Change Difficulty type to long

Libplanet.Tests/Blockchain/BlockChainTest.cs

@@ -370,7 +370,7 @@ public NullPolicy(InvalidBlockException exceptionToThrow = null)
                 _exceptionToThrow = exceptionToThrow;
             }
 
-            public int GetNextBlockDifficulty(IReadOnlyList<Block<T>> blocks) =>
+            public long GetNextBlockDifficulty(IReadOnlyList<Block<T>> blocks) =>
                 blocks.Any() ? 1 : 0;
 
             public InvalidBlockException ValidateNextBlock(

Libplanet.Tests/Blockchain/Policies/BlockPolicyTest.cs

@@ -352,9 +352,9 @@ private IEnumerable<Block<DumbAction>> MineBlocks(
             var miner = default(Address);
             long i = 0;
             HashDigest<SHA256>? previousHash = null;
-            foreach ((int timestampHour, int d) in blockArgs)
+            foreach ((int timestampHour, long d) in blockArgs)
             {
-                int difficulty = d;
+                long difficulty = d;
                 var timestamp =
                     FixtureEpoch + TimeSpan.FromHours(timestampHour);
                 if (interprocess != null)
@@ -398,7 +398,7 @@ private IEnumerable<Block<DumbAction>> MineBlocks(
         private struct BlockFields
         {
             internal long Index;
-            internal int Difficulty;
+            internal long Difficulty;
             internal HashDigest<SHA256>? PreviousHash;
             internal DateTimeOffset Timestamp;
         }

Libplanet.Tests/HashcashTest.cs

@@ -11,7 +11,7 @@ public class HashcashTest
     {
         [Theory]
         [ClassData(typeof(HashcashTestData))]
-        public void AnswerLessThanTarget(byte[] challenge, int difficulty)
+        public void AnswerLessThanTarget(byte[] challenge, long difficulty)
         {
             byte[] Stamp(Nonce nonce) => challenge.Concat(nonce.ToByteArray()).ToArray();
             var answer = Hashcash.Answer(Stamp, difficulty);
@@ -24,10 +24,10 @@ public void TestBytesWithDifficulty()
         {
             Assert.True(LessThanTarget(new byte[1] { 0x80 }, 0));
             Assert.False(LessThanTarget(new byte[1] { 0x80 }, 2));
-            int[] difficulties = Enumerable.Range(1, 8)
-                .Select(x => (int)Math.Pow(2, x)).ToArray();
+            long[] difficulties = Enumerable.Range(1, 8)
+                .Select(x => (long)Math.Pow(2, x)).ToArray();
 
-            foreach (int difficulty in difficulties)
+            foreach (long difficulty in difficulties)
             {
                 Assert.True(LessThanTarget(new byte[2] { 0x00, 0x80 }, difficulty));
             }
@@ -38,7 +38,7 @@ public void TestBytesWithDifficulty()
             Assert.True(LessThanTarget(new byte[2] { 0x00, 0x20 }, 1024));
         }
 
-        private bool LessThanTarget(byte[] bytes, int difficulty)
+        private bool LessThanTarget(byte[] bytes, long difficulty)
         {
             byte[] digest;
             if (bytes.Length < HashDigest<SHA256>.Size)

Libplanet.Tests/TestUtils.cs

@@ -107,7 +107,7 @@ internal static Block<T> MineNext<T>(
             }
 
             const long index = 1;
-            const int difficulty = 1;
+            const long difficulty = 1;
             HashDigest<SHA256> previousHash = previousBlock.Hash;
             DateTimeOffset timestamp = previousBlock.Timestamp.AddDays(1);
             Address miner = previousBlock.Miner.Value;

Libplanet/Blockchain/BlockChain.cs

@@ -306,7 +306,7 @@ DateTimeOffset currentTime
         {
             string @namespace = Id.ToString();
             long index = Store.CountIndex(@namespace);
-            int difficulty = Policy.GetNextBlockDifficulty(this);
+            long difficulty = Policy.GetNextBlockDifficulty(this);
             HashDigest<SHA256>? prevHash = Store.IndexBlockHash(
                 @namespace,
                 index - 1

Libplanet/Blockchain/Policies/BlockPolicy.cs

@@ -64,7 +64,7 @@ public InvalidBlockException ValidateNextBlock(
             Block<T> nextBlock)
         {
             int index = blocks.Count;
-            int difficulty = GetNextBlockDifficulty(blocks);
+            long difficulty = GetNextBlockDifficulty(blocks);
 
             Block<T> lastBlock = index >= 1 ? blocks[index - 1] : null;
             HashDigest<SHA256>? prevHash = lastBlock?.Hash;
@@ -113,9 +113,9 @@ public InvalidBlockException ValidateNextBlock(
         }
 
         /// <inheritdoc />
-        public int GetNextBlockDifficulty(IReadOnlyList<Block<T>> blocks)
+        public long GetNextBlockDifficulty(IReadOnlyList<Block<T>> blocks)
         {
-            const int minDifficulty = 1024;
+            const long minDifficulty = 1024;
             const int difficultyBoundDivisor = 512;
 
             int index = blocks.Count;
@@ -130,15 +130,15 @@ public int GetNextBlockDifficulty(IReadOnlyList<Block<T>> blocks)
             DateTimeOffset prevPrevTimestamp = blocks[index - 2].Timestamp;
             DateTimeOffset prevTimestamp = prevBlock.Timestamp;
             TimeSpan timeDiff = prevTimestamp - prevPrevTimestamp;
-            int timeDiffMilliseconds = (int)timeDiff.TotalMilliseconds;
-            int multiplier = Math.Max(
+            long timeDiffMilliseconds = (long)timeDiff.TotalMilliseconds;
+            long multiplier = Math.Max(
                 1 - (timeDiffMilliseconds /
-                     (int)BlockInterval.TotalMilliseconds),
+                     (long)BlockInterval.TotalMilliseconds),
                 -99);
 
             var prevDifficulty = prevBlock.Difficulty;
             var offset = prevDifficulty / difficultyBoundDivisor;
-            int nextDifficulty = prevDifficulty + (offset * multiplier);
+            long nextDifficulty = prevDifficulty + (offset * multiplier);
 
             return Math.Max(nextDifficulty, minDifficulty);
         }

Libplanet/Blockchain/Policies/IBlockPolicy.cs

@@ -42,6 +42,6 @@ InvalidBlockException ValidateNextBlock(
         /// followed by a new <see cref="Block{T}"/> to be mined.</param>
         /// <returns>A right <see cref="Block{T}.Difficulty"/>
         /// for a new <see cref="Block{T}"/> to be mined.</returns>
-        int GetNextBlockDifficulty(IReadOnlyList<Block<T>> blocks);
+        long GetNextBlockDifficulty(IReadOnlyList<Block<T>> blocks);
     }
 }

Libplanet/Blocks/Block.cs

@@ -25,7 +25,7 @@ public partial class Block<T> : ISerializable
 
         public Block(
             long index,
-            int difficulty,
+            long difficulty,
             Nonce nonce,
             Address? miner,
             HashDigest<SHA256>? previousHash,
@@ -84,7 +84,7 @@ public HashDigest<SHA256> Hash
         public long Index { get; }
 
         [Uno.EqualityIgnore]
-        public int Difficulty { get; }
+        public long Difficulty { get; }
 
         [Uno.EqualityIgnore]
         public Nonce Nonce { get; }
@@ -103,7 +103,7 @@ public HashDigest<SHA256> Hash
 
         public static Block<T> Mine(
             long index,
-            int difficulty,
+            long difficulty,
             Address miner,
             HashDigest<SHA256>? previousHash,
             DateTimeOffset timestamp,

Libplanet/Blocks/RawBlock.cs

@@ -11,7 +11,7 @@ public RawBlock(
             string timestamp,
             byte[] nonce,
             byte[] miner,
-            int difficulty,
+            long difficulty,
             byte[] previousHash,
             IEnumerable transactions)
             : this(
@@ -32,7 +32,7 @@ public RawBlock(
             string timestamp,
             byte[] nonce,
             byte[] miner,
-            int difficulty,
+            long difficulty,
             byte[] previousHash,
             IEnumerable transactions,
             byte[] hash)
@@ -72,7 +72,7 @@ internal RawBlock(SerializationInfo info, StreamingContext context)
 
         public byte[] Miner { get; }
 
-        public int Difficulty { get; }
+        public long Difficulty { get; }
 
         public byte[] PreviousHash { get; }
 

Libplanet/HashDigest.cs

@@ -156,7 +156,7 @@ public static HashDigest<T> FromString(string hexDigest)
         /// <c>true</c>.
         /// </returns>
         [Pure]
-        public bool LessThanTarget(int difficulty)
+        public bool LessThanTarget(long difficulty)
         {
             if (difficulty == 0)
             {

Libplanet/Hashcash.cs

@@ -21,12 +21,12 @@ public static class Hashcash
         /// should not vary for different <paramref name="nonce"/>s.</para>
         /// </summary>
         /// <param name="nonce">An arbitrary nonce for an attempt, provided
-        /// by <see cref="Hashcash.Answer(Stamp, int)"/> method.</param>
+        /// by <see cref="Hashcash.Answer(Stamp, long)"/> method.</param>
         /// <returns>A <see cref="byte"/> array determined from the given
         /// <paramref name="nonce"/>.  It should return consistently
         /// an equivalent array for equivalent <paramref name="nonce"/>
         /// values.</returns>
-        /// <seealso cref="Hashcash.Answer(Stamp, int)"/>
+        /// <seealso cref="Hashcash.Answer(Stamp, long)"/>
         /// <seealso cref="Nonce"/>
         public delegate byte[] Stamp(Nonce nonce);
 
@@ -45,7 +45,7 @@ public static class Hashcash
         /// <returns>A <see cref="Nonce"/> value which satisfies the given
         /// <paramref name="difficulty"/>.</returns>
         /// <seealso cref="Stamp"/>
-        public static Nonce Answer(Stamp stamp, int difficulty)
+        public static Nonce Answer(Stamp stamp, long difficulty)
         {
             var nonceBytes = new byte[10];
             var random = new Random();