Updated on 2026-08-14

core/datasource/src/main/java/com/tangem/datasource/di/exchangeservice/ExchangeServiceLoaderModule.kt

@@ -0,0 +1,18 @@
+package com.tangem.datasource.di.exchangeservice
+
+import com.tangem.datasource.exchangeservice.swap.DefaultSwapServiceLoader
+import com.tangem.datasource.exchangeservice.swap.SwapServiceLoader
+import dagger.Binds
+import dagger.Module
+import dagger.hilt.InstallIn
+import dagger.hilt.components.SingletonComponent
+import javax.inject.Singleton
+
+@Module
+@InstallIn(SingletonComponent::class)
+internal interface ExchangeServiceLoaderModule {
+
+    @Binds
+    @Singleton
+    fun bindSwapServiceLoader(defaultSwapServiceLoader: DefaultSwapServiceLoader): SwapServiceLoader
+}

core/datasource/src/main/java/com/tangem/datasource/exchangeservice/swap/DefaultSwapServiceLoader.kt

@@ -0,0 +1,76 @@
+package com.tangem.datasource.exchangeservice.swap
+
+import com.tangem.datasource.api.common.response.getOrThrow
+import com.tangem.datasource.api.express.TangemExpressApi
+import com.tangem.datasource.api.express.models.TangemExpressValues.EMPTY_CONTRACT_ADDRESS_VALUE
+import com.tangem.datasource.api.express.models.request.AssetsRequestBody
+import com.tangem.datasource.api.express.models.request.LeastTokenInfo
+import com.tangem.datasource.api.express.models.response.Asset
+import com.tangem.datasource.api.tangemTech.models.UserTokensResponse
+import com.tangem.datasource.local.token.ExpressAssetsStore
+import com.tangem.domain.core.lce.Lce
+import com.tangem.domain.core.utils.lceContent
+import com.tangem.domain.core.utils.lceError
+import com.tangem.domain.core.utils.lceLoading
+import com.tangem.domain.wallets.models.UserWalletId
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.update
+import timber.log.Timber
+import javax.inject.Inject
+
+typealias InitializationStatusFlow = MutableStateFlow<Lce<Throwable, List<Asset>>>
+
+/**
+ * Default implementation of [SwapServiceLoader]
+ *
+ * @property tangemExpressApi   express api
+ * @property expressAssetsStore local storage
+ *
+[REDACTED_AUTHOR]
+ */
+internal class DefaultSwapServiceLoader @Inject constructor(
+    private val tangemExpressApi: TangemExpressApi,
+    private val expressAssetsStore: ExpressAssetsStore,
+) : SwapServiceLoader {
+
+    private val initializationStatuses: Map<UserWalletId, InitializationStatusFlow> = mapOf()
+
+    override suspend fun update(userWalletId: UserWalletId, userTokens: UserTokensResponse) {
+        val initializationStatus = getInitializationStatusInternal(userWalletId)
+
+        initializationStatus.update { lceLoading() }
+
+        try {
+            val tokensList = userTokens.tokens.map {
+                LeastTokenInfo(
+                    contractAddress = it.contractAddress ?: EMPTY_CONTRACT_ADDRESS_VALUE,
+                    network = it.networkId,
+                )
+            }
+
+            if (tokensList.isNotEmpty()) {
+                val response = tangemExpressApi.getAssets(
+                    body = AssetsRequestBody(tokensList = tokensList),
+                ).getOrThrow()
+
+                expressAssetsStore.store(userWalletId, response)
+
+                initializationStatus.update { response.lceContent() }
+            }
+        } catch (e: Throwable) {
+            initializationStatus.update { e.lceError() }
+            Timber.e(e, "Unable to fetch assets for: ${userWalletId.stringValue}")
+        }
+    }
+
+    override fun getInitializationStatus(userWalletId: UserWalletId): InitializationStatusFlow {
+        return getInitializationStatusInternal(userWalletId)
+    }
+
+    private fun getInitializationStatusInternal(userWalletId: UserWalletId): InitializationStatusFlow {
+        return initializationStatuses.getOrDefault(
+            key = userWalletId,
+            defaultValue = MutableStateFlow(value = lceLoading()),
+        )
+    }
+}

core/datasource/src/main/java/com/tangem/datasource/exchangeservice/swap/SwapServiceLoader.kt

@@ -0,0 +1,21 @@
+package com.tangem.datasource.exchangeservice.swap
+
+import com.tangem.datasource.api.express.models.response.Asset
+import com.tangem.datasource.api.tangemTech.models.UserTokensResponse
+import com.tangem.domain.core.lce.Lce
+import com.tangem.domain.wallets.models.UserWalletId
+import kotlinx.coroutines.flow.StateFlow
+
+/**
+ * Swap service loader
+ *
+[REDACTED_AUTHOR]
+ */
+interface SwapServiceLoader {
+
+    /** Update service using [userWalletId] and [userTokens] */
+    suspend fun update(userWalletId: UserWalletId, userTokens: UserTokensResponse)
+
+    /** Get initialization status by [userWalletId] */
+    fun getInitializationStatus(userWalletId: UserWalletId): StateFlow<Lce<Throwable, List<Asset>>>
+}