Merge pull request #104 from CS2103AUG2016-T14-C2/V0.5rc-Implement-Re…

…curring-Tasks

Merge V0.5rc implement recurring tasks

docs/UserGuide.md

@@ -62,7 +62,7 @@ Format: `add TASK_NAME [s/START_DATE] [e/END_DATE] [l/LOCATION] [p/PRIORITY_LEVE
 > LOCATION | `Optional` Specifies the location where the task happens.
 > PRIORITY_LEVEL | `Optional` Specifies the priority level of the task.<br>`Accepts` values `low`, `medium`, `high`<br>`Defaults` to `???`
 > RECURRING_TYPE | `Optional` Specifies the recurring type of the task.<br>`Accepts` values `none`, `daily`, `weekly`, `monthly`, `yearly`<br>`Defaults` to `none`
-> NUMBER_OF_RECURRENCE | `Optional` Specifies the number of times the task recurrs. A value of 0 specifies a never-ending recurrence.<br>`Defaults` to `0`<br>`Ignored` if RECURRING_TYPE is `none`
+> NUMBER_OF_RECURRENCE | `Optional` Specifies the number of times the task recurrs. <br>`Defaults` to `1`<br>`Ignored` if RECURRING_TYPE is `none`
 > CATEGORY | `Optional` Specifies a custom category for the task. This can be used for keeping track of similar tasks.
 > DESCRIPTION | `Optional` Describes the task.
 

src/main/java/seedu/savvytasker/logic/commands/AddCommand.java

@@ -1,5 +1,8 @@
 package seedu.savvytasker.logic.commands;
 
+import java.util.Iterator;
+import java.util.LinkedList;
+
 import seedu.savvytasker.commons.core.EventsCenter;
 import seedu.savvytasker.commons.core.UnmodifiableObservableList;
 import seedu.savvytasker.commons.events.ui.JumpToListRequestEvent;
@@ -40,6 +43,7 @@ public class AddCommand extends ModelRequiringCommand {
     private final String description;
 
     private Task toAdd;
+    private LinkedList<Task> tasksAdded;
 
     //@@author A0139915W
     /**
@@ -57,26 +61,45 @@ public AddCommand(String taskName, InferredDate startDateTime, InferredDate endD
         this.numberOfRecurrence = numberOfRecurrence;
         this.category = category;
         this.description = description;
+        tasksAdded = new LinkedList<Task>();
     }
 
     private void createTask() {
         final boolean isArchived = false;   // all tasks are first added as active tasks
         final int taskId = 0;               // taskId to be assigned by ModelManager, leave as 0
+        final int groupId = 0;              // groupId to be assigned by ModelManager, leave as 0
 
-        this.toAdd = new Task(taskId, taskName, startDateTime, endDateTime,
+        this.toAdd = new Task(taskId, groupId, taskName, startDateTime, endDateTime,
                 location, priority, recurringType, numberOfRecurrence,
                 category, description, isArchived);
     }
+
+    private void addToListOfTasksAdded(Task... tasks) {
+        for (Task t : tasks) {
+            tasksAdded.add(t);
+        }
+    }
 
     @Override
     public CommandResult execute() {
         assert model != null;
         createTask();
 
         try {
-            Task taskAdded = model.addTask(toAdd);
+            Task taskAdded = null;
+            if (toAdd.getRecurringType() == RecurrenceType.None) {
+                // not a recurring task, add a single task
+                taskAdded = model.addTask(toAdd);
+                addToListOfTasksAdded(taskAdded);
+            } else {
+                // a recurring task, add a group of recurring tasks
+                LinkedList<Task> tasksAdded = model.addRecurringTask(toAdd);
+                taskAdded = tasksAdded.peekFirst();
+                addToListOfTasksAdded(tasksAdded.toArray(new Task[tasksAdded.size()]));
+            }
+
             int targetIndex = getIndexOfTask(taskAdded);
-            if (targetIndex > 0) {
+            if (targetIndex >= 0) {
                 EventsCenter.getInstance().post(new JumpToListRequestEvent(targetIndex));
             } else {
                 // GUI should never ever get here
@@ -119,7 +142,7 @@ public boolean canUndo() {
     @Override
     public boolean redo() {
         execute();
-        return false;
+        return true;
     }
 
     /**
@@ -128,20 +151,18 @@ public boolean redo() {
      */
     @Override
     public boolean undo() {
-
-        UnmodifiableObservableList<Task> lastShownList = model.getFilteredTaskListTask();
-
-        for (int i = 0; i < lastShownList.size(); i++) {
-            if (lastShownList.get(i) == toAdd){
-                ReadOnlyTask taskToDelete = lastShownList.get(i);
-                try {
-                    model.deleteTask(taskToDelete);
-                } catch (TaskNotFoundException e) {
-                    e.printStackTrace();
-                }
+        Iterator<Task> itr = tasksAdded.iterator();
+        while (itr.hasNext()) {
+            try {
+                model.deleteTask(itr.next());
+            } catch (TaskNotFoundException e) {
+                // do nothing.
             }
-        } 
-        return false;
+        }
+        // clears the list of tasks added.
+        // if redo is performed, the list will be populated again.
+        tasksAdded.clear(); 
+        return true;
     }
 
     /**

src/main/java/seedu/savvytasker/logic/commands/ModifyCommand.java

@@ -82,7 +82,7 @@ public CommandResult execute() {
             originalTask = (Task)taskToModify;
             Task taskModified = model.modifyTask(taskToModify, replacement);
             int targetIndex = getIndexOfTask(taskModified);
-            if (targetIndex > 0) {
+            if (targetIndex >= 0) {
                 EventsCenter.getInstance().post(new JumpToListRequestEvent(targetIndex));
             } else {
                 // GUI should never ever get here

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

@@ -1,5 +1,7 @@
 package seedu.savvytasker.model;
 
+import java.util.LinkedList;
+
 import seedu.savvytasker.commons.core.UnmodifiableObservableList;
 import seedu.savvytasker.model.alias.AliasSymbol;
 import seedu.savvytasker.model.alias.DuplicateSymbolKeywordException;
@@ -43,6 +45,13 @@ public interface Model {
      * @return Returns a Task if the add operation is successful, an exception is thrown otherwise.
      * */
     Task addTask(Task task) throws DuplicateTaskException, InvalidDateException;
+
+    /** Adds the given Task as a recurring task. The task's recurrence type must not be null.
+     * @throws {@link DuplicateTaskException} if a duplicate is found
+     * @throws {@link InvalidDateException} if the end date is earlier than the start date
+     * @return Returns the list of Tasks added if the add operation is successful, an exception is thrown otherwise.
+     * */
+    LinkedList<Task> addRecurringTask(Task task) throws DuplicateTaskException, InvalidDateException;
 
     /** Returns the filtered task list as an {@code UnmodifiableObservableList<ReadOnlyTask>} */
     UnmodifiableObservableList<ReadOnlyTask> getFilteredTaskList();

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

@@ -4,6 +4,7 @@
 import java.util.Comparator;
 import java.util.HashSet;
 import java.util.Iterator;
+import java.util.LinkedList;
 import java.util.List;
 import java.util.Set;
 import java.util.logging.Logger;
@@ -115,6 +116,14 @@ public synchronized Task addTask(Task t) throws DuplicateTaskException, InvalidD
         indicateSavvyTaskerChanged();
         return taskAdded;
     }
+
+    @Override
+    public synchronized LinkedList<Task> addRecurringTask(Task recurringTask) throws DuplicateTaskException, InvalidDateException {
+        LinkedList<Task> recurringTasks = savvyTasker.addRecurringTasks(recurringTask);
+        updateFilteredListToShowActive();
+        indicateSavvyTaskerChanged();
+        return recurringTasks;
+    }
     //@@author
 
     //@@author A0139916U

src/main/java/seedu/savvytasker/model/SavvyTasker.java

@@ -1,7 +1,11 @@
 package seedu.savvytasker.model;
 
+import java.util.Calendar;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.Date;
+import java.util.Iterator;
+import java.util.LinkedList;
 import java.util.List;
 import java.util.Objects;
 import java.util.stream.Collectors;
@@ -12,6 +16,7 @@
 import seedu.savvytasker.model.alias.DuplicateSymbolKeywordException;
 import seedu.savvytasker.model.alias.SymbolKeywordNotFoundException;
 import seedu.savvytasker.model.task.ReadOnlyTask;
+import seedu.savvytasker.model.task.RecurrenceType;
 import seedu.savvytasker.model.task.Task;
 import seedu.savvytasker.model.task.TaskList;
 import seedu.savvytasker.model.task.TaskList.DuplicateTaskException;
@@ -70,13 +75,130 @@ public void resetData(ReadOnlySavvyTasker newData) {
 
     /**
      * Adds a task to savvy tasker.
-     * @throws DuplicateTaskException if an equivalent task already exists.
-     * @throws InvalidDateException if the end date is earlier than the start date.
+     * @throws {@link DuplicateTaskException} if a duplicate is found
+     * @throws {@link InvalidDateException} if the end date is earlier than the start date
+     * @return Returns the task added if the operation succeeds, an exception is thrown otherwise.
      */
     public Task addTask(Task t) throws DuplicateTaskException, InvalidDateException {
         t.setId(tasks.getNextId());
         return tasks.add(t);
     }
+
+    /**
+     * Adds a group of recurring tasks to savvy tasker.
+     * @throws {@link DuplicateTaskException} if a duplicate is found
+     * @throws {@link InvalidDateException} if the end date is earlier than the start date
+     * @return Returns the list of recurring tasks if the operation succeeds, an exception is thrown otherwise
+     */
+    public LinkedList<Task> addRecurringTasks(Task recurringTask) throws DuplicateTaskException, InvalidDateException {
+        LinkedList<Task> tasksToAdd = 
+                createRecurringTasks(recurringTask, recurringTask.getRecurringType(), 
+                        recurringTask.getNumberOfRecurrence());
+        Iterator<Task> itr = tasksToAdd.iterator();
+
+        while(itr.hasNext()) {
+            // this will be an atomic operation
+            // guaranteed no duplicates
+            // if the start/end dates are invalid,
+            // the first task to be added will fail immediately, 
+            // subsequent tasks will not be added
+            tasks.add(itr.next()); 
+        }
+        return tasksToAdd;
+    }
+
+    /**
+     * Creates a list of recurring tasks to be added into savvy tasker.
+     * @param recurringTask the task that recurs
+     * @param recurringType the type of recurrence
+     * @param numberOfRecurrences the number of recurrences
+     * @return A list of tasks that represents a recurring task.
+     */
+    private LinkedList<Task> createRecurringTasks(Task recurringTask, RecurrenceType recurringType, int numberOfRecurrences) {
+        assert recurringTask.getRecurringType() != null;
+        assert recurringTask.getNumberOfRecurrence() > 0;
+
+        LinkedList<Task> listOfTasks = new LinkedList<Task>();
+        recurringTask.setGroupId(tasks.getNextGroupId());
+
+        for (int i = 0; i < numberOfRecurrences; ++i) {
+            Task t = recurringTask.clone();
+            t.setId(tasks.getNextId());
+            listOfTasks.add(setDatesForRecurringType(t, recurringType, i));
+        }
+
+        return listOfTasks;
+    }
+
+    /**
+     * Helper function for createRecurringTasks(). Sets the respective start/end datetime for the
+     * i-th recurring task to be added
+     * @param t The first recurring task
+     * @param recurringType the type of recurrence
+     * @param index the index of the loop
+     * @return A task with its respective datetime set.
+     */
+    private Task setDatesForRecurringType(Task t, RecurrenceType recurringType, int index) {
+        Date startDate = t.getStartDateTime();
+        Date endDate = t.getEndDateTime();
+        Calendar calendar = Calendar.getInstance();
+        switch (recurringType) {
+        case Daily: // add one day to the i-th task
+            if (startDate != null) {
+                calendar.setTime(startDate);
+                calendar.add(Calendar.DATE, 1 * index);
+                startDate = calendar.getTime();
+            }
+            if (endDate != null) {
+                calendar.setTime(endDate);
+                calendar.add(Calendar.DATE, 1 * index);
+                endDate = calendar.getTime();
+            }
+            break;
+        case Weekly:  // add 7 days to the i-th task
+            if (startDate != null) {
+                calendar.setTime(startDate);
+                calendar.add(Calendar.DATE, 7 * index);
+                startDate = calendar.getTime();
+            }
+            if (endDate != null) {
+                calendar.setTime(endDate);
+                calendar.add(Calendar.DATE, 7 * index);
+                endDate = calendar.getTime();
+            }
+            break;
+        case Monthly: // add 1 month to the i-th task
+            if (startDate != null) {
+                calendar.setTime(startDate);
+                calendar.add(Calendar.MONTH, 1 * index);
+                startDate = calendar.getTime();
+            }
+            if (endDate != null) {
+                calendar.setTime(endDate);
+                calendar.add(Calendar.MONTH, 1 * index);
+                endDate = calendar.getTime();
+            }
+            break;
+        case Yearly: // add 1 year to the i-th task
+            if (startDate != null) {
+                calendar.setTime(startDate);
+                calendar.add(Calendar.YEAR, 1 * index);
+                startDate = calendar.getTime();
+            }
+            if (endDate != null) {
+                calendar.setTime(endDate);
+                calendar.add(Calendar.YEAR, 1 * index);
+                endDate = calendar.getTime();
+            }
+            break;
+        case None:
+        default:
+            assert false; // should not come here
+        }
+        t.setStartDateTime(startDate);
+        t.setEndDateTime(endDate);
+        return t;
+    }
 
     /**
      * Removes a task from savvy tasker.

src/main/java/seedu/savvytasker/model/task/ReadOnlyTask.java

@@ -10,6 +10,7 @@
 public interface ReadOnlyTask {
 
     int getId();
+    int getGroupId();
     boolean isMarked();
     boolean isArchived();
     String getTaskName();
@@ -53,11 +54,7 @@ default String getAsText() {
                     .append(getLocation());
         }
         builder.append(" Priority: ")
-                .append(getPriority())
-                .append(" Recurring Type: ")
-                .append(getRecurringType())
-                .append(" Nr. Recurrence: ")
-                .append(getNumberOfRecurrence());
+                .append(getPriority());
         if (getCategory() != null && !getCategory().isEmpty()) {
             builder.append(" Category: ")
                     .append(getCategory());