refactor: modify response json

# Conflicts:
#	CMakeLists.txt
#	client/android/src/org/amnezia/vpn/AmneziaActivity.kt

.github/workflows/deploy.yml

@@ -418,13 +418,13 @@ jobs:
         ANDROID_KEYSTORE_KEY_ALIAS: ${{ secrets.ANDROID_RELEASE_KEYSTORE_KEY_ALIAS }}
         ANDROID_KEYSTORE_KEY_PASS: ${{ secrets.ANDROID_RELEASE_KEYSTORE_KEY_PASS }}
       shell: bash
-      run: ./deploy/build_android.sh --aab --apk all --build-platform ${{ env.ANDROID_BUILD_PLATFORM }}
+      run: ./deploy/build_android.sh --aab --play --apk all --build-platform ${{ env.ANDROID_BUILD_PLATFORM }}
 
     - name: 'Upload x86_64 apk'
       uses: actions/upload-artifact@v4
       with:
         name: AmneziaVPN-android-x86_64
-        path: deploy/build/AmneziaVPN-x86_64-release.apk
+        path: deploy/build/AmneziaVPN-oss-x86_64-release.apk
         compression-level: 0
         retention-days: 7
 
@@ -432,7 +432,7 @@ jobs:
       uses: actions/upload-artifact@v4
       with:
         name: AmneziaVPN-android-x86
-        path: deploy/build/AmneziaVPN-x86-release.apk
+        path: deploy/build/AmneziaVPN-oss-x86-release.apk
         compression-level: 0
         retention-days: 7
 
@@ -440,7 +440,7 @@ jobs:
       uses: actions/upload-artifact@v4
       with:
         name: AmneziaVPN-android-arm64-v8a
-        path: deploy/build/AmneziaVPN-arm64-v8a-release.apk
+        path: deploy/build/AmneziaVPN-oss-arm64-v8a-release.apk
         compression-level: 0
         retention-days: 7
 
@@ -448,7 +448,7 @@ jobs:
       uses: actions/upload-artifact@v4
       with:
         name: AmneziaVPN-android-armeabi-v7a
-        path: deploy/build/AmneziaVPN-armeabi-v7a-release.apk
+        path: deploy/build/AmneziaVPN-oss-armeabi-v7a-release.apk
         compression-level: 0
         retention-days: 7
 
@@ -456,7 +456,7 @@ jobs:
       uses: actions/upload-artifact@v4
       with:
         name: AmneziaVPN-android
-        path: deploy/build/AmneziaVPN-release.aab
+        path: deploy/build/AmneziaVPN-play-release.aab
         compression-level: 0
         retention-days: 7
 

client/android/billing/build.gradle.kts

@@ -0,0 +1,19 @@
+plugins {
+    id(libs.plugins.android.library.get().pluginId)
+    id(libs.plugins.kotlin.android.get().pluginId)
+}
+
+kotlin {
+    jvmToolchain(17)
+}
+
+android {
+    namespace = "org.amnezia.vpn.billing"
+}
+
+dependencies {
+    compileOnly(project(":utils"))
+    implementation(libs.androidx.core)
+    implementation(libs.kotlinx.coroutines)
+    implementation(libs.android.billing)
+}

client/android/billing/src/main/kotlin/BillingException.kt

@@ -0,0 +1,65 @@
+import com.android.billingclient.api.BillingClient.BillingResponseCode.BILLING_UNAVAILABLE
+import com.android.billingclient.api.BillingClient.BillingResponseCode.DEVELOPER_ERROR
+import com.android.billingclient.api.BillingClient.BillingResponseCode.ERROR
+import com.android.billingclient.api.BillingClient.BillingResponseCode.FEATURE_NOT_SUPPORTED
+import com.android.billingclient.api.BillingClient.BillingResponseCode.ITEM_ALREADY_OWNED
+import com.android.billingclient.api.BillingClient.BillingResponseCode.ITEM_NOT_OWNED
+import com.android.billingclient.api.BillingClient.BillingResponseCode.ITEM_UNAVAILABLE
+import com.android.billingclient.api.BillingClient.BillingResponseCode.NETWORK_ERROR
+import com.android.billingclient.api.BillingClient.BillingResponseCode.SERVICE_DISCONNECTED
+import com.android.billingclient.api.BillingClient.BillingResponseCode.SERVICE_UNAVAILABLE
+import com.android.billingclient.api.BillingClient.BillingResponseCode.USER_CANCELED
+import com.android.billingclient.api.BillingResult
+import org.amnezia.vpn.util.ErrorCode
+
+internal class BillingException(
+    billingResult: BillingResult,
+    retryable: Boolean = false
+) : Exception(billingResult.toString()) {
+
+    constructor(msg: String) : this(BillingResult.newBuilder()
+        .setResponseCode(DEVELOPER_ERROR)
+        .setDebugMessage(msg)
+        .build())
+
+    val errorCode: Int
+    val isCanceled = billingResult.responseCode == USER_CANCELED
+    val isRetryable = retryable || billingResult.responseCode in setOf(
+        NETWORK_ERROR,
+        SERVICE_DISCONNECTED,
+        SERVICE_UNAVAILABLE,
+        ERROR
+    )
+
+    init {
+        when (billingResult.responseCode) {
+            ERROR -> {
+                errorCode = ErrorCode.BillingGooglePlayError
+            }
+
+            BILLING_UNAVAILABLE, SERVICE_DISCONNECTED, SERVICE_UNAVAILABLE -> {
+                errorCode = ErrorCode.BillingUnavailable
+            }
+
+            DEVELOPER_ERROR, FEATURE_NOT_SUPPORTED, ITEM_NOT_OWNED -> {
+                errorCode = ErrorCode.BillingError
+            }
+
+            ITEM_ALREADY_OWNED -> {
+                errorCode = ErrorCode.SubscriptionAlreadyOwned
+            }
+
+            ITEM_UNAVAILABLE -> {
+                errorCode = ErrorCode.SubscriptionUnavailable
+            }
+
+            NETWORK_ERROR -> {
+                errorCode = ErrorCode.BillingNetworkError
+            }
+
+            else -> {
+                errorCode = ErrorCode.BillingError
+            }
+        }
+    }
+}

client/android/billing/src/main/kotlin/BillingProvider.kt

@@ -0,0 +1,320 @@
+import android.app.Activity
+import android.content.Context
+import com.android.billingclient.api.AcknowledgePurchaseParams
+import com.android.billingclient.api.BillingClient
+import com.android.billingclient.api.BillingClient.BillingResponseCode
+import com.android.billingclient.api.BillingClient.ProductType
+import com.android.billingclient.api.BillingClientStateListener
+import com.android.billingclient.api.BillingFlowParams
+import com.android.billingclient.api.BillingFlowParams.SubscriptionUpdateParams.ReplacementMode
+import com.android.billingclient.api.BillingResult
+import com.android.billingclient.api.GetBillingConfigParams
+import com.android.billingclient.api.PendingPurchasesParams
+import com.android.billingclient.api.ProductDetails
+import com.android.billingclient.api.Purchase
+import com.android.billingclient.api.PurchasesUpdatedListener
+import com.android.billingclient.api.QueryProductDetailsParams
+import com.android.billingclient.api.QueryProductDetailsParams.Product
+import com.android.billingclient.api.QueryPurchasesParams
+import com.android.billingclient.api.acknowledgePurchase
+import com.android.billingclient.api.queryProductDetails
+import com.android.billingclient.api.queryPurchasesAsync
+import kotlinx.coroutines.CancellationException
+import kotlinx.coroutines.CompletableDeferred
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.firstOrNull
+import kotlinx.coroutines.withContext
+import org.amnezia.vpn.util.ErrorCode
+import org.amnezia.vpn.util.Log
+import org.json.JSONArray
+import org.json.JSONObject
+
+private const val TAG = "BillingProvider"
+private const val PRODUCT_ID = "premium"
+
+class BillingProvider(context: Context) : AutoCloseable {
+
+    private var billingClient: BillingClient
+    private var subscriptionPurchases = MutableStateFlow<Pair<BillingResult, List<Purchase>?>?>(null)
+
+    private val purchasesUpdatedListeners = PurchasesUpdatedListener { billingResult, purchases ->
+        Log.v(TAG, "Purchases updated: $billingResult")
+        subscriptionPurchases.value = billingResult to purchases
+    }
+
+    init {
+        billingClient = BillingClient.newBuilder(context)
+            .setListener(purchasesUpdatedListeners)
+            .enablePendingPurchases(PendingPurchasesParams.newBuilder().enableOneTimeProducts().build())
+            .build()
+    }
+
+    private suspend fun connect() {
+        if (billingClient.isReady) return
+
+        Log.v(TAG, "Billing client connection")
+        val connection = CompletableDeferred<Unit>()
+        withContext(Dispatchers.IO) {
+            billingClient.startConnection(object : BillingClientStateListener {
+                override fun onBillingSetupFinished(billingResult: BillingResult) {
+                    Log.v(TAG, "Billing setup finished: $billingResult")
+                    if (billingResult.isOk) {
+                        connection.complete(Unit)
+                    } else {
+                        Log.e(TAG, "Billing setup failed: $billingResult")
+                        connection.completeExceptionally(BillingException(billingResult))
+                    }
+                }
+
+                override fun onBillingServiceDisconnected() {
+                    Log.w(TAG, "Billing service disconnected")
+                }
+            })
+        }
+        connection.await()
+    }
+
+    private suspend fun handleBillingApiCall(block: suspend () -> JSONObject): JSONObject {
+        val numberAttempts = 3
+        var attemptCount = 0
+        while (true) {
+            try {
+                return block()
+            } catch (e: BillingException) {
+                if (e.isCanceled) {
+                    Log.w(TAG, "Billing canceled")
+                    return JSONObject().put("responseCode", ErrorCode.BillingCanceled)
+                } else if (e.isRetryable && attemptCount < numberAttempts) {
+                    Log.d(TAG, "Retryable error: $e")
+                    ++attemptCount
+                    delay(1000)
+                } else {
+                    Log.e(TAG, "Billing error: $e")
+                    return JSONObject().put("responseCode", e.errorCode)
+                }
+            } catch (_: CancellationException) {
+                Log.w(TAG, "Billing coroutine canceled")
+                return JSONObject().put("responseCode", ErrorCode.BillingCanceled)
+            }
+        }
+    }
+
+    suspend fun getSubscriptionPlans(): JSONObject {
+        Log.v(TAG, "Get subscription plans")
+
+        val productDetailsList = getProductDetails()
+        val resultJson = JSONObject().put("responseCode", ErrorCode.NoError)
+        val productArray = JSONArray().also { resultJson.put("products", it) }
+        productDetailsList?.forEach { productDetails ->
+            val product = JSONObject().also { productArray.put(it) }
+                .put("productId", productDetails.productId)
+                .put("name", productDetails.name)
+            val offers = JSONArray().also { product.put("offers", it) }
+            productDetails.subscriptionOfferDetails?.forEach { offerDetails ->
+                val offer = JSONObject().also { offers.put(it) }
+                    .put("basePlanId", offerDetails.basePlanId)
+                    .put("offerId", offerDetails.offerId)
+                    .put("offerToken", offerDetails.offerToken)
+                val pricingPhases = JSONArray().also { offer.put("pricingPhases", it) }
+                offerDetails.pricingPhases.pricingPhaseList.forEach { phase ->
+                    JSONObject().also { pricingPhases.put(it) }
+                        .put("billingCycleCount", phase.billingCycleCount)
+                        .put("billingPeriod", phase.billingPeriod)
+                        .put("formatedPrice", phase.formattedPrice)
+                        .put("recurrenceMode", phase.recurrenceMode)
+                }
+            }
+        }
+        return resultJson
+    }
+
+    private suspend fun getProductDetails(): List<ProductDetails>? {
+        Log.v(TAG, "Get product details")
+
+        val productDetailsParams = Product.newBuilder()
+            .setProductId(PRODUCT_ID)
+            .setProductType(ProductType.SUBS)
+            .build()
+
+        val queryProductDetailsParams = QueryProductDetailsParams.newBuilder()
+            .setProductList(listOf(productDetailsParams))
+            .build()
+
+        val result = withContext(Dispatchers.IO) {
+            billingClient.queryProductDetails(queryProductDetailsParams)
+        }
+
+        Log.v(TAG, "Query product details result: ${result.billingResult}")
+
+        if (!result.billingResult.isOk) {
+            Log.e(TAG, "Failed to get product details: ${result.billingResult}")
+            throw BillingException(result.billingResult)
+        }
+
+        return result.productDetailsList
+    }
+
+    suspend fun getCustomerCountryCode(): JSONObject {
+        Log.v(TAG, "Get customer country code")
+
+        val deferred = CompletableDeferred<String>()
+        withContext(Dispatchers.IO) {
+            billingClient.getBillingConfigAsync(GetBillingConfigParams.newBuilder().build(),
+                { billingResult, billingConfig ->
+                    Log.v(TAG, "Billing config: $billingResult, ${billingConfig?.countryCode}")
+                    if (billingResult.isOk) {
+                        deferred.complete(billingConfig?.countryCode ?: "")
+                    } else {
+                        deferred.completeExceptionally(BillingException(billingResult))
+                    }
+                })
+        }
+        val countryCode = deferred.await()
+
+        return JSONObject()
+            .put("responseCode", ErrorCode.NoError)
+            .put("countryCode", countryCode)
+    }
+
+    suspend fun purchaseSubscription(
+        activity: Activity,
+        offerToken: String,
+        oldPurchaseToken: String? = null
+    ): JSONObject {
+        Log.v(TAG, "Purchase subscription")
+        Log.v(TAG, "Offer token: $offerToken")
+        oldPurchaseToken?.let { Log.v(TAG, "Old purchase token: $it") }
+
+        if (offerToken.isBlank()) throw BillingException("offerToken can not be empty")
+
+        val productDetails = getProductDetails()?.let {
+            it.filter { it.productId == PRODUCT_ID }
+        }?.firstOrNull() ?: throw BillingException("Product details not found")
+
+        Log.v(TAG, "Filtered product details:\n$productDetails")
+
+        val productDetail = BillingFlowParams.ProductDetailsParams.newBuilder()
+            .setProductDetails(productDetails)
+            .setOfferToken(offerToken)
+            .build()
+
+        val subscriptionUpdateParams = oldPurchaseToken?.let {
+            BillingFlowParams.SubscriptionUpdateParams.newBuilder()
+                .setOldPurchaseToken(oldPurchaseToken)
+                .setSubscriptionReplacementMode(ReplacementMode.WITHOUT_PRORATION)
+                .build()
+        }
+
+        val billingResult = billingClient.launchBillingFlow(activity, BillingFlowParams.newBuilder()
+            .setProductDetailsParamsList(listOf(productDetail))
+            .apply { subscriptionUpdateParams?.let { setSubscriptionUpdateParams(it) } }
+            .build())
+
+        Log.v(TAG, "Start billing flow result: $billingResult")
+
+        if (billingResult.responseCode == BillingResponseCode.ITEM_ALREADY_OWNED) {
+            Log.w(TAG, "Attempting to purchase already owned product")
+            val purchases = queryPurchases()
+            if (purchases.any { PRODUCT_ID in it.products }) throw BillingException(billingResult)
+            else throw BillingException(billingResult, retryable = true)
+        } else if (billingResult.responseCode == BillingResponseCode.ITEM_NOT_OWNED) {
+            Log.w(TAG, "Attempting to replace not owned product")
+            val purchases = queryPurchases()
+            if (purchases.all { PRODUCT_ID !in it.products }) throw BillingException(billingResult)
+            else throw BillingException(billingResult, retryable = true)
+        } else if (!billingResult.isOk) throw BillingException(billingResult)
+
+        subscriptionPurchases.firstOrNull { it != null }?.let { (billingResult, purchases) ->
+            if (!billingResult.isOk) throw BillingException(billingResult)
+            return JSONObject()
+                .put("responseCode", ErrorCode.NoError)
+                .put("purchases", processPurchases(purchases))
+        } ?: throw BillingException("Purchase failed")
+    }
+
+    private fun processPurchases(purchases: List<Purchase>?): JSONArray {
+        val purchaseArray = JSONArray()
+        purchases?.forEach { purchase ->
+            /* val purchaseJson = */ JSONObject().also { purchaseArray.put(it) }
+                .put("purchaseToken", purchase.purchaseToken)
+                .put("purchaseTime", purchase.purchaseTime)
+                .put("purchaseState", purchase.purchaseState)
+                .put("isAcknowledged", purchase.isAcknowledged)
+                .put("isAutoRenewing", purchase.isAutoRenewing)
+                .put("orderId", purchase.orderId)
+                // .put("productIds", JSONArray(purchase.products))
+
+            /* purchase.pendingPurchaseUpdate?.let { purchaseUpdate ->
+                JSONObject()
+                    .put("purchaseToken", purchaseUpdate.purchaseToken)
+                    // .put("productIds", JSONArray(purchaseUpdate.products))
+            }.also { purchaseJson.put("pendingPurchaseUpdate", it) } */
+        }
+        return purchaseArray
+    }
+
+    suspend fun acknowledge(purchaseToken: String): JSONObject {
+        Log.v(TAG, "Acknowledge purchase: $purchaseToken")
+
+        val result = withContext(Dispatchers.IO) {
+            billingClient.acknowledgePurchase(
+                AcknowledgePurchaseParams.newBuilder()
+                    .setPurchaseToken(purchaseToken)
+                    .build()
+            )
+        }
+
+        Log.v(TAG, "Acknowledge purchase result: $result")
+
+        if (result.responseCode == BillingResponseCode.ITEM_NOT_OWNED) {
+            Log.w(TAG, "Attempting to acknowledge not owned product")
+            val purchases = queryPurchases()
+            if (purchases.all { PRODUCT_ID !in it.products }) throw BillingException(result)
+            else throw BillingException(result, retryable = true)
+        } else if (!result.isOk && result.responseCode != BillingResponseCode.ITEM_ALREADY_OWNED) {
+            throw BillingException(result)
+        }
+
+        return JSONObject().put("responseCode", ErrorCode.NoError)
+    }
+
+    suspend fun getPurchases(): JSONObject {
+        Log.v(TAG, "Get purchases")
+        val purchases = queryPurchases()
+        return JSONObject()
+            .put("responseCode", ErrorCode.NoError)
+            .put("purchases", processPurchases(purchases))
+    }
+
+    private suspend fun queryPurchases(): List<Purchase> {
+        Log.v(TAG, "Query purchases")
+        val result = withContext(Dispatchers.IO) {
+            billingClient.queryPurchasesAsync(
+                QueryPurchasesParams.newBuilder().setProductType(ProductType.SUBS).build()
+            )
+        }
+        Log.v(TAG, "Query purchases result: ${result.billingResult}")
+        if (!result.billingResult.isOk) throw BillingException(result.billingResult)
+        return result.purchasesList
+    }
+
+    override fun close() {
+        Log.v(TAG, "Close billing client connection")
+        billingClient.endConnection()
+    }
+
+    companion object {
+        suspend fun withBillingProvider(context: Context, block: suspend BillingProvider.() -> JSONObject): String =
+            BillingProvider(context).use { bp ->
+                bp.handleBillingApiCall {
+                    bp.connect()
+                    bp.block()
+                }.toString()
+            }
+    }
+}
+
+internal val BillingResult.isOk: Boolean
+    get() = responseCode == BillingResponseCode.OK

client/android/build.gradle.kts

@@ -20,6 +20,7 @@ android {
     namespace = "org.amnezia.vpn"
 
     buildFeatures {
+        buildConfig = true
         viewBinding = true
     }
 
@@ -41,17 +42,6 @@ android {
         resourceConfigurations += listOf("en", "ru", "b+zh+Hans")
     }
 
-    sourceSets {
-        getByName("main") {
-            manifest.srcFile("AndroidManifest.xml")
-            java.setSrcDirs(listOf("src"))
-            res.setSrcDirs(listOf("res"))
-            // androyddeployqt creates the folders below
-            assets.setSrcDirs(listOf("assets"))
-            jniLibs.setSrcDirs(listOf("libs"))
-        }
-    }
-
     signingConfigs {
         register("release") {
             storeFile = providers.environmentVariable("ANDROID_KEYSTORE_PATH").orNull?.let { file(it) }
@@ -77,6 +67,36 @@ android {
         }
     }
 
+    flavorDimensions += "billing"
+
+    productFlavors {
+        create("oss") {
+            dimension = "billing"
+        }
+        create("play") {
+            dimension = "billing"
+        }
+    }
+
+    sourceSets {
+        getByName("main") {
+            manifest.srcFile("AndroidManifest.xml")
+            java.setSrcDirs(listOf("src"))
+            res.setSrcDirs(listOf("res"))
+            // androyddeployqt creates the folders below
+            assets.setSrcDirs(listOf("assets"))
+            jniLibs.setSrcDirs(listOf("libs"))
+        }
+
+        getByName("oss") {
+            java.setSrcDirs(listOf("oss"))
+        }
+
+        getByName("play") {
+            java.setSrcDirs(listOf("play"))
+        }
+    }
+
     splits {
         abi {
             isEnable = true
@@ -122,4 +142,9 @@ dependencies {
     implementation(libs.google.mlkit)
     implementation(libs.androidx.datastore)
     implementation(libs.androidx.biometric)
+
+    playImplementation(project(":billing"))
 }
+
+fun DependencyHandler.playImplementation(dependency: Any): Dependency? =
+    add("playImplementation", dependency)

client/android/gradle/libs.versions.toml

@@ -1,6 +1,7 @@
 [versions]
 agp = "8.5.2"
 kotlin = "1.9.24"
+android-billing = "7.0.0"
 androidx-core = "1.13.1"
 androidx-activity = "1.9.1"
 androidx-annotation = "1.8.2"
@@ -14,6 +15,7 @@ kotlinx-serialization = "1.6.3"
 google-mlkit = "17.3.0"
 
 [libraries]
+android-billing = { module = "com.android.billingclient:billing-ktx", version.ref = "android-billing" }
 androidx-core = { module = "androidx.core:core-ktx", version.ref = "androidx-core" }
 androidx-activity = { module = "androidx.activity:activity-ktx", version.ref = "androidx-activity" }
 androidx-annotation = { module = "androidx.annotation:annotation", version.ref = "androidx-annotation" }

client/android/oss/org/amnezia/vpn/BillingPaymentRepository.kt

@@ -0,0 +1,13 @@
+package org.amnezia.vpn
+
+import android.app.Activity
+import android.content.Context
+
+class BillingPaymentRepository(@Suppress("UNUSED_PARAMETER") context: Context) : BillingRepository {
+    override suspend fun getCountryCode(): String = ""
+    override suspend fun getSubscriptionPlans(): String = ""
+    override suspend fun purchaseSubscription(activity: Activity, offerToken: String): String = ""
+    override suspend fun upgradeSubscription(activity: Activity, offerToken: String, oldPurchaseToken: String): String = ""
+    override suspend fun acknowledge(purchaseToken: String): String = ""
+    override suspend fun queryPurchases(): String = ""
+}

client/android/play/org/amnezia/vpn/BillingPaymentRepository.kt

@@ -0,0 +1,34 @@
+package org.amnezia.vpn
+
+import android.app.Activity
+import android.content.Context
+import BillingProvider.Companion.withBillingProvider
+
+class BillingPaymentRepository(private val context: Context) : BillingRepository {
+
+    override suspend fun getCountryCode(): String = withBillingProvider(context) {
+        getCustomerCountryCode()
+    }
+
+    override suspend fun getSubscriptionPlans(): String = withBillingProvider(context) {
+        getSubscriptionPlans()
+    }
+
+    override suspend fun purchaseSubscription(activity: Activity, offerToken: String): String =
+        withBillingProvider(context) {
+            purchaseSubscription(activity, offerToken)
+    }
+
+    override suspend fun upgradeSubscription(activity: Activity, offerToken: String, oldPurchaseToken: String): String =
+        withBillingProvider(context) {
+            purchaseSubscription(activity, offerToken, oldPurchaseToken)
+        }
+
+    override suspend fun acknowledge(purchaseToken: String): String = withBillingProvider(context) {
+        acknowledge(purchaseToken)
+    }
+
+    override suspend fun queryPurchases(): String = withBillingProvider(context) {
+        getPurchases()
+    }
+}

client/android/settings.gradle.kts

@@ -31,6 +31,7 @@ rootProject.buildFileName = "build.gradle.kts"
 
 include(":qt")
 include(":utils")
+include(":billing")
 include(":protocolApi")
 include(":wireguard")
 include(":awg")

client/android/src/org/amnezia/vpn/AmneziaActivity.kt

@@ -30,6 +30,7 @@ import androidx.annotation.RequiresApi
 import androidx.core.content.ContextCompat
 import java.io.IOException
 import kotlin.LazyThreadSafetyMode.NONE
+import kotlin.coroutines.CoroutineContext
 import kotlin.text.RegexOption.IGNORE_CASE
 import AppListProvider
 import kotlinx.coroutines.CompletableDeferred
@@ -40,7 +41,6 @@ import kotlinx.coroutines.async
 import kotlinx.coroutines.cancel
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.runBlocking
-import kotlinx.coroutines.withContext
 import org.amnezia.vpn.protocol.getStatistics
 import org.amnezia.vpn.protocol.getStatus
 import org.amnezia.vpn.qt.QtAndroidController
@@ -71,6 +71,7 @@ class AmneziaActivity : QtActivity() {
     private var isInBoundState = false
     private var notificationStateReceiver: BroadcastReceiver? = null
     private lateinit var vpnServiceMessenger: IpcMessenger
+    private lateinit var billingRepository: BillingRepository
 
     private val actionResultHandlers = mutableMapOf<Int, ActivityResultHandler>()
     private val permissionRequestHandlers = mutableMapOf<Int, PermissionRequestHandler>()
@@ -180,6 +181,7 @@ class AmneziaActivity : QtActivity() {
         registerBroadcastReceivers()
         intent?.let(::processIntent)
         runBlocking { vpnProto = proto.await() }
+        billingRepository = BillingPaymentRepository(applicationContext)
     }
 
     private fun loadLibs() {
@@ -647,15 +649,9 @@ class AmneziaActivity : QtActivity() {
     @Suppress("unused")
     fun getAppList(): String {
         Log.v(TAG, "Get app list")
-        var appList = ""
-        runBlocking {
-            mainScope.launch {
-                withContext(Dispatchers.IO) {
-                    appList = AppListProvider.getAppList(packageManager, packageName)
-                }
-            }.join()
+        return blockingCall(Dispatchers.IO) {
+            AppListProvider.getAppList(packageManager, packageName)
         }
-        return appList
     }
 
     @Suppress("unused")
@@ -721,6 +717,47 @@ class AmneziaActivity : QtActivity() {
         }
     }
 
+    @Suppress("unused")
+    fun isPlay(): Boolean = BuildConfig.FLAVOR == "play"
+
+    @Suppress("unused")
+    fun getCountryCode(): String {
+        Log.v(TAG, "Get country code")
+        return blockingCall { billingRepository.getCountryCode() }
+    }
+
+    @Suppress("unused")
+    fun getSubscriptionPlans(): String {
+        Log.v(TAG, "Get subscription plans")
+        return blockingCall { billingRepository.getSubscriptionPlans() }
+    }
+
+    @Suppress("unused")
+    fun purchaseSubscription(offerToken: String): String {
+        Log.v(TAG, "Purchase subscription")
+        return blockingCall { billingRepository.purchaseSubscription(this@AmneziaActivity, offerToken) }
+    }
+
+    @Suppress("unused")
+    fun upgradeSubscription(offerToken: String, oldPurchaseToken: String): String {
+        Log.v(TAG, "Upgrade subscription")
+        return blockingCall {
+            billingRepository.upgradeSubscription(this@AmneziaActivity, offerToken, oldPurchaseToken)
+        }
+    }
+
+    @Suppress("unused")
+    fun acknowledgePurchase(purchaseToken: String): String {
+        Log.v(TAG, "Acknowledge purchase")
+        return blockingCall { billingRepository.acknowledge(purchaseToken) }
+    }
+
+    @Suppress("unused")
+    fun queryPurchases(): String {
+        Log.v(TAG, "Query purchases")
+        return blockingCall { billingRepository.queryPurchases() }
+    }
+
     // workaround for a bug in Qt that causes the mouse click event not to be handled
     // also disable right-click, as it causes the application to crash
     private var lastButtonState = 0
@@ -784,6 +821,13 @@ class AmneziaActivity : QtActivity() {
     /**
      * Utils methods
      */
+    private fun <T> blockingCall(
+        context: CoroutineContext = Dispatchers.Default,
+        block: suspend () -> T
+    ) = runBlocking {
+        mainScope.async(context) { block() }.await()
+    }
+
     companion object {
         private fun actionCodeToString(actionCode: Int): String =
             when (actionCode) {

client/android/src/org/amnezia/vpn/AmneziaApplication.kt

@@ -1,5 +1,6 @@
 package org.amnezia.vpn
 
+import android.system.Os
 import androidx.camera.camera2.Camera2Config
 import androidx.camera.core.CameraSelector
 import androidx.camera.core.CameraXConfig
@@ -12,6 +13,9 @@ private const val TAG = "AmneziaApplication"
 class AmneziaApplication : QtApplication(), CameraXConfig.Provider {
 
     override fun onCreate() {
+        if (BuildConfig.DEBUG) {
+            Os.setenv("QT_ANDROID_DEBUGGER_MAIN_THREAD_SLEEP_MS", "0", true)
+        }
         super.onCreate()
         Prefs.init(this)
         Log.init(this)

client/android/src/org/amnezia/vpn/BillingRepository.kt

@@ -0,0 +1,12 @@
+package org.amnezia.vpn
+
+import android.app.Activity
+
+interface BillingRepository {
+    suspend fun getCountryCode(): String
+    suspend fun getSubscriptionPlans(): String
+    suspend fun purchaseSubscription(activity: Activity, offerToken: String): String
+    suspend fun upgradeSubscription(activity: Activity, offerToken: String, oldPurchaseToken: String): String
+    suspend fun acknowledge(purchaseToken: String): String
+    suspend fun queryPurchases(): String
+}

client/android/utils/src/main/kotlin/ErrorCode.kt

@@ -0,0 +1,14 @@
+package org.amnezia.vpn.util
+
+// keep synchronized with client/core/defs.h error_code_ns::ErrorCode
+object ErrorCode {
+    const val NoError = 0
+
+    const val BillingCanceled = 1300
+    const val BillingError = 1301
+    const val BillingGooglePlayError = 1302
+    const val BillingUnavailable = 1303
+    const val SubscriptionAlreadyOwned = 1304
+    const val SubscriptionUnavailable = 1305
+    const val BillingNetworkError = 1306
+}

client/core/defs.h

@@ -116,7 +116,16 @@ namespace amnezia
         PermissionsError = 1202,
         UnspecifiedError = 1203,
         FatalError = 1204,
-        AbortError = 1205
+        AbortError = 1205,
+
+        // Billing errors
+        BillingCanceled = 1300,
+        BillingError = 1301,
+        BillingGooglePlayError = 1302,
+        BillingUnavailable = 1303,
+        SubscriptionAlreadyOwned = 1304,
+        SubscriptionUnavailable = 1305,
+        BillingNetworkError = 1306,
       };
       Q_ENUM_NS(ErrorCode)
     }

client/core/errorstrings.cpp

@@ -72,6 +72,15 @@ QString errorString(ErrorCode code) {
     case(ErrorCode::FatalError): errorMessage =  QObject::tr("QFile error: A fatal error occurred"); break;
     case(ErrorCode::AbortError): errorMessage =  QObject::tr("QFile error: The operation was aborted"); break;
 
+    // Billing errors
+    case(ErrorCode::BillingCanceled): errorMessage = QObject::tr("Transaction was canceled by the user"); break;
+    case(ErrorCode::BillingError): errorMessage = QObject::tr("Billing error"); break;
+    case(ErrorCode::BillingGooglePlayError): errorMessage = QObject::tr("Internal Google Play error, please try again later"); break;
+    case(ErrorCode::BillingUnavailable): errorMessage = QObject::tr("Billing is unavailable, please try again later"); break;
+    case(ErrorCode::SubscriptionAlreadyOwned): errorMessage = QObject::tr("You already own this subscription"); break;
+    case(ErrorCode::SubscriptionUnavailable): errorMessage = QObject::tr("The requested subscription is not available for purchase"); break;
+    case(ErrorCode::BillingNetworkError): errorMessage = QObject::tr("A network error occurred during the operation, please check the Internet connection"); break;
+
     case(ErrorCode::InternalError):
     default:
         errorMessage = QObject::tr("Internal error"); break;

client/platforms/android/android_controller.cpp

@@ -287,6 +287,51 @@ bool AndroidController::requestAuthentication()
     return result;
 }
 
+bool AndroidController::isPlay()
+{
+    return callActivityMethod<jboolean>("isPlay", "()Z");
+}
+
+QJsonObject AndroidController::getSubscriptionPlans()
+{
+    QJniObject subscriptionPlans = callActivityMethod<jstring>("getSubscriptionPlans", "()Ljava/lang/String;");
+    QJsonObject json = QJsonDocument::fromJson(subscriptionPlans.toString().toUtf8()).object();
+    return json;
+}
+
+QJsonObject AndroidController::purchaseSubscription(const QString &offerToken)
+{
+    QJniObject result = callActivityMethod<jstring, jstring>("purchaseSubscription", "(Ljava/lang/String;)Ljava/lang/String;",
+                                                    QJniObject::fromString(offerToken).object<jstring>());
+    QJsonObject json = QJsonDocument::fromJson(result.toString().toUtf8()).object();
+    return json;
+}
+
+QJsonObject AndroidController::upgradeSubscription(const QString &offerToken, const QString &oldPurchaseToken)
+{
+    QJniObject result = callActivityMethod<jstring, jstring, jstring>("upgradeSubscription",
+                                                                      "(Ljava/lang/String;Ljava/lang/String;)Ljava/lang/String;",
+                                                                      QJniObject::fromString(offerToken).object<jstring>(),
+                                                                      QJniObject::fromString(oldPurchaseToken).object<jstring>());
+    QJsonObject json = QJsonDocument::fromJson(result.toString().toUtf8()).object();
+    return json;
+}
+
+QJsonObject AndroidController::acknowledgePurchase(const QString &purchaseToken)
+{
+    QJniObject result = callActivityMethod<jstring, jstring>("acknowledgePurchase", "(Ljava/lang/String;)Ljava/lang/String;",
+                                                             QJniObject::fromString(purchaseToken).object<jstring>());
+    QJsonObject json = QJsonDocument::fromJson(result.toString().toUtf8()).object();
+    return json;
+}
+
+QJsonObject AndroidController::queryPurchases()
+{
+    QJniObject result = callActivityMethod<jstring>("queryPurchases", "()Ljava/lang/String;");
+    QJsonObject json = QJsonDocument::fromJson(result.toString().toUtf8()).object();
+    return json;
+}
+
 // Moving log processing to the Android side
 jclass AndroidController::log;
 jmethodID AndroidController::logDebug;

client/platforms/android/android_controller.h

@@ -48,6 +48,12 @@ public:
     bool isNotificationPermissionGranted();
     void requestNotificationPermission();
     bool requestAuthentication();
+    bool isPlay();
+    QJsonObject getSubscriptionPlans();
+    QJsonObject purchaseSubscription(const QString &offerToken);
+    QJsonObject upgradeSubscription(const QString &offerToken, const QString &oldPurchaseToken);
+    QJsonObject acknowledgePurchase(const QString &purchaseToken);
+    QJsonObject queryPurchases();
 
     static bool initLogging();
     static void messageHandler(QtMsgType type, const QMessageLogContext &context, const QString &message);

deploy/build_android.sh

@@ -23,6 +23,7 @@ Options:
                                   By default, the latest available platform is used
  -m, --move                       Move the build result to the root of the build directory
  -f, --fdroid                     Build for F-Droid
+ -p, --play                       Build AAB for Google Play
  -h, --help                       Display this help
 
 EOT
@@ -30,7 +31,7 @@ EOT
 
 BUILD_TYPE="release"
 
-opts=$(getopt -l debug,aab,apk:,build-platform:,move,fdroid,help -o "dua:b:mfh" -- "$@")
+opts=$(getopt -l debug,aab,apk:,build-platform:,move,fdroid,play,help -o "dua:b:mfph" -- "$@")
 eval set -- "$opts"
 while true; do
   case "$1" in
@@ -40,6 +41,7 @@ while true; do
     -b | --build-platform) ANDROID_BUILD_PLATFORM=$2; shift 2;;
     -m | --move) MOVE_RESULT=1; shift;;
     -f | --fdroid) FDROID=1; shift;;
+    -p | --play) PLAY=1; shift;;
     -h | --help) usage; exit 0;;
     --) shift; break;;
   esac
@@ -149,11 +151,17 @@ if [ -v FDROID ]; then
   BUILD_TYPE="fdroid"
 fi
 
+if [ -v PLAY ]; then
+  AAB_FLAVOR="play"
+else
+  AAB_FLAVOR="oss"
+fi
+
 if [ -v AAB ]; then
-  gradle_opts+=(bundle"${BUILD_TYPE^}")
+  gradle_opts+=(bundle"${AAB_FLAVOR^}${BUILD_TYPE^}")
 fi
 if [ -v ABIS ]; then
-  gradle_opts+=(assemble"${BUILD_TYPE^}")
+  gradle_opts+=(assembleOss"${BUILD_TYPE^}")
 fi
 
 $OUT_APP_DIR/android-build/gradlew \
@@ -164,7 +172,7 @@ $OUT_APP_DIR/android-build/gradlew \
 if [[ -v CI || -v MOVE_RESULT ]]; then
   echo "Moving APK/AAB..."
   if [ -v AAB ]; then
-    mv -u $OUT_APP_DIR/android-build/build/outputs/bundle/$BUILD_TYPE/AmneziaVPN-$BUILD_TYPE.aab \
+    mv -u $OUT_APP_DIR/android-build/build/outputs/bundle/$AAB_FLAVOR"${BUILD_TYPE^}"/AmneziaVPN-$AAB_FLAVOR-$BUILD_TYPE.aab \
        $PROJECT_DIR/deploy/build/
   fi
 
@@ -181,7 +189,7 @@ if [[ -v CI || -v MOVE_RESULT ]]; then
     IFS=';' read -r -a abi_array <<< "$ABIS"
     for ABI in "${abi_array[@]}"
     do
-      mv -u $OUT_APP_DIR/android-build/build/outputs/apk/$BUILD_TYPE/AmneziaVPN-$ABI-$suffix.apk \
+      mv -u $OUT_APP_DIR/android-build/build/outputs/apk/oss/$BUILD_TYPE/AmneziaVPN-oss-$ABI-$suffix.apk \
        $PROJECT_DIR/deploy/build/
     done
   fi