Create different task type subclasses to align towards the OOP standard

src/main/java/muller/parser/Parser.java

@@ -9,6 +9,7 @@
 import muller.command.MarkCommand;
 import muller.command.MullerException;
 import muller.command.OnCommand;
+import muller.command.RemindCommand;
 import muller.command.UnmarkCommand;
 
 /**
@@ -30,12 +31,14 @@ public Command parse(String fullCommand) throws MullerException {
         String[] inputs = fullCommand.split(" ", 2);
 
         // Programmer-level assumption: inputs should always have at least one element (the command itself)
-        assert inputs.length > 0 : "Command should have at least one token";
+        assert inputs.length > 0 : "Command should not be empty";
         String commandWord = inputs[0].toLowerCase();
 
         switch (commandWord) {
         case "bye":
             return new ExitCommand();
+        case "remind":
+            return new RemindCommand(inputs);
         case "list":
             return new ListCommand();
         case "mark":

src/main/java/muller/storage/Storage.java

@@ -10,14 +10,18 @@
 import java.util.ArrayList;
 
 import muller.command.MullerException;
+import muller.task.DeadlineTask;
+import muller.task.EventTask;
 import muller.task.Task;
 import muller.task.TaskList;
+import muller.task.TodoTask;
 
 /**
  * Handles the loading and saving of tasks to and from a file.
  */
 public class Storage {
     private String filePath;
+
     /**
      * Constructs a Storage object with the specified file path.
      *
@@ -26,6 +30,7 @@ public class Storage {
     public Storage(String filePath) {
         this.filePath = filePath;
     }
+
     /**
      * Loads tasks from the specified file.
      *
@@ -86,25 +91,39 @@ public void saveTasks(TaskList tasks) throws MullerException {
      * Parses a line of text from the file into a Task object.
      *
      * @param parts The components of the task read from the file.
-     * @return The Task object parsed from the file.
+     * @return The specific Task object (TodoTask, DeadlineTask, EventTask) parsed from the file.
      * @throws MullerException If there is an issue parsing the task.
      */
     private Task parseTask(String[] parts) throws MullerException {
-        String type = parts[0];
-        boolean isDone = parts[1].equals("1");
-        String name = parts[2];
-        Task task = new Task(name);
-        task.setType(type);
-        task.markAsDone(isDone);
+        String type = parts[0].trim(); // Get task type: [T], [D], [E]
+        boolean isDone = parts[1].equals("1"); // Done status
+        String name = parts[2].trim(); // Task name
 
-        if (type.equals("D") && parts.length >= 4) {
-            LocalDate date = LocalDate.parse(parts[3], Task.INPUT_DATE_FORMATTER);
-            task.setDate(date);
-        } else if (type.equals("E") && parts.length >= 5) {
-            LocalDate startDate = LocalDate.parse(parts[3], Task.INPUT_DATE_FORMATTER);
-            LocalDate endDate = LocalDate.parse(parts[4], Task.INPUT_DATE_FORMATTER);
-            task.setDateRange(startDate, endDate);
+        Task task;
+        switch (type) {
+        case "T":
+            task = new TodoTask(name);
+            break;
+        case "D":
+            if (parts.length < 4) {
+                throw new MullerException("Deadline task is missing date information.");
+            }
+            LocalDate deadline = LocalDate.parse(parts[3].trim(), Task.OUTPUT_DATE_FORMATTER);
+            task = new DeadlineTask(name, deadline);
+            break;
+        case "E":
+            if (parts.length < 5) {
+                throw new MullerException("Event task is missing start and/or end date information.");
+            }
+            LocalDate startDate = LocalDate.parse(parts[3].trim(), Task.OUTPUT_DATE_FORMATTER);
+            LocalDate endDate = LocalDate.parse(parts[4].trim(), Task.OUTPUT_DATE_FORMATTER);
+            task = new EventTask(name, startDate, endDate);
+            break;
+        default:
+            throw new MullerException("Unknown task type found in file.");
         }
+
         return task;
     }
 }
+

src/main/java/muller/task/DeadlineTask.java

@@ -1,4 +1,72 @@
 package muller.task;
 
-public class DeadlineTask {
+import java.time.LocalDate;
+
+/**
+ * Represents a task that has a deadline.
+ */
+public class DeadlineTask extends Task {
+    private LocalDate deadline;
+    /**
+     * Constructs a DeadlineTask object with the specified name and deadline date.
+     *
+     * @param name     The name of the deadline task.
+     * @param deadline The deadline date of the task.
+     */
+    public DeadlineTask(String name, LocalDate deadline) {
+        super(name);
+        this.deadline = deadline;
+        this.type = "[D]";
+    }
+
+    /**
+     * Returns the deadline date of the task.
+     *
+     * @return The deadline date.
+     */
+    public LocalDate getDeadline() {
+        return deadline;
+    }
+
+    /**
+     * Checks if the task occurs on a specified date.
+     *
+     * @param date The date to check.
+     * @return True if the task's deadline is on the specified date, false otherwise.
+     */
+    @Override
+    public boolean isOnDate(LocalDate date) {
+        return this.deadline.equals(date);
+    }
+
+    /**
+     * Checks if the task is due within the next 3 days.
+     *
+     * @return True if the deadline is within the next 3 days, false otherwise.
+     */
+    @Override
+    public boolean isDueSoon() {
+        return deadline.isBefore(LocalDate.now().plusDays(3)) && deadline.isAfter(LocalDate.now());
+    }
+
+    /**
+     * Converts the DeadlineTask to a string format suitable for saving to a file.
+     *
+     * @return The string representation of the DeadlineTask for saving.
+     */
+    @Override
+    public String convertToFileString() {
+        return "D | " + (isDone() ? "1" : "0") + " | " + getName() + " | " + deadline.format(OUTPUT_DATE_FORMATTER);
+    }
+
+    /**
+     * Returns a string representation of the task, including its deadline.
+     *
+     * @return A string representing the task and its deadline.
+     */
+    @Override
+    public String toString() {
+        return this.type + getDoneIcon() + " " + getName() + " (by: " + deadline.format(OUTPUT_DATE_FORMATTER) + ")";
+    }
 }
+

src/main/java/muller/task/EventTask.java

@@ -1,4 +1,87 @@
 package muller.task;
 
-public class EventTask {
+import java.time.LocalDate;
+
+/**
+ * Represents a task that occurs over a range of dates.
+ */
+public class EventTask extends Task {
+    private LocalDate startDate;
+    private LocalDate endDate;
+
+    /**
+     * Constructs an EventTask object with the specified name, start date, and end date.
+     *
+     * @param name      The name of the event task.
+     * @param startDate The start date of the event.
+     * @param endDate   The end date of the event.
+     */
+    public EventTask(String name, LocalDate startDate, LocalDate endDate) {
+        super(name);
+        this.startDate = startDate;
+        this.endDate = endDate;
+        this.type = "[E]";
+    }
+
+    /**
+     * Checks if the task occurs on a specified date.
+     *
+     * @param date The date to check.
+     * @return True if the date is within the event's start and end dates, false otherwise.
+     */
+    @Override
+    public boolean isOnDate(LocalDate date) {
+        return !date.isBefore(startDate) && !date.isAfter(endDate);
+    }
+
+    /**
+     * Checks if the event starts within the next 3 days.
+     *
+     * @return True if the start date is within the next 3 days, false otherwise.
+     */
+    @Override
+    public boolean isDueSoon() {
+        return startDate.isBefore(LocalDate.now().plusDays(3)) && startDate.isAfter(LocalDate.now());
+    }
+
+    /**
+     * Returns the start date of the task.
+     *
+     * @return The event start date.
+     */
+    public LocalDate getStartDate() {
+        return startDate;
+    }
+
+    /**
+     * Returns the start date of the task.
+     *
+     * @return The event start date.
+     */
+    public LocalDate getEndDate() {
+        return endDate;
+    }
+
+    /**
+     * Converts the EventTask to a string format suitable for saving to a file.
+     *
+     * @return The string representation of the EventTask for saving.
+     */
+    @Override
+    public String convertToFileString() {
+        return "E | " + (isDone() ? "1" : "0") + " | " + getName() + " | " + startDate.format(OUTPUT_DATE_FORMATTER)
+                + " | " + endDate.format(OUTPUT_DATE_FORMATTER);
+    }
+
+    /**
+     * Returns a string representation of the task, including its start and end dates.
+     *
+     * @return A string representing the task and its date range.
+     */
+    @Override
+    public String toString() {
+        return this.type + getDoneIcon() + " " + getName() + " (from: " + startDate.format(OUTPUT_DATE_FORMATTER)
+                + " to: " + endDate.format(OUTPUT_DATE_FORMATTER) + ")";
+    }
 }
+