fix: GetProjectedMNPayees should take care of the block index it's using to check mn_rr internally

This ensures consitensy between pindex and the height of the mn list itself.

Also try to guess mn_rr activation status at nHeight if possible

Author: UdjinM6

src/evo/deterministicmns.cpp

@@ -214,16 +214,41 @@ CDeterministicMNCPtr CDeterministicMNList::GetMNPayee(const CBlockIndex* pIndex)
     return best;
 }
 
-std::vector<CDeterministicMNCPtr> CDeterministicMNList::GetProjectedMNPayeesAtChainTip(int nCount) const
-{
-    return GetProjectedMNPayees(::ChainActive()[nHeight], nCount);
-}
-
-std::vector<CDeterministicMNCPtr> CDeterministicMNList::GetProjectedMNPayees(const CBlockIndex* const pindex, int nCount) const
+std::vector<CDeterministicMNCPtr> CDeterministicMNList::GetProjectedMNPayees(int nCount) const
 {
     if (nCount < 0 ) {
         return {};
     }
+
+    bool isMNRewardReallocation{false};
+    if (auto pindex = ::ChainActive()[nHeight]; pindex == nullptr) {
+        // Something went wrong, probably a race condition in tip and mnlist updates,
+        // try ecovering...
+        pindex = ::ChainActive().Tip();
+        const auto mn_rr_state = llmq::utils::GetMNRewardReallocationState(pindex);
+        isMNRewardReallocation = (mn_rr_state == ThresholdState::ACTIVE);
+        if (!isMNRewardReallocation) {
+            const auto w_size = static_cast<int>(Params().GetConsensus().vDeployments[Consensus::DEPLOYMENT_MN_RR].nWindowSize);
+            // Check if mn_rr is going to be active at nHeight
+            if (mn_rr_state == ThresholdState::LOCKED_IN) {
+                int activation_height = llmq::utils::GetMNRewardReallocationSince(pindex) + w_size;
+                if (nHeight >= activation_height) {
+                    isMNRewardReallocation = true;
+                }
+            } else {
+                if (nHeight - pindex->nHeight > w_size) {
+                    // Should never happen, can't do anything
+                    return {};
+                }
+                // No way we reach mn_rr activation if it's not locked in yet
+                // and height diff is less than or equal w_size, so isMNRewardReallocation == false
+                // but it's safe to continue nevertheless.
+            }
+        }
+    } else {
+        isMNRewardReallocation = llmq::utils::IsMNRewardReallocationActive(pindex);
+    }
+
     nCount = std::min(nCount, int(GetValidWeightedMNsCount()));
 
     std::vector<CDeterministicMNCPtr> result;

src/evo/deterministicmns.h

@@ -347,8 +347,7 @@ class CDeterministicMNList
      * @param nCount the number of payees to return. "nCount = max()"" means "all", use it to avoid calling GetValidWeightedMNsCount twice.
      * @return
      */
-    [[nodiscard]] std::vector<CDeterministicMNCPtr> GetProjectedMNPayees(const CBlockIndex* const pindex, int nCount = std::numeric_limits<int>::max()) const;
-    [[nodiscard]] std::vector<CDeterministicMNCPtr> GetProjectedMNPayeesAtChainTip(int nCount = std::numeric_limits<int>::max()) const;
+    [[nodiscard]] std::vector<CDeterministicMNCPtr> GetProjectedMNPayees(int nCount = std::numeric_limits<int>::max()) const;
 
     /**
      * Calculate a quorum based on the modifier. The resulting list is deterministically sorted by score

src/governance/governance.cpp

@@ -676,7 +676,7 @@ void CGovernanceManager::CreateGovernanceTrigger(const CSuperblock& sb, CConnman
         // Nobody submitted a trigger we'd like to see,
         // so let's do it but only if we are the payee
         auto mnList = deterministicMNManager->GetListAtChainTip();
-        auto mn_payees = mnList.GetProjectedMNPayeesAtChainTip();
+        auto mn_payees = mnList.GetProjectedMNPayees();
         if (mn_payees.empty()) return;
         {
             LOCK(activeMasternodeInfoCs);

src/rpc/masternode.cpp

@@ -136,7 +136,7 @@ static UniValue masternode_count(const JSONRPCRequest& request)
 static UniValue GetNextMasternodeForPayment(int heightShift)
 {
     auto mnList = deterministicMNManager->GetListAtChainTip();
-    auto payees = mnList.GetProjectedMNPayeesAtChainTip(heightShift);
+    auto payees = mnList.GetProjectedMNPayees(heightShift);
     if (payees.empty())
         return "unknown";
     auto payee = payees.back();
@@ -360,7 +360,7 @@ static UniValue masternode_winners(const JSONRPCRequest& request, const Chainsta
         obj.pushKV(strprintf("%d", h), strPayments);
     }
 
-    auto projection = deterministicMNManager->GetListForBlock(pindexTip).GetProjectedMNPayees(pindexTip, 20);
+    auto projection = deterministicMNManager->GetListForBlock(pindexTip).GetProjectedMNPayees(20);
     for (size_t i = 0; i < projection.size(); i++) {
         int h = nChainTipHeight + 1 + i;
         std::string strPayments = GetRequiredPaymentsString(h, projection[i]);