Refactor AuthRepository by creating authState

Resolves #23

app/src/main/java/io/foundy/camstudy/MainViewModel.kt

@@ -4,41 +4,33 @@ import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import com.ramcosta.composedestinations.spec.DirectionDestinationSpec
 import dagger.hilt.android.lifecycle.HiltViewModel
-import io.foundy.auth.domain.usecase.ExistsInitInfoUseCase
-import io.foundy.auth.domain.usecase.GetCurrentUserIdUseCase
+import io.foundy.auth.domain.model.AuthState
+import io.foundy.auth.domain.usecase.GetAuthStateStreamUseCase
 import io.foundy.auth.ui.destinations.LoginRouteDestination
 import io.foundy.home.ui.destinations.HomeRouteDestination
 import io.foundy.welcome.ui.destinations.WelcomeRouteDestination
+import kotlinx.coroutines.flow.firstOrNull
 import kotlinx.coroutines.launch
 import javax.inject.Inject
 
 @HiltViewModel
 class MainViewModel @Inject constructor(
-    private val getCurrentUserIdUseCase: GetCurrentUserIdUseCase,
-    private val existsInitInfoUseCase: ExistsInitInfoUseCase
+    private val getAuthStateStreamUseCase: GetAuthStateStreamUseCase,
 ) : ViewModel() {
 
     private var _startDestination: DirectionDestinationSpec? = null
     val startDestination: DirectionDestinationSpec? get() = _startDestination
 
     init {
         viewModelScope.launch {
-            val currentUserId = getCurrentUserIdUseCase()
-            if (currentUserId == null) {
-                _startDestination = LoginRouteDestination
-            } else {
-                val existsInitInfo = existsInitInfoUseCase()
-                if (existsInitInfo == null) {
-                    // 로그인이 되어 있으나 초기 정보 입력 여부를 판단할 수 없는 경우 서버와의 연결에 실패한 것이다.
-                    // 에러 메시지는 로그인 화면에서 보이기 때문에 따로 여기서 에러 메시지를 보이는 로직은 없다.
-                    _startDestination = LoginRouteDestination
-                    return@launch
-                }
-                _startDestination = if (existsInitInfo) {
+            _startDestination = when (val authState = getAuthStateStreamUseCase().firstOrNull()) {
+                is AuthState.SignedIn -> if (authState.existsInitInfo) {
                     HomeRouteDestination
                 } else {
                     WelcomeRouteDestination
                 }
+
+                else -> LoginRouteDestination
             }
         }
     }

app/src/test/java/io/foundy/camstudy/MainViewModelTest.kt

@@ -1,8 +1,8 @@
 package io.foundy.camstudy
 
 import dagger.hilt.android.testing.HiltAndroidTest
-import io.foundy.auth.domain.usecase.ExistsInitInfoUseCase
-import io.foundy.auth.domain.usecase.GetCurrentUserIdUseCase
+import io.foundy.auth.domain.model.AuthState
+import io.foundy.auth.domain.usecase.GetAuthStateStreamUseCase
 import io.foundy.auth.ui.destinations.LoginRouteDestination
 import io.foundy.camstudy.fake.FakeAuthRepository
 import io.foundy.core.test.MainDispatcherRule
@@ -29,46 +29,47 @@ class MainViewModelTest {
     private lateinit var viewModel: MainViewModel
 
     @Test
-    fun `should startDestination is Login when currentUserId is null`() = runTest {
+    fun `should startDestination is Login when not signed in`() = runTest {
         initViewModel()
-        authRepository.currentUserIdSharedFlow.emit(null)
+        authRepository.emitState(AuthState.NotSignedIn)
 
         assertEquals(LoginRouteDestination, viewModel.startDestination)
     }
 
     @Test
     fun `should startDestination is Home when currentUserId and init info exist`() = runTest {
-        authRepository.currentUserIdSharedFlow.emit("id")
-        authRepository.existsInitInfoTestValue = true
         initViewModel()
+        authRepository.emitState(AuthState.SignedIn(currentUserId = "id", existsInitInfo = true))
 
         assertEquals(HomeRouteDestination, viewModel.startDestination)
     }
 
     @Test
     fun `should startDestination is Welcome when currentUserId exists but init info not`() =
         runTest {
-            authRepository.currentUserIdSharedFlow.emit("id")
-            authRepository.existsInitInfoTestValue = false
             initViewModel()
+            authRepository.emitState(
+                AuthState.SignedIn(
+                    currentUserId = "id",
+                    existsInitInfo = false
+                )
+            )
 
             assertEquals(WelcomeRouteDestination, viewModel.startDestination)
         }
 
     @Test
-    fun `should startDestination is Login when currentUserId exists but init info is null`() =
+    fun `should startDestination is Login when there is error`() =
         runTest {
-            authRepository.currentUserIdSharedFlow.emit("id")
-            authRepository.existsInitInfoTestValue = null
             initViewModel()
+            authRepository.emitState(AuthState.Error)
 
             assertEquals(LoginRouteDestination, viewModel.startDestination)
         }
 
     private fun initViewModel() {
         viewModel = MainViewModel(
-            getCurrentUserIdUseCase = GetCurrentUserIdUseCase(authRepository = authRepository),
-            existsInitInfoUseCase = ExistsInitInfoUseCase(authRepository = authRepository)
+            getAuthStateStreamUseCase = GetAuthStateStreamUseCase(authRepository = authRepository)
         )
     }
 }

app/src/test/java/io/foundy/camstudy/fake/FakeAuthRepository.kt

@@ -1,19 +1,16 @@
 package io.foundy.camstudy.fake
 
+import io.foundy.auth.domain.model.AuthState
 import io.foundy.auth.domain.repository.AuthRepository
-import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.MutableSharedFlow
 
 class FakeAuthRepository : AuthRepository {
 
-    val currentUserIdSharedFlow = MutableSharedFlow<String?>(replay = 1)
+    override val stateStream: MutableSharedFlow<AuthState> = MutableSharedFlow(replay = 1)
 
-    var existsInitInfoTestValue: Boolean? = false
-
-    override val currentUserIdStream: Flow<String?> = currentUserIdSharedFlow
-
-    override val existsInitInfo: Boolean?
-        get() = existsInitInfoTestValue
+    suspend fun emitState(newState: AuthState) {
+        stateStream.emit(newState)
+    }
 
     override suspend fun markAsUserInitialInfoExists(userId: String) {
         TODO("Not yet implemented")

feature/auth/data/src/main/java/io/foundy/auth/data/repository/FirebaseAuthRepository.kt

@@ -4,6 +4,7 @@ import com.google.firebase.auth.ktx.auth
 import com.google.firebase.ktx.Firebase
 import io.foundy.auth.data.source.AuthLocalDataSource
 import io.foundy.auth.data.source.AuthRemoteDataSource
+import io.foundy.auth.domain.model.AuthState
 import io.foundy.auth.domain.repository.AuthRepository
 import io.foundy.core.common.di.ApplicationScope
 import io.foundy.core.data.extension.getDataOrThrowMessage
@@ -20,8 +21,7 @@ class FirebaseAuthRepository @Inject constructor(
     private val authLocalDataSource: AuthLocalDataSource
 ) : AuthRepository {
 
-    override val currentUserIdStream: MutableSharedFlow<String?> = MutableSharedFlow(replay = 1)
-    override var existsInitInfo: Boolean? = null
+    override val stateStream: MutableSharedFlow<AuthState> = MutableSharedFlow(replay = 1)
 
     init {
         Firebase.auth.addAuthStateListener { auth ->
@@ -36,25 +36,35 @@ class FirebaseAuthRepository @Inject constructor(
     private fun fetchAndNotify(currentUserId: String?) {
         externalScope.launch {
             if (currentUserId == null) {
-                existsInitInfo = null
-                currentUserIdStream.emit(null)
+                stateStream.emit(AuthState.NotSignedIn)
                 return@launch
             }
             val existsInLocal = authLocalDataSource.existsUserInitialInfo(currentUserId)
             if (existsInLocal) {
-                existsInitInfo = true
+                stateStream.emit(
+                    AuthState.SignedIn(
+                        currentUserId = currentUserId,
+                        existsInitInfo = true
+                    )
+                )
             } else {
                 runCatching {
                     val response = authRemoteDataSource.getUserInitialInfoExistence(currentUserId)
                     response.getDataOrThrowMessage()
                 }.onSuccess { exists ->
-                    existsInitInfo = exists
                     if (exists) {
                         authLocalDataSource.markAsUserInitialInfoExists(currentUserId)
                     }
+                    stateStream.emit(
+                        AuthState.SignedIn(
+                            currentUserId = currentUserId,
+                            existsInitInfo = exists
+                        )
+                    )
+                }.onFailure {
+                    stateStream.emit(AuthState.Error)
                 }
             }
-            currentUserIdStream.emit(currentUserId)
         }
     }
 }

feature/auth/domain/src/main/java/io/foundy/auth/domain/model/AuthState.kt

@@ -0,0 +1,7 @@
+package io.foundy.auth.domain.model
+
+sealed class AuthState {
+    object NotSignedIn : AuthState()
+    data class SignedIn(val currentUserId: String, val existsInitInfo: Boolean) : AuthState()
+    object Error : AuthState() // TODO: Add error context message
+}

feature/auth/domain/src/main/java/io/foundy/auth/domain/repository/AuthRepository.kt

@@ -1,15 +1,11 @@
 package io.foundy.auth.domain.repository
 
+import io.foundy.auth.domain.model.AuthState
 import kotlinx.coroutines.flow.Flow
 
 interface AuthRepository {
 
-    val currentUserIdStream: Flow<String?>
-
-    /**
-     * `currentUserIdStream`이 `true`인데 이 값이 `null`인 경우 서버와의 연결을 실패한 경우이다.
-     */
-    val existsInitInfo: Boolean?
+    val stateStream: Flow<AuthState>
 
     suspend fun markAsUserInitialInfoExists(userId: String)
 }

feature/auth/domain/src/main/java/io/foundy/auth/domain/usecase/GetCurrentUserIdStreamUseCase.kt → feature/auth/domain/src/main/java/io/foundy/auth/domain/usecase/GetAuthStateStreamUseCase.kt

@@ -1,13 +1,14 @@
 package io.foundy.auth.domain.usecase
 
+import io.foundy.auth.domain.model.AuthState
 import io.foundy.auth.domain.repository.AuthRepository
 import kotlinx.coroutines.flow.Flow
 import javax.inject.Inject
 
-class GetCurrentUserIdStreamUseCase @Inject constructor(
+class GetAuthStateStreamUseCase @Inject constructor(
     private val authRepository: AuthRepository
 ) {
-    operator fun invoke(): Flow<String?> {
-        return authRepository.currentUserIdStream
+    operator fun invoke(): Flow<AuthState> {
+        return authRepository.stateStream
     }
 }

feature/auth/domain/src/main/java/io/foundy/auth/domain/usecase/GetCurrentUserIdUseCase.kt

@@ -1,5 +1,6 @@
 package io.foundy.auth.domain.usecase
 
+import io.foundy.auth.domain.model.AuthState
 import io.foundy.auth.domain.repository.AuthRepository
 import kotlinx.coroutines.flow.firstOrNull
 import javax.inject.Inject
@@ -8,6 +9,9 @@ class GetCurrentUserIdUseCase @Inject constructor(
     private val authRepository: AuthRepository
 ) {
     suspend operator fun invoke(): String? {
-        return authRepository.currentUserIdStream.firstOrNull()
+        return when (val authState = authRepository.stateStream.firstOrNull()) {
+            is AuthState.SignedIn -> authState.currentUserId
+            else -> null
+        }
     }
 }

feature/auth/ui/src/main/java/io/foundy/auth/ui/LoginViewModel.kt

@@ -2,8 +2,8 @@ package io.foundy.auth.ui
 
 import androidx.lifecycle.ViewModel
 import dagger.hilt.android.lifecycle.HiltViewModel
-import io.foundy.auth.domain.usecase.ExistsInitInfoUseCase
-import io.foundy.auth.domain.usecase.GetCurrentUserIdStreamUseCase
+import io.foundy.auth.domain.model.AuthState
+import io.foundy.auth.domain.usecase.GetAuthStateStreamUseCase
 import org.orbitmvi.orbit.ContainerHost
 import org.orbitmvi.orbit.syntax.simple.intent
 import org.orbitmvi.orbit.syntax.simple.postSideEffect
@@ -13,31 +13,28 @@ import javax.inject.Inject
 
 @HiltViewModel
 class LoginViewModel @Inject constructor(
-    private val getCurrentUserIdStreamUseCase: GetCurrentUserIdStreamUseCase,
-    private val existsInitInfoUseCase: ExistsInitInfoUseCase
+    private val getAuthStateStreamUseCase: GetAuthStateStreamUseCase,
 ) : ViewModel(), ContainerHost<LoginUiState, LoginSideEffect> {
 
     override val container = container<LoginUiState, LoginSideEffect>(LoginUiState())
 
     init {
         intent {
-            getCurrentUserIdStreamUseCase().collect { uid ->
-                if (uid == null) {
-                    return@collect
-                }
-                val existsInitInfo = existsInitInfoUseCase()
-                if (existsInitInfo == null) {
-                    postSideEffect(
+            getAuthStateStreamUseCase().collect { authState ->
+                when (authState) {
+                    AuthState.Error -> postSideEffect(
                         LoginSideEffect.Message(
                             defaultMessageRes = R.string.failed_to_connect_server
                         )
                     )
-                    return@collect
-                }
-                if (existsInitInfo) {
-                    postSideEffect(LoginSideEffect.NavigateToHome)
-                } else {
-                    postSideEffect(LoginSideEffect.NavigateToWelcome)
+
+                    is AuthState.SignedIn -> if (authState.existsInitInfo) {
+                        postSideEffect(LoginSideEffect.NavigateToHome)
+                    } else {
+                        postSideEffect(LoginSideEffect.NavigateToWelcome)
+                    }
+
+                    AuthState.NotSignedIn -> {}
                 }
             }
         }

feature/room/ui/src/test/java/io/foundy/room/ui/fake/FakeAuthRepository.kt

@@ -1,15 +1,14 @@
 package io.foundy.room.ui.fake
 
+import io.foundy.auth.domain.model.AuthState
 import io.foundy.auth.domain.repository.AuthRepository
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.flow
 
 class FakeAuthRepository(private val userId: String = "1234") : AuthRepository {
 
-    override val currentUserIdStream: Flow<String?>
-        get() = flow { emit(userId) }
-
-    override val existsInitInfo: Boolean = true
+    override val stateStream: Flow<AuthState>
+        get() = flow { emit(AuthState.SignedIn(currentUserId = userId, existsInitInfo = true)) }
 
     override suspend fun markAsUserInitialInfoExists(userId: String) {
         TODO("Not yet implemented")