IOS-7834 [Staking] Use energy in fee calculation (#831)

tangem · Sep 9, 2024 · aadb2c7 · aadb2c7
1 parent 54b3f74
commit aadb2c7
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Showing 2 changed files with 52 additions and 32 deletions.
diff --git a/BlockchainSdk/Blockchains/Tron/TronNetworkModels.swift b/BlockchainSdk/Blockchains/Tron/TronNetworkModels.swift
@@ -23,6 +23,11 @@ struct TronChainParameters {
     let dynamicEnergyIncreaseFactor: Int
 }
 
+struct TronEnergyFeeData {
+    let energyFee: Int
+    let sunPerEnergyUnit: Int
+}
+
 struct TronAccountInfo {
     let balance: Decimal
     let tokenBalances: [Token: Decimal]
@@ -44,6 +49,12 @@ struct TronGetAccountResponse: Decodable {
 struct TronGetAccountResourceResponse: Decodable {
     let freeNetUsed: Int?
     let freeNetLimit: Int
+    let energyLimit: Decimal
+    let energyUsed: Decimal
+
+    enum CodingKeys: String, CodingKey {
+        case freeNetUsed, freeNetLimit, energyLimit = "EnergyLimit", energyUsed = "EnergyUsed"
+    }
 }
 
 struct TronTransactionInfoRequest: Encodable {

diff --git a/BlockchainSdk/Blockchains/Tron/TronWalletManager.swift b/BlockchainSdk/Blockchains/Tron/TronWalletManager.swift
@@ -72,7 +72,7 @@ class TronWalletManager: BaseManager, WalletManager {
     }
 
     func getFee(amount: Amount, destination: String) -> AnyPublisher<[Fee], Error> {
-        let energyFeePublisher = energyFee(amount: amount, destination: destination)
+        let energyFeePublisher = energyFeeParameters(amount: amount, destination: destination)
 
         let blockchain = wallet.blockchain
 
@@ -95,37 +95,46 @@ class TronWalletManager: BaseManager, WalletManager {
             transactionDataPublisher,
             networkService.getAccountResource(for: wallet.address)
         )
-            .map { energyFee, destinationExists, transactionData, resources -> [Fee] in
-                if !destinationExists && amount.type == .coin {
-                    let amount = Amount(with: blockchain, value: 1.1)
-                    return [Fee(amount)]
-                }
-
-                let sunPerBandwidthPoint = 1000
-
-                let remainingBandwidthInSun = (resources.freeNetLimit - (resources.freeNetUsed ?? 0)) * sunPerBandwidthPoint
-
-                let additionalDataSize = 64
-                let transactionSizeFee = sunPerBandwidthPoint * (transactionData.count + additionalDataSize)
-                let consumedBandwidthFee: Int
-                if transactionSizeFee <= remainingBandwidthInSun {
-                    consumedBandwidthFee = 0
-                } else {
-                    consumedBandwidthFee = transactionSizeFee
-                }
-
-                let totalFee = consumedBandwidthFee + energyFee
-
-                let value = Decimal(totalFee) / blockchain.decimalValue
-                let amount = Amount(with: blockchain, value: value)
+        .map {
+            energyFeeParameters,
+            destinationExists,
+            transactionData,
+            resources -> [Fee] in
+            if !destinationExists && amount.type == .coin {
+                let amount = Amount(with: blockchain, value: 1.1)
                 return [Fee(amount)]
             }
-            .eraseToAnyPublisher()
+
+            let sunPerBandwidthPoint = 1000
+
+            let remainingBandwidth = resources.freeNetLimit - (resources.freeNetUsed ?? 0)
+            let additionalDataSize = 64
+            let transactionSizeFee = transactionData.count + additionalDataSize
+            let consumedBandwidthFee: Int
+            if transactionSizeFee <= remainingBandwidth {
+                consumedBandwidthFee = 0
+            } else {
+                consumedBandwidthFee = transactionSizeFee * sunPerBandwidthPoint
+            }
+
+            let remainingEnergy = resources.energyLimit - resources.energyUsed
+            let consumedEnergyFee = max(
+                .zero,
+                Decimal(energyFeeParameters.energyFee) - remainingEnergy
+            ) * Decimal(energyFeeParameters.sunPerEnergyUnit)
+
+            let totalFee = Decimal(consumedBandwidthFee) + consumedEnergyFee
+
+            let value = totalFee / blockchain.decimalValue
+            let amount = Amount(with: blockchain, value: value)
+            return [Fee(amount)]
+        }
+        .eraseToAnyPublisher()
     }
 
-    private func energyFee(amount: Amount, destination: String) -> AnyPublisher<Int, Error> {
+    private func energyFeeParameters(amount: Amount, destination: String) -> AnyPublisher<TronEnergyFeeData, Error> {
         guard let contractAddress = amount.type.token?.contractAddress else {
-            return .justWithError(output: 0)
+            return .justWithError(output: TronEnergyFeeData(energyFee: 0, sunPerEnergyUnit: 0))
         }
 
         let energyUsagePublisher = Result {
@@ -146,14 +155,14 @@ class TronWalletManager: BaseManager, WalletManager {
                 // Contract's energy fee changes every maintenance period (6 hours) and
                 // since we don't know what period the transaction is going to be executed in
                 // we increase the fee just in case by 20%
-                let sunPerEnergyUnit = chainParameters.sunPerEnergyUnit
-                let energyFee = Double(energyUse * sunPerEnergyUnit)
-
                 let dynamicEnergyIncreaseFactorPresicion = 10_000
                 let dynamicEnergyIncreaseFactor = Double(chainParameters.dynamicEnergyIncreaseFactor) / Double(dynamicEnergyIncreaseFactorPresicion)
-                let conservativeEnergyFee = Int(energyFee * (1 + dynamicEnergyIncreaseFactor))
+                let conservativeEnergyFee = Int(Double(energyUse) * (1 + dynamicEnergyIncreaseFactor))
 
-                return conservativeEnergyFee
+                return TronEnergyFeeData(
+                    energyFee: conservativeEnergyFee,
+                    sunPerEnergyUnit: chainParameters.sunPerEnergyUnit
+                )
             }
             .eraseToAnyPublisher()
     }