Implement Calendar (#98)

* Add Calendar

Modify DateTime, TaskList to accomodate Calendar.
Add CalendarSelectorException.

src/main/java/spinbox/DateTime.java

@@ -4,6 +4,7 @@
 
 import java.text.DateFormat;
 import java.text.SimpleDateFormat;
+import java.util.Calendar;
 import java.util.Date;
 
 public class DateTime implements Comparable<DateTime> {
@@ -31,15 +32,44 @@ public Date getDateTime() {
         return dateTime;
     }
 
+    /**
+     * Return the day of the month.
+     * @return day of the month
+     */
+    public int getDayOfMonth() {
+        Calendar calendar = Calendar.getInstance();
+        calendar.setTime(dateTime);
+        return calendar.get(Calendar.DAY_OF_MONTH);
+    }
+
+    /**
+     * Return the day of the week.
+     * @return day of the week
+     */
+    public int getDayOfWeek() {
+        Calendar calendar = Calendar.getInstance();
+        calendar.setTime(dateTime);
+        return calendar.get(Calendar.DAY_OF_WEEK);
+    }
+
+    /**
+     * Return hour.
+     * @return hour
+     */
+    public int getHour() {
+        Calendar calendar = Calendar.getInstance();
+        calendar.setTime(dateTime);
+        return calendar.get(Calendar.HOUR_OF_DAY);
+    }
+
     /**
      * Converts the Date object back to the string version in the format of MM/dd/yyyy HH:mm
      * This can be reused to create an identical dateTime object.
      * @return String equivalent of Date object.
      */
     public String toString() {
         DateFormat dateFormat = new SimpleDateFormat("MM/dd/yyyy HH:mm");
-        String dateString = dateFormat.format(dateTime);
-        return dateString;
+        return dateFormat.format(dateTime);
     }
 
     public boolean before(DateTime dateTime) {
@@ -59,5 +89,55 @@ public int compareTo(DateTime dateTimeTwo) {
         return this.getDateTime().compareTo(dateTimeTwo.getDateTime());
     }
 
+    /**
+     * Return another DateTime with date
+     * set as start of the week relative to this DateTime.
+     * @return start of the week
+     */
+    public DateTime getStartOfTheWeek() {
+        Calendar calendar = Calendar.getInstance();
+        calendar.setTime(dateTime);
+        while (calendar.get(Calendar.DAY_OF_WEEK) != Calendar.SUNDAY) {
+            calendar.add(Calendar.DATE, -1);
+        }
+        return new DateTime(calendar.getTime());
+    }
+
+    /**
+     * Return another DateTime with date
+     * set as end of the week relative to this DateTime.
+     * @return end of the week
+     */
+    public DateTime getEndOfTheWeek() {
+        Calendar calendar = Calendar.getInstance();
+        calendar.setTime(dateTime);
+        while (calendar.get(Calendar.DAY_OF_WEEK) != Calendar.SATURDAY) {
+            calendar.add(Calendar.DATE, 1);
+        }
+        return new DateTime(calendar.getTime());
+    }
 
+    /**
+     * Return another DateTime with date
+     * set as start of the month relative to this DateTime.
+     * @return start of the month
+     */
+    public DateTime getStartOfTheMonth() {
+        Calendar calendar = Calendar.getInstance();
+        calendar.setTime(dateTime);
+        calendar.set(Calendar.DAY_OF_MONTH, 1);
+        return new DateTime(calendar.getTime());
+    }
+
+    /**
+     * Return another DateTime with date
+     * set as end of the month relative to this DateTime.
+     * @return end of the month
+     */
+    public DateTime getEndOfTheMonth() {
+        Calendar calendar = Calendar.getInstance();
+        calendar.setTime(dateTime);
+        calendar.set(Calendar.DAY_OF_MONTH, calendar.getActualMaximum(Calendar.DAY_OF_MONTH));
+        return new DateTime(calendar.getTime());
+    }
 }

src/main/java/spinbox/containers/lists/TaskList.java

@@ -91,7 +91,29 @@ public List<String> viewList() {
         List<String> output = new ArrayList<>();
         output.add("Here are the tasks in your module:");
         for (int i = 0; i < list.size(); i++) {
-            output.add((Integer.toString(i + 1) + ". " + list.get(i).toString()));
+            output.add(((i + 1) + ". " + list.get(i).toString()));
+        }
+        return output;
+    }
+
+    /**
+     * Return list of task that overlaps with start and end interval.
+     * @param startInterval start of the interval.
+     * @param endInterval end of the interval.
+     * @return list of task
+     */
+    public List<String> viewListInterval(DateTime startInterval, DateTime endInterval) {
+        Task currentTask;
+        List<String> output = new ArrayList<>();
+        output.add("Here are the task in your module:");
+        for (int i = 0; i < list.size(); i++) {
+            currentTask = list.get(i);
+            if (currentTask.isSchedulable()) {
+                Schedulable task = (Schedulable) currentTask;
+                if (task.isOverlapping(startInterval, endInterval)) {
+                    output.add(((i + 1) + ". " + task.toString()));
+                }
+            }
         }
         return output;
     }

src/main/java/spinbox/entities/Calendar.java

@@ -0,0 +1,43 @@
+package spinbox.entities;
+
+import spinbox.DateTime;
+import spinbox.containers.lists.TaskList;
+import spinbox.exceptions.CalendarSelectorException;
+
+import java.util.List;
+
+public class Calendar {
+    private static final String MIDNIGHT = " 00:00";
+    private static final String BEFORE_MIDNIGHT = " 23:59";
+    DateTime startDate;
+    DateTime endDate;
+    int modifier;
+
+    public Calendar(int modifier, String date) throws CalendarSelectorException {
+        this.modifier = modifier;
+        setDates(date);
+    }
+
+    private void setDates(String date) throws CalendarSelectorException {
+        switch (modifier) {
+        case 1:
+            startDate = new DateTime(date + MIDNIGHT);
+            endDate = new DateTime(date + BEFORE_MIDNIGHT);
+            break;
+        case 2:
+            startDate = new DateTime(date + MIDNIGHT).getStartOfTheWeek();
+            endDate = new DateTime(date + BEFORE_MIDNIGHT).getEndOfTheWeek();
+            break;
+        case 3:
+            startDate = new DateTime(date + MIDNIGHT).getStartOfTheMonth();
+            endDate = new DateTime(date + BEFORE_MIDNIGHT).getEndOfTheMonth();
+            break;
+        default:
+            throw new CalendarSelectorException();
+        }
+    }
+
+    public List<String> tasksInCalendar(TaskList taskList) {
+        return taskList.viewListInterval(startDate, endDate);
+    }
+}

src/main/java/spinbox/exceptions/CalendarSelectorException.java

@@ -0,0 +1,10 @@
+package spinbox.exceptions;
+
+public class CalendarSelectorException extends SpinBoxException {
+    private static final String ERROR_MESSAGE = "Error: Please supply 1, 2, 3 to corresponding"
+            + " to day, month or year for calendar selection";
+
+    public CalendarSelectorException() {
+        super(ERROR_MESSAGE);
+    }
+}

src/test/java/DateTimeTest.java

@@ -2,12 +2,14 @@
 import spinbox.exceptions.SpinBoxException;
 import org.junit.jupiter.api.Test;
 
+import java.time.DayOfWeek;
+
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
 public class DateTimeTest {
 
     @Test
-    public void correctDateInputShouldCreateReusableString() throws SpinBoxException {
+    public void dateTimeCreation_variousDateTimeString_successfulCreationAndExpectedStringOutput() {
         DateTime test = new DateTime("05/02/2020 12:00");
         assertEquals("05/02/2020 12:00", test.toString());
 
@@ -23,7 +25,7 @@ public void correctDateInputShouldCreateReusableString() throws SpinBoxException
     }
 
     @Test
-    public void parseDifferentDateFormattedString() throws SpinBoxException {
+    public void dateTimeCreation_differentlyFormattedDateTimeString_successfulCreationAndExpectedStringOutput() {
         DateTime test = new DateTime("the day before 12/16/2019 4pm");
         assertEquals("12/15/2019 16:00", test.toString());
 
@@ -38,4 +40,51 @@ public void parseDifferentDateFormattedString() throws SpinBoxException {
         assertEquals("12/25/2019 06:00", santaVacationStartDate.toString());
         assertEquals("12/24/2020 23:59", santaVacationEndDate.toString());
     }
+
+    @Test
+    public void getDayOfMonth_DateTimeString_expectedDay() {
+        DateTime test = new DateTime("10/16/2019 12:33");
+        assertEquals(16, test.getDayOfMonth());
+    }
+
+    @Test
+    public void getDayOfWeek_DateTimeString_expectedDay() {
+        DateTime test = new DateTime("10/16/2019 12:33");
+        assertEquals(4, test.getDayOfWeek());
+    }
+
+    @Test
+    public void getHour_DateTimeString_expectedHour() {
+        String date = "10/16/2019 12:33";
+        DateTime test = new DateTime(date);
+        assertEquals(12, test.getHour());
+    }
+
+    @Test
+    public void getStartOfTheWeek_DateTimeString_expectedDateTimeString() {
+        String date = "10/16/2019";
+        DateTime test = new DateTime(date + " 00:00");
+        assertEquals("10/13/2019 00:00", test.getStartOfTheWeek().toString());
+    }
+
+    @Test
+    public void getEndOfTheWeek_DateTimeString_expectedDateTimeString() {
+        String date = "10/16/2019";
+        DateTime test = new DateTime(date + " 23:59");
+        assertEquals("10/19/2019 23:59", test.getEndOfTheWeek().toString());
+    }
+
+    @Test
+    public void getStartOfTheMonth_DateTimeString_expectedDateTimeString() {
+        String date = "10/16/2019";
+        DateTime test = new DateTime(date + " 00:00");
+        assertEquals("10/01/2019 00:00", test.getStartOfTheMonth().toString());
+    }
+
+    @Test
+    public void getEndOfTheMonth_DateTimeString_expectedDateTimeString() {
+        String date = "10/16/2019";
+        DateTime test = new DateTime(date + " 23:59");
+        assertEquals("10/31/2019 23:59", test.getEndOfTheMonth().toString());
+    }
 }