X-Git-Url: https://git.novaco.in/?a=blobdiff_plain;f=Novacoin%2FCBlock.cs;h=8064b9dda76b1f0725788444a0b7d4dd850b3db7;hb=c76653cc18a1d1eb46977ea0e94e5394276f910a;hp=d80e68e81a7ae960e45df09dd72e0a3baec0f361;hpb=1dcac5faa2b1477034f82466ffb16170fa2e9bb6;p=NovacoinLibrary.git

diff --git a/Novacoin/CBlock.cs b/Novacoin/CBlock.cs
index d80e68e..8064b9d 100644
--- a/Novacoin/CBlock.cs
+++ b/Novacoin/CBlock.cs
@@ -199,13 +199,13 @@ namespace Novacoin
                 }
 
                 // Check timestamp
-                if (header.nTime > NetUtils.FutureDrift(NetUtils.GetAdjustedTime()))
+                if (header.nTime > NetInfo.FutureDrift(NetInfo.GetAdjustedTime()))
                 {
                     return false;
                 }
 
                 // Check coinbase timestamp
-                if (header.nTime < NetUtils.PastDrift(vtx[0].nTime))
+                if (header.nTime < NetInfo.PastDrift(vtx[0].nTime))
                 {
                     return false;
                 }
@@ -271,7 +271,22 @@ namespace Novacoin
 
         private bool CheckProofOfWork(uint256 hash, uint nBits)
         {
-            // TODO: stub!
+            uint256 nTarget = new uint256();
+            nTarget.Compact = nBits;
+
+            // Check range
+            if (nTarget > NetInfo.nProofOfWorkLimit)
+            {
+                // nBits below minimum work
+                return false; 
+            }
+
+            // Check proof of work matches claimed amount
+            if (hash > nTarget)
+            {
+                //  hash doesn't match nBits
+                return false;
+            }
 
             return true;
         }
@@ -366,18 +381,18 @@ namespace Novacoin
         /// <summary>
         /// Serialized size
         /// </summary>
-        public int Size
+        public uint Size
         {
             get
             {
-                int nSize = 80 + VarInt.GetEncodedSize(vtx.Length); // CBlockHeader + NumTx
+                uint nSize = 80 + VarInt.GetEncodedSize(vtx.Length); // CBlockHeader + NumTx
 
                 foreach (var tx in vtx)
                 {
                     nSize += tx.Size;
                 }
 
-                nSize += VarInt.GetEncodedSize(signature.Length) + signature.Length;
+                nSize += VarInt.GetEncodedSize(signature.Length) + (uint)signature.Length;
 
                 return nSize;
             }
@@ -388,11 +403,11 @@ namespace Novacoin
         /// </summary>
         /// <param name="nTx">Transaction index.</param>
         /// <returns>Offset in bytes from the beginning of block header.</returns>
-        public int GetTxOffset(int nTx)
+        public uint GetTxOffset(int nTx)
         {
             Contract.Requires<ArgumentException>(nTx >= 0 && nTx < vtx.Length, "Transaction index you've specified is incorrect.");
 
-            int nOffset = 80 + VarInt.GetEncodedSize(vtx.Length); // CBlockHeader + NumTx
+            uint nOffset = 80 + VarInt.GetEncodedSize(vtx.Length); // CBlockHeader + NumTx
 
             for (int i = 0; i < nTx; i++)
             {
@@ -455,6 +470,130 @@ namespace Novacoin
             
             return sb.ToString();
         }
-	}
+
+        /// <summary>
+        /// Calculate proof-of-work reward.
+        /// </summary>
+        /// <param name="nBits">Packed difficulty representation.</param>
+        /// <param name="nFees">Amount of fees.</param>
+        /// <returns>Reward value.</returns>
+        public static ulong GetProofOfWorkReward(uint nBits, ulong nFees)
+        {
+            // NovaCoin: subsidy is cut in half every 64x multiply of PoW difficulty
+            // A reasonably continuous curve is used to avoid shock to market
+            // (nSubsidyLimit / nSubsidy) ** 6 == bnProofOfWorkLimit / bnTarget
+            //
+            // Human readable form:
+            //
+            // nSubsidy = 100 / (diff ^ 1/6)
+            //
+            // Please note that we're using bisection to find an approximate solutuion
+
+
+            uint256 nTarget = 0;
+            nTarget.Compact = nBits;
+
+            BigNum bnTarget = nTarget;
+            BigNum bnTargetLimit = NetInfo.nProofOfWorkLimit;
+
+            BigNum bnSubsidyLimit = NetInfo.nMaxMintProofOfWork;
+            BigNum bnLowerBound = CTransaction.nCent;
+            BigNum bnUpperBound = bnSubsidyLimit;
+
+            while (bnLowerBound + CTransaction.nCent <= bnUpperBound)
+            {
+                BigNum bnMidValue = (bnLowerBound + bnUpperBound) / 2;
+                if (bnMidValue * bnMidValue * bnMidValue * bnMidValue * bnMidValue * bnMidValue * bnTargetLimit > bnSubsidyLimit * bnSubsidyLimit * bnSubsidyLimit * bnSubsidyLimit * bnSubsidyLimit * bnSubsidyLimit * bnTarget)
+                    bnUpperBound = bnMidValue;
+                else
+                    bnLowerBound = bnMidValue;
+            }
+
+            ulong nSubsidy = bnUpperBound;
+            nSubsidy = (nSubsidy / CTransaction.nCent) * CTransaction.nCent;
+
+            return Math.Min(nSubsidy, NetInfo.nMaxMintProofOfWork) + nFees;
+        }
+
+        public static ulong GetProofOfStakeReward(ulong nCoinAge, uint nBits, uint nTime)
+        {
+            ulong nRewardCoinYear, nSubsidy, nSubsidyLimit = 10 * CTransaction.nCoin;
+
+            if (nTime > NetInfo.nDynamicStakeRewardTime)
+            {
+                // Stage 2 of emission process is PoS-based. It will be active on mainNet since 20 Jun 2013.
+
+                BigNum bnRewardCoinYearLimit = NetInfo.nMaxMintProofOfStake; // Base stake mint rate, 100% year interest
+
+                uint256 nTarget = 0;
+                nTarget.Compact = nBits;
+
+                BigNum bnTarget = nTarget;
+                BigNum bnTargetLimit = NetInfo.GetProofOfStakeLimit(0, nTime);
+
+                // NovaCoin: A reasonably continuous curve is used to avoid shock to market
+
+                BigNum bnLowerBound = CTransaction.nCent, // Lower interest bound is 1% per year
+                    bnUpperBound = bnRewardCoinYearLimit, // Upper interest bound is 100% per year
+                    bnMidPart, bnRewardPart;
+
+                while (bnLowerBound + CTransaction.nCent <= bnUpperBound)
+                {
+                    BigNum bnMidValue = (bnLowerBound + bnUpperBound) / 2;
+                    if (nTime < NetInfo.nStakeCurveSwitchTime)
+                    {
+                        //
+                        // Until 20 Oct 2013: reward for coin-year is cut in half every 64x multiply of PoS difficulty
+                        //
+                        // (nRewardCoinYearLimit / nRewardCoinYear) ** 6 == bnProofOfStakeLimit / bnTarget
+                        //
+                        // Human readable form: nRewardCoinYear = 1 / (posdiff ^ 1/6)
+                        //
+
+                        bnMidPart = bnMidValue * bnMidValue * bnMidValue * bnMidValue * bnMidValue * bnMidValue;
+                        bnRewardPart = bnRewardCoinYearLimit * bnRewardCoinYearLimit * bnRewardCoinYearLimit * bnRewardCoinYearLimit * bnRewardCoinYearLimit * bnRewardCoinYearLimit;
+                    }
+                    else
+                    {
+                        //
+                        // Since 20 Oct 2013: reward for coin-year is cut in half every 8x multiply of PoS difficulty
+                        //
+                        // (nRewardCoinYearLimit / nRewardCoinYear) ** 3 == bnProofOfStakeLimit / bnTarget
+                        //
+                        // Human readable form: nRewardCoinYear = 1 / (posdiff ^ 1/3)
+                        //
+
+                        bnMidPart = bnMidValue * bnMidValue * bnMidValue;
+                        bnRewardPart = bnRewardCoinYearLimit * bnRewardCoinYearLimit * bnRewardCoinYearLimit;
+                    }
+
+                    if (bnMidPart * bnTargetLimit > bnRewardPart * bnTarget)
+                        bnUpperBound = bnMidValue;
+                    else
+                        bnLowerBound = bnMidValue;
+                }
+
+                nRewardCoinYear = bnUpperBound;
+                nRewardCoinYear = Math.Min((nRewardCoinYear / CTransaction.nCent) * CTransaction.nCent, NetInfo.nMaxMintProofOfStake);
+            }
+            else
+            {
+                // Old creation amount per coin-year, 5% fixed stake mint rate
+                nRewardCoinYear = 5 * CTransaction.nCent;
+            }
+
+            nSubsidy = nCoinAge * nRewardCoinYear * 33 / (365 * 33 + 8);
+
+            // Set reasonable reward limit for large inputs since 20 Oct 2013
+            //
+            // This will stimulate large holders to use smaller inputs, that's good for the network protection
+            if (NetInfo.nStakeCurveSwitchTime < nTime)
+            {
+                nSubsidy = Math.Min(nSubsidy, nSubsidyLimit);
+            }
+
+            return nSubsidy;
+        }
+    }
 }