fix: add min gas fee to restrict refund action

contracts/jetton_master_chef.tact

@@ -64,14 +64,17 @@ contract JettonMasterChef with Deployable, MasterChef {
                 throw(ERROR_WRONG_AUTH);
             }
             // Calculate the reward jetton for ThunderMint team
-            self.feeForDevs = self.totalReward * FEE_PERCENT_FOR_DEV / 1000; // 0.3% fee
+            let feeForDevs: Int = self.totalReward * FEE_PERCENT_FOR_DEV / 1000; // 0.3% fee
 
             // Have to transfer reward jetton and fee to the contract
-            let expectedAmount: Int = self.totalReward + self.feeForDevs;
+            let expectedAmount: Int = self.totalReward + feeForDevs;
             if(msg.amount < expectedAmount || now() > self.deadline) {
                 self.sendJetton(self.mcRewardJettonWallet, 0 ,msg.amount, msg.sender, msg.sender, SendRemainingValue);
                 return;
             }
+
+            // Set the fee for devs
+            self.feeForDevs = feeForDevs;
             self.isInitialized = true;
 
             // Send Jetton Fee to ThunderMint

contracts/messages.tact

@@ -193,9 +193,10 @@ struct MasterChefData {
 
 // Constants
 const THUNDER_FEE: Int = ton("0.01"); // User have to pay the fee to ThunderMint
-const ACC_PRECISION: Int = pow(10,12);   // Precision for the accumulated reward per share
+const ACC_PRECISION: Int = pow(10, 12);   // Precision for the accumulated reward per share
 const ZERO_ADDRESS: Address = address("0QAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACkT");
 const FEE_PERCENT_FOR_DEV: Int = 3;   // 0.3% of the reward will be given to the ThunderMint
+const MIN_GAS_FEE: Int = ton("0.05"); // Minimum gas fee for calling send ton
 
 // ERROR CODES
 const ERROR_POOL_NOT_FOUND: Int = 1002;

contracts/ton_master_chef.tact

@@ -53,20 +53,23 @@ contract TonMasterChef with Deployable, MasterChef {
             });
             return;
         }
-        let sendedTon: Int = ctx.value;
+        let remainTon: Int = ctx.value - MIN_GAS_FEE;
         let feeForDevs: Int = msg.totalReward * FEE_PERCENT_FOR_DEV / 1000;
-        self.feeForDevs = feeForDevs;
         let expectedTon: Int = msg.totalReward + feeForDevs;
-        if (sendedTon < expectedTon) {
-            self.sendTon(msg.owner, sendedTon - ctx.readForwardFee(), 0);
+        if (remainTon < expectedTon) {
+            self.sendTon(msg.owner, remainTon, 0);
             return;
         }
+        // Update storage when ton is sufficient
         self.isInitialized = true;
-        self.sendTon(self.thunderMintWallet, self.feeForDevs - ctx.readForwardFee(), 0);
-
+        self.feeForDevs = feeForDevs;
+        if (self.feeForDevs > MIN_GAS_FEE) {
+            self.sendTon(self.thunderMintWallet, self.feeForDevs - MIN_GAS_FEE, 0);
+        }
+
         // Sending the remaining TON to the owner
-        if(sendedTon > expectedTon) {
-            self.sendTon(self.owner, sendedTon - expectedTon , 0);
+        if(remainTon > expectedTon) {
+            self.sendTon(self.owner, remainTon - expectedTon, 0);
         }
     }
 

deployments/deployment.json

@@ -1,7 +1,7 @@
 {
   "USDT": "EQBqSpvo4S87mX9tjHaG4zhYZeORhVhMapBJpnMZ64jhrEQK",
   "AirdropFactory": "EQCKrD4mAxJ40TDCuylk2B2bTpCJVslwdE4MEWaMHa6f1x_1",
-  "Kitchen": "EQAF1rmr89SEddR6KQ-7baHDsEg__17xYsMfRO05vUDP_DTN",
+  "Kitchen": "EQDFwPAq7wFQK77xN_Kn0nP1euMobfVlM1ZcxpccW_Inw1CD",
   "MasterChef": "kQBQ80fBfaLY1SgIskc0qTANEO1-aLhvdKcZAL68WWaKlSTO",
   "MerkleDistributor": {
     "seed": "38435217033760998392163658086743783990464893960025036024613934316511459962221",

scripts/buildTonMasterChef.ts

@@ -8,22 +8,22 @@ export async function run(provider: NetworkProvider) {
     const kitchen = provider.open(Kitchen.fromAddress(Address.parse(deployment.Kitchen)));
     const seed = BigInt(`0x${beginCell().storeUint(Date.now(), 64).endCell().hash().toString('hex')}`);
     const masterchefAddress = await kitchen.getGetJettonMasterChefAddress(provider.sender().address!!, seed);
-    const totalReward = 1n * 10n ** 10n;
+    const totalReward = toNano("0.01")
     let sentAmount = (totalReward * 1003n) / 1000n;
     const deadline = BigInt(Math.floor(Date.now() / 1000) + 60 * 60);
-
+    const startTime = BigInt(Math.floor(Date.now() / 1000)) + 10n;
     await kitchen.send(
         provider.sender(),
         {
-            value: sentAmount + toNano('1'),
+            value: sentAmount + toNano('0.1'),
         },
         {
             $$type: 'BuildTonMasterChef',
             owner: provider.sender().address!!,
             seed: seed,
             metaData: beginCell().storeStringTail('httpppp').endCell(),
             deadline: deadline,
-            startTime: BigInt(Math.floor(Date.now() / 1000)) + 10n,
+            startTime: startTime,
             totalReward: totalReward,
         },
     );