Create workbook screen

app/build.gradle

@@ -96,5 +96,7 @@ dependencies {
     implementation "androidx.security:security-crypto:1.0.0"
     // serialization
     implementation "org.jetbrains.kotlinx:kotlinx-serialization-json:1.2.0"
+    // work manager
+    implementation "androidx.work:work-runtime-ktx:2.7.1"
 
 }

app/src/main/java/com/example/examer/data/Repository.kt

@@ -4,10 +4,7 @@ import android.content.Context
 import android.graphics.Bitmap
 import android.net.Uri
 import androidx.core.net.toUri
-import com.example.examer.data.domain.ExamerAudioFile
-import com.example.examer.data.domain.ExamerUser
-import com.example.examer.data.domain.TestDetails
-import com.example.examer.data.domain.WorkBook
+import com.example.examer.data.domain.*
 import com.example.examer.data.dto.AudioFileDTO
 import com.example.examer.data.dto.WorkBookDTO
 import com.example.examer.data.dto.toMultiChoiceQuestion
@@ -27,6 +24,12 @@ interface Repository {
         user: ExamerUser,
         testDetails: TestDetails
     ): Result<List<WorkBook>>
+
+    suspend fun saveUserAnswersForUser(
+        user: ExamerUser,
+        userAnswers: UserAnswers,
+        testDetailId: String
+    )
 }
 
 class ExamerRepository(
@@ -75,6 +78,15 @@ class ExamerRepository(
         Result.failure(exception)
     }
 
+    override suspend fun saveUserAnswersForUser(
+        user: ExamerUser,
+        userAnswers: UserAnswers,
+        testDetailId: String
+    ) {
+        // todo exception handling
+        remoteDatabase.saveUserAnswers(user, userAnswers, testDetailId)
+    }
+
     private fun AudioFileDTO.toExamerAudioFile(localAudioFileUri: Uri) = ExamerAudioFile(
         localAudioFileUri = localAudioFileUri,
         numberOfRepeatsAllowedForAudioFile = numberOfRepeatsAllowedForAudioFile

app/src/main/java/com/example/examer/data/domain/UserAnswers.kt

@@ -0,0 +1,27 @@
+package com.example.examer.data.domain
+
+import com.example.examer.data.dto.UserAnswersDTO
+import kotlinx.serialization.Serializable
+
+@Serializable
+@JvmInline
+value class IndexOfChosenOption(val index: Int) {
+    override fun toString(): String = index.toString()
+}
+
+@Serializable
+data class UserAnswers(
+    val associatedWorkBookId: String,
+    val answers: Map<MultiChoiceQuestion, IndexOfChosenOption>
+)
+
+fun UserAnswers.toUserAnswersDTO() = UserAnswersDTO(
+    associatedWorkBookId = associatedWorkBookId,
+    answersDetailsMap = answers.keys.map {
+        mapOf(
+            "multiChoiceQuestionId" to it.id,
+            "indexOfCorrectOption" to it.indexOfCorrectOption.toString(),
+            "indexOfChosenOption" to answers[it].toString()
+        )
+    }
+)

app/src/main/java/com/example/examer/data/dto/UserAnswersDTO.kt

@@ -0,0 +1,19 @@
+package com.example.examer.data.dto
+
+import com.example.examer.data.domain.UserAnswers
+
+/**
+ * A DTO object for [UserAnswers].
+ * @param associatedWorkBookId the id of the workbook associated
+ * with the [UserAnswers] object.
+ * @param answersDetailsMap a map with custom objects as keys are not
+ * supported. Only strings are supported. Therefore, it is not
+ * possible to use Map<MultiChoiceQuestion, IndexOfChosenOption>
+ * for answers. To accommodate for that, a list of maps are used to
+ * store the details of the each answer. A map in the list consists
+ * of the details of a particular mcq question.
+ */
+data class UserAnswersDTO(
+    val associatedWorkBookId: String,
+    val answersDetailsMap: List<Map<String, String>>
+)

app/src/main/java/com/example/examer/data/remote/FirebaseRemoteDatabase.kt

@@ -5,10 +5,13 @@ import android.net.Uri
 import com.example.examer.data.domain.*
 import com.example.examer.data.dto.AudioFileDTO
 import com.example.examer.data.dto.MultiChoiceQuestionListDTO
+import com.example.examer.data.dto.UserAnswersDTO
 import com.example.examer.data.dto.WorkBookDTO
-import com.example.examer.data.dto.toMultiChoiceQuestion
 import com.example.examer.di.DispatcherProvider
+import com.google.firebase.firestore.CollectionReference
 import com.google.firebase.firestore.DocumentSnapshot
+import com.google.firebase.firestore.Query
+import com.google.firebase.firestore.QuerySnapshot
 import com.google.firebase.firestore.ktx.firestore
 import com.google.firebase.ktx.Firebase
 import com.google.firebase.storage.ktx.storage
@@ -27,7 +30,10 @@ class FirebaseRemoteDatabase(private val dispatcherProvider: DispatcherProvider)
 
     override suspend fun fetchScheduledTestListForUser(user: ExamerUser): List<TestDetails> =
         withContext(dispatcherProvider.io) {
-            val scheduledTestsCollection = fetchCollection(getCollectionPathForScheduledTests(user))
+            val scheduledTestsCollection = fetchCollection(
+                collectionPath = getCollectionPathForTests(user),
+                runOnCollectionReference = { whereEqualTo("testStatus", "scheduled") }
+            )
             // if no collection exists for the user, which likely indicates
             // that the user is a newly registered user, an empty list will
             // be returned.
@@ -36,7 +42,10 @@ class FirebaseRemoteDatabase(private val dispatcherProvider: DispatcherProvider)
 
     override suspend fun fetchPreviousTestListForUser(user: ExamerUser): List<TestDetails> =
         withContext(dispatcherProvider.io) {
-            val previousTestsCollection = fetchCollection(getCollectionPathForPreviousTests(user))
+            val previousTestsCollection = fetchCollection(
+                collectionPath = getCollectionPathForTests(user),
+                runOnCollectionReference = { whereIn("testStatus", listOf("completed", "missed")) }
+            )
             // if no collection exists for the user, which likely indicates
             // that the user is a newly registered user, an empty list will
             // be returned.
@@ -85,6 +94,20 @@ class FirebaseRemoteDatabase(private val dispatcherProvider: DispatcherProvider)
         }
     }
 
+    override suspend fun saveUserAnswers(
+        user: ExamerUser,
+        userAnswers: UserAnswers,
+        testDetailsId: String
+    ) {
+        withContext(dispatcherProvider.io) {
+            Firebase.firestore
+                .collection(getCollectionPathForUserAnswers(user, testDetailsId))
+                .document()
+                .set(userAnswers.toUserAnswersDTO())
+                .await() // throws exception
+        }
+    }
+
     private fun DocumentSnapshot.toWorkBookDTO(): WorkBookDTO {
         val examerAudioFile = AudioFileDTO(
             audioFileUrl = URL(get("audioFileDownloadUrl").toString()),
@@ -119,21 +142,31 @@ class FirebaseRemoteDatabase(private val dispatcherProvider: DispatcherProvider)
             .atZone(ZoneId.systemDefault())
             .toLocalDateTime()
 
-    private suspend fun fetchCollection(collectionPath: String) = Firebase.firestore
+    //TODO add doc
+    private suspend fun fetchCollection(
+        collectionPath: String,
+        runOnCollectionReference: (CollectionReference.() -> Query)? = null
+    ): QuerySnapshot = Firebase
+        .firestore
         .collection(collectionPath)
+        .run {
+            // CollectionReference is a subclass of Query.
+            // if the block is not null, run the block
+            // and return the Query object returned by the block.
+            // if block is null, return the collection reference.
+            runOnCollectionReference?.invoke(this) ?: this
+        }
         .get()
         .await()
 
     companion object {
         private const val PROFILE_PICTURES_FOLDER_NAME = "profile_pics"
-        private fun getCollectionPathForScheduledTests(user: ExamerUser) =
-            "users/${user.id}/scheduledTests"
-
-        private fun getCollectionPathForPreviousTests(user: ExamerUser) =
-            "users/${user.id}/previousTests"
-
+        private fun getCollectionPathForTests(user: ExamerUser) = "users/${user.id}/tests"
         private fun getCollectionPathForWorkBooks(user: ExamerUser, testDetails: TestDetails) =
-            "${getCollectionPathForScheduledTests(user)}/${testDetails.id}/workbooks"
+            "${getCollectionPathForTests(user)}/${testDetails.id}/workbooks"
+
+        private fun getCollectionPathForUserAnswers(user: ExamerUser, testDetailsId: String) =
+            "${getCollectionPathForTests(user)}/${testDetailsId}/answersForEachWorkBook"
     }
 
 }

app/src/main/java/com/example/examer/data/remote/RemoteDatabase.kt

@@ -4,6 +4,7 @@ import android.graphics.Bitmap
 import android.net.Uri
 import com.example.examer.data.domain.ExamerUser
 import com.example.examer.data.domain.TestDetails
+import com.example.examer.data.domain.UserAnswers
 import com.example.examer.data.domain.WorkBook
 import com.example.examer.data.dto.WorkBookDTO
 
@@ -16,4 +17,9 @@ interface RemoteDatabase {
     ): Result<List<WorkBookDTO>>
 
     suspend fun saveBitmap(bitmap: Bitmap, fileName: String): Result<Uri>
+    suspend fun saveUserAnswers(
+        user: ExamerUser,
+        userAnswers: UserAnswers,
+        testDetailsId: String
+    )
 }

app/src/main/java/com/example/examer/data/workers/SaveUserAnswersWorker.kt

@@ -0,0 +1,40 @@
+package com.example.examer.data.workers
+
+import android.content.Context
+import androidx.work.CoroutineWorker
+import androidx.work.WorkerParameters
+import com.example.examer.data.domain.UserAnswers
+import com.example.examer.di.ExamerApplication
+import kotlinx.coroutines.CancellationException
+import kotlinx.serialization.decodeFromString
+import kotlinx.serialization.json.Json
+
+class SaveUserAnswersWorker(
+    private val appContext: Context,
+    workerParameters: WorkerParameters
+) : CoroutineWorker(appContext, workerParameters) {
+    override suspend fun doWork(): Result = try {
+        // deserialize user answers object
+        val userAnswersJsonString = inputData.getString(KEY_USER_ANSWERS_JSON_STRING_ARG)!!
+        val format = Json { allowStructuredMapKeys = true }
+        val userAnswers = format.decodeFromString<UserAnswers>(userAnswersJsonString)
+        // get testDetailsId
+        val testDetailsId = inputData.getString(KEY_TEST_DETAILS_ID_ARG)!!
+        // use the repository to save the UserAnswers object
+        val appContainer = ((appContext) as ExamerApplication).appContainer
+        val currentlyLoggedInUser = appContainer.authenticationService.currentUser.value!!
+        val repository = appContainer.repository
+        repository.saveUserAnswersForUser(currentlyLoggedInUser, userAnswers, testDetailsId)
+        Result.success()
+    } catch (exception: Exception) {
+        if (exception is CancellationException) throw exception
+        Result.failure()
+    }
+
+    companion object {
+        const val KEY_USER_ANSWERS_JSON_STRING_ARG =
+            "com.example.examer.data.workers.SaveUserAnswersWorker.KEY_USER_ANSWERS_ARG"
+        const val KEY_TEST_DETAILS_ID_ARG =
+            "com.example.examer.data.workers.SaveUserAnswersWorker.KEY_TEST_DETAILS_ID_ARG"
+    }
+}

app/src/main/java/com/example/examer/di/AppContainer.kt

@@ -19,7 +19,7 @@ class AppContainer(application: Application) {
         FirebaseRemoteDatabase(StandardDispatchersProvider()) as RemoteDatabase
     private val passwordManager = ExamerPasswordManager(application) as PasswordManager
     val authenticationService = FirebaseAuthenticationService()
-    private val repository = ExamerRepository(
+    val repository = ExamerRepository(
         context = application,
         remoteDatabase = remoteDatabase,
         updateProfilePhotoUriUseCase = UpdateProfilePhotoUriUseCaseImpl(
@@ -51,6 +51,7 @@ class AppContainer(application: Application) {
         testDetailsListType = TestDetailsListType.PREVIOUS_TESTS
     )
 
+    val workBookViewModelFactory = WorkBookViewModelFactory(application = application)
     fun getTestSessionViewModelFactory(
         testDetails: TestDetails,
         workBookList: List<WorkBook>

app/src/main/java/com/example/examer/ui/navigation/TakeTestScreenDestinations.kt

@@ -1,5 +1,27 @@
 package com.example.examer.ui.navigation
 
+import com.example.examer.data.domain.MultiChoiceQuestion
+import com.example.examer.data.domain.WorkBook
+import kotlinx.serialization.encodeToString
+import kotlinx.serialization.json.Json
+import timber.log.Timber
+
 sealed class TakeTestScreenDestinations(val route: String) {
-    object ListenToAudioScreen : TakeTestScreenDestinations("com.example.examer.ui.navigation")
+    object ListenToAudioScreen :
+        TakeTestScreenDestinations("com.example.examer.ui.navigation.WorkBookScreen")
+
+    object WorkBookScreen :
+        TakeTestScreenDestinations("com.example.examer.ui.navigation.WorkBookScreen/{testDetailsId}/{workBookId}/{questionsList}/") {
+        const val WORKBOOK_ID_ARG = "workBookId"
+        const val QUESTIONS_LIST_ARG = "questionsList"
+        const val TEST_DETAILS_ID_ARG = "testDetailsId"
+        fun buildRoute(
+            testDetailsId: String,
+            workBookId: String,
+            multiChoiceQuestionList: List<MultiChoiceQuestion>
+        ): String {
+            val jsonString = Json.encodeToString(multiChoiceQuestionList)
+            return "com.example.examer.ui.navigation.WorkBookScreen/${testDetailsId}/$workBookId/$jsonString/"
+        }
+    }
 }

app/src/main/java/com/example/examer/ui/screens/LoggedInScreen.kt

@@ -190,6 +190,7 @@ fun LoggedInScreen(
 
                 takeTestScreenNavigation(
                     route = ExamerDestinations.TakeTestScreen.route,
+                    navController = loggedInNavController,
                     appContainer = appContainer
                 )
             }