			Coinbase:       b.l2SuggestedFeeRecipient,
 			ParentMetaHash: [32]byte{},
 			AnchorBlockId:  0,
 			Timestamp:      0,
-		})
+		}
+
+		if i == 0 && b.revertProtectionEnabled {
+			_, slotB, err := b.rpc.GetProtocolStateVariablesOntake(nil)
+			if err != nil {
+				return nil, err
+			}
+
+			blockInfo, err := b.rpc.GetL2BlockInfoV2(ctx, new(big.Int).SetUint64(slotB.NumBlocks-1))
+			if err != nil {
+				return nil, err
+			}
+
+			params.ParentMetaHash = blockInfo.MetaHash
+		}
+
+		encodedParams, err := encoding.EncodeBlockParamsOntake(params)
 		if err != nil {
 			return nil, err
 		}