Update DFI DUSD vault collateral requirement rules

src/chainparams.cpp

@@ -137,7 +137,7 @@ class CMainParams : public CChainParams {
         consensus.FortCanningCrunchHeight = 1936000; // June 2, 2022.
         consensus.FortCanningSpringHeight = 2033000; // July 6, 2022.
         consensus.FortCanningGreatWorldHeight = 2212000; // Sep 7th, 2022.
-        consensus.FortCanningEpilogueHeight = std::numeric_limits<int>::max();
+        consensus.FortCanningEpilogueHeight = 2218000;
 
         consensus.pos.diffLimit = uint256S("00000fffffffffffffffffffffffffffffffffffffffffffffffffffffffffff");
 //        consensus.pos.nTargetTimespan = 14 * 24 * 60 * 60; // two weeks
@@ -376,7 +376,7 @@ class CTestNetParams : public CChainParams {
         consensus.FortCanningCrunchHeight = 1011600;
         consensus.FortCanningSpringHeight = 1086000;
         consensus.FortCanningGreatWorldHeight = 1223000;
-        consensus.FortCanningEpilogueHeight = std::numeric_limits<int>::max();
+        consensus.FortCanningEpilogueHeight = 1233000;
 
         consensus.pos.diffLimit = uint256S("00000fffffffffffffffffffffffffffffffffffffffffffffffffffffffffff");
 //        consensus.pos.nTargetTimespan = 14 * 24 * 60 * 60; // two weeks

src/init.cpp

@@ -503,7 +503,7 @@ void SetupServerArgs()
     gArgs.AddArg("-fortcanningspringheight", "Fort Canning Spring fork activation height (regtest only)", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::CHAINPARAMS);
     gArgs.AddArg("-fortcanninggreatworldheight", "Fort Canning Great World fork activation height (regtest only)", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::CHAINPARAMS);
     gArgs.AddArg("-greatworldheight", "Alias for Fort Canning Great World fork activation height (regtest only)", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::CHAINPARAMS);
-    gArgs.AddArg("-fortcanningepilogueheight", "Alias for Fort Canning Epilogue fork activation height (regtest only)", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::CHAINPARAMS);
+    gArgs.AddArg("-fortcanningepilogueheight", "Fort Canning Epilogue fork activation height (regtest only)", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::CHAINPARAMS);
     gArgs.AddArg("-jellyfish_regtest", "Configure the regtest network for jellyfish testing", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::OPTIONS);
     gArgs.AddArg("-simulatemainnet", "Configure the regtest network to mainnet target timespan and spacing ", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::OPTIONS);
     gArgs.AddArg("-dexstats", strprintf("Enable storing live dex data in DB (default: %u)", DEFAULT_DEXSTATS), ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);

src/masternodes/mn_checks.cpp

@@ -26,6 +26,8 @@
 
 #include <algorithm>
 
+constexpr std::string_view ERR_STRING_DUSD_USAGE = "DUSD can either be used as collateral or loaned, but not both at the same time after Fort Canning Epilogue";
+
 std::string ToString(CustomTxType type) {
     switch (type)
     {
@@ -2943,6 +2945,25 @@ class CCustomTxApplyVisitor : public CCustomTxVisitor
         return mnview.UpdateVault(obj.vaultId, *vault);
     }
 
+    Res CollateralAddVerifyDUSDUsage(DCT_ID collateralInToken, const CCollateralLoans& colleteralLoans) const {
+        if (static_cast<int>(height) < consensus.FortCanningEpilogueHeight)
+            return Res::Ok();
+
+        auto tokenDUSD = mnview.GetToken("DUSD");
+        if (!tokenDUSD)
+            return Res::Err("DUSD token not found");
+
+        if (collateralInToken != tokenDUSD->first)
+            return Res::Ok();
+
+        for (const auto& item : colleteralLoans.loans) {
+            if (item.nTokenId == tokenDUSD->first) {
+                return Res::Err(std::string(ERR_STRING_DUSD_USAGE));
+            }
+        }
+        return Res::Ok();
+    }
+
     Res operator()(const CDepositToVaultMessage& obj) const {
         auto res = CheckCustomTx();
         if (!res)
@@ -2976,15 +2997,16 @@ class CCustomTxApplyVisitor : public CCustomTxVisitor
             return Res::Err("Insufficient funds: can't subtract balance of %s: %s\n", ScriptToString(obj.from), res.msg);
 
         res = mnview.AddVaultCollateral(obj.vaultId, obj.amount);
-        if (!res)
-            return res;
+        if (!res) return res;
 
         bool useNextPrice = false, requireLivePrice = false;
         auto collaterals = mnview.GetVaultCollaterals(obj.vaultId);
 
         auto collateralsLoans = mnview.GetLoanCollaterals(obj.vaultId, *collaterals, height, time, useNextPrice, requireLivePrice);
-        if (!collateralsLoans)
-            return std::move(collateralsLoans);
+        if (!collateralsLoans) return std::move(collateralsLoans);
+
+        res = CollateralAddVerifyDUSDUsage(obj.amount.nTokenId, collateralsLoans);
+        if (!res) return res;
 
         auto scheme = mnview.GetLoanScheme(vault->schemeId);
         if (collateralsLoans.val->ratio() < scheme->ratio)
@@ -3018,10 +3040,22 @@ class CCustomTxApplyVisitor : public CCustomTxVisitor
         if (!res)
             return res;
 
+        auto hasDUSDLoans = false;
+
+        std::optional<std::pair<DCT_ID, std::optional<CTokensView::CTokenImpl>>> tokenDUSD;
+        if (static_cast<int>(height) >= consensus.FortCanningRoadHeight) {
+            tokenDUSD = mnview.GetToken("DUSD");
+        }
+
         if (const auto loanAmounts = mnview.GetLoanTokens(obj.vaultId))
         {
             // Update negative interest in vault
             for (const auto& [tokenId, currentLoanAmount] : loanAmounts->balances) {
+
+                if (tokenDUSD && tokenId == tokenDUSD->first) {
+                    hasDUSDLoans = true;
+                }
+
                 const auto rate = mnview.GetInterestRate(obj.vaultId, tokenId, height);
                 assert(rate);
 
@@ -3039,14 +3073,12 @@ class CCustomTxApplyVisitor : public CCustomTxVisitor
                 }
 
                 mnview.ResetInterest(height, obj.vaultId, vault->schemeId, tokenId);
+
             }
 
             if (auto collaterals = mnview.GetVaultCollaterals(obj.vaultId))
             {
-                std::optional<std::pair<DCT_ID, std::optional<CTokensView::CTokenImpl>>> tokenDUSD;
-                if (static_cast<int>(height) >= consensus.FortCanningRoadHeight) {
-                    tokenDUSD = mnview.GetToken("DUSD");
-                }
+
                 const auto scheme = mnview.GetLoanScheme(vault->schemeId);
                 for (int i = 0; i < 2; i++) {
                     // check collaterals for active and next price
@@ -3059,17 +3091,29 @@ class CCustomTxApplyVisitor : public CCustomTxVisitor
                     if (collateralsLoans.val->ratio() < scheme->ratio)
                         return Res::Err("Vault does not have enough collateralization ratio defined by loan scheme - %d < %d", collateralsLoans.val->ratio(), scheme->ratio);
 
-                    uint64_t totalCollaterals = 0;
+                    uint64_t totalCollateralsDUSD = 0;
+                    uint64_t totalCollateralsDFI = 0;
+
+                    for (auto& col : collateralsLoans.val->collaterals){
+                        if (col.nTokenId == DCT_ID{0} ){
+                            totalCollateralsDFI += col.nValue;
+                        }
+                        if(tokenDUSD && col.nTokenId == tokenDUSD->first){
+                            totalCollateralsDUSD += col.nValue;
+                        }
+                    }
 
-                    for (auto& col : collateralsLoans.val->collaterals)
-                        if (col.nTokenId == DCT_ID{0}
-                        || (tokenDUSD && col.nTokenId == tokenDUSD->first))
-                            totalCollaterals += col.nValue;
+                    uint64_t totalCollaterals = totalCollateralsDUSD + totalCollateralsDFI;
 
-                    if (static_cast<int>(height) < consensus.FortCanningHillHeight) {
-                        if (totalCollaterals < collateralsLoans.val->totalCollaterals / 2)
+                    if (static_cast<int>(height) < consensus.FortCanningHillHeight
+                            && totalCollateralsDUSD < collateralsLoans.val->totalCollaterals / 2){
                             return Res::Err("At least 50%% of the collateral must be in DFI");
                     } else {
+                        if (hasDUSDLoans
+                                && arith_uint256(totalCollateralsDFI) * 100 < arith_uint256(collateralsLoans.val->totalLoans) * scheme->ratio / 2
+                                && static_cast<int>(height) >= consensus.FortCanningEpilogueHeight){
+                                return Res::Err("At least 50%% of the minimum required collateral must be in DFI");
+                        }
                         if (arith_uint256(totalCollaterals) * 100 < arith_uint256(collateralsLoans.val->totalLoans) * scheme->ratio / 2)
                             return static_cast<int>(height) < consensus.FortCanningRoadHeight ? Res::Err("At least 50%% of the minimum required collateral must be in DFI")
                                                                                               : Res::Err("At least 50%% of the minimum required collateral must be in DFI or DUSD");
@@ -3108,6 +3152,14 @@ class CCustomTxApplyVisitor : public CCustomTxVisitor
 
         const auto loanAmounts = mnview.GetLoanTokens(obj.vaultId);
 
+        auto hasDUSDLoans = false;
+
+        std::optional<std::pair<DCT_ID, std::optional<CTokensView::CTokenImpl>>> tokenDUSD;
+        if (static_cast<int>(height) >= consensus.FortCanningRoadHeight) {
+            tokenDUSD = mnview.GetToken("DUSD");
+        }
+
+
         uint64_t totalLoansActivePrice = 0, totalLoansNextPrice = 0;
         for (const auto& [tokenId, tokenAmount] : obj.amounts.balances)
         {
@@ -3121,6 +3173,10 @@ class CCustomTxApplyVisitor : public CCustomTxVisitor
             if (!loanToken->mintable)
                 return Res::Err("Loan cannot be taken on token with id (%s) as \"mintable\" is currently false",tokenId.ToString());
 
+            if (tokenDUSD && tokenId == tokenDUSD->first) {
+                hasDUSDLoans = true;
+            }
+
             // Calculate interest
             CAmount currentLoanAmount{};
             bool resetInterestToHeight{};
@@ -3133,14 +3189,14 @@ class CCustomTxApplyVisitor : public CCustomTxVisitor
                 const auto totalInterest = TotalInterest(*rate, height);
 
                 if (totalInterest < 0) {
-                    loanAmountChange = currentLoanAmount > std::abs(totalInterest) ? 
+                    loanAmountChange = currentLoanAmount > std::abs(totalInterest) ?
                         // Interest to decrease smaller than overall existing loan amount.
                         // So reduce interest from the borrowing principal. If this is negative,
-                        // we'll reduce from principal. 
-                        tokenAmount + totalInterest : 
+                        // we'll reduce from principal.
+                        tokenAmount + totalInterest :
                         // Interest to decrease is larger than old loan amount.
-                        // We reduce from the borrowing principal. If this is negative, 
-                        // we'll reduce from principal. 
+                        // We reduce from the borrowing principal. If this is negative,
+                        // we'll reduce from principal.
                         tokenAmount - currentLoanAmount;
                     resetInterestToHeight = true;
                 }
@@ -3201,10 +3257,6 @@ class CCustomTxApplyVisitor : public CCustomTxVisitor
                 return res;
         }
 
-        std::optional<std::pair<DCT_ID, std::optional<CTokensView::CTokenImpl>>> tokenDUSD;
-        if (static_cast<int>(height) >= consensus.FortCanningRoadHeight) {
-            tokenDUSD = mnview.GetToken("DUSD");
-        }
         auto scheme = mnview.GetLoanScheme(vault->schemeId);
         for (int i = 0; i < 2; i++) {
             // check ratio against current and active price
@@ -3217,17 +3269,28 @@ class CCustomTxApplyVisitor : public CCustomTxVisitor
             if (collateralsLoans.val->ratio() < scheme->ratio)
                 return Res::Err("Vault does not have enough collateralization ratio defined by loan scheme - %d < %d", collateralsLoans.val->ratio(), scheme->ratio);
 
-            uint64_t totalCollaterals = 0;
+            uint64_t totalCollateralsDUSD = 0;
+            uint64_t totalCollateralsDFI = 0;
 
-            for (auto& col : collateralsLoans.val->collaterals)
-                if (col.nTokenId == DCT_ID{0}
-                || (tokenDUSD && col.nTokenId == tokenDUSD->first))
-                    totalCollaterals += col.nValue;
+            for (auto& col : collateralsLoans.val->collaterals){
+                if (col.nTokenId == DCT_ID{0} ){
+                    totalCollateralsDFI += col.nValue;
+                }
+                if(tokenDUSD && col.nTokenId == tokenDUSD->first){
+                    totalCollateralsDUSD += col.nValue;
+                }
+            }
 
-            if (static_cast<int>(height) < consensus.FortCanningHillHeight) {
-                if (totalCollaterals < collateralsLoans.val->totalCollaterals / 2)
-                    return Res::Err("At least 50%% of the collateral must be in DFI when taking a loan.");
+            uint64_t totalCollaterals = totalCollateralsDUSD + totalCollateralsDFI;
+            if (static_cast<int>(height) < consensus.FortCanningHillHeight
+                && totalCollateralsDUSD < collateralsLoans.val->totalCollaterals / 2){
+                return Res::Err("At least 50%% of the collateral must be in DFI when taking a loan.");
             } else {
+                if (hasDUSDLoans
+                    && arith_uint256(totalCollateralsDFI) * 100 < arith_uint256(collateralsLoans.val->totalLoans) * scheme->ratio / 2
+                    && static_cast<int>(height) >= consensus.FortCanningEpilogueHeight){
+                    return Res::Err("At least 50%% of the minimum required collateral must be in DFI");
+                }
                 if (arith_uint256(totalCollaterals) * 100 < arith_uint256(collateralsLoans.val->totalLoans) * scheme->ratio / 2)
                     return static_cast<int>(height) < consensus.FortCanningRoadHeight ? Res::Err("At least 50%% of the minimum required collateral must be in DFI when taking a loan.")
                                                                                       : Res::Err("At least 50%% of the minimum required collateral must be in DFI or DUSD when taking a loan.");