Completely rewrite provider login with new architecture

app/build.gradle

@@ -38,7 +38,7 @@ android {
 dependencies {
     implementation "com.google.firebase:firebase-core:$firebaseVersion"
     implementation "com.android.support:design:$supportLibraryVersion"
-    implementation 'com.android.support:multidex:1.0.2'
+    implementation 'com.android.support:multidex:1.0.3'
 
     implementation project(path: ':auth')
     implementation project(path: ':firestore')

auth/src/main/AndroidManifest.xml

@@ -23,10 +23,17 @@
             android:exported="false"
             android:theme="@style/FirebaseUI.Transparent" />
 
+        <activity
+            android:name=".ui.idp.SingleSignInActivity"
+            android:label=""
+            android:exported="false"
+            android:theme="@style/FirebaseUI.Transparent" />
+
         <activity
             android:name=".ui.email.RecoverPasswordActivity"
             android:label="@string/fui_title_recover_password_activity"
-            android:exported="false" />
+            android:exported="false"
+            android:windowSoftInputMode="adjustResize" />
 
         <activity
             android:name=".ui.email.EmailActivity"
@@ -43,7 +50,8 @@
         <activity
             android:name=".ui.idp.WelcomeBackIdpPrompt"
             android:label="@string/fui_title_welcome_back_idp_prompt"
-            android:exported="false" />
+            android:exported="false"
+            android:windowSoftInputMode="adjustResize" />
 
         <activity
             android:name=".ui.email.WelcomeBackPasswordPrompt"

auth/src/main/java/com/firebase/ui/auth/AuthUI.java

@@ -31,7 +31,8 @@
 
 import com.facebook.login.LoginManager;
 import com.firebase.ui.auth.data.model.FlowParameters;
-import com.firebase.ui.auth.provider.TwitterProvider;
+import com.firebase.ui.auth.data.remote.FacebookSignInHandler;
+import com.firebase.ui.auth.data.remote.TwitterSignInHandler;
 import com.firebase.ui.auth.ui.idp.AuthMethodPickerActivity;
 import com.firebase.ui.auth.util.ExtraConstants;
 import com.firebase.ui.auth.util.GoogleApiUtils;
@@ -59,6 +60,7 @@
 import com.google.firebase.auth.PhoneAuthProvider;
 import com.google.firebase.auth.TwitterAuthProvider;
 import com.google.firebase.auth.UserInfo;
+import com.twitter.sdk.android.core.TwitterCore;
 
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
@@ -177,10 +179,10 @@ public class AuthUI {
      */
     public static final Set<String> SUPPORTED_PROVIDERS =
             Collections.unmodifiableSet(new HashSet<>(Arrays.asList(
-                    EmailAuthProvider.PROVIDER_ID,
                     GoogleAuthProvider.PROVIDER_ID,
                     FacebookAuthProvider.PROVIDER_ID,
                     TwitterAuthProvider.PROVIDER_ID,
+                    EmailAuthProvider.PROVIDER_ID,
                     PhoneAuthProvider.PROVIDER_ID
             )));
 
@@ -276,7 +278,7 @@ public Task<Void> signOut(@NonNull Context context) {
                 .disableAutoSignIn()
                 .continueWithTask(new Continuation<Void, Task<Void>>() {
                     @Override
-                    public Task<Void> then(@NonNull Task<Void> task) throws Exception {
+                    public Task<Void> then(@NonNull Task<Void> task) {
                         // We want to ignore a specific exception, since it's not a good reason
                         // to fail (see Issue 1156).
                         if (!task.isSuccessful() && (task.getException() instanceof ApiException)) {
@@ -357,22 +359,12 @@ public Task<Void> then(@NonNull Task<Void> task) {
     }
 
     private Task<Void> signOutIdps(@NonNull Context context) {
-        try {
+        if (FacebookSignInHandler.IS_AVAILABLE) {
             LoginManager.getInstance().logOut();
-        } catch (NoClassDefFoundError e) {
-            // Do nothing: this is perfectly fine if the dev doesn't include Facebook/Twitter
-            // support
         }
-
-        try {
-            TwitterProvider.signOut(context);
-        } catch (NoClassDefFoundError e) {
-            // See comment above
-            // Note: we need to have separate try/catch statements since devs can include
-            // _either_ one of the providers. If one crashes, we still need to sign out of
-            // the other one.
+        if (TwitterSignInHandler.IS_AVAILABLE) {
+            TwitterCore.getInstance().getSessionManager().clearActiveSession();
         }
-
         return GoogleSignIn.getClient(context, GoogleSignInOptions.DEFAULT_SIGN_IN).signOut();
     }
 
@@ -787,17 +779,12 @@ public static final class FacebookBuilder extends Builder {
             public FacebookBuilder() {
                 //noinspection deprecation taking a hit for the backcompat team
                 super(FacebookAuthProvider.PROVIDER_ID);
-
-                try {
-                    //noinspection unused to possibly throw
-                    Class c = com.facebook.FacebookSdk.class;
-                } catch (NoClassDefFoundError e) {
+                if (!FacebookSignInHandler.IS_AVAILABLE) {
                     throw new RuntimeException(
                             "Facebook provider cannot be configured " +
                                     "without dependency. Did you forget to add " +
                                     "'com.facebook.android:facebook-login:VERSION' dependency?");
                 }
-
                 Preconditions.checkConfigured(getApplicationContext(),
                         "Facebook provider unconfigured. Make sure to add a" +
                                 " `facebook_application_id` string. See the docs for more info:" +
@@ -830,17 +817,12 @@ public static final class TwitterBuilder extends Builder {
             public TwitterBuilder() {
                 //noinspection deprecation taking a hit for the backcompat team
                 super(TwitterAuthProvider.PROVIDER_ID);
-
-                try {
-                    //noinspection unused to possibly throw
-                    Class c = com.twitter.sdk.android.core.TwitterCore.class;
-                } catch (NoClassDefFoundError e) {
+                if (!TwitterSignInHandler.IS_AVAILABLE) {
                     throw new RuntimeException(
                             "Twitter provider cannot be configured " +
                                     "without dependency. Did you forget to add " +
                                     "'com.twitter.sdk.android:twitter-core:VERSION' dependency?");
                 }
-
                 Preconditions.checkConfigured(getApplicationContext(),
                         "Twitter provider unconfigured. Make sure to add your key and secret." +
                                 " See the docs for more info:" +

auth/src/main/java/com/firebase/ui/auth/ErrorCodes.java

@@ -16,7 +16,8 @@ public final class ErrorCodes {
                     UNKNOWN_ERROR,
                     NO_NETWORK,
                     PLAY_SERVICES_UPDATE_CANCELLED,
-                    DEVELOPER_ERROR
+                    DEVELOPER_ERROR,
+                    PROVIDER_ERROR
             })
     @Retention(RetentionPolicy.SOURCE)
     public @interface Code {}
@@ -41,6 +42,11 @@ public final class ErrorCodes {
      */
     public static final int DEVELOPER_ERROR = 3;
 
+    /**
+     * An external sign-in provider error occurred.
+     */
+    public static final int PROVIDER_ERROR = 4;
+
     private ErrorCodes() {
         throw new AssertionError("No instance for you!");
     }

auth/src/main/java/com/firebase/ui/auth/IdpResponse.java

@@ -23,6 +23,7 @@
 import android.support.annotation.RestrictTo;
 import android.text.TextUtils;
 
+import com.firebase.ui.auth.data.model.Resource;
 import com.firebase.ui.auth.data.model.User;
 import com.firebase.ui.auth.util.ExtraConstants;
 import com.google.firebase.auth.GoogleAuthProvider;
@@ -97,20 +98,33 @@ public static IdpResponse fromResultIntent(@Nullable Intent resultIntent) {
         }
     }
 
+    @NonNull
     @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
-    public static Intent getErrorIntent(@NonNull Exception e) {
-        return fromError(e).toIntent();
+    public static IdpResponse from(@NonNull Resource<IdpResponse> resource) {
+        IdpResponse response = resource.getValue();
+        if (resource.getException() != null) {
+            response = from(resource.getException());
+        }
+        return response;
     }
 
+    @NonNull
     @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
-    public static IdpResponse fromError(@NonNull Exception e) {
+    public static IdpResponse from(@NonNull Exception e) {
         if (e instanceof FirebaseUiException) {
             return new IdpResponse((FirebaseUiException) e);
         } else {
             return new IdpResponse(new FirebaseUiException(ErrorCodes.UNKNOWN_ERROR, e));
         }
     }
 
+    @NonNull
+    @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
+    public static Intent getErrorIntent(@NonNull Exception e) {
+        return from(e).toIntent();
+    }
+
+    @NonNull
     @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
     public Intent toIntent() {
         return new Intent().putExtra(ExtraConstants.EXTRA_IDP_RESPONSE, this);

auth/src/main/java/com/firebase/ui/auth/KickoffActivity.java

@@ -13,12 +13,12 @@
 import com.firebase.ui.auth.util.ExtraConstants;
 import com.firebase.ui.auth.util.PlayServicesHelper;
 import com.firebase.ui.auth.util.signincontainer.SignInDelegate;
+import com.firebase.ui.auth.viewmodel.RequestCodes;
 
 @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
 public class KickoffActivity extends HelperActivityBase {
     private static final String TAG = "KickoffActivity";
     private static final String IS_WAITING_FOR_PLAY_SERVICES = "is_waiting_for_play_services";
-    private static final int RC_PLAY_SERVICES = 1;
 
     private boolean mIsWaitingForPlayServices = false;
 
@@ -40,7 +40,7 @@ protected void onCreate(Bundle savedInstance) {
 
             boolean isPlayServicesAvailable = PlayServicesHelper.makePlayServicesAvailable(
                     this,
-                    RC_PLAY_SERVICES,
+                    RequestCodes.PLAY_SERVICES_CHECK,
                     new DialogInterface.OnCancelListener() {
                         @Override
                         public void onCancel(DialogInterface dialog) {
@@ -68,7 +68,7 @@ public void onSaveInstanceState(Bundle outState) {
     @Override
     protected void onActivityResult(int requestCode, int resultCode, Intent data) {
         super.onActivityResult(requestCode, resultCode, data);
-        if (requestCode == RC_PLAY_SERVICES) {
+        if (requestCode == RequestCodes.PLAY_SERVICES_CHECK) {
             if (resultCode == RESULT_OK) {
                 start();
             } else {

auth/src/main/java/com/firebase/ui/auth/data/model/Resource.java

@@ -12,15 +12,15 @@
  */
 @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
 public final class Resource<T> {
+    private State mState;
+    private final boolean mUsable;
 
-    private final State mState;
     private final T mValue;
     private final Exception mException;
 
-    private boolean mUsed;
-
-    private Resource(State state, T value, Exception exception) {
+    private Resource(State state, boolean usable, T value, Exception exception) {
         mState = state;
+        mUsable = usable;
         mValue = value;
         mException = exception;
     }
@@ -30,31 +30,47 @@ private Resource(State state, T value, Exception exception) {
      */
     @NonNull
     public static Resource<Void> forVoidSuccess() {
-        return new Resource<>(State.SUCCESS, null, null);
+        return new Resource<>(State.SUCCESS, false, null, null);
     }
 
     /**
      * Creates a successful resource containing a value.
      */
     @NonNull
     public static <T> Resource<T> forSuccess(@NonNull T value) {
-        return new Resource<>(State.SUCCESS, value, null);
+        return new Resource<>(State.SUCCESS, false, value, null);
+    }
+
+    /**
+     * Similar to {@link #forSuccess(Object)}, but this resource can be used up.
+     */
+    @NonNull
+    public static <T> Resource<T> forUsableSuccess(@NonNull T value) {
+        return new Resource<>(State.SUCCESS, true, value, null);
     }
 
     /**
      * Creates a failed resource with an exception.
      */
     @NonNull
     public static <T> Resource<T> forFailure(@NonNull Exception e) {
-        return new Resource<>(State.FAILURE, null, e);
+        return new Resource<>(State.FAILURE, false, null, e);
+    }
+
+    /**
+     * Similar to {@link #forFailure(Exception)}, but this resource can be used up.
+     */
+    @NonNull
+    public static <T> Resource<T> forUsableFailure(@NonNull Exception e) {
+        return new Resource<>(State.FAILURE, true, null, e);
     }
 
     /**
      * Creates a resource in the loading state, without a value or an exception.
      */
     @NonNull
     public static <T> Resource<T> forLoading() {
-        return new Resource<>(State.LOADING, null, null);
+        return new Resource<>(State.LOADING, false, null, null);
     }
 
     @NonNull
@@ -64,20 +80,16 @@ public State getState() {
 
     @Nullable
     public final Exception getException() {
-        mUsed = true;
+        if (mUsable) { mState = State.USED; }
         return mException;
     }
 
     @Nullable
     public T getValue() {
-        mUsed = true;
+        if (mUsable) { mState = State.USED; }
         return mValue;
     }
 
-    public boolean isUsed() {
-        return mUsed;
-    }
-
     @Override
     public boolean equals(Object o) {
         if (this == o) return true;

auth/src/main/java/com/firebase/ui/auth/data/model/State.java

@@ -4,5 +4,5 @@
 
 @RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
 public enum State {
-    SUCCESS, FAILURE, LOADING
+    SUCCESS, FAILURE, LOADING, USED
 }

auth/src/main/java/com/firebase/ui/auth/data/model/UserCancellationException.java

@@ -0,0 +1,13 @@
+package com.firebase.ui.auth.data.model;
+
+import android.support.annotation.RestrictTo;
+
+import com.firebase.ui.auth.ErrorCodes;
+import com.firebase.ui.auth.FirebaseUiException;
+
+@RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
+public class UserCancellationException extends FirebaseUiException {
+    public UserCancellationException() {
+        super(ErrorCodes.UNKNOWN_ERROR);
+    }
+}

auth/src/main/java/com/firebase/ui/auth/data/remote/EmailSignInHandler.java

@@ -0,0 +1,41 @@
+package com.firebase.ui.auth.data.remote;
+
+import android.app.Application;
+import android.content.Intent;
+import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
+import android.support.annotation.RestrictTo;
+
+import com.firebase.ui.auth.IdpResponse;
+import com.firebase.ui.auth.data.model.Resource;
+import com.firebase.ui.auth.data.model.UserCancellationException;
+import com.firebase.ui.auth.ui.HelperActivityBase;
+import com.firebase.ui.auth.ui.email.EmailActivity;
+import com.firebase.ui.auth.viewmodel.RequestCodes;
+import com.firebase.ui.auth.viewmodel.idp.ProviderSignInBase;
+
+@RestrictTo(RestrictTo.Scope.LIBRARY_GROUP)
+public class EmailSignInHandler extends ProviderSignInBase<Void> {
+    public EmailSignInHandler(Application application) {
+        super(application);
+    }
+
+    @Override
+    public void startSignIn(@NonNull HelperActivityBase activity) {
+        activity.startActivityForResult(
+                EmailActivity.createIntent(activity, activity.getFlowParams()),
+                RequestCodes.EMAIL_FLOW);
+    }
+
+    @Override
+    public void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
+        if (requestCode == RequestCodes.EMAIL_FLOW) {
+            IdpResponse response = IdpResponse.fromResultIntent(data);
+            if (response == null) {
+                setResult(Resource.<IdpResponse>forFailure(new UserCancellationException()));
+            } else {
+                setResult(Resource.forSuccess(response));
+            }
+        }
+    }
+}