From 21c4cc932a340f18f72460869ff23a42e8ff8eee Mon Sep 17 00:00:00 2001
From: Jim8y <jimmy@r3e.network>
Date: Sun, 31 Dec 2023 12:01:04 +0800
Subject: [PATCH] add previous block state to the block header

---
 src/Neo/Network/P2P/Payloads/Block.cs  |  5 +++++
 src/Neo/Network/P2P/Payloads/Header.cs | 11 +++++++++++
 2 files changed, 16 insertions(+)

diff --git a/src/Neo/Network/P2P/Payloads/Block.cs b/src/Neo/Network/P2P/Payloads/Block.cs
index 955bf98bf6..8584814d4e 100644
--- a/src/Neo/Network/P2P/Payloads/Block.cs
+++ b/src/Neo/Network/P2P/Payloads/Block.cs
@@ -46,6 +46,11 @@ public sealed class Block : IEquatable<Block>, IInventory
         /// </summary>
         public UInt256 PrevHash => Header.PrevHash;
 
+        /// <summary>
+        /// The state root of the previous block.
+        /// </summary>
+        public UInt256 PrevState => Header.PrevState;
+
         /// <summary>
         /// The merkle root of the transactions.
         /// </summary>
diff --git a/src/Neo/Network/P2P/Payloads/Header.cs b/src/Neo/Network/P2P/Payloads/Header.cs
index d971ac2aaa..22a9af89d4 100644
--- a/src/Neo/Network/P2P/Payloads/Header.cs
+++ b/src/Neo/Network/P2P/Payloads/Header.cs
@@ -27,6 +27,7 @@ public sealed class Header : IEquatable<Header>, IVerifiable
     {
         private uint version;
         private UInt256 prevHash;
+        private UInt256 prevState;
         private UInt256 merkleRoot;
         private ulong timestamp;
         private ulong nonce;
@@ -57,6 +58,12 @@ public UInt256 PrevHash
             set { prevHash = value; _hash = null; }
         }
 
+        public UInt256 PrevState
+        {
+            get => prevState;
+            set { prevState = value; }
+        }
+
         /// <summary>
         /// The merkle root of the transactions.
         /// </summary>
@@ -127,6 +134,7 @@ public UInt256 Hash
         public int Size =>
             sizeof(uint) +      // Version
             UInt256.Length +    // PrevHash
+            UInt256.Length +    // PrevState
             UInt256.Length +    // MerkleRoot
             sizeof(ulong) +     // Timestamp
             sizeof(ulong) +      // Nonce
@@ -162,6 +170,7 @@ void IVerifiable.DeserializeUnsigned(ref MemoryReader reader)
             version = reader.ReadUInt32();
             if (version > 0) throw new FormatException();
             prevHash = reader.ReadSerializable<UInt256>();
+            prevState = reader.ReadSerializable<UInt256>();
             merkleRoot = reader.ReadSerializable<UInt256>();
             timestamp = reader.ReadUInt64();
             nonce = reader.ReadUInt64();
@@ -205,6 +214,7 @@ void IVerifiable.SerializeUnsigned(BinaryWriter writer)
         {
             writer.Write(version);
             writer.Write(prevHash);
+            writer.Write(prevState);
             writer.Write(merkleRoot);
             writer.Write(timestamp);
             writer.Write(nonce);
@@ -225,6 +235,7 @@ public JObject ToJson(ProtocolSettings settings)
             json["size"] = Size;
             json["version"] = version;
             json["previousblockhash"] = prevHash.ToString();
+            json["previousblockstate"] = prevState.ToString();
             json["merkleroot"] = merkleRoot.ToString();
             json["time"] = timestamp;
             json["nonce"] = nonce.ToString("X16");