Updated on 2026-08-14

app/src/main/java/com/tangem/tap/proxy/DerivationManagerImpl.kt

@@ -4,6 +4,8 @@ import com.tangem.blockchain.common.Blockchain
 import com.tangem.blockchain.common.Token
 import com.tangem.common.CompletionResult
 import com.tangem.common.card.EllipticCurve
+import com.tangem.common.core.TangemError
+import com.tangem.common.core.TangemSdkError
 import com.tangem.common.extensions.ByteArrayKey
 import com.tangem.common.extensions.toMapKey
 import com.tangem.common.hdWallet.DerivationPath
@@ -13,6 +15,7 @@ import com.tangem.domain.common.extensions.fromNetworkId
 import com.tangem.lib.crypto.DerivationManager
 import com.tangem.lib.crypto.models.Currency
 import com.tangem.lib.crypto.models.Currency.NonNativeToken
+import com.tangem.lib.crypto.models.errors.UserCancelledException
 import com.tangem.operations.derivation.ExtendedPublicKeysMap
 import com.tangem.tap.DELAY_SDK_DIALOG_CLOSE
 import com.tangem.tap.common.extensions.dispatchDebugErrorNotification
@@ -49,9 +52,10 @@ class DerivationManagerImpl(
             if (scanResponse != null) {
                 deriveMissingBlockchains(
                     scanResponse = scanResponse,
-                    listOf(appCurrency),
+                    currencyList = listOf(appCurrency),
+                    onSuccess = { continuation.resumeWith(Result.success(true)) },
                 ) {
-                    continuation.resumeWith(Result.success(true))
+                    continuation.resumeWith(Result.failure(it))
                 }
             }
         } else {
@@ -84,6 +88,7 @@ class DerivationManagerImpl(
         scanResponse: ScanResponse,
         currencyList: List<com.tangem.tap.features.wallet.models.Currency>,
         onSuccess: (ScanResponse) -> Unit,
+        onFailure: (Exception) -> Unit,
     ) {
         val derivationDataList = listOfNotNull(
             getDerivations(EllipticCurve.Secp256k1, scanResponse, currencyList),
@@ -135,6 +140,7 @@ class DerivationManagerImpl(
                             "Error derivation",
                         ),
                     )
+                    onFailure.invoke(handleTangemError(result.error))
                 }
                 else -> {
                     error("result result is null")
@@ -176,6 +182,19 @@ class DerivationManagerImpl(
         )
     }
 
+    /**
+     * Simple error handler
+     * for now specifically handle only UserCancelled
+     *
+     * @param error [TangemError]
+     */
+    private fun handleTangemError(error: TangemError): Exception {
+        if (error is TangemSdkError.UserCancelled) {
+            return UserCancelledException()
+        }
+        return IllegalStateException(error.customMessage)
+    }
+
     private class DerivationData(
         val derivations: Pair<ByteArrayKey, List<DerivationPath>>,
     )

features/referral/presentation/build.gradle.kts

@@ -12,6 +12,7 @@ dependencies {
     implementation(project(":core:res"))
     implementation(project(":core:utils"))
     implementation(project(":core:ui"))
+    implementation(project(":libs:crypto"))
 
     /** AndroidX */
     implementation(deps.androidx.appCompat)

features/referral/presentation/src/main/java/com/tangem/feature/referral/viewmodels/ReferralViewModel.kt

@@ -15,6 +15,7 @@ import com.tangem.feature.referral.models.ReferralStateHolder
 import com.tangem.feature.referral.models.ReferralStateHolder.ErrorSnackbar
 import com.tangem.feature.referral.models.ReferralStateHolder.ReferralInfoState
 import com.tangem.feature.referral.router.ReferralRouter
+import com.tangem.lib.crypto.models.errors.UserCancelledException
 import com.tangem.utils.coroutines.CoroutineDispatcherProvider
 import com.tangem.utils.coroutines.runCatching
 import dagger.hilt.android.lifecycle.HiltViewModel
@@ -34,6 +35,8 @@ internal class ReferralViewModel @Inject constructor(
 
     private var referralRouter: ReferralRouter by Delegates.notNull()
 
+    private val lastReferralData = mutableStateOf<ReferralData?>(null)
+
     init {
         loadReferralData()
     }
@@ -61,7 +64,11 @@ internal class ReferralViewModel @Inject constructor(
     private fun loadReferralData() {
         uiState = uiState.copy(referralInfoState = ReferralInfoState.Loading)
         viewModelScope.launch(dispatchers.main) {
-            runCatching(dispatchers.io) { referralInteractor.getReferralStatus() }
+            runCatching(dispatchers.io) {
+                referralInteractor.getReferralStatus().apply {
+                    lastReferralData.value = this
+                }
+            }
                 .onSuccess(::showContent)
                 .onFailure(::showErrorSnackbar)
         }
@@ -73,7 +80,16 @@ internal class ReferralViewModel @Inject constructor(
         viewModelScope.launch(dispatchers.main) {
             runCatching(dispatchers.io) { referralInteractor.startReferral() }
                 .onSuccess(::showContent)
-                .onFailure(::showErrorSnackbar)
+                .onFailure {
+                    if (it is UserCancelledException) {
+                        val lastRefData = lastReferralData.value
+                        if (lastRefData != null) {
+                            showContent(lastRefData)
+                        }
+                    } else {
+                        showErrorSnackbar(it)
+                    }
+                }
         }
     }
 

libs/crypto/src/main/java/com/tangem/lib/crypto/models/errors/UserCancelledException.kt

@@ -0,0 +1,3 @@
+package com.tangem.lib.crypto.models.errors
+
+class UserCancelledException : Exception()