#44 first try at firebase use-cases

app/src/main/java/be/ugent/sel/studeez/data/local/models/User.kt

@@ -0,0 +1,3 @@
+package be.ugent.sel.studeez.data.local.models
+
+data class User(val id: String = "", val isAnonymous: Boolean = true)

app/src/main/java/be/ugent/sel/studeez/domain/Performance.kt

@@ -0,0 +1,27 @@
+/*
+Copyright 2022 Google LLC
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    https://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+ */
+
+package be.ugent.sel.studeez.domain
+
+import com.google.firebase.perf.ktx.trace
+import com.google.firebase.perf.metrics.Trace
+
+/**
+ * Trace a block with Firebase performance.
+ *
+ * Supports both suspend and regular methods.
+ */
+inline fun <T> trace(name: String, block: Trace.() -> T): T = Trace.create(name).trace(block)

app/src/main/java/be/ugent/sel/studeez/domain/account/AccountService.kt

@@ -0,0 +1,34 @@
+/*
+Copyright 2022 Google LLC
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    https://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+ */
+
+package be.ugent.sel.studeez.domain.account
+
+import be.ugent.sel.studeez.data.local.models.User
+import kotlinx.coroutines.flow.Flow
+
+interface AccountService {
+    val currentUserId: String
+    val hasUser: Boolean
+
+    val currentUser: Flow<User>
+
+    suspend fun authenticate(email: String, password: String)
+    suspend fun sendRecoveryEmail(email: String)
+    suspend fun createAnonymousAccount()
+    suspend fun linkAccount(email: String, password: String)
+    suspend fun deleteAccount()
+    suspend fun signOut()
+}

app/src/main/java/be/ugent/sel/studeez/domain/account/AccountServiceImpl.kt

@@ -0,0 +1,84 @@
+/*
+Copyright 2022 Google LLC
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    https://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+ */
+
+package be.ugent.sel.studeez.domain.account
+
+import be.ugent.sel.studeez.data.local.models.User
+import be.ugent.sel.studeez.domain.trace
+import com.google.firebase.auth.EmailAuthProvider
+import com.google.firebase.auth.FirebaseAuth
+import kotlinx.coroutines.channels.awaitClose
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.callbackFlow
+import kotlinx.coroutines.tasks.await
+import javax.inject.Inject
+
+class AccountServiceImpl @Inject constructor(
+    private val auth: FirebaseAuth
+) : AccountService {
+
+    override val currentUserId: String
+        get() = auth.currentUser?.uid.orEmpty()
+
+    override val hasUser: Boolean
+        get() = auth.currentUser != null
+
+    override val currentUser: Flow<User>
+        get() = callbackFlow {
+            val listener =
+                FirebaseAuth.AuthStateListener { auth ->
+                    this.trySend(auth.currentUser?.let { User(it.uid, it.isAnonymous) } ?: User())
+                }
+            auth.addAuthStateListener(listener)
+            awaitClose { auth.removeAuthStateListener(listener) }
+        }
+
+    override suspend fun authenticate(email: String, password: String) {
+        auth.signInWithEmailAndPassword(email, password).await()
+    }
+
+    override suspend fun sendRecoveryEmail(email: String) {
+        auth.sendPasswordResetEmail(email).await()
+    }
+
+    override suspend fun createAnonymousAccount() {
+        auth.signInAnonymously().await()
+    }
+
+    override suspend fun linkAccount(email: String, password: String): Unit =
+        trace(LINK_ACCOUNT_TRACE) {
+            val credential = EmailAuthProvider.getCredential(email, password)
+            auth.currentUser!!.linkWithCredential(credential).await()
+        }
+
+    override suspend fun deleteAccount() {
+        auth.currentUser!!.delete().await()
+    }
+
+    override suspend fun signOut() {
+        if (auth.currentUser!!.isAnonymous) {
+            auth.currentUser!!.delete()
+        }
+        auth.signOut()
+
+        // Sign the user back in anonymously.
+        createAnonymousAccount()
+    }
+
+    companion object {
+        private const val LINK_ACCOUNT_TRACE = "linkAccount"
+    }
+}

app/src/main/java/be/ugent/sel/studeez/domain/account/AuthenticateUseCase.kt

@@ -0,0 +1,13 @@
+package be.ugent.sel.studeez.domain.account
+
+import com.google.firebase.auth.FirebaseAuth
+import kotlinx.coroutines.tasks.await
+import javax.inject.Inject
+
+class AuthenticateUseCase @Inject constructor(
+    private val auth: FirebaseAuth,
+) {
+    suspend operator fun invoke(email: String, password: String) {
+        auth.signInWithEmailAndPassword(email, password).await()
+    }
+}

app/src/main/java/be/ugent/sel/studeez/domain/account/CreateAnonymousAccountUseCase.kt

@@ -0,0 +1,13 @@
+package be.ugent.sel.studeez.domain.account
+
+import com.google.firebase.auth.FirebaseAuth
+import kotlinx.coroutines.tasks.await
+import javax.inject.Inject
+
+class CreateAnonymousAccountUseCase @Inject constructor(
+    private val auth: FirebaseAuth,
+) {
+    suspend operator fun invoke() {
+        auth.signInAnonymously().await()
+    }
+}

app/src/main/java/be/ugent/sel/studeez/domain/account/DeleteAccountUseCase.kt

@@ -0,0 +1,13 @@
+package be.ugent.sel.studeez.domain.account
+
+import com.google.firebase.auth.FirebaseAuth
+import kotlinx.coroutines.tasks.await
+import javax.inject.Inject
+
+class DeleteAccountUseCase @Inject constructor(
+    private val auth: FirebaseAuth,
+) {
+    suspend operator fun invoke() {
+        auth.currentUser!!.delete().await()
+    }
+}

app/src/main/java/be/ugent/sel/studeez/domain/account/LinkAccountUseCase.kt

@@ -0,0 +1,22 @@
+package be.ugent.sel.studeez.domain.account
+
+import be.ugent.sel.studeez.domain.trace
+import com.google.firebase.auth.EmailAuthProvider
+import com.google.firebase.auth.FirebaseAuth
+import kotlinx.coroutines.tasks.await
+import javax.inject.Inject
+
+class LinkAccountUseCase @Inject constructor(
+    private val auth: FirebaseAuth,
+) {
+
+    suspend operator fun invoke(email: String, password: String): Unit =
+        trace(LINK_ACCOUNT_TRACE) {
+            val credential = EmailAuthProvider.getCredential(email, password)
+            auth.currentUser!!.linkWithCredential(credential).await()
+        }
+
+    companion object {
+        private const val LINK_ACCOUNT_TRACE = "linkAccount"
+    }
+}

app/src/main/java/be/ugent/sel/studeez/domain/account/SendRecoveryEmailUseCase.kt

@@ -0,0 +1,13 @@
+package be.ugent.sel.studeez.domain.account
+
+import com.google.firebase.auth.FirebaseAuth
+import kotlinx.coroutines.tasks.await
+import javax.inject.Inject
+
+class SendRecoveryEmailUseCase @Inject constructor(
+    private val auth: FirebaseAuth,
+) {
+    suspend operator fun invoke(email: String) {
+        auth.sendPasswordResetEmail(email).await()
+    }
+}

app/src/main/java/be/ugent/sel/studeez/domain/account/SignOutUseCase.kt

@@ -0,0 +1,18 @@
+package be.ugent.sel.studeez.domain.account
+
+import com.google.firebase.auth.FirebaseAuth
+import javax.inject.Inject
+
+class SignOutUseCase @Inject constructor(
+    private val auth: FirebaseAuth,
+    private val createAnonymousAccountUseCase: CreateAnonymousAccountUseCase,
+) {
+    suspend operator fun invoke() {
+        if (auth.currentUser!!.isAnonymous) {
+            auth.currentUser!!.delete()
+        }
+        auth.signOut()
+
+        createAnonymousAccountUseCase()
+    }
+}