Google Calendar Integration (#192)

* Maven Google Calendar SDK

* SyncManager

* Create new classes

* Sync command

* Add more gradle dependencies

* Create Sync & SyncProvider interfaces

* ModelManager supports Sync

* Sync methods in Model

* Add Sync to parser

* SyncManager

* Sync provider Google

* Google stuff

* Revert bad merge change

* Basic event adding hooks workings

* tag code

* CRUD support

* Cleanup

* Sync on/off is now persisted using credential file

* Multithreading and concurrency

* Multithreading and concurrency support in SyncProvider made it trival to support adding add tasks when Sync is turned on

* Small cleanup

* Add mockito dependency

* SyncManagerTests

* Testing sync on/off

* Remove sync on

* tag syncmanagertest

* Simple testing in GoogleTests

* Add invalid sync

* deleteCalendadrMethod

* Much more Google calendar testing

* test sync on too

* tag code

* Add comments

build.gradle

@@ -37,6 +37,11 @@ allprojects {
         monocleVersion = '1.8.0_20'
         nattyVersion = '0.12'
 		reflectionsVersion = '0.9.10'
+		googleCalendarVersion = 'v3-rev220-1.22.0'
+		googleHttpVersion = '1.21.0'
+		googleOauthVersion = '1.21.0'
+		mockitoVersion = '1.+'
+
 
         libDir = 'lib'
     }
@@ -56,6 +61,10 @@ allprojects {
         compile "com.google.guava:guava:$guavaVersion"
         compile "com.joestelmach:natty:$nattyVersion"
 		compile "org.reflections:reflections:$reflectionsVersion"
+		compile "com.google.apis:google-api-services-calendar:$googleCalendarVersion"
+		compile "com.google.http-client:google-http-client-jackson2:$googleHttpVersion"
+		compile "com.google.oauth-client:google-oauth-client-jetty:$googleOauthVersion"
+		compile "org.mockito:mockito-core:$mockitoVersion"
 
         testCompile "junit:junit:$junitVersion"
         testCompile "org.testfx:testfx-core:$testFxVersion"

src/main/java/seedu/agendum/logic/commands/SyncCommand.java

@@ -0,0 +1,60 @@
+package seedu.agendum.logic.commands;
+
+import seedu.agendum.commons.exceptions.IllegalValueException;
+
+public class SyncCommand extends Command {
+    // COMMAND_WORD, COMMAND_FORMAT, COMMAND_DESCRIPTION are for display in help window
+    public static final String COMMAND_WORD = "sync";
+    private static final String COMMAND_FORMAT = "sync <on/off>";
+    private static final String COMMAND_DESCRIPTION = "Turn syncing on or off";
+    private static final String MESSAGE_USAGE = COMMAND_WORD + "- "
+            + COMMAND_DESCRIPTION;
+
+    public static final String SYNC_ON_MESSAGE = "Google Calendar Sync is on";
+    public static final String SYNC_OFF_MESSAGE = "Google Calendar Sync is off";
+
+    public static final String MESSAGE_WRONG_OPTION = "Invalid option for sync.";
+
+    private boolean syncOption;
+
+    //@@author A0003878Y
+    /**
+     * Convenience constructor using name
+     *
+     * @throws IllegalValueException if any of the raw values are invalid
+     */
+    public SyncCommand(String option) throws IllegalValueException {
+
+        if (option.trim().equalsIgnoreCase("on")) {
+            syncOption = true;
+        } else if (option.trim().equalsIgnoreCase("off")) {
+            syncOption = false;
+        } else {
+            throw new IllegalValueException(MESSAGE_WRONG_OPTION);
+        }
+    }
+
+    @Override
+    public CommandResult execute() {
+        if (syncOption) {
+            model.activateModelSyncing();
+            return new CommandResult(SYNC_ON_MESSAGE);
+        } else {
+            model.deactivateModelSyncing();
+            return new CommandResult(SYNC_OFF_MESSAGE);
+        }
+    }
+
+    //@@author
+    public static String getName() {
+        return COMMAND_WORD;
+    }
+
+    public static String getFormat() {
+        return COMMAND_FORMAT;
+    }
+
+    public static String getDescription() {
+        return COMMAND_DESCRIPTION;
+    }
+}

src/main/java/seedu/agendum/logic/parser/Parser.java

@@ -122,6 +122,10 @@ public Command parseCommand(String userInput) {
         case LoadCommand.COMMAND_WORD :
             return new LoadCommand(arguments);
 
+        case SyncCommand.COMMAND_WORD: {
+            return prepareSync(arguments);
+        }
+
         default:
             //@@author A0003878Y
             Optional<String> alternativeCommand = EditDistanceCalculator.closestCommandMatch(commandWord);
@@ -413,7 +417,8 @@ private Set<Integer> parseIndexes(String args) {
         }
 
         return taskIds;
-    }    
+    }
+
     //@@author
 
     /**
@@ -435,4 +440,20 @@ private Command prepareFind(String args) {
         return new FindCommand(keywordSet);
     }
 
+    //@@author A0003878Y
+    /**
+     * Parses arugments in the context of the sync command.
+     *
+     * @param args full command args string
+     * @return the prepared command
+     */
+    private Command prepareSync(String args) {
+        try {
+            return new SyncCommand(args);
+        } catch (IllegalValueException ive) {
+            return new IncorrectCommand(ive.getMessage());
+        }
+    }
+
+    //@@author
 }

src/main/java/seedu/agendum/model/Model.java

@@ -66,4 +66,10 @@ void unmarkTasks(List<ReadOnlyTask> targets)
     /** Updates the current todolist to the loaded data**/
     void handleLoadDataCompleteEvent(LoadDataCompleteEvent event);
 
+    /** Turns on model syncing using to a thirds party syncing provider **/
+    void activateModelSyncing();
+
+    /** Turns off model syncing **/
+    void deactivateModelSyncing();
+
 }

src/main/java/seedu/agendum/model/ModelManager.java

@@ -22,6 +22,9 @@
 import java.util.logging.Logger;
 
 import com.google.common.eventbus.Subscribe;
+import seedu.agendum.sync.Sync;
+import seedu.agendum.sync.SyncManager;
+import seedu.agendum.sync.SyncProviderGoogle;
 
 /**
  * Represents the in-memory model of the to do list data.
@@ -35,6 +38,8 @@ public class ModelManager extends ComponentManager implements Model {
     private final FilteredList<Task> filteredTasks;
     private final SortedList<Task> sortedTasks;
 
+    private final SyncManager syncManager;
+
     //@@author A0133367E
     /**
      * Signals that an operation to remove a list from the stack of previous lists would fail
@@ -59,6 +64,8 @@ public ModelManager(ToDoList src, UserPrefs userPrefs) {
         sortedTasks = filteredTasks.sorted();
         previousLists = new Stack<ToDoList>();
         backupCurrentToDoList();
+
+        syncManager = new SyncManager(new SyncProviderGoogle());
     }
 
     public ModelManager() {
@@ -71,6 +78,8 @@ public ModelManager(ReadOnlyToDoList initialData) {
         sortedTasks = filteredTasks.sorted();
         previousLists = new Stack<ToDoList>();
         backupCurrentToDoList();
+
+        syncManager = new SyncManager(new SyncProviderGoogle());
     }
 
     //@@author A0133367E
@@ -111,6 +120,9 @@ private void indicateLoadDataRequest(String location) {
     public synchronized void deleteTasks(List<ReadOnlyTask> targets) throws TaskNotFoundException {
         for (ReadOnlyTask target: targets) {
             toDoList.removeTask(target);
+
+            // Delete tasks in sync manager
+            syncManager.deleteEvent((Task) target);
         }
 
         logger.fine("[MODEL] --- successfully deleted all specified targets from the to-do list");
@@ -126,6 +138,8 @@ public synchronized void addTask(Task task) throws UniqueTaskList.DuplicateTaskE
         backupCurrentToDoList();
         updateFilteredListToShowAll();
         indicateToDoListChanged();
+
+        syncManager.addNewEvent(task);
     }
 
     @Override
@@ -137,6 +151,10 @@ public synchronized void updateTask(ReadOnlyTask target, Task updatedTask)
         backupCurrentToDoList();
         updateFilteredListToShowAll();
         indicateToDoListChanged();
+
+        // Delete old task and add new task
+        syncManager.deleteEvent((Task) target);
+        syncManager.addNewEvent(updatedTask);
     }
 
     @Override
@@ -226,8 +244,28 @@ public synchronized void loadFromLocation(String location) {
         indicateChangeSaveLocation(location);
         indicateLoadDataRequest(location);
     }
+    //@@author A0003878Y
+
+    //=========== Sync Methods ===============================================================================
+
+    @Override
+    public void activateModelSyncing() {
+        if (syncManager.getSyncStatus() != Sync.SyncStatus.RUNNING) {
+            syncManager.startSyncing();
+
+            // Add all current events into sync provider
+            toDoList.getTasks().forEach(syncManager::addNewEvent);
+        }
+    }
+
+    @Override
+    public void deactivateModelSyncing() {
+        if (syncManager.getSyncStatus() != Sync.SyncStatus.NOTRUNNING) {
+            syncManager.stopSyncing();
+        }
+    }
+
     //@@author
-
     //=========== Filtered Task List Accessors ===============================================================
 
     @Override

src/main/java/seedu/agendum/sync/Sync.java

@@ -0,0 +1,30 @@
+package seedu.agendum.sync;
+
+import seedu.agendum.model.task.Task;
+
+//@@author A0003878Y
+public interface Sync {
+
+    /** Enum used to persist SyncManager status **/
+    enum SyncStatus {
+        RUNNING, NOTRUNNING
+    }
+
+    /** Retrieve sync manager sync status **/
+    SyncStatus getSyncStatus();
+
+    /** Sets sync manager sync status **/
+    void setSyncStatus(SyncStatus syncStatus);
+
+    /** Turn on syncing **/
+    void startSyncing();
+
+    /** Turn off syncing **/
+    void stopSyncing();
+
+    /** Add Task to sync provider **/
+    void addNewEvent(Task task);
+
+    /** Remove task from sync provider **/
+    void deleteEvent(Task task);
+}

src/main/java/seedu/agendum/sync/SyncManager.java

@@ -0,0 +1,58 @@
+package seedu.agendum.sync;
+
+import seedu.agendum.commons.core.ComponentManager;
+import seedu.agendum.commons.core.LogsCenter;
+import seedu.agendum.model.task.Task;
+
+import java.util.logging.Logger;
+
+//@@author A0003878Y
+public class SyncManager extends ComponentManager implements Sync {
+    private final Logger logger = LogsCenter.getLogger(SyncManager.class);
+    private SyncStatus syncStatus = SyncStatus.NOTRUNNING;
+
+    private final SyncProvider syncProvider;
+
+    public SyncManager(SyncProvider syncProvider) {
+        this.syncProvider = syncProvider;
+        this.syncProvider.setManager(this);
+
+        syncProvider.startIfNeeded();
+    }
+
+    @Override
+    public SyncStatus getSyncStatus() {
+        return syncStatus;
+    }
+
+    @Override
+    public void setSyncStatus(SyncStatus syncStatus) {
+        this.syncStatus = syncStatus;
+    }
+
+    @Override
+    public void startSyncing() {
+        syncProvider.start();
+    }
+
+    @Override
+    public void stopSyncing() {
+        syncProvider.stop();
+    }
+
+    @Override
+    public void addNewEvent(Task task) {
+        if (syncStatus == SyncStatus.RUNNING) {
+            if (task.getStartDateTime().isPresent() && task.getEndDateTime().isPresent()) {
+                syncProvider.addNewEvent(task);
+            }
+        }
+    }
+
+    @Override
+    public void deleteEvent(Task task) {
+        if (syncStatus == SyncStatus.RUNNING) {
+            syncProvider.deleteEvent(task);
+        }
+    }
+}

src/main/java/seedu/agendum/sync/SyncProvider.java

@@ -0,0 +1,31 @@
+package seedu.agendum.sync;
+
+import seedu.agendum.model.task.Task;
+
+//@@author A0003878Y
+public abstract class SyncProvider {
+
+    /** Sync provider's keep a reference to the manager so that they can set it's
+     * sync status **/
+    protected Sync syncManager;
+
+    /** Start sync provider and perform initialization **/
+    public abstract void start();
+
+    /** Start sync provider if it needs to be started **/
+    public abstract void startIfNeeded();
+
+    /** Stop sync provider and perform cleanup **/
+    public abstract void stop();
+
+    /** Add event into sync provider **/
+    public abstract void addNewEvent(Task task);
+
+    /** Delete event from sync provider **/
+    public abstract void deleteEvent(Task task);
+
+    /** Set sync provider's sync manager **/
+    public void setManager(Sync syncManager) {
+        this.syncManager = syncManager;
+    }
+}