Refactor transaction logging in BlockAssembler

- Updated logging categories from STAKEMODIF to SELECTCOINS for better clarity in transaction handling.
- Added checks for spent coins and maturity of previous outputs in the TestTransaction method, enhancing transaction validation.
- Improved logging for skipped transactions in both TestTransaction and TestPackageTransactions methods, providing more detailed insights into transaction processing decisions.

These changes aim to improve the debugging process and ensure more robust transaction validation within the mining workflow.

src/miner.cpp

@@ -239,7 +239,7 @@ bool BlockAssembler::TestTransaction(const CTransactionRef& tx, PocketBlockRef&
     // Payload should be in operative table Transactions
     if (!ptx)
     {
-        LogPrint(BCLog::STAKEMODIF, "Warning: build block skip transaction %s with result 'NOT FOUND'\n",
+        LogPrint(BCLog::SELECTCOINS, "Warning: build block skip transaction %s with result 'NOT FOUND'\n",
             tx->GetHash().GetHex());
 
         return false;
@@ -248,7 +248,7 @@ bool BlockAssembler::TestTransaction(const CTransactionRef& tx, PocketBlockRef&
     // Check consensus
     if (auto[ok, result] = PocketConsensus::SocialConsensusHelper::Check(tx, ptx, ChainActive().Height() + 1); !ok)
     {
-        LogPrint(BCLog::STAKEMODIF, "Warning: build block skip transaction %s with check result %d\n",
+        LogPrint(BCLog::SELECTCOINS, "Warning: build block skip transaction %s with check result %d\n",
             tx->GetHash().GetHex(), (int) result);
 
         return false;
@@ -257,11 +257,30 @@ bool BlockAssembler::TestTransaction(const CTransactionRef& tx, PocketBlockRef&
     // Validate consensus
     if (auto[ok, result] = PocketConsensus::SocialConsensusHelper::Validate(tx, ptx, pblockTemplate, ChainActive().Height() + 1); !ok)
     {
-        LogPrint(BCLog::STAKEMODIF, "Warning: build block skip transaction %s with validate result %d\n",
+        LogPrint(BCLog::SELECTCOINS, "Warning: build block skip transaction %s with validate result %d\n",
             tx->GetHash().GetHex(), (int) result);
 
         return false;
     }
+
+    CCoinsViewCache view(&::ChainstateActive().CoinsTip());
+    for (unsigned int i = 0; i < tx->vin.size(); ++i) {
+        const COutPoint &prevout = tx->vin[i].prevout;
+        const Coin& coin = view.AccessCoin(prevout);
+        if (coin.IsSpent())
+        {
+            LogPrint(BCLog::SELECTCOINS, "Warning: build block skip transaction: tx - %s, prev - %s is spent\n", tx->GetHash().GetHex(), prevout.hash.GetHex());
+            return false;
+        }
+
+        // If prev is pocketnet, check that it's matured
+        if (ChainActive().Height() + 1 - coin.nHeight < POCKETNET_MATURITY)
+        {
+            LogPrint(BCLog::SELECTCOINS, "Warning: build block skip transaction: tx - %s, prev - %s, %d - %d = %d < %d\n",
+                tx->GetHash().GetHex(), prevout.hash.GetHex(), ChainActive().Height() + 1, coin.nHeight, ChainActive().Height() + 1 - coin.nHeight, POCKETNET_MATURITY);
+            return false;
+        }
+    }
 
     // All is good - save for descendants
     pblockTemplate->push_back(ptx);
@@ -289,10 +308,12 @@ bool BlockAssembler::TestPackageTransactions(const CTxMemPool::setEntries& packa
     {
         if (!IsFinalTx(it->GetTx(), nHeight, nLockTimeCutoff))
         {
+            LogPrint(BCLog::SELECTCOINS, "Warning: build block skip transaction: tx - %s, height - %d, locktime - %d\n", it->GetTx().GetHash().GetHex(), nHeight, nLockTimeCutoff);
             return false;
         }
         if (!fIncludeWitness && it->GetTx().HasWitness())
         {
+            LogPrint(BCLog::SELECTCOINS, "Warning: build block skip transaction: tx - %s, height - %d, HasWitness\n", it->GetTx().GetHash().GetHex(), nHeight);
             return false;
         }
     }
@@ -473,7 +494,7 @@ void BlockAssembler::addPackageTxs(int& nPackagesSelected, int& nDescendantsUpda
 
         if (packageFees < minFee)
         {
-            LogPrintf("tx - %s, fee - %s, minFee - %s\n", iter->GetTx().GetHash().GetHex(), packageFees, minFee);
+            LogPrint(BCLog::SELECTCOINS, "Warning: build block skip transaction %s, fee (%s) < minFee (%s)\n", iter->GetTx().GetHash().GetHex(), packageFees, minFee);
 
             if (fUsingModified)
             {