feat: Implement Consumable In-App Purchases

Introduce consumable In-App Purchase (IAP) functionality to overcome the
1000-product limit on the Play Console. This includes:

- Adding a new field, `storeSku`, to store the Play Console product ID. The
  `storeSku` is derived from the combination of the `product_prefix` value
  from Remote Config and `min_price` from course modes in the enrolments API.
- Implementing the process of consuming the product after verifying the
  purchase.

Fixes: LEARNER-9818

Author: HamzaIsrar12

OpenEdXMobile/src/main/java/org/edx/mobile/exception/ErrorMessage.kt

@@ -24,6 +24,7 @@ data class ErrorMessage(
         const val COURSE_REFRESH_CODE = 0x205
         const val PRICE_CODE = 0x206
         const val NO_SKU_CODE = 0x207
+        const val CONSUME_CODE = 0x208
     }
 
     private fun isPreUpgradeErrorType(): Boolean =
@@ -56,6 +57,7 @@ data class ErrorMessage(
     fun canRetry(): Boolean {
         return requestType == PRICE_CODE ||
                 requestType == EXECUTE_ORDER_CODE ||
+                requestType == CONSUME_CODE ||
                 requestType == COURSE_REFRESH_CODE
     }
 }

OpenEdXMobile/src/main/java/org/edx/mobile/extenstion/EncryptionExt.kt

@@ -6,10 +6,22 @@ fun Long.encodeToString(): String {
     return Base64.encodeToString(this.toString().toByteArray(), Base64.DEFAULT)
 }
 
+fun String.encodeToString(): String {
+    return Base64.encodeToString(this.toByteArray(), Base64.DEFAULT)
+}
+
 fun String.decodeToLong(): Long? {
     return try {
         Base64.decode(this, Base64.DEFAULT).toString(Charsets.UTF_8).toLong()
     } catch (ex: Exception) {
         null
     }
 }
+
+fun String.decodeToString(): String? {
+    return try {
+        Base64.decode(this, Base64.DEFAULT).toString(Charsets.UTF_8)
+    } catch (ex: Exception) {
+        null
+    }
+}

OpenEdXMobile/src/main/java/org/edx/mobile/inapppurchases/BillingProcessor.kt

@@ -11,13 +11,15 @@ import com.android.billingclient.api.BillingClientStateListener
 import com.android.billingclient.api.BillingFlowParams
 import com.android.billingclient.api.BillingFlowParams.ProductDetailsParams
 import com.android.billingclient.api.BillingResult
+import com.android.billingclient.api.ConsumeParams
 import com.android.billingclient.api.ProductDetails
 import com.android.billingclient.api.ProductDetailsResult
 import com.android.billingclient.api.Purchase
 import com.android.billingclient.api.PurchasesUpdatedListener
 import com.android.billingclient.api.QueryProductDetailsParams
 import com.android.billingclient.api.QueryPurchasesParams
 import com.android.billingclient.api.acknowledgePurchase
+import com.android.billingclient.api.consumePurchase
 import com.android.billingclient.api.queryProductDetails
 import com.android.billingclient.api.queryPurchasesAsync
 import dagger.hilt.android.qualifiers.ApplicationContext
@@ -26,10 +28,12 @@ import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.suspendCancellableCoroutine
 import kotlinx.coroutines.withContext
+import org.edx.mobile.extenstion.decodeToString
 import org.edx.mobile.extenstion.encodeToString
 import org.edx.mobile.extenstion.resumeIfActive
 import org.edx.mobile.injection.DataSourceDispatcher
 import org.edx.mobile.logger.Logger
+import org.edx.mobile.model.api.EnrolledCoursesResponse.ProductInfo
 import javax.inject.Inject
 import javax.inject.Singleton
 
@@ -125,16 +129,20 @@ class BillingProcessor @Inject constructor(
      * Called to purchase the new product. Query the product details and launch the purchase flow.
      *
      * @param activity active activity to launch our billing flow from
-     * @param productId Product Id to be purchased
      * @param userId    User Id of the purchaser
+     * @param productInfo Course and Product info to purchase
      */
-    suspend fun purchaseItem(activity: Activity, productId: String, userId: Long) {
+    suspend fun purchaseItem(
+        activity: Activity,
+        userId: Long,
+        productInfo: ProductInfo,
+    ) {
         if (isReadyOrConnect()) {
-            val response = querySyncDetails(productId)
+            val response = querySyncDetails(productInfo.storeSku)
             logger.debug("Getting Purchases -> ${response.billingResult}")
 
             response.productDetailsList?.first()?.let {
-                launchBillingFlow(activity, it, userId)
+                launchBillingFlow(activity, it, userId, productInfo.courseSku)
             }
         } else {
             listener.onPurchaseCancel(BillingResponseCode.BILLING_UNAVAILABLE, "")
@@ -152,7 +160,8 @@ class BillingProcessor @Inject constructor(
     private fun launchBillingFlow(
         activity: Activity,
         productDetails: ProductDetails,
-        userId: Long
+        userId: Long,
+        courseSku: String,
     ) {
         val productDetailsParamsList = listOf(
             ProductDetailsParams.newBuilder()
@@ -163,6 +172,7 @@ class BillingProcessor @Inject constructor(
         val billingFlowParams = BillingFlowParams.newBuilder()
             .setProductDetailsParamsList(productDetailsParamsList)
             .setObfuscatedAccountId(userId.encodeToString())
+            .setObfuscatedProfileId(courseSku.encodeToString())
             .build()
 
         billingClient.launchBillingFlow(activity, billingFlowParams)
@@ -235,6 +245,17 @@ class BillingProcessor @Inject constructor(
         ).purchasesList
     }
 
+    suspend fun consumePurchase(purchaseToken: String): BillingResult {
+        isReadyOrConnect()
+        val result = billingClient.consumePurchase(
+            ConsumeParams
+                .newBuilder()
+                .setPurchaseToken(purchaseToken)
+                .build()
+        )
+        return result.billingResult
+    }
+
     companion object {
         private val TAG = BillingProcessor::class.java.simpleName
         private const val RECONNECT_TIMER_START_MILLISECONDS = 1L * 1000L
@@ -251,3 +272,7 @@ class BillingProcessor @Inject constructor(
 
 fun ProductDetails.OneTimePurchaseOfferDetails.getPriceAmount(): Double =
     this.priceAmountMicros.toDouble().div(BillingProcessor.MICROS_TO_UNIT)
+
+fun Purchase.getCourseSku(): String? {
+    return this.accountIdentifiers?.obfuscatedProfileId?.decodeToString()
+}

OpenEdXMobile/src/main/java/org/edx/mobile/model/api/AppConfig.kt

@@ -31,6 +31,9 @@ data class IAPConfig(
     @SerializedName("experiment_enabled")
     val isExperimentEnabled: Boolean = false,
 
+    @SerializedName("android_product_prefix")
+    val productPrefix: String = "",
+
     @SerializedName("android_disabled_versions")
     val disableVersions: List<String> = listOf()
 

OpenEdXMobile/src/main/java/org/edx/mobile/model/api/CourseMode.kt

@@ -2,6 +2,7 @@ package org.edx.mobile.model.api
 
 import com.google.gson.annotations.SerializedName
 import java.io.Serializable
+import kotlin.math.ceil
 
 data class CourseMode(
     @SerializedName("slug")
@@ -12,4 +13,20 @@ data class CourseMode(
 
     @SerializedName("android_sku")
     val androidSku: String?,
-) : Serializable
+
+    @SerializedName("min_price")
+    val price: Double?,
+
+    var storeSku: String?,
+) : Serializable {
+
+    fun setStoreProductSku(storeProductPrefix: String) {
+        val ceilPrice = price
+            ?.let { ceil(it).toInt() }
+            ?.takeIf { it > 0 }
+
+        if (storeProductPrefix.isNotBlank() && ceilPrice != null) {
+            storeSku = "$storeProductPrefix$ceilPrice"
+        }
+    }
+}

OpenEdXMobile/src/main/java/org/edx/mobile/model/api/EnrolledCoursesResponse.kt

@@ -5,6 +5,7 @@ import com.google.gson.annotations.SerializedName
 import org.edx.mobile.interfaces.SectionItemInterface
 import org.edx.mobile.model.course.EnrollmentMode
 import org.edx.mobile.util.DateUtil
+import java.io.Serializable
 import java.util.Date
 
 data class EnrolledCoursesResponse(
@@ -39,11 +40,6 @@ data class EnrolledCoursesResponse(
     val isCertificateEarned: Boolean
         get() = certificateURL.isNullOrEmpty().not()
 
-    val courseSku: String?
-        get() = courseModes?.firstOrNull { item ->
-            EnrollmentMode.VERIFIED.name.equals(item.slug, ignoreCase = true)
-        }?.androidSku.takeUnless { it.isNullOrEmpty() }
-
     val isAuditMode: Boolean
         get() = EnrollmentMode.AUDIT.toString().equals(mode, ignoreCase = true)
 
@@ -59,6 +55,29 @@ data class EnrolledCoursesResponse(
                     EnrollmentMode.VERIFIED.toString().equals(it.slug, ignoreCase = true)
                 } != null
 
+    val productInfo: ProductInfo?
+        get() = courseSku?.let { courseSku ->
+            storeSku?.let { storeSku ->
+                ProductInfo(courseSku, storeSku)
+            }
+        }
+
+    private val courseSku: String?
+        get() = courseModes?.firstOrNull { item ->
+            EnrollmentMode.VERIFIED.name.equals(item.slug, ignoreCase = true)
+        }?.androidSku.takeUnless { it.isNullOrEmpty() }
+
+    private val storeSku: String?
+        get() = courseModes?.firstOrNull { item ->
+            EnrollmentMode.VERIFIED.name.equals(item.slug, ignoreCase = true)
+        }?.storeSku
+
+    fun setStoreSku(storeProductPrefix: String) {
+        courseModes?.forEach {
+            it.setStoreProductSku(storeProductPrefix)
+        }
+    }
+
     override fun isChapter(): Boolean {
         return false
     }
@@ -82,6 +101,11 @@ data class EnrolledCoursesResponse(
     override fun isDownload(): Boolean {
         return false
     }
+
+    data class ProductInfo(
+        val courseSku: String,
+        val storeSku: String,
+    ) : Serializable
 }
 
 /**

OpenEdXMobile/src/main/java/org/edx/mobile/model/api/EnrollmentResponse.kt

@@ -7,6 +7,7 @@ import com.google.gson.JsonElement
 import com.google.gson.JsonObject
 import com.google.gson.annotations.SerializedName
 import com.google.gson.reflect.TypeToken
+import org.edx.mobile.extenstion.isNotNullOrEmpty
 import org.edx.mobile.logger.Logger
 import org.edx.mobile.model.iap.IAPFlowData
 import java.io.Serializable
@@ -59,6 +60,12 @@ data class EnrollmentResponse(
                         AppConfig::class.java
                     )
 
+                    if (appConfig.iapConfig.productPrefix.isNotNullOrEmpty()) {
+                        enrolledCourses.forEach { courseData ->
+                            courseData.setStoreSku(appConfig.iapConfig.productPrefix)
+                        }
+                    }
+
                     EnrollmentResponse(appConfig, enrolledCourses)
                 }
             } catch (ex: Exception) {
@@ -76,12 +83,12 @@ data class EnrollmentResponse(
  */
 fun List<EnrolledCoursesResponse>.getAuditCourses(): List<IAPFlowData> {
     return this.filter {
-        it.isAuditMode && it.courseSku.isNullOrBlank().not()
+        it.isAuditMode && it.productInfo != null
     }.mapNotNull { course ->
-        course.courseSku?.let { sku ->
+        course.productInfo?.let { productInfo ->
             IAPFlowData(
                 courseId = course.courseId,
-                productId = sku,
+                productInfo = productInfo,
                 isCourseSelfPaced = course.course.isSelfPaced
             )
         }

OpenEdXMobile/src/main/java/org/edx/mobile/model/course/CourseComponent.java

@@ -1,5 +1,7 @@
 package org.edx.mobile.model.course;
 
+import static org.edx.mobile.model.api.EnrolledCoursesResponse.ProductInfo;
+
 import android.text.TextUtils;
 
 import androidx.annotation.NonNull;
@@ -43,7 +45,7 @@ public class CourseComponent implements IBlock, IPathNode {
     private String authorizationDenialMessage;
     private AuthorizationDenialReason authorizationDenialReason;
     private SpecialExamInfo specialExamInfo;
-    private String courseSku;
+    private ProductInfo productInfo;
 
     public CourseComponent() {
     }
@@ -69,7 +71,7 @@ public CourseComponent(@NonNull CourseComponent other) {
         this.authorizationDenialMessage = other.authorizationDenialMessage;
         this.authorizationDenialReason = other.authorizationDenialReason;
         this.specialExamInfo = other.specialExamInfo;
-        this.courseSku = other.courseSku;
+        this.productInfo = other.productInfo;
     }
 
     /**
@@ -572,12 +574,12 @@ public SpecialExamInfo getSpecialExamInfo() {
         return specialExamInfo;
     }
 
-    public String getCourseSku() {
-        return courseSku;
+    public ProductInfo getProductInfo() {
+        return productInfo;
     }
 
-    public void setCourseSku(String courseSku) {
-        this.courseSku = courseSku;
+    public void setProductInfo(ProductInfo productInfo) {
+        this.productInfo = productInfo;
     }
 
     public ArrayList<SectionRow> getSectionData() {

OpenEdXMobile/src/main/java/org/edx/mobile/model/iap/IAPFlowData.kt

@@ -1,12 +1,13 @@
 package org.edx.mobile.model.iap
 
+import org.edx.mobile.model.api.EnrolledCoursesResponse.ProductInfo
 import java.io.Serializable
 
 data class IAPFlowData(
     var flowType: IAPFlowType = IAPFlowType.USER_INITIATED,
     var courseId: String = "",
     var isCourseSelfPaced: Boolean = false,
-    var productId: String = "",
+    var productInfo: ProductInfo = ProductInfo("", ""),
     var basketId: Long = 0,
     var purchaseToken: String = "",
     var price: Double = 0.0,
@@ -17,7 +18,7 @@ data class IAPFlowData(
     fun clear() {
         courseId = ""
         isCourseSelfPaced = false
-        productId = ""
+        productInfo = ProductInfo("", "")
         basketId = 0
         price = 0.0
         currencyCode = ""

OpenEdXMobile/src/main/java/org/edx/mobile/util/InAppPurchasesUtils.kt

@@ -4,6 +4,7 @@ import com.android.billingclient.api.Purchase
 import org.edx.mobile.R
 import org.edx.mobile.exception.ErrorMessage
 import org.edx.mobile.http.HttpStatus
+import org.edx.mobile.inapppurchases.getCourseSku
 import org.edx.mobile.model.iap.IAPFlowData
 
 object InAppPurchasesUtils {
@@ -20,7 +21,7 @@ object InAppPurchasesUtils {
     ): MutableList<IAPFlowData> {
         purchases.forEach { purchase ->
             auditCourses.find { course ->
-                purchase.products.first().equals(course.productId)
+                purchase.getCourseSku() == course.productInfo.courseSku
             }?.apply {
                 this.purchaseToken = purchase.purchaseToken
                 this.flowType = flowType