Fix showing login/logout button on initial screens

app/src/main/java/gq/kirmanak/mealient/MainActivity.kt

@@ -51,7 +51,7 @@ class MainActivity : AppCompatActivity() {
 
     private fun listenToAuthStatuses() {
         Timber.v("listenToAuthStatuses() called")
-        authViewModel.authenticationState.observe(this, ::onAuthStateUpdate)
+        authViewModel.authenticationStateLive.observe(this, ::onAuthStateUpdate)
     }
 
     private fun onAuthStateUpdate(authState: AuthenticationState) {
@@ -71,12 +71,9 @@ class MainActivity : AppCompatActivity() {
     override fun onOptionsItemSelected(item: MenuItem): Boolean {
         Timber.v("onOptionsItemSelected() called with: item = $item")
         val result = when (item.itemId) {
-            R.id.logout -> {
-                authViewModel.logout()
-                true
-            }
-            R.id.login -> {
-                authViewModel.enableLoginRequest()
+            R.id.logout, R.id.login -> {
+                // When user clicks logout they don't want to be authorized
+                authViewModel.authRequested = item.itemId == R.id.login
                 true
             }
             else -> super.onOptionsItemSelected(item)

app/src/main/java/gq/kirmanak/mealient/ui/auth/AuthenticationFragment.kt

@@ -5,13 +5,12 @@ import android.view.View
 import androidx.appcompat.app.AppCompatActivity
 import androidx.fragment.app.Fragment
 import androidx.fragment.app.activityViewModels
-import androidx.lifecycle.LiveData
 import androidx.lifecycle.lifecycleScope
 import androidx.navigation.fragment.findNavController
 import by.kirich1409.viewbindingdelegate.viewBinding
 import dagger.hilt.android.AndroidEntryPoint
 import gq.kirmanak.mealient.R
-import gq.kirmanak.mealient.data.network.NetworkError.Unauthorized
+import gq.kirmanak.mealient.data.network.NetworkError
 import gq.kirmanak.mealient.databinding.FragmentAuthenticationBinding
 import gq.kirmanak.mealient.extensions.checkIfInputIsEmpty
 import gq.kirmanak.mealient.extensions.executeOnceOnBackPressed
@@ -22,14 +21,10 @@ class AuthenticationFragment : Fragment(R.layout.fragment_authentication) {
     private val binding by viewBinding(FragmentAuthenticationBinding::bind)
     private val viewModel by activityViewModels<AuthenticationViewModel>()
 
-    private val authStatuses: LiveData<AuthenticationState>
-        get() = viewModel.authenticationState
-
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         Timber.v("onCreate() called with: savedInstanceState = $savedInstanceState")
-        authStatuses.observe(this, ::onAuthStatusChange)
-        executeOnceOnBackPressed { viewModel.disableLoginRequest() }
+        executeOnceOnBackPressed { viewModel.authRequested = false }
     }
 
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
@@ -38,13 +33,7 @@ class AuthenticationFragment : Fragment(R.layout.fragment_authentication) {
         binding.button.setOnClickListener { onLoginClicked() }
         (requireActivity() as? AppCompatActivity)?.supportActionBar?.title =
             getString(R.string.app_name)
-    }
-
-    private fun onAuthStatusChange(isAuthenticated: AuthenticationState) {
-        Timber.v("onAuthStatusChange() called with: isAuthenticated = $isAuthenticated")
-        if (isAuthenticated == AuthenticationState.AUTHORIZED) {
-            findNavController().popBackStack()
-        }
+        viewModel.authenticationResult.observe(viewLifecycleOwner, ::onAuthenticationResult)
     }
 
     private fun onLoginClicked(): Unit = with(binding) {
@@ -59,14 +48,21 @@ class AuthenticationFragment : Fragment(R.layout.fragment_authentication) {
         } ?: return
 
         button.isClickable = false
-        viewModel.authenticate(email, pass).observe(viewLifecycleOwner) {
-            Timber.d("onLoginClicked: result $it")
-            passwordInputLayout.error = when (it.exceptionOrNull()) {
-                is Unauthorized -> getString(R.string.fragment_authentication_credentials_incorrect)
-                else -> null
-            }
+        viewModel.authenticate(email, pass)
+    }
 
-            button.isClickable = true
+    private fun onAuthenticationResult(result: Result<Unit>) {
+        Timber.v("onAuthenticationResult() called with: result = $result")
+        if (result.isSuccess) {
+            findNavController().popBackStack()
+            return
         }
+
+        binding.passwordInputLayout.error = when (result.exceptionOrNull()) {
+            is NetworkError.Unauthorized -> getString(R.string.fragment_authentication_credentials_incorrect)
+            else -> null
+        }
+
+        binding.button.isClickable = true
     }
 }

app/src/main/java/gq/kirmanak/mealient/ui/auth/AuthenticationState.kt

@@ -5,16 +5,19 @@ import timber.log.Timber
 enum class AuthenticationState {
     AUTHORIZED,
     AUTH_REQUESTED,
-    UNAUTHORIZED;
+    UNAUTHORIZED,
+    UNKNOWN;
 
     companion object {
 
         fun determineState(
             isLoginRequested: Boolean,
+            showLoginButton: Boolean,
             isAuthorized: Boolean,
         ): AuthenticationState {
-            Timber.v("determineState() called with: isLoginRequested = $isLoginRequested, isAuthorized = $isAuthorized")
+            Timber.v("determineState() called with: isLoginRequested = $isLoginRequested, showLoginButton = $showLoginButton, isAuthorized = $isAuthorized")
             val result = when {
+                !showLoginButton -> UNKNOWN
                 isAuthorized -> AUTHORIZED
                 isLoginRequested -> AUTH_REQUESTED
                 else -> UNAUTHORIZED

app/src/main/java/gq/kirmanak/mealient/ui/auth/AuthenticationViewModel.kt

@@ -4,6 +4,7 @@ import androidx.lifecycle.*
 import dagger.hilt.android.lifecycle.HiltViewModel
 import gq.kirmanak.mealient.data.auth.AuthRepo
 import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.collect
 import kotlinx.coroutines.flow.combine
 import kotlinx.coroutines.launch
 import timber.log.Timber
@@ -14,48 +15,44 @@ class AuthenticationViewModel @Inject constructor(
     private val authRepo: AuthRepo,
 ) : ViewModel() {
 
-    private val loginRequestsFlow = MutableStateFlow(false)
-    val authenticationState: LiveData<AuthenticationState> = loginRequestsFlow.combine(
-        flow = authRepo.isAuthorizedFlow,
-        transform = AuthenticationState::determineState
-    ).asLiveData()
+    private val authRequestsFlow = MutableStateFlow(false)
+    private val showLoginButtonFlow = MutableStateFlow(false)
+    private val authenticationStateFlow = combine(
+        authRequestsFlow,
+        showLoginButtonFlow,
+        authRepo.isAuthorizedFlow,
+        AuthenticationState::determineState
+    )
+    val authenticationStateLive: LiveData<AuthenticationState>
+        get() = authenticationStateFlow.asLiveData()
+    var authRequested: Boolean by authRequestsFlow::value
+    var showLoginButton: Boolean by showLoginButtonFlow::value
 
-    fun authenticate(username: String, password: String): LiveData<Result<Unit>> {
+    private val _authenticationResult = MutableLiveData<Result<Unit>>()
+    val authenticationResult: LiveData<Result<Unit>>
+        get() = _authenticationResult
+
+    init {
+        viewModelScope.launch {
+            authRequestsFlow.collect { isRequested ->
+                // Clear auth token on logout request
+                if (!isRequested) authRepo.logout()
+            }
+        }
+    }
+
+    fun authenticate(username: String, password: String) {
         Timber.v("authenticate() called with: username = $username, password = $password")
-        val result = MutableLiveData<Result<Unit>>()
         viewModelScope.launch {
             runCatching {
                 authRepo.authenticate(username, password)
             }.onFailure {
                 Timber.e(it, "authenticate: can't authenticate")
-                result.value = Result.failure(it)
+                _authenticationResult.value = Result.failure(it)
             }.onSuccess {
                 Timber.d("authenticate: authenticated")
-                result.value = Result.success(Unit)
+                _authenticationResult.value = Result.success(Unit)
             }
         }
-        return result
-    }
-
-    fun logout() {
-        Timber.v("logout() called")
-        viewModelScope.launch {
-            loginRequestsFlow.emit(false)
-            authRepo.logout()
-        }
-    }
-
-    fun enableLoginRequest() {
-        Timber.v("enableLoginRequest() called")
-        updateIsLoginRequested(true)
-    }
-
-    fun disableLoginRequest() {
-        Timber.v("disableLoginRequest() called")
-        updateIsLoginRequested(false)
-    }
-
-    private fun updateIsLoginRequested(isRequested: Boolean) {
-        viewModelScope.launch { loginRequestsFlow.emit(isRequested) }
     }
 }

app/src/main/java/gq/kirmanak/mealient/ui/recipes/RecipesFragment.kt

@@ -27,7 +27,8 @@ class RecipesFragment : Fragment(R.layout.fragment_recipes) {
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
-        authViewModel.authenticationState.observe(this, ::onAuthStateChange)
+        Timber.v("onCreate() called with: savedInstanceState = $savedInstanceState")
+        authViewModel.authenticationStateLive.observe(this, ::onAuthStateChange)
     }
 
     private fun onAuthStateChange(authenticationState: AuthenticationState) {
@@ -40,6 +41,7 @@ class RecipesFragment : Fragment(R.layout.fragment_recipes) {
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
         super.onViewCreated(view, savedInstanceState)
         Timber.v("onViewCreated() called with: view = $view, savedInstanceState = $savedInstanceState")
+        authViewModel.showLoginButton = true
         setupRecipeAdapter()
         (requireActivity() as? AppCompatActivity)?.supportActionBar?.title = null
     }
@@ -78,5 +80,6 @@ class RecipesFragment : Fragment(R.layout.fragment_recipes) {
         Timber.v("onDestroyView() called")
         // Prevent RV leaking through mObservers list in adapter
         binding.recipes.adapter = null
+        authViewModel.showLoginButton = false
     }
 }