From 9f9d0cd5db151289f1ddf06b092e995aa40e5360 Mon Sep 17 00:00:00 2001
From: Aleksei Muraveinik <amuraveinik@tangem.com>
Date: Wed, 16 Oct 2024 14:40:28 +0200
Subject: [PATCH 1/2] IOS-8253 Use available amount for fee calc

---
 .../Blockchains/Kaspa/KaspaTransactionBuilder.swift  |  5 +++++
 BlockchainSdk/Common/Transaction.swift               | 12 ++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/BlockchainSdk/Blockchains/Kaspa/KaspaTransactionBuilder.swift b/BlockchainSdk/Blockchains/Kaspa/KaspaTransactionBuilder.swift
index 0a26df2a0..72a6ceb57 100644
--- a/BlockchainSdk/Blockchains/Kaspa/KaspaTransactionBuilder.swift
+++ b/BlockchainSdk/Blockchains/Kaspa/KaspaTransactionBuilder.swift
@@ -97,6 +97,11 @@ class KaspaTransactionBuilder {
     }
     
     func buildForMassCalculation(transaction: Transaction) throws -> KaspaTransactionData {
+        let amountValue = min(transaction.amount.value, availableAmount().value)
+        let amount = Amount(with: blockchain, value: amountValue)
+        
+        let transaction = transaction.withAmount(amount)
+        
         let builtTransaction = try buildForSign(transaction).0
         let dummySignature = Data(repeating: 1, count: 65)
         return buildForSend(
diff --git a/BlockchainSdk/Common/Transaction.swift b/BlockchainSdk/Common/Transaction.swift
index ce2d2ebde..80c200c34 100644
--- a/BlockchainSdk/Common/Transaction.swift
+++ b/BlockchainSdk/Common/Transaction.swift
@@ -36,6 +36,18 @@ public struct Transaction {
         self.contractAddress = contractAddress
         self.params = params
     }
+    
+    func withAmount(_ amount: Amount) -> Transaction {
+        Transaction(
+            amount: amount,
+            fee: fee,
+            sourceAddress: sourceAddress,
+            destinationAddress: destinationAddress,
+            changeAddress: changeAddress,
+            contractAddress: contractAddress,
+            params: params
+        )
+    }
 }
 
 extension Transaction: Equatable {

From 9058d55f94823d9bbe3ca7d3230f9e0bd8a8c715 Mon Sep 17 00:00:00 2001
From: Aleksei Muraveinik <amuraveinik@tangem.com>
Date: Wed, 16 Oct 2024 15:40:46 +0200
Subject: [PATCH 2/2] IOS-8253 Change rule for validator

---
 BlockchainSdk/Blockchains/Kaspa/KaspaWalletManager.swift | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/BlockchainSdk/Blockchains/Kaspa/KaspaWalletManager.swift b/BlockchainSdk/Blockchains/Kaspa/KaspaWalletManager.swift
index a33f89ca3..5765dd99f 100644
--- a/BlockchainSdk/Blockchains/Kaspa/KaspaWalletManager.swift
+++ b/BlockchainSdk/Blockchains/Kaspa/KaspaWalletManager.swift
@@ -148,7 +148,13 @@ extension KaspaWalletManager: WithdrawalNotificationProvider {
 
 extension KaspaWalletManager: MaximumAmountRestrictable {
     func validateMaximumAmount(amount: Amount, fee: Amount) throws {
-        let amountAvailableToSend = txBuilder.availableAmount() - fee
+        var amountAvailableToSend = txBuilder.availableAmount() - fee
+
+        let change = amount - amountAvailableToSend
+        if change > .zeroCoin(for: wallet.blockchain), change < dustValue {
+            amountAvailableToSend = amountAvailableToSend - (dustValue - change)
+        }
+        
         if amount <= amountAvailableToSend {
             return
         }