issue #54: The app requires the user name when he enter in session

fix #54

When the user open the Session Activity (after create a
new session or when it click on a shared link) the app will check if
there are an user on shared preferences. If there is not any, the app
will require a name

app/src/main/java/br/org/cesar/discordtime/stickysessions/data/local/repository/UserLocalRepository.java

@@ -0,0 +1,57 @@
+package br.org.cesar.discordtime.stickysessions.data.local.repository;
+
+import android.content.Context;
+import android.content.SharedPreferences;
+
+import br.org.cesar.discordtime.stickysessions.domain.repository.UserRepository;
+import io.reactivex.Single;
+import io.reactivex.SingleEmitter;
+import io.reactivex.SingleOnSubscribe;
+
+public class UserLocalRepository implements UserRepository {
+
+    private static final String USER_KEY = "user";
+
+    private final Context mContext;
+    private final String mSharedPrefs;
+
+    public UserLocalRepository(Context context, String sharedPrefsName) {
+        mContext = context;
+        mSharedPrefs = sharedPrefsName;
+    }
+
+    @Override
+    public Single<Boolean> saveUser(String user) {
+        return Single.create(emitter -> {
+            SharedPreferences prefs =
+                mContext.getSharedPreferences(mSharedPrefs, Context.MODE_PRIVATE);
+            SharedPreferences.Editor editor = prefs.edit();
+            editor.putString(USER_KEY, user);
+
+            if (editor.commit()) {
+                emitter.onSuccess(true);
+            } else {
+                emitter.onError(
+                    new Exception("The user could not be saved into local repository")
+                );
+            }
+        });
+    }
+
+    @Override
+    public Single<String> getSavedUser() {
+        return Single.create(emitter -> {
+            SharedPreferences prefs =
+                mContext.getSharedPreferences(mSharedPrefs, Context.MODE_PRIVATE);
+            String userSaved = prefs.getString(USER_KEY, null);
+            if (userSaved != null) {
+                emitter.onSuccess(userSaved);
+            } else {
+                emitter.onError(new Exception("User Not found"));
+            }
+
+
+        });
+
+    }
+}

app/src/main/java/br/org/cesar/discordtime/stickysessions/data/remote/repository/NoteRemoteRepository.java

@@ -7,6 +7,7 @@
 import br.org.cesar.discordtime.stickysessions.data.remote.service.NoteService;
 import br.org.cesar.discordtime.stickysessions.data.repository.mapper.Mapper;
 import br.org.cesar.discordtime.stickysessions.domain.model.Note;
+import br.org.cesar.discordtime.stickysessions.domain.model.NoteFilter;
 import br.org.cesar.discordtime.stickysessions.domain.repository.NoteRepository;
 import io.reactivex.Single;
 
@@ -30,8 +31,8 @@ public Single<Note> addNote(Note note) {
     }
 
     @Override
-    public Single<List<Note>> listNotesForSession(String id) {
-        return mNoteService.listNotesForSession(id).map(
+    public Single<List<Note>> listNotesForSession(NoteFilter noteFilter) {
+        return mNoteService.listNotesForSession(noteFilter.idSession, noteFilter.user).map(
             noteRemotes -> {
                 List<Note> mNotes = new ArrayList<>();
 

app/src/main/java/br/org/cesar/discordtime/stickysessions/data/remote/service/NoteService.java

@@ -13,6 +13,6 @@ public interface NoteService {
     @POST("/notes")
     Single<NoteRemote> addNote(@Body NoteRemote note);
 
-    @GET("/notes/{id}")
-    Single<List<NoteRemote>> listNotesForSession(@Path("id") String id);
+    @GET("/notes/{id}/{user}")
+    Single<List<NoteRemote>> listNotesForSession(@Path("id") String id, @Path("user") String user);
 }

app/src/main/java/br/org/cesar/discordtime/stickysessions/domain/interactor/GetLocalUser.java

@@ -0,0 +1,19 @@
+package br.org.cesar.discordtime.stickysessions.domain.interactor;
+
+import br.org.cesar.discordtime.stickysessions.domain.repository.UserRepository;
+import io.reactivex.Single;
+import io.reactivex.SingleObserver;
+
+public class GetLocalUser extends UseCase<Void,String> {
+
+    private final UserRepository mUserRepository;
+
+    public GetLocalUser(UserRepository repository) {
+        mUserRepository = repository;
+    }
+
+    @Override
+    public Single<String> execute(Void params) {
+        return mUserRepository.getSavedUser();
+    }
+}

app/src/main/java/br/org/cesar/discordtime/stickysessions/domain/interactor/ListNotesForSession.java

@@ -3,11 +3,12 @@
 import java.util.List;
 
 import br.org.cesar.discordtime.stickysessions.domain.model.Note;
+import br.org.cesar.discordtime.stickysessions.domain.model.NoteFilter;
 import br.org.cesar.discordtime.stickysessions.domain.repository.NoteRepository;
 import br.org.cesar.discordtime.stickysessions.domain.repository.SessionRepository;
 import io.reactivex.Single;
 
-public class ListNotesForSession extends UseCase<String, List<Note>> {
+public class ListNotesForSession extends UseCase<NoteFilter, List<Note>> {
 
     private final NoteRepository mNoteRepository;
     private final SessionRepository mSessionRepository;
@@ -18,14 +19,14 @@ public ListNotesForSession(NoteRepository noteRepository, SessionRepository sess
     }
 
     @Override
-    public Single<List<Note>> execute(String sessionId) {
-        return mSessionRepository.getSession(sessionId).flatMap(
+    public Single<List<Note>> execute(NoteFilter noteFilter) {
+        return mSessionRepository.getSession(noteFilter.idSession).flatMap(
             session -> {
                 if (session == null) {
                     return Single.error(new Exception("The Session does not exist"));
                 }
 
-                return mNoteRepository.listNotesForSession(sessionId);
+                return mNoteRepository.listNotesForSession(noteFilter);
             }
         );
     }

app/src/main/java/br/org/cesar/discordtime/stickysessions/domain/interactor/SaveCurrentUser.java

@@ -0,0 +1,23 @@
+package br.org.cesar.discordtime.stickysessions.domain.interactor;
+
+import br.org.cesar.discordtime.stickysessions.domain.repository.UserRepository;
+import io.reactivex.Single;
+
+public class SaveCurrentUser extends UseCase<String, Boolean> {
+
+    private UserRepository mUserRepository;
+
+    public SaveCurrentUser(UserRepository userRepository) {
+        mUserRepository = userRepository;
+    }
+
+    @Override
+    public Single<Boolean> execute(String userName) {
+
+        if (userName == null || userName.trim().isEmpty()) {
+            return Single.error(new Exception("The user is invalid (null or empty)"));
+        }
+
+        return mUserRepository.saveUser(userName);
+    }
+}

app/src/main/java/br/org/cesar/discordtime/stickysessions/domain/model/NoteFilter.java

@@ -0,0 +1,12 @@
+package br.org.cesar.discordtime.stickysessions.domain.model;
+
+public class NoteFilter {
+
+    public String user;
+    public String idSession;
+
+    public NoteFilter(String idSession, String user) {
+        this.user = user;
+        this.idSession = idSession;
+    }
+}

app/src/main/java/br/org/cesar/discordtime/stickysessions/domain/repository/NoteRepository.java

@@ -3,9 +3,10 @@
 import java.util.List;
 
 import br.org.cesar.discordtime.stickysessions.domain.model.Note;
+import br.org.cesar.discordtime.stickysessions.domain.model.NoteFilter;
 import io.reactivex.Single;
 
 public interface NoteRepository {
     Single<Note> addNote(Note note);
-    Single<List<Note>> listNotesForSession(String id);
+    Single<List<Note>> listNotesForSession(NoteFilter noteFilter);
 }

app/src/main/java/br/org/cesar/discordtime/stickysessions/domain/repository/UserRepository.java

@@ -0,0 +1,8 @@
+package br.org.cesar.discordtime.stickysessions.domain.repository;
+
+import io.reactivex.Single;
+
+public interface UserRepository {
+    Single<Boolean> saveUser(String user);
+    Single<String> getSavedUser();
+}

app/src/main/java/br/org/cesar/discordtime/stickysessions/injectors/components/SessionComponent.java

@@ -6,6 +6,7 @@
 import br.org.cesar.discordtime.stickysessions.injectors.modules.SessionModule;
 import br.org.cesar.discordtime.stickysessions.injectors.modules.SessionPresenterModule;
 import br.org.cesar.discordtime.stickysessions.injectors.modules.ThreadModule;
+import br.org.cesar.discordtime.stickysessions.injectors.modules.UserModule;
 import br.org.cesar.discordtime.stickysessions.ui.session.SessionActivity;
 import dagger.Component;
 
@@ -16,7 +17,8 @@
         SessionModule.class,
         ThreadModule.class,
         ContextModule.class,
-        ServerModule.class
+        ServerModule.class,
+        UserModule.class
     }
 )
 public interface SessionComponent {

app/src/main/java/br/org/cesar/discordtime/stickysessions/injectors/modules/NoteModule.java

@@ -13,6 +13,7 @@
 import br.org.cesar.discordtime.stickysessions.domain.interactor.AddNote;
 import br.org.cesar.discordtime.stickysessions.domain.interactor.ListNotesForSession;
 import br.org.cesar.discordtime.stickysessions.domain.model.Note;
+import br.org.cesar.discordtime.stickysessions.domain.model.NoteFilter;
 import br.org.cesar.discordtime.stickysessions.domain.repository.NoteRepository;
 import br.org.cesar.discordtime.stickysessions.domain.repository.SessionRepository;
 import br.org.cesar.discordtime.stickysessions.executor.ObservableUseCase;
@@ -35,7 +36,7 @@ public ObservableUseCase<Note, Note> provideObservableAddNoteUseCase(
     }
 
     @Provides
-    public ObservableUseCase<String, List<Note>> provideObservableListNotesUseCase(
+    public ObservableUseCase<NoteFilter, List<Note>> provideObservableListNotesUseCase(
         ListNotesForSession listNotesForSession, ThreadExecutor threadExecutor,
         PostExecutionThread postExecutionThread
     ) {

app/src/main/java/br/org/cesar/discordtime/stickysessions/injectors/modules/SessionPresenterModule.java

@@ -3,6 +3,7 @@
 import java.util.List;
 
 import br.org.cesar.discordtime.stickysessions.domain.model.Note;
+import br.org.cesar.discordtime.stickysessions.domain.model.NoteFilter;
 import br.org.cesar.discordtime.stickysessions.domain.model.Session;
 import br.org.cesar.discordtime.stickysessions.executor.ObservableUseCase;
 import br.org.cesar.discordtime.stickysessions.presentation.session.SessionContract;
@@ -17,9 +18,11 @@ public class SessionPresenterModule {
     public SessionContract.Presenter providesPresenter(
         ObservableUseCase<String, Session> enterSession,
         ObservableUseCase<Note, Note> addNote,
-        ObservableUseCase<String, List<Note>> listNotes){
+        ObservableUseCase<NoteFilter, List<Note>> listNotes,
+        ObservableUseCase<String, Boolean> saveCurrentUser,
+        ObservableUseCase<Void, String> getSavedUser){
 
-        return new SessionPresenter(enterSession, addNote, listNotes);
+        return new SessionPresenter(enterSession, addNote, listNotes, saveCurrentUser, getSavedUser);
     }
 
 }

app/src/main/java/br/org/cesar/discordtime/stickysessions/injectors/modules/UserModule.java

@@ -0,0 +1,57 @@
+package br.org.cesar.discordtime.stickysessions.injectors.modules;
+
+import android.content.Context;
+
+import javax.inject.Named;
+
+import br.org.cesar.discordtime.stickysessions.data.local.repository.UserLocalRepository;
+import br.org.cesar.discordtime.stickysessions.domain.interactor.GetLocalUser;
+import br.org.cesar.discordtime.stickysessions.domain.interactor.SaveCurrentUser;
+import br.org.cesar.discordtime.stickysessions.domain.repository.UserRepository;
+import br.org.cesar.discordtime.stickysessions.executor.ObservableUseCase;
+import br.org.cesar.discordtime.stickysessions.executor.PostExecutionThread;
+import br.org.cesar.discordtime.stickysessions.executor.ThreadExecutor;
+import dagger.Module;
+import dagger.Provides;
+
+@Module
+public class UserModule {
+
+    @Provides
+    public ObservableUseCase<String, Boolean> providesObservableSaveCurrentUser(
+        SaveCurrentUser saveCurrentUser,
+        ThreadExecutor threadExecutor,
+        PostExecutionThread postExecutionThread) {
+        return new ObservableUseCase<>(saveCurrentUser, threadExecutor, postExecutionThread);
+    }
+
+    @Provides
+    public ObservableUseCase<Void, String> providesObservableGetSavedUser(
+        GetLocalUser getLocalUser, ThreadExecutor threadExecutor,
+        PostExecutionThread postExecutionThread) {
+
+        return new ObservableUseCase<>(getLocalUser, threadExecutor, postExecutionThread);
+    }
+
+    @Provides
+    public SaveCurrentUser providesSaveCurrentUser(UserRepository repository) {
+        return new SaveCurrentUser(repository);
+    }
+
+    @Provides
+    public GetLocalUser providesGetLocalUser(UserRepository repository) {
+        return new GetLocalUser(repository);
+    }
+
+    @Provides
+    public UserRepository providesUserRepository(Context context, @Named("prefs") String prefsName) {
+        return new UserLocalRepository(context, prefsName);
+    }
+
+    @Provides
+    @Named("prefs")
+    public String providesPreferenceName() {
+        return "user_preference";
+    }
+
+}

app/src/main/java/br/org/cesar/discordtime/stickysessions/presentation/session/SessionContract.java

@@ -9,11 +9,13 @@ public interface SessionContract {
     interface Presenter {
         void attachView(SessionContract.View view);
         void detachView();
-        void onEnterSession(String sessionId);
         void onShareSession();
         void onAddNoteClicked();
         void addNewNote(String sessionId, String description);
         void onNoteWidgetClicked(Note note);
+        void onResume();
+        void currentUser(String userName);
+        void currentSession(String sessionId);
     }
 
     interface View {
@@ -28,5 +30,6 @@ interface View {
         void displayErrorInvalidNotes();
         void displayNoteContent(Note note);
         void addNoteToNoteList(Note note);
+        void showWidgetAddName();
     }
 }