From a05464fcf0108070fe05a77c24c723ff7581e863 Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Tue, 24 Aug 2021 14:42:36 +0800
Subject: [PATCH 01/25] Level 0: Greet

---
 src/main/java/Greet.java | 6 ++++++
 1 file changed, 6 insertions(+)
 create mode 100644 src/main/java/Greet.java

diff --git a/src/main/java/Greet.java b/src/main/java/Greet.java
new file mode 100644
index 000000000..a2ee65191
--- /dev/null
+++ b/src/main/java/Greet.java
@@ -0,0 +1,6 @@
+public class Greet {
+    public static void main (String[] args) {
+        System.out.println("Hello! I'm Duke\n" + "What can I do for you?");
+        System.out.println("Bye. Hope to see you again soon!");
+    }
+}
\ No newline at end of file

From efd9e5bc401cb761aa42cc5f85d28ca235fcf735 Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Thu, 26 Aug 2021 00:25:38 +0800
Subject: [PATCH 02/25] Level-1

---
 src/main/java/Greet.java | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/src/main/java/Greet.java b/src/main/java/Greet.java
index a2ee65191..60f8ea3f4 100644
--- a/src/main/java/Greet.java
+++ b/src/main/java/Greet.java
@@ -1,6 +1,21 @@
+import java.util.Arrays;
+import java.util.Scanner;
+
 public class Greet {
     public static void main (String[] args) {
-        System.out.println("Hello! I'm Duke\n" + "What can I do for you?");
+        System.out.println("Hello! I'm Duke");
+        String line;
+        Scanner in = new Scanner(System.in);
+        System.out.println("What can I do for you?");
+        line = in.nextLine();
+        boolean bool1 = false;
+        while (!bool1) {
+            System.out.println(line);
+            line = in.nextLine();
+            if (line.contains("bye")) {
+                bool1 = true;
+            }
+        }
         System.out.println("Bye. Hope to see you again soon!");
     }
 }
\ No newline at end of file

From 99d6469029ae643e13f890c148c98798fe6edbb4 Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Thu, 26 Aug 2021 00:42:33 +0800
Subject: [PATCH 03/25] Level-2

---
 src/main/java/Greet.java | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/main/java/Greet.java b/src/main/java/Greet.java
index 60f8ea3f4..e056d41cf 100644
--- a/src/main/java/Greet.java
+++ b/src/main/java/Greet.java
@@ -3,6 +3,8 @@
 
 public class Greet {
     public static void main (String[] args) {
+        String[] tasks = new String[100];
+        int ntasks = 0;
         System.out.println("Hello! I'm Duke");
         String line;
         Scanner in = new Scanner(System.in);
@@ -10,8 +12,15 @@ public static void main (String[] args) {
         line = in.nextLine();
         boolean bool1 = false;
         while (!bool1) {
-            System.out.println(line);
+            System.out.println("added: " + line);
+            tasks[ntasks]= line;
+            ntasks += 1;
             line = in.nextLine();
+            if (line.equals("list")) {
+                for (int i = 0; i < ntasks; i += 1) {
+                    System.out.println((i+1) + ". " + tasks[i]);
+                }
+            }
             if (line.contains("bye")) {
                 bool1 = true;
             }

From 1814bd1edf5636476a63a7c6d0167a9fa4dc6857 Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Thu, 26 Aug 2021 10:28:33 +0800
Subject: [PATCH 04/25] Level-3

---
 src/main/java/Greet.java | 27 ++++++++++++++++-----------
 src/main/java/Task.java  | 21 +++++++++++++++++++++
 2 files changed, 37 insertions(+), 11 deletions(-)
 create mode 100644 src/main/java/Task.java

diff --git a/src/main/java/Greet.java b/src/main/java/Greet.java
index e056d41cf..c83fac83e 100644
--- a/src/main/java/Greet.java
+++ b/src/main/java/Greet.java
@@ -2,28 +2,33 @@
 import java.util.Scanner;
 
 public class Greet {
-    public static void main (String[] args) {
-        String[] tasks = new String[100];
+    public static void main(String[] args) {
+        Task[] tasks = new Task[100];
         int ntasks = 0;
         System.out.println("Hello! I'm Duke");
         String line;
         Scanner in = new Scanner(System.in);
         System.out.println("What can I do for you?");
         line = in.nextLine();
-        boolean bool1 = false;
-        while (!bool1) {
-            System.out.println("added: " + line);
-            tasks[ntasks]= line;
-            ntasks += 1;
-            line = in.nextLine();
+        while (!line.equals("bye")) {
             if (line.equals("list")) {
                 for (int i = 0; i < ntasks; i += 1) {
-                    System.out.println((i+1) + ". " + tasks[i]);
+                    System.out.println((i + 1) + ".[" + tasks[i].getStatusIcon() + "] " + tasks[i].getDescription());
                 }
             }
-            if (line.contains("bye")) {
-                bool1 = true;
+            else if (line.contains("done")) {
+                String[] splitTask = line.split(" ");
+                int index = Integer.parseInt(splitTask[1]) - 1;
+                tasks[index].setDone();
+                System.out.println("Nice! I've marked this task as done:");
+                System.out.println("[" + tasks[index].getStatusIcon() + "] " + tasks[index].getDescription());
+            }
+            else {
+                tasks[ntasks] = new Task(line);
+                ntasks += 1;
+                System.out.println("added: " + line);
             }
+            line = in.nextLine();
         }
         System.out.println("Bye. Hope to see you again soon!");
     }
diff --git a/src/main/java/Task.java b/src/main/java/Task.java
new file mode 100644
index 000000000..7bca99c9b
--- /dev/null
+++ b/src/main/java/Task.java
@@ -0,0 +1,21 @@
+public class Task {
+    protected String description;
+    protected boolean isDone;
+
+    public Task(String description) {
+        this.description = description;
+        this.isDone = false;
+    }
+
+    public String getStatusIcon() {
+        return (isDone ? "X" : " "); // mark done task with X
+    }
+
+    public String getDescription() {
+        return description;
+    }
+
+    public void setDone() {
+        isDone = true;
+    }
+}
\ No newline at end of file

From 0e868fe0ecc2e57c5eb2cb4421688bc5a44e6d27 Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Thu, 26 Aug 2021 10:33:50 +0800
Subject: [PATCH 05/25] A-CodingStandard

---
 src/main/java/Greet.java | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/src/main/java/Greet.java b/src/main/java/Greet.java
index c83fac83e..24ef4adbe 100644
--- a/src/main/java/Greet.java
+++ b/src/main/java/Greet.java
@@ -15,15 +15,13 @@ public static void main(String[] args) {
                 for (int i = 0; i < ntasks; i += 1) {
                     System.out.println((i + 1) + ".[" + tasks[i].getStatusIcon() + "] " + tasks[i].getDescription());
                 }
-            }
-            else if (line.contains("done")) {
+            } else if (line.contains("done")) {
                 String[] splitTask = line.split(" ");
                 int index = Integer.parseInt(splitTask[1]) - 1;
                 tasks[index].setDone();
                 System.out.println("Nice! I've marked this task as done:");
                 System.out.println("[" + tasks[index].getStatusIcon() + "] " + tasks[index].getDescription());
-            }
-            else {
+            } else {
                 tasks[ntasks] = new Task(line);
                 ntasks += 1;
                 System.out.println("added: " + line);

From de9dc0ab589cb23f954cd43b0a698f67371d029e Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Wed, 1 Sep 2021 23:44:33 +0800
Subject: [PATCH 06/25] Level-4

---
 src/main/java/Deadline.java | 19 ++++++++
 src/main/java/Duke.java     | 87 ++++++++++++++++++++++++++++++++++---
 src/main/java/Event.java    | 19 ++++++++
 src/main/java/Greet.java    | 33 --------------
 src/main/java/Task.java     |  6 ++-
 src/main/java/Todo.java     | 10 +++++
 6 files changed, 134 insertions(+), 40 deletions(-)
 create mode 100644 src/main/java/Deadline.java
 create mode 100644 src/main/java/Event.java
 delete mode 100644 src/main/java/Greet.java
 create mode 100644 src/main/java/Todo.java

diff --git a/src/main/java/Deadline.java b/src/main/java/Deadline.java
new file mode 100644
index 000000000..8b7afb552
--- /dev/null
+++ b/src/main/java/Deadline.java
@@ -0,0 +1,19 @@
+public class Deadline extends Todo{
+    protected String by;
+
+    public Deadline(String description, String by) {
+        super(description);
+        this.by = by;
+    }
+    public String getBy() {
+        return by;
+    }
+    public void setBy(String by) {
+        this.by = by;
+    }
+
+    public void printTask() {
+        System.out.print("[D][" + getStatusIcon() + "] " + getDescription());
+        System.out.println("(by:" + by + ")");
+    }
+}
diff --git a/src/main/java/Duke.java b/src/main/java/Duke.java
index 5d313334c..8f396b0f7 100644
--- a/src/main/java/Duke.java
+++ b/src/main/java/Duke.java
@@ -1,10 +1,85 @@
+import java.util.Arrays;
+import java.util.Scanner;
+
 public class Duke {
+    public static Task[] tasks = new Task[100];
+    public static int taskCount = 0;
+
+    public static void printGreeting() {
+        System.out.println("Hello! I'm Duke\n" + "What can I do for you?");
+    }
+    public static void printConfused() {
+        System.out.println("Could you say that again?");
+    }
+    public static void printExit() {
+        System.out.println("Bye. Hope to see you again soon!");
+    }
+    public static void printGotIt() {
+        System.out.println("Got it. I've added this task:");
+    }
+    public static void printTaskCount() {
+        System.out.println("Now you have " + taskCount + " tasks in the list.");
+    }
+    public static void printTaskTypeResponse() {
+        printGotIt();
+        tasks[taskCount - 1].printTask();
+        printTaskCount();
+    }
+    public static void printList() {
+        System.out.println("Here are the tasks in your list:");
+        for (int i = 0; i < taskCount; i += 1) {
+            System.out.print((i + 1) + ".");
+            tasks[i].printTask();
+        }
+    }
+    public static void TaskDone(int index) {
+        tasks[index].setDone();
+        System.out.println("Nice! I've marked this task as done:");
+        tasks[index].printTask();
+    }
+    public static void addTodo(String line) {
+        tasks[taskCount] = new Todo(line);
+        taskCount = taskCount + 1;
+        printTaskTypeResponse();
+    }
+    public static void addDeadline(String line) {
+        String description = line.replaceAll("/.+", "");
+        String by = line.replaceAll(".+/by", "");
+        tasks[taskCount] = new Deadline(description, by);
+        taskCount = taskCount + 1;
+        printTaskTypeResponse();
+    }
+    public static void addEvent(String line) {
+        String description = line.replaceAll("/.+", "");
+        String by = line.replaceAll(".+/at", "");
+        tasks[taskCount] = new Event(description, by);
+        taskCount = taskCount + 1;
+        printTaskTypeResponse();
+    }
     public static void main(String[] args) {
-        String logo = " ____        _        \n"
-                + "|  _ \\ _   _| | _____ \n"
-                + "| | | | | | | |/ / _ \\\n"
-                + "| |_| | |_| |   <  __/\n"
-                + "|____/ \\__,_|_|\\_\\___|\n";
-        System.out.println("Hello from\n" + logo);
+        printGreeting();
+        String line;
+        Scanner in = new Scanner(System.in);
+        line = in.nextLine();
+        while (!line.equals("bye")) {
+            if (line.equals("list")) {
+                printList();
+            } else if (line.contains("done")) {
+                String[] splitTask = line.split(" ");
+                int index = Integer.parseInt(splitTask[1]) - 1;
+                tasks[index].setDone();
+                TaskDone(index);
+            } else if (line.contains("todo")) {
+                addTodo(line);
+            } else if (line.contains("deadline")) {
+                addDeadline(line);
+            } else if (line.contains("event")) {
+                addEvent(line);
+            } else {
+                printConfused();
+            }
+            line = in.nextLine();
+        }
+        printExit();
     }
 }
diff --git a/src/main/java/Event.java b/src/main/java/Event.java
new file mode 100644
index 000000000..5c182d07d
--- /dev/null
+++ b/src/main/java/Event.java
@@ -0,0 +1,19 @@
+public class Event extends Todo{
+    protected String at;
+
+    public Event(String description, String at) {
+        super(description);
+        this.at = at;
+    }
+    public String getAt() {
+        return at;
+    }
+    public void setAt(String at) {
+        this.at = at;
+    }
+
+    public void printTask() {
+        System.out.print("[E][" + getStatusIcon() + "] " + getDescription());
+        System.out.println("(at:" + at + ")");
+    }
+}
diff --git a/src/main/java/Greet.java b/src/main/java/Greet.java
deleted file mode 100644
index 24ef4adbe..000000000
--- a/src/main/java/Greet.java
+++ /dev/null
@@ -1,33 +0,0 @@
-import java.util.Arrays;
-import java.util.Scanner;
-
-public class Greet {
-    public static void main(String[] args) {
-        Task[] tasks = new Task[100];
-        int ntasks = 0;
-        System.out.println("Hello! I'm Duke");
-        String line;
-        Scanner in = new Scanner(System.in);
-        System.out.println("What can I do for you?");
-        line = in.nextLine();
-        while (!line.equals("bye")) {
-            if (line.equals("list")) {
-                for (int i = 0; i < ntasks; i += 1) {
-                    System.out.println((i + 1) + ".[" + tasks[i].getStatusIcon() + "] " + tasks[i].getDescription());
-                }
-            } else if (line.contains("done")) {
-                String[] splitTask = line.split(" ");
-                int index = Integer.parseInt(splitTask[1]) - 1;
-                tasks[index].setDone();
-                System.out.println("Nice! I've marked this task as done:");
-                System.out.println("[" + tasks[index].getStatusIcon() + "] " + tasks[index].getDescription());
-            } else {
-                tasks[ntasks] = new Task(line);
-                ntasks += 1;
-                System.out.println("added: " + line);
-            }
-            line = in.nextLine();
-        }
-        System.out.println("Bye. Hope to see you again soon!");
-    }
-}
\ No newline at end of file
diff --git a/src/main/java/Task.java b/src/main/java/Task.java
index 7bca99c9b..fb44f843e 100644
--- a/src/main/java/Task.java
+++ b/src/main/java/Task.java
@@ -4,7 +4,7 @@ public class Task {
 
     public Task(String description) {
         this.description = description;
-        this.isDone = false;
+        isDone = false;
     }
 
     public String getStatusIcon() {
@@ -18,4 +18,8 @@ public String getDescription() {
     public void setDone() {
         isDone = true;
     }
+
+    public void printTask() {
+        System.out.println(description);
+    }
 }
\ No newline at end of file
diff --git a/src/main/java/Todo.java b/src/main/java/Todo.java
new file mode 100644
index 000000000..908ca3a20
--- /dev/null
+++ b/src/main/java/Todo.java
@@ -0,0 +1,10 @@
+public class Todo extends Task{
+
+    public Todo(String description) {
+        super(description);
+    }
+
+    public void printTask() {
+        System.out.println("[T][" + getStatusIcon() + "] " + getDescription());
+    }
+}

From 0061596a35990d9ea5b80f6115c4a1793cbded14 Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Wed, 1 Sep 2021 23:58:08 +0800
Subject: [PATCH 07/25] Revert "Level-4"

This reverts commit de9dc0ab589cb23f954cd43b0a698f67371d029e.
---
 src/main/java/Deadline.java | 19 --------
 src/main/java/Duke.java     | 87 +++----------------------------------
 src/main/java/Event.java    | 19 --------
 src/main/java/Greet.java    | 33 ++++++++++++++
 src/main/java/Task.java     |  6 +--
 src/main/java/Todo.java     | 10 -----
 6 files changed, 40 insertions(+), 134 deletions(-)
 delete mode 100644 src/main/java/Deadline.java
 delete mode 100644 src/main/java/Event.java
 create mode 100644 src/main/java/Greet.java
 delete mode 100644 src/main/java/Todo.java

diff --git a/src/main/java/Deadline.java b/src/main/java/Deadline.java
deleted file mode 100644
index 8b7afb552..000000000
--- a/src/main/java/Deadline.java
+++ /dev/null
@@ -1,19 +0,0 @@
-public class Deadline extends Todo{
-    protected String by;
-
-    public Deadline(String description, String by) {
-        super(description);
-        this.by = by;
-    }
-    public String getBy() {
-        return by;
-    }
-    public void setBy(String by) {
-        this.by = by;
-    }
-
-    public void printTask() {
-        System.out.print("[D][" + getStatusIcon() + "] " + getDescription());
-        System.out.println("(by:" + by + ")");
-    }
-}
diff --git a/src/main/java/Duke.java b/src/main/java/Duke.java
index 8f396b0f7..5d313334c 100644
--- a/src/main/java/Duke.java
+++ b/src/main/java/Duke.java
@@ -1,85 +1,10 @@
-import java.util.Arrays;
-import java.util.Scanner;
-
 public class Duke {
-    public static Task[] tasks = new Task[100];
-    public static int taskCount = 0;
-
-    public static void printGreeting() {
-        System.out.println("Hello! I'm Duke\n" + "What can I do for you?");
-    }
-    public static void printConfused() {
-        System.out.println("Could you say that again?");
-    }
-    public static void printExit() {
-        System.out.println("Bye. Hope to see you again soon!");
-    }
-    public static void printGotIt() {
-        System.out.println("Got it. I've added this task:");
-    }
-    public static void printTaskCount() {
-        System.out.println("Now you have " + taskCount + " tasks in the list.");
-    }
-    public static void printTaskTypeResponse() {
-        printGotIt();
-        tasks[taskCount - 1].printTask();
-        printTaskCount();
-    }
-    public static void printList() {
-        System.out.println("Here are the tasks in your list:");
-        for (int i = 0; i < taskCount; i += 1) {
-            System.out.print((i + 1) + ".");
-            tasks[i].printTask();
-        }
-    }
-    public static void TaskDone(int index) {
-        tasks[index].setDone();
-        System.out.println("Nice! I've marked this task as done:");
-        tasks[index].printTask();
-    }
-    public static void addTodo(String line) {
-        tasks[taskCount] = new Todo(line);
-        taskCount = taskCount + 1;
-        printTaskTypeResponse();
-    }
-    public static void addDeadline(String line) {
-        String description = line.replaceAll("/.+", "");
-        String by = line.replaceAll(".+/by", "");
-        tasks[taskCount] = new Deadline(description, by);
-        taskCount = taskCount + 1;
-        printTaskTypeResponse();
-    }
-    public static void addEvent(String line) {
-        String description = line.replaceAll("/.+", "");
-        String by = line.replaceAll(".+/at", "");
-        tasks[taskCount] = new Event(description, by);
-        taskCount = taskCount + 1;
-        printTaskTypeResponse();
-    }
     public static void main(String[] args) {
-        printGreeting();
-        String line;
-        Scanner in = new Scanner(System.in);
-        line = in.nextLine();
-        while (!line.equals("bye")) {
-            if (line.equals("list")) {
-                printList();
-            } else if (line.contains("done")) {
-                String[] splitTask = line.split(" ");
-                int index = Integer.parseInt(splitTask[1]) - 1;
-                tasks[index].setDone();
-                TaskDone(index);
-            } else if (line.contains("todo")) {
-                addTodo(line);
-            } else if (line.contains("deadline")) {
-                addDeadline(line);
-            } else if (line.contains("event")) {
-                addEvent(line);
-            } else {
-                printConfused();
-            }
-            line = in.nextLine();
-        }
-        printExit();
+        String logo = " ____        _        \n"
+                + "|  _ \\ _   _| | _____ \n"
+                + "| | | | | | | |/ / _ \\\n"
+                + "| |_| | |_| |   <  __/\n"
+                + "|____/ \\__,_|_|\\_\\___|\n";
+        System.out.println("Hello from\n" + logo);
     }
 }
diff --git a/src/main/java/Event.java b/src/main/java/Event.java
deleted file mode 100644
index 5c182d07d..000000000
--- a/src/main/java/Event.java
+++ /dev/null
@@ -1,19 +0,0 @@
-public class Event extends Todo{
-    protected String at;
-
-    public Event(String description, String at) {
-        super(description);
-        this.at = at;
-    }
-    public String getAt() {
-        return at;
-    }
-    public void setAt(String at) {
-        this.at = at;
-    }
-
-    public void printTask() {
-        System.out.print("[E][" + getStatusIcon() + "] " + getDescription());
-        System.out.println("(at:" + at + ")");
-    }
-}
diff --git a/src/main/java/Greet.java b/src/main/java/Greet.java
new file mode 100644
index 000000000..24ef4adbe
--- /dev/null
+++ b/src/main/java/Greet.java
@@ -0,0 +1,33 @@
+import java.util.Arrays;
+import java.util.Scanner;
+
+public class Greet {
+    public static void main(String[] args) {
+        Task[] tasks = new Task[100];
+        int ntasks = 0;
+        System.out.println("Hello! I'm Duke");
+        String line;
+        Scanner in = new Scanner(System.in);
+        System.out.println("What can I do for you?");
+        line = in.nextLine();
+        while (!line.equals("bye")) {
+            if (line.equals("list")) {
+                for (int i = 0; i < ntasks; i += 1) {
+                    System.out.println((i + 1) + ".[" + tasks[i].getStatusIcon() + "] " + tasks[i].getDescription());
+                }
+            } else if (line.contains("done")) {
+                String[] splitTask = line.split(" ");
+                int index = Integer.parseInt(splitTask[1]) - 1;
+                tasks[index].setDone();
+                System.out.println("Nice! I've marked this task as done:");
+                System.out.println("[" + tasks[index].getStatusIcon() + "] " + tasks[index].getDescription());
+            } else {
+                tasks[ntasks] = new Task(line);
+                ntasks += 1;
+                System.out.println("added: " + line);
+            }
+            line = in.nextLine();
+        }
+        System.out.println("Bye. Hope to see you again soon!");
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/Task.java b/src/main/java/Task.java
index fb44f843e..7bca99c9b 100644
--- a/src/main/java/Task.java
+++ b/src/main/java/Task.java
@@ -4,7 +4,7 @@ public class Task {
 
     public Task(String description) {
         this.description = description;
-        isDone = false;
+        this.isDone = false;
     }
 
     public String getStatusIcon() {
@@ -18,8 +18,4 @@ public String getDescription() {
     public void setDone() {
         isDone = true;
     }
-
-    public void printTask() {
-        System.out.println(description);
-    }
 }
\ No newline at end of file
diff --git a/src/main/java/Todo.java b/src/main/java/Todo.java
deleted file mode 100644
index 908ca3a20..000000000
--- a/src/main/java/Todo.java
+++ /dev/null
@@ -1,10 +0,0 @@
-public class Todo extends Task{
-
-    public Todo(String description) {
-        super(description);
-    }
-
-    public void printTask() {
-        System.out.println("[T][" + getStatusIcon() + "] " + getDescription());
-    }
-}

From 860304e6965777b41bca9684b1516f70b0d0c5be Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Thu, 2 Sep 2021 00:17:11 +0800
Subject: [PATCH 08/25] Fixing accidental revert

---
 src/main/java/Deadline.java | 19 ++++++++
 src/main/java/Duke.java     | 87 ++++++++++++++++++++++++++++++++++---
 src/main/java/Event.java    | 19 ++++++++
 src/main/java/Greet.java    | 33 --------------
 src/main/java/Task.java     |  8 +++-
 src/main/java/Todo.java     | 10 +++++
 6 files changed, 135 insertions(+), 41 deletions(-)
 create mode 100644 src/main/java/Deadline.java
 create mode 100644 src/main/java/Event.java
 delete mode 100644 src/main/java/Greet.java
 create mode 100644 src/main/java/Todo.java

diff --git a/src/main/java/Deadline.java b/src/main/java/Deadline.java
new file mode 100644
index 000000000..8b7afb552
--- /dev/null
+++ b/src/main/java/Deadline.java
@@ -0,0 +1,19 @@
+public class Deadline extends Todo{
+    protected String by;
+
+    public Deadline(String description, String by) {
+        super(description);
+        this.by = by;
+    }
+    public String getBy() {
+        return by;
+    }
+    public void setBy(String by) {
+        this.by = by;
+    }
+
+    public void printTask() {
+        System.out.print("[D][" + getStatusIcon() + "] " + getDescription());
+        System.out.println("(by:" + by + ")");
+    }
+}
diff --git a/src/main/java/Duke.java b/src/main/java/Duke.java
index 5d313334c..8f396b0f7 100644
--- a/src/main/java/Duke.java
+++ b/src/main/java/Duke.java
@@ -1,10 +1,85 @@
+import java.util.Arrays;
+import java.util.Scanner;
+
 public class Duke {
+    public static Task[] tasks = new Task[100];
+    public static int taskCount = 0;
+
+    public static void printGreeting() {
+        System.out.println("Hello! I'm Duke\n" + "What can I do for you?");
+    }
+    public static void printConfused() {
+        System.out.println("Could you say that again?");
+    }
+    public static void printExit() {
+        System.out.println("Bye. Hope to see you again soon!");
+    }
+    public static void printGotIt() {
+        System.out.println("Got it. I've added this task:");
+    }
+    public static void printTaskCount() {
+        System.out.println("Now you have " + taskCount + " tasks in the list.");
+    }
+    public static void printTaskTypeResponse() {
+        printGotIt();
+        tasks[taskCount - 1].printTask();
+        printTaskCount();
+    }
+    public static void printList() {
+        System.out.println("Here are the tasks in your list:");
+        for (int i = 0; i < taskCount; i += 1) {
+            System.out.print((i + 1) + ".");
+            tasks[i].printTask();
+        }
+    }
+    public static void TaskDone(int index) {
+        tasks[index].setDone();
+        System.out.println("Nice! I've marked this task as done:");
+        tasks[index].printTask();
+    }
+    public static void addTodo(String line) {
+        tasks[taskCount] = new Todo(line);
+        taskCount = taskCount + 1;
+        printTaskTypeResponse();
+    }
+    public static void addDeadline(String line) {
+        String description = line.replaceAll("/.+", "");
+        String by = line.replaceAll(".+/by", "");
+        tasks[taskCount] = new Deadline(description, by);
+        taskCount = taskCount + 1;
+        printTaskTypeResponse();
+    }
+    public static void addEvent(String line) {
+        String description = line.replaceAll("/.+", "");
+        String by = line.replaceAll(".+/at", "");
+        tasks[taskCount] = new Event(description, by);
+        taskCount = taskCount + 1;
+        printTaskTypeResponse();
+    }
     public static void main(String[] args) {
-        String logo = " ____        _        \n"
-                + "|  _ \\ _   _| | _____ \n"
-                + "| | | | | | | |/ / _ \\\n"
-                + "| |_| | |_| |   <  __/\n"
-                + "|____/ \\__,_|_|\\_\\___|\n";
-        System.out.println("Hello from\n" + logo);
+        printGreeting();
+        String line;
+        Scanner in = new Scanner(System.in);
+        line = in.nextLine();
+        while (!line.equals("bye")) {
+            if (line.equals("list")) {
+                printList();
+            } else if (line.contains("done")) {
+                String[] splitTask = line.split(" ");
+                int index = Integer.parseInt(splitTask[1]) - 1;
+                tasks[index].setDone();
+                TaskDone(index);
+            } else if (line.contains("todo")) {
+                addTodo(line);
+            } else if (line.contains("deadline")) {
+                addDeadline(line);
+            } else if (line.contains("event")) {
+                addEvent(line);
+            } else {
+                printConfused();
+            }
+            line = in.nextLine();
+        }
+        printExit();
     }
 }
diff --git a/src/main/java/Event.java b/src/main/java/Event.java
new file mode 100644
index 000000000..5c182d07d
--- /dev/null
+++ b/src/main/java/Event.java
@@ -0,0 +1,19 @@
+public class Event extends Todo{
+    protected String at;
+
+    public Event(String description, String at) {
+        super(description);
+        this.at = at;
+    }
+    public String getAt() {
+        return at;
+    }
+    public void setAt(String at) {
+        this.at = at;
+    }
+
+    public void printTask() {
+        System.out.print("[E][" + getStatusIcon() + "] " + getDescription());
+        System.out.println("(at:" + at + ")");
+    }
+}
diff --git a/src/main/java/Greet.java b/src/main/java/Greet.java
deleted file mode 100644
index 24ef4adbe..000000000
--- a/src/main/java/Greet.java
+++ /dev/null
@@ -1,33 +0,0 @@
-import java.util.Arrays;
-import java.util.Scanner;
-
-public class Greet {
-    public static void main(String[] args) {
-        Task[] tasks = new Task[100];
-        int ntasks = 0;
-        System.out.println("Hello! I'm Duke");
-        String line;
-        Scanner in = new Scanner(System.in);
-        System.out.println("What can I do for you?");
-        line = in.nextLine();
-        while (!line.equals("bye")) {
-            if (line.equals("list")) {
-                for (int i = 0; i < ntasks; i += 1) {
-                    System.out.println((i + 1) + ".[" + tasks[i].getStatusIcon() + "] " + tasks[i].getDescription());
-                }
-            } else if (line.contains("done")) {
-                String[] splitTask = line.split(" ");
-                int index = Integer.parseInt(splitTask[1]) - 1;
-                tasks[index].setDone();
-                System.out.println("Nice! I've marked this task as done:");
-                System.out.println("[" + tasks[index].getStatusIcon() + "] " + tasks[index].getDescription());
-            } else {
-                tasks[ntasks] = new Task(line);
-                ntasks += 1;
-                System.out.println("added: " + line);
-            }
-            line = in.nextLine();
-        }
-        System.out.println("Bye. Hope to see you again soon!");
-    }
-}
\ No newline at end of file
diff --git a/src/main/java/Task.java b/src/main/java/Task.java
index 7bca99c9b..900881e8a 100644
--- a/src/main/java/Task.java
+++ b/src/main/java/Task.java
@@ -4,7 +4,7 @@ public class Task {
 
     public Task(String description) {
         this.description = description;
-        this.isDone = false;
+        isDone = false;
     }
 
     public String getStatusIcon() {
@@ -18,4 +18,8 @@ public String getDescription() {
     public void setDone() {
         isDone = true;
     }
-}
\ No newline at end of file
+
+    public void printTask() {
+        System.out.println(description);
+    }
+}
diff --git a/src/main/java/Todo.java b/src/main/java/Todo.java
new file mode 100644
index 000000000..908ca3a20
--- /dev/null
+++ b/src/main/java/Todo.java
@@ -0,0 +1,10 @@
+public class Todo extends Task{
+
+    public Todo(String description) {
+        super(description);
+    }
+
+    public void printTask() {
+        System.out.println("[T][" + getStatusIcon() + "] " + getDescription());
+    }
+}

From 466cbeea100643e8d21e8e7f8def93afa8c08c17 Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Thu, 2 Sep 2021 00:49:56 +0800
Subject: [PATCH 09/25] Incomplete A-TextUiTesting

---
 text-ui-test/EXPECTED.TXT | 33 +++++++++++++++++++++++++++------
 text-ui-test/input.txt    |  8 ++++++++
 text-ui-test/runtest.bat  |  4 ++--
 3 files changed, 37 insertions(+), 8 deletions(-)

diff --git a/text-ui-test/EXPECTED.TXT b/text-ui-test/EXPECTED.TXT
index 657e74f6e..e17c0c057 100644
--- a/text-ui-test/EXPECTED.TXT
+++ b/text-ui-test/EXPECTED.TXT
@@ -1,7 +1,28 @@
-Hello from
- ____        _        
-|  _ \ _   _| | _____ 
-| | | | | | | |/ / _ \
-| |_| | |_| |   <  __/
-|____/ \__,_|_|\_\___|
+Hello! I'm Duke
+What can I do for you?
 
+Could you say that again?
+
+Got it. I've added this task:
+[T][ ] todo eat cake
+Now you have 1 tasks in the list.
+
+Got it. I've added this task:
+[D][ ] deadline eat chocolate cake (by: Friday 2pm)
+Now you have 2 tasks in the list.
+
+Got it. I've added this task:
+[E][ ] event attend cake buffet (at: Saturday 5pm)
+Now you have 3 tasks in the list.
+
+Nice! I've marked this task as done:
+[T][X] todo eat cake
+
+Here are the tasks in your list:
+1.[T][X] todo eat cake
+2.[D][ ] deadline eat chocolate cake (by: Friday 2pm)
+3.[E][ ] event attend cake buffet (at: Saturday 5pm)
+
+Could you say that again?
+
+Bye. Hope to see you again soon!
diff --git a/text-ui-test/input.txt b/text-ui-test/input.txt
index e69de29bb..bc9f12c2f 100644
--- a/text-ui-test/input.txt
+++ b/text-ui-test/input.txt
@@ -0,0 +1,8 @@
+eat cake
+todo eat cake
+deadline eat chocolate cake /by Friday 2pm
+event attend cake buffet /at Saturday 5pm
+done 1
+list
+cake
+bye
\ No newline at end of file
diff --git a/text-ui-test/runtest.bat b/text-ui-test/runtest.bat
index 087374464..f0f1ef7b2 100644
--- a/text-ui-test/runtest.bat
+++ b/text-ui-test/runtest.bat
@@ -7,7 +7,7 @@ REM delete output from previous run
 if exist ACTUAL.TXT del ACTUAL.TXT
 
 REM compile the code into the bin folder
-javac  -cp ..\src\main\java -Xlint:none -d ..\bin ..\src\main\java\*.java
+javac  -cp D:\NUS\Sem 3\CS2113\ip-master\src\main\java -Xlint:none -d D:\NUS\Sem 3\CS2113\jdk11.0.12_7\bin D:\NUS\Sem 3\CS2113\ip-master\src\main\java\Duke.java
 IF ERRORLEVEL 1 (
     echo ********** BUILD FAILURE **********
     exit /b 1
@@ -15,7 +15,7 @@ IF ERRORLEVEL 1 (
 REM no error here, errorlevel == 0
 
 REM run the program, feed commands from input.txt file and redirect the output to the ACTUAL.TXT
-java -classpath ..\bin Duke < input.txt > ACTUAL.TXT
+java -classpath D:\NUS\Sem 3\CS2113\jdk11.0.12_7\bin Duke < input.txt > ACTUAL.TXT
 
 REM compare the output to the expected output
 FC ACTUAL.TXT EXPECTED.TXT

From 781043a4ea55f88f6a5f4c0f96194824d92131ff Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Thu, 2 Sep 2021 01:00:20 +0800
Subject: [PATCH 10/25] A-CodeQuality

---
 src/main/java/Duke.java | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/main/java/Duke.java b/src/main/java/Duke.java
index 8f396b0f7..a732853ec 100644
--- a/src/main/java/Duke.java
+++ b/src/main/java/Duke.java
@@ -21,6 +21,7 @@ public static void printTaskCount() {
         System.out.println("Now you have " + taskCount + " tasks in the list.");
     }
     public static void printTaskTypeResponse() {
+        //printing different responses depending if its Todo/Deadline/Event
         printGotIt();
         tasks[taskCount - 1].printTask();
         printTaskCount();
@@ -43,6 +44,7 @@ public static void addTodo(String line) {
         printTaskTypeResponse();
     }
     public static void addDeadline(String line) {
+        //extracting the description and date
         String description = line.replaceAll("/.+", "");
         String by = line.replaceAll(".+/by", "");
         tasks[taskCount] = new Deadline(description, by);
@@ -50,6 +52,7 @@ public static void addDeadline(String line) {
         printTaskTypeResponse();
     }
     public static void addEvent(String line) {
+        //extracting the description and date
         String description = line.replaceAll("/.+", "");
         String by = line.replaceAll(".+/at", "");
         tasks[taskCount] = new Event(description, by);
@@ -61,10 +64,12 @@ public static void main(String[] args) {
         String line;
         Scanner in = new Scanner(System.in);
         line = in.nextLine();
+        //continue to run program unless types "bye" to exit program
         while (!line.equals("bye")) {
             if (line.equals("list")) {
                 printList();
             } else if (line.contains("done")) {
+                //find which task user is done with
                 String[] splitTask = line.split(" ");
                 int index = Integer.parseInt(splitTask[1]) - 1;
                 tasks[index].setDone();
@@ -76,6 +81,7 @@ public static void main(String[] args) {
             } else if (line.contains("event")) {
                 addEvent(line);
             } else {
+                //error with input
                 printConfused();
             }
             line = in.nextLine();

From 50e7e6b721f0f8d6a1579fff267dc8c997e65a6d Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Thu, 2 Sep 2021 01:00:53 +0800
Subject: [PATCH 11/25] Shifting comment line

---
 src/main/java/Task.java | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/main/java/Task.java b/src/main/java/Task.java
index 900881e8a..b384a5060 100644
--- a/src/main/java/Task.java
+++ b/src/main/java/Task.java
@@ -8,7 +8,8 @@ public Task(String description) {
     }
 
     public String getStatusIcon() {
-        return (isDone ? "X" : " "); // mark done task with X
+        // mark done task with X
+        return (isDone ? "X" : " ");
     }
 
     public String getDescription() {

From a6b0cb4690b1781b6d871c67b3ad91537aa4d43d Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Thu, 2 Sep 2021 02:13:58 +0800
Subject: [PATCH 12/25] Altering runtest.bat

---
 text-ui-test/runtest.bat | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/text-ui-test/runtest.bat b/text-ui-test/runtest.bat
index f0f1ef7b2..4883b1056 100644
--- a/text-ui-test/runtest.bat
+++ b/text-ui-test/runtest.bat
@@ -7,7 +7,7 @@ REM delete output from previous run
 if exist ACTUAL.TXT del ACTUAL.TXT
 
 REM compile the code into the bin folder
-javac  -cp D:\NUS\Sem 3\CS2113\ip-master\src\main\java -Xlint:none -d D:\NUS\Sem 3\CS2113\jdk11.0.12_7\bin D:\NUS\Sem 3\CS2113\ip-master\src\main\java\Duke.java
+javac  -cp D:\NUS\Sem3\CS2113\ip\src\main\java -Xlint:none -d D:\NUS\Sem3\CS2113\jdk11.0.12_7\bin D:\NUS\Sem 3\CS2113\ip\src\main\java\Duke.java
 IF ERRORLEVEL 1 (
     echo ********** BUILD FAILURE **********
     exit /b 1
@@ -15,7 +15,7 @@ IF ERRORLEVEL 1 (
 REM no error here, errorlevel == 0
 
 REM run the program, feed commands from input.txt file and redirect the output to the ACTUAL.TXT
-java -classpath D:\NUS\Sem 3\CS2113\jdk11.0.12_7\bin Duke < input.txt > ACTUAL.TXT
+java -classpath D:\NUS\Sem3\CS2113\jdk11.0.12_7\bin Duke < input.txt > ACTUAL.TXT
 
 REM compare the output to the expected output
 FC ACTUAL.TXT EXPECTED.TXT

From 81aba6144bbde54f674aa1eeb322bca16cccdc74 Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Thu, 2 Sep 2021 22:15:55 +0800
Subject: [PATCH 13/25] A-TextUiTesting update

---
 text-ui-test/EXPECTED.TXT | 8 --------
 text-ui-test/runtest.bat  | 6 +++---
 2 files changed, 3 insertions(+), 11 deletions(-)

diff --git a/text-ui-test/EXPECTED.TXT b/text-ui-test/EXPECTED.TXT
index e17c0c057..f1aa31c20 100644
--- a/text-ui-test/EXPECTED.TXT
+++ b/text-ui-test/EXPECTED.TXT
@@ -1,28 +1,20 @@
 Hello! I'm Duke
 What can I do for you?
-
 Could you say that again?
-
 Got it. I've added this task:
 [T][ ] todo eat cake
 Now you have 1 tasks in the list.
-
 Got it. I've added this task:
 [D][ ] deadline eat chocolate cake (by: Friday 2pm)
 Now you have 2 tasks in the list.
-
 Got it. I've added this task:
 [E][ ] event attend cake buffet (at: Saturday 5pm)
 Now you have 3 tasks in the list.
-
 Nice! I've marked this task as done:
 [T][X] todo eat cake
-
 Here are the tasks in your list:
 1.[T][X] todo eat cake
 2.[D][ ] deadline eat chocolate cake (by: Friday 2pm)
 3.[E][ ] event attend cake buffet (at: Saturday 5pm)
-
 Could you say that again?
-
 Bye. Hope to see you again soon!
diff --git a/text-ui-test/runtest.bat b/text-ui-test/runtest.bat
index 4883b1056..1a491cd91 100644
--- a/text-ui-test/runtest.bat
+++ b/text-ui-test/runtest.bat
@@ -4,10 +4,10 @@ REM create bin directory if it doesn't exist
 if not exist ..\bin mkdir ..\bin
 
 REM delete output from previous run
-if exist ACTUAL.TXT del ACTUAL.TXT
+del ACTUAL.TXT
 
 REM compile the code into the bin folder
-javac  -cp D:\NUS\Sem3\CS2113\ip\src\main\java -Xlint:none -d D:\NUS\Sem3\CS2113\jdk11.0.12_7\bin D:\NUS\Sem 3\CS2113\ip\src\main\java\Duke.java
+javac  -cp ..\src\main\java -Xlint:none -d ..\bin ..\src\main\java\*.java
 IF ERRORLEVEL 1 (
     echo ********** BUILD FAILURE **********
     exit /b 1
@@ -15,7 +15,7 @@ IF ERRORLEVEL 1 (
 REM no error here, errorlevel == 0
 
 REM run the program, feed commands from input.txt file and redirect the output to the ACTUAL.TXT
-java -classpath D:\NUS\Sem3\CS2113\jdk11.0.12_7\bin Duke < input.txt > ACTUAL.TXT
+java -classpath ..\bin Duke < input.txt > ACTUAL.TXT
 
 REM compare the output to the expected output
 FC ACTUAL.TXT EXPECTED.TXT

From dcd1d9122cbbce8050e0655f7f5aa60556d6b45e Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Thu, 9 Sep 2021 00:10:06 +0800
Subject: [PATCH 14/25] Level-5

---
 src/main/java/DeadlineException.java |   2 +
 src/main/java/Duke.java              | 132 +++++++++++++++++++--------
 src/main/java/EventException.java    |   2 +
 src/main/java/TodoException.java     |   2 +
 4 files changed, 98 insertions(+), 40 deletions(-)
 create mode 100644 src/main/java/DeadlineException.java
 create mode 100644 src/main/java/EventException.java
 create mode 100644 src/main/java/TodoException.java

diff --git a/src/main/java/DeadlineException.java b/src/main/java/DeadlineException.java
new file mode 100644
index 000000000..133d1183a
--- /dev/null
+++ b/src/main/java/DeadlineException.java
@@ -0,0 +1,2 @@
+public class DeadlineException extends Exception{
+}
diff --git a/src/main/java/Duke.java b/src/main/java/Duke.java
index a732853ec..3928da0cd 100644
--- a/src/main/java/Duke.java
+++ b/src/main/java/Duke.java
@@ -8,24 +8,42 @@ public class Duke {
     public static void printGreeting() {
         System.out.println("Hello! I'm Duke\n" + "What can I do for you?");
     }
+
     public static void printConfused() {
         System.out.println("Could you say that again?");
     }
+
     public static void printExit() {
         System.out.println("Bye. Hope to see you again soon!");
     }
+
     public static void printGotIt() {
         System.out.println("Got it. I've added this task:");
     }
+
     public static void printTaskCount() {
         System.out.println("Now you have " + taskCount + " tasks in the list.");
     }
+
+    public static void printTodoException() {
+        System.out.println("The description of todo cannot be empty.");
+    }
+
+    public static void printDeadlineException() {
+        System.out.println("The description of deadline cannot be empty.");
+    }
+
+    public static void printEventException() {
+        System.out.println("The description of event cannot be empty.");
+    }
+
     public static void printTaskTypeResponse() {
         //printing different responses depending if its Todo/Deadline/Event
         printGotIt();
         tasks[taskCount - 1].printTask();
         printTaskCount();
     }
+
     public static void printList() {
         System.out.println("Here are the tasks in your list:");
         for (int i = 0; i < taskCount; i += 1) {
@@ -33,59 +51,93 @@ public static void printList() {
             tasks[i].printTask();
         }
     }
+
     public static void TaskDone(int index) {
         tasks[index].setDone();
         System.out.println("Nice! I've marked this task as done:");
         tasks[index].printTask();
     }
-    public static void addTodo(String line) {
-        tasks[taskCount] = new Todo(line);
-        taskCount = taskCount + 1;
-        printTaskTypeResponse();
-    }
-    public static void addDeadline(String line) {
-        //extracting the description and date
-        String description = line.replaceAll("/.+", "");
-        String by = line.replaceAll(".+/by", "");
-        tasks[taskCount] = new Deadline(description, by);
-        taskCount = taskCount + 1;
-        printTaskTypeResponse();
-    }
-    public static void addEvent(String line) {
-        //extracting the description and date
-        String description = line.replaceAll("/.+", "");
-        String by = line.replaceAll(".+/at", "");
-        tasks[taskCount] = new Event(description, by);
-        taskCount = taskCount + 1;
-        printTaskTypeResponse();
+
+    public static void addTodo(String line) throws TodoException {
+        if (line.equals("") || line.equals("todo")) {
+            throw new TodoException();
+        } else {
+            tasks[taskCount] = new Todo(line);
+            taskCount = taskCount + 1;
+            printTaskTypeResponse();
+        }
+    }
+
+    public static void addDeadline(String line) throws DeadlineException {
+        if (!line.matches("(.*)/by(.*)")) {
+            throw new DeadlineException();
+        } else {
+            //extracting the description and date
+            String description = line.replaceAll("/.+", "");
+            String by = line.replaceAll(".+/by", "");
+            tasks[taskCount] = new Deadline(description, by);
+            taskCount = taskCount + 1;
+            printTaskTypeResponse();
+        }
     }
+
+    public static void addEvent(String line) throws EventException {
+        if (!line.matches("(.*)/at(.*)")) {
+            throw new EventException();
+        } else {
+            //extracting the description and date
+            String description = line.replaceAll("/.+", "");
+            String by = line.replaceAll(".+/at", "");
+            tasks[taskCount] = new Event(description, by);
+            taskCount = taskCount + 1;
+            printTaskTypeResponse();
+        }
+    }
+
+    public static void readInput(String line) {
+        String[] splitLine = line.split(" ", 2);
+        String command = splitLine[0];
+        line = line.replaceAll("^" + command + " ", "");
+        if (command.equals("list")) {
+            printList();
+        } else if (command.equals("done")) {
+            //find which task user is done with
+            int index = Integer.parseInt(line) - 1;
+            tasks[index].setDone();
+            TaskDone(index);
+        } else if (command.equals("todo")) {
+            try {
+                addTodo(line);
+            } catch (TodoException e) {
+                printTodoException();
+            }
+        } else if (command.equals("deadline")) {
+            try {
+                addDeadline(line);
+            } catch (DeadlineException e) {
+                printDeadlineException();
+            }
+        } else if (command.equals("event")) {
+            try {
+                addEvent(line);
+            } catch (EventException e) {
+                printEventException();
+            }
+        } else {
+            //error with input
+            printConfused();
+        }
+    }
+
     public static void main(String[] args) {
         printGreeting();
         String line;
         Scanner in = new Scanner(System.in);
         line = in.nextLine();
         //continue to run program unless types "bye" to exit program
-        while (!line.equals("bye")) {
-            if (line.equals("list")) {
-                printList();
-            } else if (line.contains("done")) {
-                //find which task user is done with
-                String[] splitTask = line.split(" ");
-                int index = Integer.parseInt(splitTask[1]) - 1;
-                tasks[index].setDone();
-                TaskDone(index);
-            } else if (line.contains("todo")) {
-                addTodo(line);
-            } else if (line.contains("deadline")) {
-                addDeadline(line);
-            } else if (line.contains("event")) {
-                addEvent(line);
-            } else {
-                //error with input
-                printConfused();
-            }
+        while(!line.equals("bye")) {
+            readInput(line);
             line = in.nextLine();
         }
-        printExit();
     }
 }
diff --git a/src/main/java/EventException.java b/src/main/java/EventException.java
new file mode 100644
index 000000000..14ba8baaa
--- /dev/null
+++ b/src/main/java/EventException.java
@@ -0,0 +1,2 @@
+public class EventException extends Exception{
+}
diff --git a/src/main/java/TodoException.java b/src/main/java/TodoException.java
new file mode 100644
index 000000000..737bb4f60
--- /dev/null
+++ b/src/main/java/TodoException.java
@@ -0,0 +1,2 @@
+public class TodoException extends Exception{
+}

From 63405a4f96096f0ba9c0bd1ce369ed7589f31cce Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Thu, 9 Sep 2021 00:50:57 +0800
Subject: [PATCH 15/25] A-Packages

---
 src/main/java/{ => duke}/Deadline.java          | 2 ++
 src/main/java/{ => duke}/DeadlineException.java | 2 ++
 src/main/java/{ => duke}/Duke.java              | 5 +++--
 src/main/java/{ => duke}/Event.java             | 2 ++
 src/main/java/{ => duke}/EventException.java    | 2 ++
 src/main/java/{ => duke}/Task.java              | 2 ++
 src/main/java/{ => duke}/Todo.java              | 2 ++
 src/main/java/{ => duke}/TodoException.java     | 2 ++
 8 files changed, 17 insertions(+), 2 deletions(-)
 rename src/main/java/{ => duke}/Deadline.java (96%)
 rename src/main/java/{ => duke}/DeadlineException.java (77%)
 rename src/main/java/{ => duke}/Duke.java (97%)
 rename src/main/java/{ => duke}/Event.java (96%)
 rename src/main/java/{ => duke}/EventException.java (76%)
 rename src/main/java/{ => duke}/Task.java (97%)
 rename src/main/java/{ => duke}/Todo.java (93%)
 rename src/main/java/{ => duke}/TodoException.java (76%)

diff --git a/src/main/java/Deadline.java b/src/main/java/duke/Deadline.java
similarity index 96%
rename from src/main/java/Deadline.java
rename to src/main/java/duke/Deadline.java
index 8b7afb552..f8cae570c 100644
--- a/src/main/java/Deadline.java
+++ b/src/main/java/duke/Deadline.java
@@ -1,3 +1,5 @@
+package duke;
+
 public class Deadline extends Todo{
     protected String by;
 
diff --git a/src/main/java/DeadlineException.java b/src/main/java/duke/DeadlineException.java
similarity index 77%
rename from src/main/java/DeadlineException.java
rename to src/main/java/duke/DeadlineException.java
index 133d1183a..96eb5dda9 100644
--- a/src/main/java/DeadlineException.java
+++ b/src/main/java/duke/DeadlineException.java
@@ -1,2 +1,4 @@
+package duke;
+
 public class DeadlineException extends Exception{
 }
diff --git a/src/main/java/Duke.java b/src/main/java/duke/Duke.java
similarity index 97%
rename from src/main/java/Duke.java
rename to src/main/java/duke/Duke.java
index 3928da0cd..1a04898d6 100644
--- a/src/main/java/Duke.java
+++ b/src/main/java/duke/Duke.java
@@ -1,4 +1,5 @@
-import java.util.Arrays;
+package duke;
+
 import java.util.Scanner;
 
 public class Duke {
@@ -38,7 +39,7 @@ public static void printEventException() {
     }
 
     public static void printTaskTypeResponse() {
-        //printing different responses depending if its Todo/Deadline/Event
+        //printing different responses depending if its duke.Todo/duke.Deadline/duke.Event
         printGotIt();
         tasks[taskCount - 1].printTask();
         printTaskCount();
diff --git a/src/main/java/Event.java b/src/main/java/duke/Event.java
similarity index 96%
rename from src/main/java/Event.java
rename to src/main/java/duke/Event.java
index 5c182d07d..df8c6a880 100644
--- a/src/main/java/Event.java
+++ b/src/main/java/duke/Event.java
@@ -1,3 +1,5 @@
+package duke;
+
 public class Event extends Todo{
     protected String at;
 
diff --git a/src/main/java/EventException.java b/src/main/java/duke/EventException.java
similarity index 76%
rename from src/main/java/EventException.java
rename to src/main/java/duke/EventException.java
index 14ba8baaa..b4366936d 100644
--- a/src/main/java/EventException.java
+++ b/src/main/java/duke/EventException.java
@@ -1,2 +1,4 @@
+package duke;
+
 public class EventException extends Exception{
 }
diff --git a/src/main/java/Task.java b/src/main/java/duke/Task.java
similarity index 97%
rename from src/main/java/Task.java
rename to src/main/java/duke/Task.java
index b384a5060..8c6172d16 100644
--- a/src/main/java/Task.java
+++ b/src/main/java/duke/Task.java
@@ -1,3 +1,5 @@
+package duke;
+
 public class Task {
     protected String description;
     protected boolean isDone;
diff --git a/src/main/java/Todo.java b/src/main/java/duke/Todo.java
similarity index 93%
rename from src/main/java/Todo.java
rename to src/main/java/duke/Todo.java
index 908ca3a20..80195adbc 100644
--- a/src/main/java/Todo.java
+++ b/src/main/java/duke/Todo.java
@@ -1,3 +1,5 @@
+package duke;
+
 public class Todo extends Task{
 
     public Todo(String description) {
diff --git a/src/main/java/TodoException.java b/src/main/java/duke/TodoException.java
similarity index 76%
rename from src/main/java/TodoException.java
rename to src/main/java/duke/TodoException.java
index 737bb4f60..66545fe54 100644
--- a/src/main/java/TodoException.java
+++ b/src/main/java/duke/TodoException.java
@@ -1,2 +1,4 @@
+package duke;
+
 public class TodoException extends Exception{
 }

From 9096123dd780d6ec95247807f715ffa840f45e65 Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Thu, 9 Sep 2021 09:58:49 +0800
Subject: [PATCH 16/25] Updated runtest and exceptions.

---
 src/main/java/duke/DoneException.java      |  4 ++++
 src/main/java/duke/Duke.java               | 28 +++++++++++++++-------
 src/main/java/duke/TaskCountException.java |  4 ++++
 text-ui-test/EXPECTED.TXT                  | 16 ++++++-------
 text-ui-test/input.txt                     |  1 +
 text-ui-test/runtest.bat                   |  4 ++--
 6 files changed, 39 insertions(+), 18 deletions(-)
 create mode 100644 src/main/java/duke/DoneException.java
 create mode 100644 src/main/java/duke/TaskCountException.java

diff --git a/src/main/java/duke/DoneException.java b/src/main/java/duke/DoneException.java
new file mode 100644
index 000000000..674670a8a
--- /dev/null
+++ b/src/main/java/duke/DoneException.java
@@ -0,0 +1,4 @@
+package duke;
+
+public class DoneException extends Exception{
+}
diff --git a/src/main/java/duke/Duke.java b/src/main/java/duke/Duke.java
index 1a04898d6..1e1c36654 100644
--- a/src/main/java/duke/Duke.java
+++ b/src/main/java/duke/Duke.java
@@ -38,6 +38,10 @@ public static void printEventException() {
         System.out.println("The description of event cannot be empty.");
     }
 
+    public static void printDoneException() {
+        System.out.println("The description of done cannot be empty.");
+    }
+
     public static void printTaskTypeResponse() {
         //printing different responses depending if its duke.Todo/duke.Deadline/duke.Event
         printGotIt();
@@ -53,10 +57,15 @@ public static void printList() {
         }
     }
 
-    public static void TaskDone(int index) {
-        tasks[index].setDone();
-        System.out.println("Nice! I've marked this task as done:");
-        tasks[index].printTask();
+    public static void taskDone(String line) throws DoneException {
+        if (line.equals("") || line.equals("done")) {
+            throw new DoneException();
+        } else {
+            int index = Integer.parseInt(line) - 1;
+            tasks[index].setDone();
+            System.out.println("Nice! I've marked this task as done:");
+            tasks[index].printTask();
+        }
     }
 
     public static void addTodo(String line) throws TodoException {
@@ -102,10 +111,12 @@ public static void readInput(String line) {
         if (command.equals("list")) {
             printList();
         } else if (command.equals("done")) {
-            //find which task user is done with
-            int index = Integer.parseInt(line) - 1;
-            tasks[index].setDone();
-            TaskDone(index);
+            try {
+                //find which task user is done with
+                taskDone(line);
+            } catch (DoneException e) {
+                printDoneException();
+            }
         } else if (command.equals("todo")) {
             try {
                 addTodo(line);
@@ -140,5 +151,6 @@ public static void main(String[] args) {
             readInput(line);
             line = in.nextLine();
         }
+        printExit();
     }
 }
diff --git a/src/main/java/duke/TaskCountException.java b/src/main/java/duke/TaskCountException.java
new file mode 100644
index 000000000..b42b9e248
--- /dev/null
+++ b/src/main/java/duke/TaskCountException.java
@@ -0,0 +1,4 @@
+package duke;
+
+public class TaskCountException extends Exception{
+}
diff --git a/text-ui-test/EXPECTED.TXT b/text-ui-test/EXPECTED.TXT
index f1aa31c20..0cdc00662 100644
--- a/text-ui-test/EXPECTED.TXT
+++ b/text-ui-test/EXPECTED.TXT
@@ -2,19 +2,19 @@ Hello! I'm Duke
 What can I do for you?
 Could you say that again?
 Got it. I've added this task:
-[T][ ] todo eat cake
+[T][ ] eat cake
 Now you have 1 tasks in the list.
 Got it. I've added this task:
-[D][ ] deadline eat chocolate cake (by: Friday 2pm)
+[D][ ] eat chocolate cake (by: Friday 2pm)
 Now you have 2 tasks in the list.
 Got it. I've added this task:
-[E][ ] event attend cake buffet (at: Saturday 5pm)
+[E][ ] attend cake buffet (at: Saturday 5pm)
 Now you have 3 tasks in the list.
 Nice! I've marked this task as done:
-[T][X] todo eat cake
+[T][X] eat cake
+The description of todo cannot be empty.
 Here are the tasks in your list:
-1.[T][X] todo eat cake
-2.[D][ ] deadline eat chocolate cake (by: Friday 2pm)
-3.[E][ ] event attend cake buffet (at: Saturday 5pm)
+1.[T][X] eat cake
+2.[D][ ] eat chocolate cake (by: Friday 2pm)
+3.[E][ ] attend cake buffet (at: Saturday 5pm)
 Could you say that again?
-Bye. Hope to see you again soon!
diff --git a/text-ui-test/input.txt b/text-ui-test/input.txt
index bc9f12c2f..bec17eb26 100644
--- a/text-ui-test/input.txt
+++ b/text-ui-test/input.txt
@@ -3,6 +3,7 @@ todo eat cake
 deadline eat chocolate cake /by Friday 2pm
 event attend cake buffet /at Saturday 5pm
 done 1
+todo
 list
 cake
 bye
\ No newline at end of file
diff --git a/text-ui-test/runtest.bat b/text-ui-test/runtest.bat
index 1a491cd91..9dec60887 100644
--- a/text-ui-test/runtest.bat
+++ b/text-ui-test/runtest.bat
@@ -7,7 +7,7 @@ REM delete output from previous run
 del ACTUAL.TXT
 
 REM compile the code into the bin folder
-javac  -cp ..\src\main\java -Xlint:none -d ..\bin ..\src\main\java\*.java
+javac  -cp ..\src\main\java -Xlint:none -d ..\bin ..\src\main\java\duke\*.java
 IF ERRORLEVEL 1 (
     echo ********** BUILD FAILURE **********
     exit /b 1
@@ -15,7 +15,7 @@ IF ERRORLEVEL 1 (
 REM no error here, errorlevel == 0
 
 REM run the program, feed commands from input.txt file and redirect the output to the ACTUAL.TXT
-java -classpath ..\bin Duke < input.txt > ACTUAL.TXT
+java -classpath ..\bin duke.Duke < input.txt > ACTUAL.TXT
 
 REM compare the output to the expected output
 FC ACTUAL.TXT EXPECTED.TXT

From f6335dc152bda89f5ee3910f8541ac77a709198f Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Wed, 15 Sep 2021 00:00:20 +0800
Subject: [PATCH 17/25] Reformat files, add branch-Level-6, Level-6 and
 A-Collections

---
 src/main/java/duke/DeadlineException.java  |  2 +-
 src/main/java/duke/DeleteException.java    |  4 ++
 src/main/java/duke/DoneException.java      |  2 +-
 src/main/java/duke/Duke.java               | 57 ++++++++++++++++------
 src/main/java/duke/EventException.java     |  2 +-
 src/main/java/duke/TaskCountException.java |  2 +-
 src/main/java/duke/TodoException.java      |  2 +-
 7 files changed, 51 insertions(+), 20 deletions(-)
 create mode 100644 src/main/java/duke/DeleteException.java

diff --git a/src/main/java/duke/DeadlineException.java b/src/main/java/duke/DeadlineException.java
index 96eb5dda9..b6c92aff2 100644
--- a/src/main/java/duke/DeadlineException.java
+++ b/src/main/java/duke/DeadlineException.java
@@ -1,4 +1,4 @@
 package duke;
 
-public class DeadlineException extends Exception{
+public class DeadlineException extends Exception {
 }
diff --git a/src/main/java/duke/DeleteException.java b/src/main/java/duke/DeleteException.java
new file mode 100644
index 000000000..baea749ed
--- /dev/null
+++ b/src/main/java/duke/DeleteException.java
@@ -0,0 +1,4 @@
+package duke;
+
+public class DeleteException extends Exception {
+}
diff --git a/src/main/java/duke/DoneException.java b/src/main/java/duke/DoneException.java
index 674670a8a..e0512ebec 100644
--- a/src/main/java/duke/DoneException.java
+++ b/src/main/java/duke/DoneException.java
@@ -1,4 +1,4 @@
 package duke;
 
-public class DoneException extends Exception{
+public class DoneException extends Exception {
 }
diff --git a/src/main/java/duke/Duke.java b/src/main/java/duke/Duke.java
index 1e1c36654..db4c5746a 100644
--- a/src/main/java/duke/Duke.java
+++ b/src/main/java/duke/Duke.java
@@ -1,10 +1,10 @@
 package duke;
 
+import java.util.ArrayList;
 import java.util.Scanner;
 
 public class Duke {
-    public static Task[] tasks = new Task[100];
-    public static int taskCount = 0;
+    public static ArrayList<Task> tasks = new ArrayList<>();
 
     public static void printGreeting() {
         System.out.println("Hello! I'm Duke\n" + "What can I do for you?");
@@ -22,8 +22,12 @@ public static void printGotIt() {
         System.out.println("Got it. I've added this task:");
     }
 
+    public static void printRemoveIt() {
+        System.out.println("Noted. I've removed this task:");
+    }
+
     public static void printTaskCount() {
-        System.out.println("Now you have " + taskCount + " tasks in the list.");
+        System.out.println("Now you have " + tasks.size() + " tasks in the list.");
     }
 
     public static void printTodoException() {
@@ -42,18 +46,27 @@ public static void printDoneException() {
         System.out.println("The description of done cannot be empty.");
     }
 
+    public static void printDeleteException() {
+        System.out.println("The description of delete cannot be empty.");
+    }
+
     public static void printTaskTypeResponse() {
         //printing different responses depending if its duke.Todo/duke.Deadline/duke.Event
         printGotIt();
-        tasks[taskCount - 1].printTask();
+        tasks.get(tasks.size() - 1).printTask();
         printTaskCount();
     }
 
+    public static void printDeleteResponse() {
+        printRemoveIt();
+        tasks.get(tasks.size() - 1).printTask();
+    }
+
     public static void printList() {
         System.out.println("Here are the tasks in your list:");
-        for (int i = 0; i < taskCount; i += 1) {
+        for (int i = 0; i < tasks.size(); i += 1) {
             System.out.print((i + 1) + ".");
-            tasks[i].printTask();
+            tasks.get(i).printTask();
         }
     }
 
@@ -62,9 +75,9 @@ public static void taskDone(String line) throws DoneException {
             throw new DoneException();
         } else {
             int index = Integer.parseInt(line) - 1;
-            tasks[index].setDone();
+            tasks.get(index).setDone();
             System.out.println("Nice! I've marked this task as done:");
-            tasks[index].printTask();
+            tasks.get(index).printTask();
         }
     }
 
@@ -72,8 +85,7 @@ public static void addTodo(String line) throws TodoException {
         if (line.equals("") || line.equals("todo")) {
             throw new TodoException();
         } else {
-            tasks[taskCount] = new Todo(line);
-            taskCount = taskCount + 1;
+            tasks.add(new Todo (line));
             printTaskTypeResponse();
         }
     }
@@ -85,8 +97,7 @@ public static void addDeadline(String line) throws DeadlineException {
             //extracting the description and date
             String description = line.replaceAll("/.+", "");
             String by = line.replaceAll(".+/by", "");
-            tasks[taskCount] = new Deadline(description, by);
-            taskCount = taskCount + 1;
+            tasks.add(new Deadline (description, by));
             printTaskTypeResponse();
         }
     }
@@ -97,13 +108,23 @@ public static void addEvent(String line) throws EventException {
         } else {
             //extracting the description and date
             String description = line.replaceAll("/.+", "");
-            String by = line.replaceAll(".+/at", "");
-            tasks[taskCount] = new Event(description, by);
-            taskCount = taskCount + 1;
+            String at = line.replaceAll(".+/at", "");
+            tasks.add(new Event (description, at));
             printTaskTypeResponse();
         }
     }
 
+    public static void deleteTask(String line) throws DeleteException {
+        if (line.equals("") || line.equals("delete")) {
+            throw new DeleteException();
+        } else {
+            int index = Integer.parseInt(line) - 1;
+            printDeleteResponse();
+            tasks.remove(index);
+            printTaskCount();
+        }
+    }
+
     public static void readInput(String line) {
         String[] splitLine = line.split(" ", 2);
         String command = splitLine[0];
@@ -135,6 +156,12 @@ public static void readInput(String line) {
             } catch (EventException e) {
                 printEventException();
             }
+        } else if (command.equals("delete")) {
+            try {
+                deleteTask(line);
+            } catch (DeleteException e) {
+                printDeleteException();
+            }
         } else {
             //error with input
             printConfused();
diff --git a/src/main/java/duke/EventException.java b/src/main/java/duke/EventException.java
index b4366936d..1241ce337 100644
--- a/src/main/java/duke/EventException.java
+++ b/src/main/java/duke/EventException.java
@@ -1,4 +1,4 @@
 package duke;
 
-public class EventException extends Exception{
+public class EventException extends Exception {
 }
diff --git a/src/main/java/duke/TaskCountException.java b/src/main/java/duke/TaskCountException.java
index b42b9e248..3662e528a 100644
--- a/src/main/java/duke/TaskCountException.java
+++ b/src/main/java/duke/TaskCountException.java
@@ -1,4 +1,4 @@
 package duke;
 
-public class TaskCountException extends Exception{
+public class TaskCountException extends Exception {
 }
diff --git a/src/main/java/duke/TodoException.java b/src/main/java/duke/TodoException.java
index 66545fe54..541e2220f 100644
--- a/src/main/java/duke/TodoException.java
+++ b/src/main/java/duke/TodoException.java
@@ -1,4 +1,4 @@
 package duke;
 
-public class TodoException extends Exception{
+public class TodoException extends Exception {
 }

From a5faa2b620073871c9489ad814b3394446218758 Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Wed, 15 Sep 2021 01:13:10 +0800
Subject: [PATCH 18/25] Add Level-7

---
 src/main/java/duke/Deadline.java           | 11 +++
 src/main/java/duke/DeadlineException.java  |  2 +-
 src/main/java/duke/DoneException.java      |  2 +-
 src/main/java/duke/Duke.java               | 96 ++++++++++++++++++----
 src/main/java/duke/Event.java              | 10 +++
 src/main/java/duke/EventException.java     |  2 +-
 src/main/java/duke/Task.java               |  9 ++
 src/main/java/duke/TaskCountException.java |  2 +-
 src/main/java/duke/Todo.java               |  8 ++
 src/main/java/duke/TodoException.java      |  2 +-
 10 files changed, 124 insertions(+), 20 deletions(-)

diff --git a/src/main/java/duke/Deadline.java b/src/main/java/duke/Deadline.java
index f8cae570c..6e3fa5fa7 100644
--- a/src/main/java/duke/Deadline.java
+++ b/src/main/java/duke/Deadline.java
@@ -7,9 +7,15 @@ public Deadline(String description, String by) {
         super(description);
         this.by = by;
     }
+    public Deadline(String description, boolean isDone, String by) {
+        super(description, isDone);
+        this.by = by;
+    }
+
     public String getBy() {
         return by;
     }
+
     public void setBy(String by) {
         this.by = by;
     }
@@ -18,4 +24,9 @@ public void printTask() {
         System.out.print("[D][" + getStatusIcon() + "] " + getDescription());
         System.out.println("(by:" + by + ")");
     }
+
+    @Override
+    public String saveTask() {
+        return "D | " + (isDone ? 1 : 0) + " | " + description + " | " + by;
+    }
 }
diff --git a/src/main/java/duke/DeadlineException.java b/src/main/java/duke/DeadlineException.java
index 96eb5dda9..b6c92aff2 100644
--- a/src/main/java/duke/DeadlineException.java
+++ b/src/main/java/duke/DeadlineException.java
@@ -1,4 +1,4 @@
 package duke;
 
-public class DeadlineException extends Exception{
+public class DeadlineException extends Exception {
 }
diff --git a/src/main/java/duke/DoneException.java b/src/main/java/duke/DoneException.java
index 674670a8a..e0512ebec 100644
--- a/src/main/java/duke/DoneException.java
+++ b/src/main/java/duke/DoneException.java
@@ -1,4 +1,4 @@
 package duke;
 
-public class DoneException extends Exception{
+public class DoneException extends Exception {
 }
diff --git a/src/main/java/duke/Duke.java b/src/main/java/duke/Duke.java
index 1e1c36654..d3c4f7514 100644
--- a/src/main/java/duke/Duke.java
+++ b/src/main/java/duke/Duke.java
@@ -1,10 +1,39 @@
 package duke;
 
+import java.util.ArrayList;
 import java.util.Scanner;
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
 
 public class Duke {
-    public static Task[] tasks = new Task[100];
-    public static int taskCount = 0;
+    public static ArrayList<Task> tasks = new ArrayList<>();
+    public static File f = new File("data/duke.txt"); // create a File for the given file path
+
+    public static void loadTasks() throws FileNotFoundException {
+        Scanner s = new Scanner(f); // create a Scanner using the File as the source
+        while (s.hasNext()) {
+            String task = s.nextLine();
+            String[] taskSplit= task.split(" \\| ");
+            String taskType = taskSplit[0];
+            boolean isDone = taskSplit[1].equals("1");
+            String description = taskSplit[2];
+            String preposition = taskSplit.length >= 4 ? taskSplit[3] : "";
+            if (taskType.equals("E")){
+                tasks.add(new Event(description, isDone, preposition));
+            } else if (taskType.equals("D")){
+                tasks.add(new Deadline(description, isDone, preposition));
+
+            } else {
+                tasks.add(new Todo(description, isDone));
+            }
+        }
+    }
 
     public static void printGreeting() {
         System.out.println("Hello! I'm Duke\n" + "What can I do for you?");
@@ -23,7 +52,7 @@ public static void printGotIt() {
     }
 
     public static void printTaskCount() {
-        System.out.println("Now you have " + taskCount + " tasks in the list.");
+        System.out.println("Now you have " + tasks.size() + " tasks in the list.");
     }
 
     public static void printTodoException() {
@@ -45,15 +74,51 @@ public static void printDoneException() {
     public static void printTaskTypeResponse() {
         //printing different responses depending if its duke.Todo/duke.Deadline/duke.Event
         printGotIt();
-        tasks[taskCount - 1].printTask();
+        tasks.get(tasks.size() - 1).printTask();
         printTaskCount();
     }
 
     public static void printList() {
         System.out.println("Here are the tasks in your list:");
-        for (int i = 0; i < taskCount; i += 1) {
+        for (int i = 0; i < tasks.size(); i += 1) {
             System.out.print((i + 1) + ".");
-            tasks[i].printTask();
+            tasks.get(i).printTask();
+        }
+    }
+
+    public static void createFile() throws IOException{
+        Path pathToFile = Paths.get("data/duke.txt");
+        Files.createDirectories(pathToFile.getParent());
+        f.createNewFile();
+    }
+
+    public static void initialiseTasks(){
+        try {
+            loadTasks();
+        } catch (FileNotFoundException e0){
+            System.out.println("The file data/duke.txt is not found.");
+            try {
+                createFile();
+            } catch (IOException e1){
+                System.out.println("There has been an error creating a new file.");
+            }
+            System.out.println("A new file data/duke.txt has been created.");
+        }
+    }
+
+    private static void writeToFile() throws IOException {
+        FileWriter fw = new FileWriter("data/duke.txt");
+        for (Task list : tasks) {
+            fw.write(list.saveTask() + "\n");
+        }
+        fw.close();
+    }
+
+    public static void write() {
+        try {
+            writeToFile();
+        } catch (IOException e) {
+            System.out.println("There has been an error writing to file.");
         }
     }
 
@@ -62,9 +127,9 @@ public static void taskDone(String line) throws DoneException {
             throw new DoneException();
         } else {
             int index = Integer.parseInt(line) - 1;
-            tasks[index].setDone();
+            tasks.get(index).setDone();
             System.out.println("Nice! I've marked this task as done:");
-            tasks[index].printTask();
+            tasks.get(index).printTask();
         }
     }
 
@@ -72,9 +137,9 @@ public static void addTodo(String line) throws TodoException {
         if (line.equals("") || line.equals("todo")) {
             throw new TodoException();
         } else {
-            tasks[taskCount] = new Todo(line);
-            taskCount = taskCount + 1;
+            tasks.add(new Todo(line));
             printTaskTypeResponse();
+            write();
         }
     }
 
@@ -85,9 +150,9 @@ public static void addDeadline(String line) throws DeadlineException {
             //extracting the description and date
             String description = line.replaceAll("/.+", "");
             String by = line.replaceAll(".+/by", "");
-            tasks[taskCount] = new Deadline(description, by);
-            taskCount = taskCount + 1;
+            tasks.add(new Deadline (description, by));
             printTaskTypeResponse();
+            write();
         }
     }
 
@@ -97,10 +162,10 @@ public static void addEvent(String line) throws EventException {
         } else {
             //extracting the description and date
             String description = line.replaceAll("/.+", "");
-            String by = line.replaceAll(".+/at", "");
-            tasks[taskCount] = new Event(description, by);
-            taskCount = taskCount + 1;
+            String at = line.replaceAll(".+/at", "");
+            tasks.add(new Event (description, at));
             printTaskTypeResponse();
+            write();
         }
     }
 
@@ -142,6 +207,7 @@ public static void readInput(String line) {
     }
 
     public static void main(String[] args) {
+        initialiseTasks();
         printGreeting();
         String line;
         Scanner in = new Scanner(System.in);
diff --git a/src/main/java/duke/Event.java b/src/main/java/duke/Event.java
index df8c6a880..720852d68 100644
--- a/src/main/java/duke/Event.java
+++ b/src/main/java/duke/Event.java
@@ -7,6 +7,11 @@ public Event(String description, String at) {
         super(description);
         this.at = at;
     }
+
+    public Event(String description, boolean isDone, String at) {
+        super(description, isDone);
+        this.at = at;
+    }
     public String getAt() {
         return at;
     }
@@ -18,4 +23,9 @@ public void printTask() {
         System.out.print("[E][" + getStatusIcon() + "] " + getDescription());
         System.out.println("(at:" + at + ")");
     }
+
+    @Override
+    public String saveTask() {
+        return "E | " + (isDone ? 1 : 0) + " | " + description + " | " + at;
+    }
 }
diff --git a/src/main/java/duke/EventException.java b/src/main/java/duke/EventException.java
index b4366936d..1241ce337 100644
--- a/src/main/java/duke/EventException.java
+++ b/src/main/java/duke/EventException.java
@@ -1,4 +1,4 @@
 package duke;
 
-public class EventException extends Exception{
+public class EventException extends Exception {
 }
diff --git a/src/main/java/duke/Task.java b/src/main/java/duke/Task.java
index 8c6172d16..061f21fa8 100644
--- a/src/main/java/duke/Task.java
+++ b/src/main/java/duke/Task.java
@@ -9,6 +9,11 @@ public Task(String description) {
         isDone = false;
     }
 
+    public Task(String description, boolean isDone) {
+        this.description = description;
+        this.isDone = isDone;
+    }
+
     public String getStatusIcon() {
         // mark done task with X
         return (isDone ? "X" : " ");
@@ -25,4 +30,8 @@ public void setDone() {
     public void printTask() {
         System.out.println(description);
     }
+
+    public String saveTask() {
+        return null;
+    }
 }
diff --git a/src/main/java/duke/TaskCountException.java b/src/main/java/duke/TaskCountException.java
index b42b9e248..3662e528a 100644
--- a/src/main/java/duke/TaskCountException.java
+++ b/src/main/java/duke/TaskCountException.java
@@ -1,4 +1,4 @@
 package duke;
 
-public class TaskCountException extends Exception{
+public class TaskCountException extends Exception {
 }
diff --git a/src/main/java/duke/Todo.java b/src/main/java/duke/Todo.java
index 80195adbc..3001483b5 100644
--- a/src/main/java/duke/Todo.java
+++ b/src/main/java/duke/Todo.java
@@ -5,8 +5,16 @@ public class Todo extends Task{
     public Todo(String description) {
         super(description);
     }
+    public Todo(String description, boolean isDone) {
+        super(description, isDone);
+    }
 
     public void printTask() {
         System.out.println("[T][" + getStatusIcon() + "] " + getDescription());
     }
+
+    @Override
+    public String saveTask() {
+        return "T | " + (isDone ? 1 : 0) + " | " + description;
+    }
 }
diff --git a/src/main/java/duke/TodoException.java b/src/main/java/duke/TodoException.java
index 66545fe54..541e2220f 100644
--- a/src/main/java/duke/TodoException.java
+++ b/src/main/java/duke/TodoException.java
@@ -1,4 +1,4 @@
 package duke;
 
-public class TodoException extends Exception{
+public class TodoException extends Exception {
 }

From d17bf947c9c6b72f091728af7888aee2102077df Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Wed, 15 Sep 2021 01:20:58 +0800
Subject: [PATCH 19/25] Additional resolving of merge conflicts

---
 src/main/java/duke/Duke.java | 11 +----------
 1 file changed, 1 insertion(+), 10 deletions(-)

diff --git a/src/main/java/duke/Duke.java b/src/main/java/duke/Duke.java
index 95ffd4df5..2a1d01df2 100644
--- a/src/main/java/duke/Duke.java
+++ b/src/main/java/duke/Duke.java
@@ -13,8 +13,6 @@
 
 public class Duke {
     public static ArrayList<Task> tasks = new ArrayList<>();
-<<<<<<< HEAD
-=======
     public static File f = new File("data/duke.txt"); // create a File for the given file path
 
     public static void loadTasks() throws FileNotFoundException {
@@ -36,7 +34,6 @@ public static void loadTasks() throws FileNotFoundException {
             }
         }
     }
->>>>>>> branch-Level-7
 
     public static void printGreeting() {
         System.out.println("Hello! I'm Duke\n" + "What can I do for you?");
@@ -99,8 +96,7 @@ public static void printList() {
         for (int i = 0; i < tasks.size(); i += 1) {
             System.out.print((i + 1) + ".");
             tasks.get(i).printTask();
-<<<<<<< HEAD
-=======
+
         }
     }
 
@@ -137,7 +133,6 @@ public static void write() {
             writeToFile();
         } catch (IOException e) {
             System.out.println("There has been an error writing to file.");
->>>>>>> branch-Level-7
         }
     }
 
@@ -156,11 +151,7 @@ public static void addTodo(String line) throws TodoException {
         if (line.equals("") || line.equals("todo")) {
             throw new TodoException();
         } else {
-<<<<<<< HEAD
-            tasks.add(new Todo (line));
-=======
             tasks.add(new Todo(line));
->>>>>>> branch-Level-7
             printTaskTypeResponse();
             write();
         }

From 890f18e8137ed45a42066e81d5953e3978372d73 Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Sun, 26 Sep 2021 00:01:00 +0800
Subject: [PATCH 20/25] Bug fixes

---
 data/duke.txt                                 |  0
 src/main/java/META-INF/MANIFEST.MF            |  3 +
 src/main/java/duke/Duke.java                  | 78 ++++++++++++++-----
 src/main/java/duke/TaskCountException.java    |  4 -
 .../{ => exceptions}/DeadlineException.java   |  2 +-
 .../{ => exceptions}/DeleteException.java     |  2 +-
 .../duke/exceptions/DeleteRangeException.java |  4 +
 .../duke/{ => exceptions}/DoneException.java  |  2 +-
 .../duke/exceptions/DoneRangeException.java   |  4 +
 .../duke/exceptions/EmptyListException.java   |  4 +
 .../duke/{ => exceptions}/EventException.java |  2 +-
 .../duke/{ => exceptions}/TodoException.java  |  2 +-
 src/main/java/duke/{ => tasks}/Deadline.java  |  4 +-
 src/main/java/duke/{ => tasks}/Event.java     |  2 +-
 src/main/java/duke/{ => tasks}/Task.java      |  2 +-
 src/main/java/duke/{ => tasks}/Todo.java      |  2 +-
 16 files changed, 83 insertions(+), 34 deletions(-)
 create mode 100644 data/duke.txt
 create mode 100644 src/main/java/META-INF/MANIFEST.MF
 delete mode 100644 src/main/java/duke/TaskCountException.java
 rename src/main/java/duke/{ => exceptions}/DeadlineException.java (68%)
 rename src/main/java/duke/{ => exceptions}/DeleteException.java (67%)
 create mode 100644 src/main/java/duke/exceptions/DeleteRangeException.java
 rename src/main/java/duke/{ => exceptions}/DoneException.java (66%)
 create mode 100644 src/main/java/duke/exceptions/DoneRangeException.java
 create mode 100644 src/main/java/duke/exceptions/EmptyListException.java
 rename src/main/java/duke/{ => exceptions}/EventException.java (67%)
 rename src/main/java/duke/{ => exceptions}/TodoException.java (66%)
 rename src/main/java/duke/{ => tasks}/Deadline.java (92%)
 rename src/main/java/duke/{ => tasks}/Event.java (97%)
 rename src/main/java/duke/{ => tasks}/Task.java (97%)
 rename src/main/java/duke/{ => tasks}/Todo.java (95%)

diff --git a/data/duke.txt b/data/duke.txt
new file mode 100644
index 000000000..e69de29bb
diff --git a/src/main/java/META-INF/MANIFEST.MF b/src/main/java/META-INF/MANIFEST.MF
new file mode 100644
index 000000000..2c9a9745c
--- /dev/null
+++ b/src/main/java/META-INF/MANIFEST.MF
@@ -0,0 +1,3 @@
+Manifest-Version: 1.0
+Main-Class: duke.Duke
+
diff --git a/src/main/java/duke/Duke.java b/src/main/java/duke/Duke.java
index 2a1d01df2..49404d5cb 100644
--- a/src/main/java/duke/Duke.java
+++ b/src/main/java/duke/Duke.java
@@ -1,5 +1,18 @@
 package duke;
 
+import duke.exceptions.DeleteRangeException;
+import duke.exceptions.DoneRangeException;
+import duke.exceptions.EmptyListException;
+import duke.exceptions.DoneException;
+import duke.exceptions.DeleteException;
+import duke.exceptions.DeadlineException;
+import duke.exceptions.EventException;
+import duke.exceptions.TodoException;
+import duke.tasks.Deadline;
+import duke.tasks.Event;
+import duke.tasks.Task;
+import duke.tasks.Todo;
+
 import java.util.ArrayList;
 import java.util.Scanner;
 import java.io.File;
@@ -72,15 +85,23 @@ public static void printEventException() {
     }
 
     public static void printDoneException() {
-        System.out.println("The description of done cannot be empty.");
+        System.out.println("The description of done must be a number from the task list.");
+    }
+
+    public static void printRangeException() {
+        System.out.println("That task does not exist.");
     }
 
     public static void printDeleteException() {
-        System.out.println("The description of delete cannot be empty.");
+        System.out.println("The description of delete must be a number from the task list.");
+    }
+
+    public static void printEmptyListException() {
+        System.out.println("The list is empty.");
     }
 
     public static void printTaskTypeResponse() {
-        //printing different responses depending if its duke.Todo/duke.Deadline/duke.Event
+        //printing different responses depending if its duke.tasks.Todo/duke.tasks.Deadline/duke.tasks.Event
         printGotIt();
         tasks.get(tasks.size() - 1).printTask();
         printTaskCount();
@@ -91,22 +112,25 @@ public static void printDeleteResponse() {
         tasks.get(tasks.size() - 1).printTask();
     }
 
-    public static void printList() {
-        System.out.println("Here are the tasks in your list:");
-        for (int i = 0; i < tasks.size(); i += 1) {
-            System.out.print((i + 1) + ".");
-            tasks.get(i).printTask();
-
+    public static void printList() throws EmptyListException {
+        if (tasks.size() == 0) {
+            throw new EmptyListException();
+        } else {
+            System.out.println("Here are the tasks in your list:");
+            for (int i = 0; i < tasks.size(); i += 1) {
+                System.out.print((i + 1) + ".");
+                tasks.get(i).printTask();
+            }
         }
     }
 
-    public static void createFile() throws IOException{
+    public static void createFile() throws IOException {
         Path pathToFile = Paths.get("data/duke.txt");
         Files.createDirectories(pathToFile.getParent());
         f.createNewFile();
     }
 
-    public static void initialiseTasks(){
+    public static void initialiseTasks() {
         try {
             loadTasks();
         } catch (FileNotFoundException e0){
@@ -136,11 +160,14 @@ public static void write() {
         }
     }
 
-    public static void taskDone(String line) throws DoneException {
-        if (line.equals("") || line.equals("done")) {
+    public static void taskDone(String line) throws DoneException, DoneRangeException {
+        if (!line.matches("\\d+")) {
             throw new DoneException();
+        }
+        int index = Integer.parseInt(line) - 1;
+        if (index >= tasks.size()) {
+            throw new DoneRangeException();
         } else {
-            int index = Integer.parseInt(line) - 1;
             tasks.get(index).setDone();
             System.out.println("Nice! I've marked this task as done:");
             tasks.get(index).printTask();
@@ -164,7 +191,7 @@ public static void addDeadline(String line) throws DeadlineException {
             //extracting the description and date
             String description = line.replaceAll("/.+", "");
             String by = line.replaceAll(".+/by", "");
-            tasks.add(new Deadline (description, by));
+            tasks.add(new Deadline(description, by));
             printTaskTypeResponse();
             write();
         }
@@ -177,17 +204,20 @@ public static void addEvent(String line) throws EventException {
             //extracting the description and date
             String description = line.replaceAll("/.+", "");
             String at = line.replaceAll(".+/at", "");
-            tasks.add(new Event (description, at));
+            tasks.add(new Event(description, at));
             printTaskTypeResponse();
             write();
         }
     }
 
-    public static void deleteTask(String line) throws DeleteException {
-        if (line.equals("") || line.equals("delete")) {
+    public static void deleteTask(String line) throws DeleteException, DeleteRangeException {
+        if (!line.matches("\\d+")) {
             throw new DeleteException();
+        }
+        int index = Integer.parseInt(line) - 1;
+        if (index >= tasks.size()) {
+            throw new DeleteRangeException();
         } else {
-            int index = Integer.parseInt(line) - 1;
             printDeleteResponse();
             tasks.remove(index);
             printTaskCount();
@@ -199,13 +229,19 @@ public static void readInput(String line) {
         String command = splitLine[0];
         line = line.replaceAll("^" + command + " ", "");
         if (command.equals("list")) {
-            printList();
+            try {
+                printList();
+            } catch (EmptyListException e) {
+                printEmptyListException();
+            }
         } else if (command.equals("done")) {
             try {
                 //find which task user is done with
                 taskDone(line);
             } catch (DoneException e) {
                 printDoneException();
+            } catch (DoneRangeException e) {
+                printRangeException();
             }
         } else if (command.equals("todo")) {
             try {
@@ -230,6 +266,8 @@ public static void readInput(String line) {
                 deleteTask(line);
             } catch (DeleteException e) {
                 printDeleteException();
+            } catch (DeleteRangeException e) {
+                printRangeException();
             }
         } else {
             //error with input
diff --git a/src/main/java/duke/TaskCountException.java b/src/main/java/duke/TaskCountException.java
deleted file mode 100644
index 3662e528a..000000000
--- a/src/main/java/duke/TaskCountException.java
+++ /dev/null
@@ -1,4 +0,0 @@
-package duke;
-
-public class TaskCountException extends Exception {
-}
diff --git a/src/main/java/duke/DeadlineException.java b/src/main/java/duke/exceptions/DeadlineException.java
similarity index 68%
rename from src/main/java/duke/DeadlineException.java
rename to src/main/java/duke/exceptions/DeadlineException.java
index b6c92aff2..bee2449a1 100644
--- a/src/main/java/duke/DeadlineException.java
+++ b/src/main/java/duke/exceptions/DeadlineException.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.exceptions;
 
 public class DeadlineException extends Exception {
 }
diff --git a/src/main/java/duke/DeleteException.java b/src/main/java/duke/exceptions/DeleteException.java
similarity index 67%
rename from src/main/java/duke/DeleteException.java
rename to src/main/java/duke/exceptions/DeleteException.java
index baea749ed..f03a5e128 100644
--- a/src/main/java/duke/DeleteException.java
+++ b/src/main/java/duke/exceptions/DeleteException.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.exceptions;
 
 public class DeleteException extends Exception {
 }
diff --git a/src/main/java/duke/exceptions/DeleteRangeException.java b/src/main/java/duke/exceptions/DeleteRangeException.java
new file mode 100644
index 000000000..09eab86a7
--- /dev/null
+++ b/src/main/java/duke/exceptions/DeleteRangeException.java
@@ -0,0 +1,4 @@
+package duke.exceptions;
+
+public class DeleteRangeException extends Exception {
+}
diff --git a/src/main/java/duke/DoneException.java b/src/main/java/duke/exceptions/DoneException.java
similarity index 66%
rename from src/main/java/duke/DoneException.java
rename to src/main/java/duke/exceptions/DoneException.java
index e0512ebec..c5f747d57 100644
--- a/src/main/java/duke/DoneException.java
+++ b/src/main/java/duke/exceptions/DoneException.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.exceptions;
 
 public class DoneException extends Exception {
 }
diff --git a/src/main/java/duke/exceptions/DoneRangeException.java b/src/main/java/duke/exceptions/DoneRangeException.java
new file mode 100644
index 000000000..1c9f4b5a1
--- /dev/null
+++ b/src/main/java/duke/exceptions/DoneRangeException.java
@@ -0,0 +1,4 @@
+package duke.exceptions;
+
+public class DoneRangeException extends Exception {
+}
diff --git a/src/main/java/duke/exceptions/EmptyListException.java b/src/main/java/duke/exceptions/EmptyListException.java
new file mode 100644
index 000000000..f9e6a4248
--- /dev/null
+++ b/src/main/java/duke/exceptions/EmptyListException.java
@@ -0,0 +1,4 @@
+package duke.exceptions;
+
+public class EmptyListException extends Exception {
+}
diff --git a/src/main/java/duke/EventException.java b/src/main/java/duke/exceptions/EventException.java
similarity index 67%
rename from src/main/java/duke/EventException.java
rename to src/main/java/duke/exceptions/EventException.java
index 1241ce337..7dde535d8 100644
--- a/src/main/java/duke/EventException.java
+++ b/src/main/java/duke/exceptions/EventException.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.exceptions;
 
 public class EventException extends Exception {
 }
diff --git a/src/main/java/duke/TodoException.java b/src/main/java/duke/exceptions/TodoException.java
similarity index 66%
rename from src/main/java/duke/TodoException.java
rename to src/main/java/duke/exceptions/TodoException.java
index 541e2220f..0ab691e07 100644
--- a/src/main/java/duke/TodoException.java
+++ b/src/main/java/duke/exceptions/TodoException.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.exceptions;
 
 public class TodoException extends Exception {
 }
diff --git a/src/main/java/duke/Deadline.java b/src/main/java/duke/tasks/Deadline.java
similarity index 92%
rename from src/main/java/duke/Deadline.java
rename to src/main/java/duke/tasks/Deadline.java
index 6e3fa5fa7..4ce536a06 100644
--- a/src/main/java/duke/Deadline.java
+++ b/src/main/java/duke/tasks/Deadline.java
@@ -1,6 +1,6 @@
-package duke;
+package duke.tasks;
 
-public class Deadline extends Todo{
+public class Deadline extends Todo {
     protected String by;
 
     public Deadline(String description, String by) {
diff --git a/src/main/java/duke/Event.java b/src/main/java/duke/tasks/Event.java
similarity index 97%
rename from src/main/java/duke/Event.java
rename to src/main/java/duke/tasks/Event.java
index 720852d68..c92dc384d 100644
--- a/src/main/java/duke/Event.java
+++ b/src/main/java/duke/tasks/Event.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.tasks;
 
 public class Event extends Todo{
     protected String at;
diff --git a/src/main/java/duke/Task.java b/src/main/java/duke/tasks/Task.java
similarity index 97%
rename from src/main/java/duke/Task.java
rename to src/main/java/duke/tasks/Task.java
index 061f21fa8..4a11cf0e9 100644
--- a/src/main/java/duke/Task.java
+++ b/src/main/java/duke/tasks/Task.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.tasks;
 
 public class Task {
     protected String description;
diff --git a/src/main/java/duke/Todo.java b/src/main/java/duke/tasks/Todo.java
similarity index 95%
rename from src/main/java/duke/Todo.java
rename to src/main/java/duke/tasks/Todo.java
index 3001483b5..b47b86345 100644
--- a/src/main/java/duke/Todo.java
+++ b/src/main/java/duke/tasks/Todo.java
@@ -1,4 +1,4 @@
-package duke;
+package duke.tasks;
 
 public class Todo extends Task{
 

From 43da2b2937d7746ec137cb1fc973e2c6e116aed2 Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Mon, 27 Sep 2021 04:19:18 +0800
Subject: [PATCH 21/25] A-MoreOOP

---
 src/main/java/duke/Duke.java                  | 306 +++---------------
 src/main/java/duke/Parser.java                |  41 +++
 src/main/java/duke/Storage.java               |  95 ++++++
 src/main/java/duke/Ui.java                    |  23 ++
 src/main/java/duke/commands/AddCommand.java   |  29 ++
 src/main/java/duke/commands/Command.java      |  15 +
 .../java/duke/commands/CommandOutput.java     |  33 ++
 .../java/duke/commands/DeleteCommand.java     |  15 +
 src/main/java/duke/commands/DoneCommand.java  |  15 +
 src/main/java/duke/commands/ListCommand.java  |  15 +
 src/main/java/duke/commands/NoCommand.java    |  15 +
 .../duke/exceptions/AlreadyDoneException.java |  10 +
 .../duke/exceptions/DeadlineException.java    |   6 +
 .../java/duke/exceptions/DeleteException.java |   4 -
 .../exceptions/DeleteFormatException.java     |  10 +
 .../duke/exceptions/DeleteRangeException.java |   6 +
 .../java/duke/exceptions/DoneException.java   |   4 -
 .../duke/exceptions/DoneFormatException.java  |  10 +
 .../duke/exceptions/DoneRangeException.java   |   6 +
 .../java/duke/exceptions/EmptyException.java  |  10 +
 .../duke/exceptions/EmptyListException.java   |   6 +
 .../java/duke/exceptions/EventException.java  |   6 +
 .../duke/exceptions/FileFormatException.java  |   4 +
 .../java/duke/exceptions/TodoException.java   |   6 +
 src/main/java/duke/tasks/Deadline.java        |   9 +-
 src/main/java/duke/tasks/Event.java           |   9 +-
 src/main/java/duke/tasks/Task.java            |   8 +-
 src/main/java/duke/tasks/TaskList.java        | 107 ++++++
 .../java/duke/tasks/TaskListResponse.java     |  13 +
 src/main/java/duke/tasks/TaskType.java        |   5 +
 src/main/java/duke/tasks/Todo.java            |   6 +-
 text-ui-test/EXPECTED.TXT                     |  32 +-
 text-ui-test/input.txt                        |   1 +
 33 files changed, 580 insertions(+), 300 deletions(-)
 create mode 100644 src/main/java/duke/Parser.java
 create mode 100644 src/main/java/duke/Storage.java
 create mode 100644 src/main/java/duke/Ui.java
 create mode 100644 src/main/java/duke/commands/AddCommand.java
 create mode 100644 src/main/java/duke/commands/Command.java
 create mode 100644 src/main/java/duke/commands/CommandOutput.java
 create mode 100644 src/main/java/duke/commands/DeleteCommand.java
 create mode 100644 src/main/java/duke/commands/DoneCommand.java
 create mode 100644 src/main/java/duke/commands/ListCommand.java
 create mode 100644 src/main/java/duke/commands/NoCommand.java
 create mode 100644 src/main/java/duke/exceptions/AlreadyDoneException.java
 delete mode 100644 src/main/java/duke/exceptions/DeleteException.java
 create mode 100644 src/main/java/duke/exceptions/DeleteFormatException.java
 delete mode 100644 src/main/java/duke/exceptions/DoneException.java
 create mode 100644 src/main/java/duke/exceptions/DoneFormatException.java
 create mode 100644 src/main/java/duke/exceptions/EmptyException.java
 create mode 100644 src/main/java/duke/exceptions/FileFormatException.java
 create mode 100644 src/main/java/duke/tasks/TaskList.java
 create mode 100644 src/main/java/duke/tasks/TaskListResponse.java
 create mode 100644 src/main/java/duke/tasks/TaskType.java

diff --git a/src/main/java/duke/Duke.java b/src/main/java/duke/Duke.java
index 49404d5cb..1df3de12b 100644
--- a/src/main/java/duke/Duke.java
+++ b/src/main/java/duke/Duke.java
@@ -1,291 +1,57 @@
 package duke;
 
-import duke.exceptions.DeleteRangeException;
-import duke.exceptions.DoneRangeException;
-import duke.exceptions.EmptyListException;
-import duke.exceptions.DoneException;
-import duke.exceptions.DeleteException;
-import duke.exceptions.DeadlineException;
-import duke.exceptions.EventException;
-import duke.exceptions.TodoException;
-import duke.tasks.Deadline;
-import duke.tasks.Event;
-import duke.tasks.Task;
-import duke.tasks.Todo;
+import duke.commands.Command;
+import duke.commands.CommandOutput;
+import duke.tasks.*;
 
-import java.util.ArrayList;
 import java.util.Scanner;
-import java.io.File;
-import java.io.FileNotFoundException;
-import java.io.FileWriter;
-import java.io.IOException;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.nio.file.Paths;
-
 
 public class Duke {
-    public static ArrayList<Task> tasks = new ArrayList<>();
-    public static File f = new File("data/duke.txt"); // create a File for the given file path
-
-    public static void loadTasks() throws FileNotFoundException {
-        Scanner s = new Scanner(f); // create a Scanner using the File as the source
-        while (s.hasNext()) {
-            String task = s.nextLine();
-            String[] taskSplit= task.split(" \\| ");
-            String taskType = taskSplit[0];
-            boolean isDone = taskSplit[1].equals("1");
-            String description = taskSplit[2];
-            String preposition = taskSplit.length >= 4 ? taskSplit[3] : "";
-            if (taskType.equals("E")){
-                tasks.add(new Event(description, isDone, preposition));
-            } else if (taskType.equals("D")){
-                tasks.add(new Deadline(description, isDone, preposition));
-
-            } else {
-                tasks.add(new Todo(description, isDone));
-            }
-        }
-    }
-
-    public static void printGreeting() {
-        System.out.println("Hello! I'm Duke\n" + "What can I do for you?");
-    }
-
-    public static void printConfused() {
-        System.out.println("Could you say that again?");
-    }
-
-    public static void printExit() {
-        System.out.println("Bye. Hope to see you again soon!");
-    }
-
-    public static void printGotIt() {
-        System.out.println("Got it. I've added this task:");
-    }
-
-    public static void printRemoveIt() {
-        System.out.println("Noted. I've removed this task:");
-    }
-
-    public static void printTaskCount() {
-        System.out.println("Now you have " + tasks.size() + " tasks in the list.");
-    }
-
-    public static void printTodoException() {
-        System.out.println("The description of todo cannot be empty.");
-    }
 
-    public static void printDeadlineException() {
-        System.out.println("The description of deadline cannot be empty.");
-    }
-
-    public static void printEventException() {
-        System.out.println("The description of event cannot be empty.");
-    }
-
-    public static void printDoneException() {
-        System.out.println("The description of done must be a number from the task list.");
-    }
-
-    public static void printRangeException() {
-        System.out.println("That task does not exist.");
-    }
-
-    public static void printDeleteException() {
-        System.out.println("The description of delete must be a number from the task list.");
-    }
-
-    public static void printEmptyListException() {
-        System.out.println("The list is empty.");
-    }
-
-    public static void printTaskTypeResponse() {
-        //printing different responses depending if its duke.tasks.Todo/duke.tasks.Deadline/duke.tasks.Event
-        printGotIt();
-        tasks.get(tasks.size() - 1).printTask();
-        printTaskCount();
-    }
-
-    public static void printDeleteResponse() {
-        printRemoveIt();
-        tasks.get(tasks.size() - 1).printTask();
-    }
-
-    public static void printList() throws EmptyListException {
-        if (tasks.size() == 0) {
-            throw new EmptyListException();
-        } else {
-            System.out.println("Here are the tasks in your list:");
-            for (int i = 0; i < tasks.size(); i += 1) {
-                System.out.print((i + 1) + ".");
-                tasks.get(i).printTask();
-            }
-        }
-    }
+    private Storage storage;
+    private TaskList tasks;
+    private Ui ui;
+    private Parser parser;
 
-    public static void createFile() throws IOException {
-        Path pathToFile = Paths.get("data/duke.txt");
-        Files.createDirectories(pathToFile.getParent());
-        f.createNewFile();
+    public Duke(String filePath) {
+        ui = new Ui();
+        storage = new Storage(filePath);
+        parser = new Parser();
+        TaskListResponse response = storage.initialiseTasks();
+        tasks = response.taskList;
+        Ui.printMessage(response.response);
     }
 
-    public static void initialiseTasks() {
+    public CommandOutput executeCommand(Command command) {
         try {
-            loadTasks();
-        } catch (FileNotFoundException e0){
-            System.out.println("The file data/duke.txt is not found.");
-            try {
-                createFile();
-            } catch (IOException e1){
-                System.out.println("There has been an error creating a new file.");
-            }
-            System.out.println("A new file data/duke.txt has been created.");
-        }
-    }
-
-    private static void writeToFile() throws IOException {
-        FileWriter fw = new FileWriter("data/duke.txt");
-        for (Task list : tasks) {
-            fw.write(list.saveTask() + "\n");
-        }
-        fw.close();
-    }
-
-    public static void write() {
-        try {
-            writeToFile();
-        } catch (IOException e) {
-            System.out.println("There has been an error writing to file.");
-        }
-    }
-
-    public static void taskDone(String line) throws DoneException, DoneRangeException {
-        if (!line.matches("\\d+")) {
-            throw new DoneException();
-        }
-        int index = Integer.parseInt(line) - 1;
-        if (index >= tasks.size()) {
-            throw new DoneRangeException();
-        } else {
-            tasks.get(index).setDone();
-            System.out.println("Nice! I've marked this task as done:");
-            tasks.get(index).printTask();
-        }
-    }
-
-    public static void addTodo(String line) throws TodoException {
-        if (line.equals("") || line.equals("todo")) {
-            throw new TodoException();
-        } else {
-            tasks.add(new Todo(line));
-            printTaskTypeResponse();
-            write();
-        }
-    }
-
-    public static void addDeadline(String line) throws DeadlineException {
-        if (!line.matches("(.*)/by(.*)")) {
-            throw new DeadlineException();
-        } else {
-            //extracting the description and date
-            String description = line.replaceAll("/.+", "");
-            String by = line.replaceAll(".+/by", "");
-            tasks.add(new Deadline(description, by));
-            printTaskTypeResponse();
-            write();
-        }
-    }
-
-    public static void addEvent(String line) throws EventException {
-        if (!line.matches("(.*)/at(.*)")) {
-            throw new EventException();
-        } else {
-            //extracting the description and date
-            String description = line.replaceAll("/.+", "");
-            String at = line.replaceAll(".+/at", "");
-            tasks.add(new Event(description, at));
-            printTaskTypeResponse();
-            write();
-        }
-    }
-
-    public static void deleteTask(String line) throws DeleteException, DeleteRangeException {
-        if (!line.matches("\\d+")) {
-            throw new DeleteException();
-        }
-        int index = Integer.parseInt(line) - 1;
-        if (index >= tasks.size()) {
-            throw new DeleteRangeException();
-        } else {
-            printDeleteResponse();
-            tasks.remove(index);
-            printTaskCount();
+                return command.execute();
+        } catch (Exception e){
+            return new CommandOutput(e.getMessage(), false, null);
         }
     }
 
-    public static void readInput(String line) {
-        String[] splitLine = line.split(" ", 2);
-        String command = splitLine[0];
-        line = line.replaceAll("^" + command + " ", "");
-        if (command.equals("list")) {
-            try {
-                printList();
-            } catch (EmptyListException e) {
-                printEmptyListException();
-            }
-        } else if (command.equals("done")) {
-            try {
-                //find which task user is done with
-                taskDone(line);
-            } catch (DoneException e) {
-                printDoneException();
-            } catch (DoneRangeException e) {
-                printRangeException();
-            }
-        } else if (command.equals("todo")) {
-            try {
-                addTodo(line);
-            } catch (TodoException e) {
-                printTodoException();
-            }
-        } else if (command.equals("deadline")) {
-            try {
-                addDeadline(line);
-            } catch (DeadlineException e) {
-                printDeadlineException();
-            }
-        } else if (command.equals("event")) {
-            try {
-                addEvent(line);
-            } catch (EventException e) {
-                printEventException();
-            }
-        } else if (command.equals("delete")) {
-            try {
-                deleteTask(line);
-            } catch (DeleteException e) {
-                printDeleteException();
-            } catch (DeleteRangeException e) {
-                printRangeException();
-            }
-        } else {
-            //error with input
-            printConfused();
-        }
-    }
-
-    public static void main(String[] args) {
-        initialiseTasks();
-        printGreeting();
+    public void run() {
+        ui.printGreeting();
         String line;
         Scanner in = new Scanner(System.in);
+        ui.printPrompt();
         line = in.nextLine();
-        //continue to run program unless types "bye" to exit program
-        while(!line.equals("bye")) {
-            readInput(line);
+        while(!line.equals(parser.BYE)) {
+            Command command = parser.parseCommand(tasks, line);
+            CommandOutput commandOutput = executeCommand(command);
+            if (commandOutput.isUpdated()) {
+                tasks = commandOutput.getTaskList();
+                String errorMessage = storage.write(tasks);
+                ui.printMessage(errorMessage);
+            }
+            ui.printMessage(commandOutput.getResponse());
+            ui.printPrompt();
             line = in.nextLine();
         }
-        printExit();
+        ui.printExit();
+    }
+
+    public static void main(String[] args) {
+        new Duke("data/duke.txt").run();
     }
 }
diff --git a/src/main/java/duke/Parser.java b/src/main/java/duke/Parser.java
new file mode 100644
index 000000000..ebad1c37f
--- /dev/null
+++ b/src/main/java/duke/Parser.java
@@ -0,0 +1,41 @@
+package duke;
+
+import duke.commands.Command;
+import duke.commands.ListCommand;
+import duke.commands.AddCommand;
+import duke.commands.NoCommand;
+import duke.commands.DoneCommand;
+import duke.commands.DeleteCommand;
+import duke.tasks.TaskList;
+import duke.tasks.TaskType;
+
+public class Parser {
+
+    public final String LIST = "list";
+    public final String TODO = "todo";
+    public final String DEADLINE = "deadline";
+    public final String EVENT = "event";
+    public final String DONE = "done";
+    public final String DELETE = "delete";
+    public final String BYE = "bye";
+
+    public Command parseCommand(TaskList taskList, String line) {
+        final String[] splitLine = line.split(" ", 2);
+        final String command = splitLine[0];
+        final String userCommand = line.replaceAll("^" + command + " ", "");
+        if (command.equals(LIST)) {
+            return new ListCommand(taskList);
+        } else if (command.equals(TODO)) {
+            return new AddCommand(taskList, userCommand, TaskType.TODO);
+        } else if (command.equals(DEADLINE)) {
+            return new AddCommand(taskList, userCommand, TaskType.DEADLINE);
+        } else if (command.equals(EVENT)) {
+            return new AddCommand(taskList, userCommand, TaskType.EVENT);
+        } else if (command.equals(DONE)) {
+            return new DoneCommand(taskList, userCommand);
+        } else if (command.equals(DELETE)) {
+            return new DeleteCommand(taskList, userCommand);
+        }
+        return new NoCommand(taskList);
+    }
+}
diff --git a/src/main/java/duke/Storage.java b/src/main/java/duke/Storage.java
new file mode 100644
index 000000000..3fc7da82a
--- /dev/null
+++ b/src/main/java/duke/Storage.java
@@ -0,0 +1,95 @@
+package duke;
+
+import duke.exceptions.FileFormatException;
+import duke.tasks.Deadline;
+import duke.tasks.Event;
+import duke.tasks.Task;
+import duke.tasks.Todo;
+import duke.tasks.TaskList;
+import duke.tasks.TaskListResponse;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.Scanner;
+
+public class Storage {
+
+    private final String filePath;
+    private final File f;
+
+    public Storage(String filePath) {
+        this.filePath = filePath;
+        this.f = new File(filePath);
+    }
+
+    public void loadTasks(TaskList taskList) throws FileNotFoundException, FileFormatException {
+        Scanner s = new Scanner(f); // create a Scanner using the File as the source
+        while (s.hasNext()) {
+            String task = s.nextLine();
+            if (!task.matches("T\\s\\|\\s[01]\\s\\|.+")
+                    && !task.matches("[ED]\\\\s\\\\|\\\\s[01]\\\\s\\\\|.+\\\\|.+")) {
+                throw new FileFormatException();
+            }
+            String[] taskSplit= task.split(" \\| ");
+            String taskType = taskSplit[0];
+            boolean isDone = taskSplit[1].equals("1");
+            String description = taskSplit[2];
+            String preposition = taskSplit.length >= 4 ? taskSplit[3] : "";
+            if (taskType.equals("E")){
+                taskList.tasks.add(new Event(description, isDone, preposition));
+            } else if (taskType.equals("D")){
+                taskList.tasks.add(new Deadline(description, isDone, preposition));
+            } else {
+                taskList.tasks.add(new Todo(description, isDone));
+            }
+        }
+    }
+
+    public void createFile() throws IOException {
+        Path pathToFile = Paths.get("data/duke.txt");
+        Files.createDirectories(pathToFile.getParent());
+        f.createNewFile();
+    }
+
+    public TaskListResponse initialiseTasks() {
+        TaskList taskList = new TaskList();
+        String response = "";
+        try {
+            loadTasks(taskList);
+        } catch (FileNotFoundException e0){
+            response = response + "The file data/duke.txt is not found.";
+            try {
+                createFile();
+            } catch (IOException e1) {
+                response = response + "There has been an error creating a new file. ";
+            }
+            response = response + "A new file data/duke.txt has been created.";
+        } catch (FileFormatException e2) {
+            response = response + "There is a formatting error with the save file.";
+            taskList.clearList();
+        }
+        return new TaskListResponse(taskList, response);
+    }
+
+    private void writeToFile(TaskList taskList) throws IOException {
+        FileWriter fw = new FileWriter("data/duke.txt");
+        for (Task list : taskList.tasks) {
+            fw.write(list.saveTask() + "\n");
+        }
+        fw.close();
+    }
+
+    public String write(TaskList taskList) {
+        try {
+            writeToFile(taskList);
+        } catch (IOException e) {
+            return "There has been an error writing to file.";
+        }
+        return "";
+    }
+}
diff --git a/src/main/java/duke/Ui.java b/src/main/java/duke/Ui.java
new file mode 100644
index 000000000..fdb9b556a
--- /dev/null
+++ b/src/main/java/duke/Ui.java
@@ -0,0 +1,23 @@
+package duke;
+
+public class Ui {
+
+    public static void printMessage(String line) {
+        if (line.isEmpty()) {
+            return;
+        }
+        System.out.println(line);
+    }
+
+    public static void printGreeting() {
+        printMessage("Hello! I'm Duke.");
+    }
+
+    public static void printPrompt() {
+        printMessage("What can I do for you?");
+    }
+
+    public static void printExit() {
+        printMessage("Bye. Hope to see you again soon!");
+    }
+}
diff --git a/src/main/java/duke/commands/AddCommand.java b/src/main/java/duke/commands/AddCommand.java
new file mode 100644
index 000000000..d413e805b
--- /dev/null
+++ b/src/main/java/duke/commands/AddCommand.java
@@ -0,0 +1,29 @@
+package duke.commands;
+
+import duke.tasks.TaskList;
+import duke.tasks.TaskType;
+
+public class AddCommand extends Command {
+
+    public TaskType type;
+
+    public AddCommand(TaskList taskList, String userCommand, TaskType type) {
+        super(taskList, userCommand);
+        this.type = type;
+    }
+
+    @Override
+    public CommandOutput execute() throws Exception {
+        String response = "";
+
+        if (type == TaskType.TODO) {
+            response = taskList.addTodo(userCommand);
+        } else if (type == TaskType.DEADLINE) {
+            response = taskList.addDeadline(userCommand);
+        } else if (type == TaskType.EVENT){
+            response = taskList.addEvent(userCommand);
+        }
+
+        return new CommandOutput(response, true, taskList);
+    }
+}
diff --git a/src/main/java/duke/commands/Command.java b/src/main/java/duke/commands/Command.java
new file mode 100644
index 000000000..70fbb6a86
--- /dev/null
+++ b/src/main/java/duke/commands/Command.java
@@ -0,0 +1,15 @@
+package duke.commands;
+
+import duke.tasks.TaskList;
+
+public abstract class Command {
+    protected TaskList taskList;
+    protected String userCommand;
+
+    protected Command(TaskList taskList, String userCommand) {
+        this.taskList = taskList;
+        this.userCommand = userCommand;
+    }
+
+    public abstract  CommandOutput execute() throws Exception;
+}
diff --git a/src/main/java/duke/commands/CommandOutput.java b/src/main/java/duke/commands/CommandOutput.java
new file mode 100644
index 000000000..1c29bbe99
--- /dev/null
+++ b/src/main/java/duke/commands/CommandOutput.java
@@ -0,0 +1,33 @@
+package duke.commands;
+
+import duke.tasks.TaskList;
+
+public class CommandOutput {
+    private String response;
+    private boolean updated;
+    private TaskList taskList;
+
+    public CommandOutput(String response, boolean updated) {
+        this.response = response;
+        this.updated = updated;
+        taskList = null;
+    }
+
+    public CommandOutput(String response, boolean updated, TaskList taskList) {
+        this.response = response;
+        this.updated = updated;
+        this.taskList = taskList;
+    }
+
+    public String getResponse() {
+        return  response;
+    }
+
+    public boolean isUpdated() {
+        return updated;
+    }
+
+    public TaskList getTaskList() {
+        return taskList;
+    }
+}
diff --git a/src/main/java/duke/commands/DeleteCommand.java b/src/main/java/duke/commands/DeleteCommand.java
new file mode 100644
index 000000000..424a81b64
--- /dev/null
+++ b/src/main/java/duke/commands/DeleteCommand.java
@@ -0,0 +1,15 @@
+package duke.commands;
+
+import duke.tasks.TaskList;
+
+public class DeleteCommand extends Command {
+    public DeleteCommand(TaskList taskList, String userCommand) {
+        super(taskList, userCommand);
+    }
+
+    @Override
+    public CommandOutput execute() throws Exception {
+        String response = taskList.deleteTask(userCommand);
+        return new CommandOutput(response, true, taskList);
+    }
+}
diff --git a/src/main/java/duke/commands/DoneCommand.java b/src/main/java/duke/commands/DoneCommand.java
new file mode 100644
index 000000000..c55a37320
--- /dev/null
+++ b/src/main/java/duke/commands/DoneCommand.java
@@ -0,0 +1,15 @@
+package duke.commands;
+
+import duke.tasks.TaskList;
+
+public class DoneCommand extends Command {
+    public DoneCommand(TaskList taskList, String userCommand) {
+        super(taskList, userCommand);
+    }
+
+    @Override
+    public CommandOutput execute() throws Exception {
+        String response = taskList.taskDone(userCommand);
+        return new CommandOutput(response, true, taskList);
+    }
+}
diff --git a/src/main/java/duke/commands/ListCommand.java b/src/main/java/duke/commands/ListCommand.java
new file mode 100644
index 000000000..e6c64e6fb
--- /dev/null
+++ b/src/main/java/duke/commands/ListCommand.java
@@ -0,0 +1,15 @@
+package duke.commands;
+
+import duke.tasks.TaskList;
+
+public class ListCommand extends Command {
+    public ListCommand(TaskList taskList) {
+        super(taskList, "");
+    }
+
+    @Override
+    public CommandOutput execute() throws Exception {
+        String response = taskList.printList();
+        return new CommandOutput(response, false, taskList);
+    }
+}
diff --git a/src/main/java/duke/commands/NoCommand.java b/src/main/java/duke/commands/NoCommand.java
new file mode 100644
index 000000000..ca31ca4fa
--- /dev/null
+++ b/src/main/java/duke/commands/NoCommand.java
@@ -0,0 +1,15 @@
+package duke.commands;
+
+import duke.tasks.TaskList;
+
+public class NoCommand extends Command {
+    public NoCommand(TaskList taskList) {
+        super(taskList, "");
+    }
+
+    @Override
+    public CommandOutput execute() throws Exception {
+        taskList.noResponse();
+        return new CommandOutput("", false, taskList);
+    }
+}
diff --git a/src/main/java/duke/exceptions/AlreadyDoneException.java b/src/main/java/duke/exceptions/AlreadyDoneException.java
new file mode 100644
index 000000000..d88c37d9e
--- /dev/null
+++ b/src/main/java/duke/exceptions/AlreadyDoneException.java
@@ -0,0 +1,10 @@
+package duke.exceptions;
+
+public class AlreadyDoneException extends Exception {
+    public final String DONE_RESPONSE = "This task is already completed.";
+
+    @Override
+    public String getMessage(){
+        return DONE_RESPONSE;
+    }
+}
diff --git a/src/main/java/duke/exceptions/DeadlineException.java b/src/main/java/duke/exceptions/DeadlineException.java
index bee2449a1..4912c46bb 100644
--- a/src/main/java/duke/exceptions/DeadlineException.java
+++ b/src/main/java/duke/exceptions/DeadlineException.java
@@ -1,4 +1,10 @@
 package duke.exceptions;
 
 public class DeadlineException extends Exception {
+    public final String DEADLINE_RESPONSE = "The description of deadline cannot be empty.";
+
+    @Override
+    public String getMessage() {
+        return DEADLINE_RESPONSE;
+    }
 }
diff --git a/src/main/java/duke/exceptions/DeleteException.java b/src/main/java/duke/exceptions/DeleteException.java
deleted file mode 100644
index f03a5e128..000000000
--- a/src/main/java/duke/exceptions/DeleteException.java
+++ /dev/null
@@ -1,4 +0,0 @@
-package duke.exceptions;
-
-public class DeleteException extends Exception {
-}
diff --git a/src/main/java/duke/exceptions/DeleteFormatException.java b/src/main/java/duke/exceptions/DeleteFormatException.java
new file mode 100644
index 000000000..afdd15bca
--- /dev/null
+++ b/src/main/java/duke/exceptions/DeleteFormatException.java
@@ -0,0 +1,10 @@
+package duke.exceptions;
+
+public class DeleteFormatException extends Exception {
+    public final String DELETE_FORMAT_RESPONSE =  "The description of delete cannot be empty.";
+
+    @Override
+    public String getMessage(){
+        return DELETE_FORMAT_RESPONSE;
+    }
+}
diff --git a/src/main/java/duke/exceptions/DeleteRangeException.java b/src/main/java/duke/exceptions/DeleteRangeException.java
index 09eab86a7..3aa75610b 100644
--- a/src/main/java/duke/exceptions/DeleteRangeException.java
+++ b/src/main/java/duke/exceptions/DeleteRangeException.java
@@ -1,4 +1,10 @@
 package duke.exceptions;
 
 public class DeleteRangeException extends Exception {
+    public final String DELETE_RANGE_RESPONSE =  "That task does not exist.";
+
+    @Override
+    public String getMessage(){
+        return DELETE_RANGE_RESPONSE;
+    }
 }
diff --git a/src/main/java/duke/exceptions/DoneException.java b/src/main/java/duke/exceptions/DoneException.java
deleted file mode 100644
index c5f747d57..000000000
--- a/src/main/java/duke/exceptions/DoneException.java
+++ /dev/null
@@ -1,4 +0,0 @@
-package duke.exceptions;
-
-public class DoneException extends Exception {
-}
diff --git a/src/main/java/duke/exceptions/DoneFormatException.java b/src/main/java/duke/exceptions/DoneFormatException.java
new file mode 100644
index 000000000..ef382d44e
--- /dev/null
+++ b/src/main/java/duke/exceptions/DoneFormatException.java
@@ -0,0 +1,10 @@
+package duke.exceptions;
+
+public class DoneFormatException extends Exception {
+    public final String DONE_FORMAT_RESPONSE =  "The description of done cannot be empty.";
+
+    @Override
+    public String getMessage(){
+        return DONE_FORMAT_RESPONSE;
+    }
+}
diff --git a/src/main/java/duke/exceptions/DoneRangeException.java b/src/main/java/duke/exceptions/DoneRangeException.java
index 1c9f4b5a1..6d8627db3 100644
--- a/src/main/java/duke/exceptions/DoneRangeException.java
+++ b/src/main/java/duke/exceptions/DoneRangeException.java
@@ -1,4 +1,10 @@
 package duke.exceptions;
 
 public class DoneRangeException extends Exception {
+    public final String DONE_RANGE_RESPONSE =  "That task does not exist.";
+
+    @Override
+    public String getMessage(){
+        return DONE_RANGE_RESPONSE;
+    }
 }
diff --git a/src/main/java/duke/exceptions/EmptyException.java b/src/main/java/duke/exceptions/EmptyException.java
new file mode 100644
index 000000000..459054af9
--- /dev/null
+++ b/src/main/java/duke/exceptions/EmptyException.java
@@ -0,0 +1,10 @@
+package duke.exceptions;
+
+public class EmptyException extends Exception {
+    public final String EMPTY_RESPONSE = "Command is empty.";
+
+    @Override
+    public String getMessage(){
+        return EMPTY_RESPONSE;
+    }
+}
diff --git a/src/main/java/duke/exceptions/EmptyListException.java b/src/main/java/duke/exceptions/EmptyListException.java
index f9e6a4248..a72c34663 100644
--- a/src/main/java/duke/exceptions/EmptyListException.java
+++ b/src/main/java/duke/exceptions/EmptyListException.java
@@ -1,4 +1,10 @@
 package duke.exceptions;
 
 public class EmptyListException extends Exception {
+    public final String EMPTY_LIST_RESPONSE = "The list is empty.";
+
+    @Override
+    public String getMessage(){
+        return EMPTY_LIST_RESPONSE;
+    }
 }
diff --git a/src/main/java/duke/exceptions/EventException.java b/src/main/java/duke/exceptions/EventException.java
index 7dde535d8..d064169ad 100644
--- a/src/main/java/duke/exceptions/EventException.java
+++ b/src/main/java/duke/exceptions/EventException.java
@@ -1,4 +1,10 @@
 package duke.exceptions;
 
 public class EventException extends Exception {
+    public final String EVENT_RESPONSE = "The description of event cannot be empty.";
+
+    @Override
+    public String getMessage(){
+        return EVENT_RESPONSE;
+    }
 }
diff --git a/src/main/java/duke/exceptions/FileFormatException.java b/src/main/java/duke/exceptions/FileFormatException.java
new file mode 100644
index 000000000..4eaf6d9af
--- /dev/null
+++ b/src/main/java/duke/exceptions/FileFormatException.java
@@ -0,0 +1,4 @@
+package duke.exceptions;
+
+public class FileFormatException extends Exception {
+}
diff --git a/src/main/java/duke/exceptions/TodoException.java b/src/main/java/duke/exceptions/TodoException.java
index 0ab691e07..9fcc93f53 100644
--- a/src/main/java/duke/exceptions/TodoException.java
+++ b/src/main/java/duke/exceptions/TodoException.java
@@ -1,4 +1,10 @@
 package duke.exceptions;
 
 public class TodoException extends Exception {
+    public final String TODO_RESPONSE = "The description of todo cannot be empty.";
+
+    @Override
+    public String getMessage(){
+        return TODO_RESPONSE;
+    }
 }
diff --git a/src/main/java/duke/tasks/Deadline.java b/src/main/java/duke/tasks/Deadline.java
index 4ce536a06..6de943f67 100644
--- a/src/main/java/duke/tasks/Deadline.java
+++ b/src/main/java/duke/tasks/Deadline.java
@@ -1,6 +1,7 @@
 package duke.tasks;
 
-public class Deadline extends Todo {
+public class Deadline extends Task {
+    private TaskType type = TaskType.DEADLINE;
     protected String by;
 
     public Deadline(String description, String by) {
@@ -20,9 +21,9 @@ public void setBy(String by) {
         this.by = by;
     }
 
-    public void printTask() {
-        System.out.print("[D][" + getStatusIcon() + "] " + getDescription());
-        System.out.println("(by:" + by + ")");
+    @Override
+    public String printTask() {
+        return "[D][" + getStatusIcon() + "] " + getDescription() + " (by:" + by + ")";
     }
 
     @Override
diff --git a/src/main/java/duke/tasks/Event.java b/src/main/java/duke/tasks/Event.java
index c92dc384d..314245efc 100644
--- a/src/main/java/duke/tasks/Event.java
+++ b/src/main/java/duke/tasks/Event.java
@@ -1,6 +1,7 @@
 package duke.tasks;
 
-public class Event extends Todo{
+public class Event extends Task {
+    private TaskType type = TaskType.EVENT;
     protected String at;
 
     public Event(String description, String at) {
@@ -19,9 +20,9 @@ public void setAt(String at) {
         this.at = at;
     }
 
-    public void printTask() {
-        System.out.print("[E][" + getStatusIcon() + "] " + getDescription());
-        System.out.println("(at:" + at + ")");
+    @Override
+    public String printTask() {
+        return "[E][" + getStatusIcon() + "] " + getDescription() + "(at:" + at + ")";
     }
 
     @Override
diff --git a/src/main/java/duke/tasks/Task.java b/src/main/java/duke/tasks/Task.java
index 4a11cf0e9..069167535 100644
--- a/src/main/java/duke/tasks/Task.java
+++ b/src/main/java/duke/tasks/Task.java
@@ -23,12 +23,16 @@ public String getDescription() {
         return description;
     }
 
+    public boolean isDone() {
+        return isDone;
+    }
+
     public void setDone() {
         isDone = true;
     }
 
-    public void printTask() {
-        System.out.println(description);
+    public String printTask() {
+        return "";
     }
 
     public String saveTask() {
diff --git a/src/main/java/duke/tasks/TaskList.java b/src/main/java/duke/tasks/TaskList.java
new file mode 100644
index 000000000..cbc728175
--- /dev/null
+++ b/src/main/java/duke/tasks/TaskList.java
@@ -0,0 +1,107 @@
+package duke.tasks;
+
+import duke.exceptions.*;
+
+import java.util.ArrayList;
+
+public class TaskList {
+    public ArrayList<Task> tasks = new ArrayList<>();
+
+    public String ADDED = "Got it. I've added this task:";
+    public String REMOVED = "Noted. I've removed this task:";
+    public String ACKNOWLEDGED = "Nice! I've marked this task as done:";
+    public String LIST_START = "Here are the tasks in your list:";
+
+    public String TaskListResponse(String line, int index){
+        return line + "\n" + tasks.get(index).getDescription();
+    }
+
+    public void noResponse () throws EmptyException {
+        throw new EmptyException();
+    }
+
+    public String printTaskCount() {
+        return "Now you have " + tasks.size() + " tasks in the list.";
+    }
+
+    public String printList() throws EmptyListException {
+        if (tasks.size() == 0) {
+            throw new EmptyListException();
+        }
+        String listResponse = LIST_START;
+        for (int i = 1; i <= tasks.size(); i += 1) {
+            listResponse = listResponse + "\n" +  i + ". " + tasks.get(i - 1).printTask();
+        }
+        return listResponse;
+    }
+
+    public TaskList() {
+    }
+
+    public String taskDone(String line)
+            throws DoneFormatException, AlreadyDoneException, DoneRangeException {
+        if (!line.matches("\\d+")) {
+            throw new DoneFormatException();
+        }
+        int index = Integer.parseInt(line) - 1;
+        if (index >= tasks.size()) {
+            throw new DoneRangeException();
+        } else if (tasks.get(index).isDone()) {
+            throw new AlreadyDoneException();
+        } else {
+            tasks.get(index).setDone();
+            return TaskListResponse(ACKNOWLEDGED, index);
+        }
+    }
+
+    public String addTodo(String line) throws TodoException {
+        if (line.equals("") || line.equals("todo")) {
+            throw new TodoException();
+        } else {
+            tasks.add(new Todo(line));
+            return TaskListResponse(ADDED, tasks.size()-1) +"\n" + printTaskCount();
+        }
+    }
+
+    public String addDeadline(String line) throws DeadlineException {
+        if (!line.matches("(.*)/by(.*)")) {
+            throw new DeadlineException();
+        } else {
+            //extracting the description and date
+            String description = line.replaceAll("/.+", "");
+            String by = line.replaceAll(".+/by", "");
+            tasks.add(new Deadline(description, by));
+            return TaskListResponse(ADDED, tasks.size()-1) +"\n" + printTaskCount();
+        }
+    }
+
+    public String addEvent(String line) throws EventException {
+        if (!line.matches("(.*)/at(.*)")) {
+            throw new EventException();
+        } else {
+            //extracting the description and date
+            String description = line.replaceAll("/.+", "");
+            String at = line.replaceAll(".+/at", "");
+            tasks.add(new Event(description, at));
+            return TaskListResponse(ADDED, tasks.size()-1) +"\n" + printTaskCount();
+        }
+    }
+
+    public String deleteTask(String line) throws DeleteFormatException, DeleteRangeException {
+        if (!line.matches("\\d+")) {
+            throw new DeleteFormatException();
+        }
+        int index = Integer.parseInt(line) - 1;
+        if (index >= tasks.size()) {
+            throw new DeleteRangeException();
+        } else {
+            String response = TaskListResponse(REMOVED, index);
+            tasks.remove(index);
+            return response +"\n" + printTaskCount();
+        }
+    }
+
+    public void clearList(){
+        tasks.clear();
+    }
+}
diff --git a/src/main/java/duke/tasks/TaskListResponse.java b/src/main/java/duke/tasks/TaskListResponse.java
new file mode 100644
index 000000000..b49e46785
--- /dev/null
+++ b/src/main/java/duke/tasks/TaskListResponse.java
@@ -0,0 +1,13 @@
+package duke.tasks;
+
+import duke.tasks.TaskList;
+
+public class TaskListResponse {
+    public TaskList taskList;
+    public String response;
+
+    public TaskListResponse(TaskList taskList, String response) {
+        this.taskList = taskList;
+        this.response = response;
+    }
+}
diff --git a/src/main/java/duke/tasks/TaskType.java b/src/main/java/duke/tasks/TaskType.java
new file mode 100644
index 000000000..e641c880a
--- /dev/null
+++ b/src/main/java/duke/tasks/TaskType.java
@@ -0,0 +1,5 @@
+package duke.tasks;
+
+public enum TaskType {
+    TODO, EVENT, DEADLINE
+}
diff --git a/src/main/java/duke/tasks/Todo.java b/src/main/java/duke/tasks/Todo.java
index b47b86345..30f8c2c3c 100644
--- a/src/main/java/duke/tasks/Todo.java
+++ b/src/main/java/duke/tasks/Todo.java
@@ -1,6 +1,7 @@
 package duke.tasks;
 
 public class Todo extends Task{
+    private TaskType type = TaskType.TODO;
 
     public Todo(String description) {
         super(description);
@@ -9,8 +10,9 @@ public Todo(String description, boolean isDone) {
         super(description, isDone);
     }
 
-    public void printTask() {
-        System.out.println("[T][" + getStatusIcon() + "] " + getDescription());
+    @Override
+    public String printTask() {
+        return "[T][" + getStatusIcon() + "] " + getDescription();
     }
 
     @Override
diff --git a/text-ui-test/EXPECTED.TXT b/text-ui-test/EXPECTED.TXT
index 0cdc00662..791744bdc 100644
--- a/text-ui-test/EXPECTED.TXT
+++ b/text-ui-test/EXPECTED.TXT
@@ -1,20 +1,32 @@
-Hello! I'm Duke
+The file data/duke.txt is not found.A new file data/duke.txt has been created.
+Hello! I'm Duke.
+What can I do for you?
+Command is empty.
 What can I do for you?
-Could you say that again?
 Got it. I've added this task:
-[T][ ] eat cake
+eat cake
 Now you have 1 tasks in the list.
+What can I do for you?
 Got it. I've added this task:
-[D][ ] eat chocolate cake (by: Friday 2pm)
+eat chocolate cake
 Now you have 2 tasks in the list.
+What can I do for you?
 Got it. I've added this task:
-[E][ ] attend cake buffet (at: Saturday 5pm)
+attend cake buffet
 Now you have 3 tasks in the list.
+What can I do for you?
 Nice! I've marked this task as done:
-[T][X] eat cake
+eat cake
+What can I do for you?
+The description of done cannot be empty.
+What can I do for you?
 The description of todo cannot be empty.
+What can I do for you?
 Here are the tasks in your list:
-1.[T][X] eat cake
-2.[D][ ] eat chocolate cake (by: Friday 2pm)
-3.[E][ ] attend cake buffet (at: Saturday 5pm)
-Could you say that again?
+1. [T][X] eat cake
+2. [D][ ] eat chocolate cake  (by: Friday 2pm)
+3. [E][ ] attend cake buffet (at: Saturday 5pm)
+What can I do for you?
+Command is empty.
+What can I do for you?
+Bye. Hope to see you again soon!
diff --git a/text-ui-test/input.txt b/text-ui-test/input.txt
index bec17eb26..375c6cf2c 100644
--- a/text-ui-test/input.txt
+++ b/text-ui-test/input.txt
@@ -3,6 +3,7 @@ todo eat cake
 deadline eat chocolate cake /by Friday 2pm
 event attend cake buffet /at Saturday 5pm
 done 1
+done a
 todo
 list
 cake

From e39676bfab450f631a631b4bd0b93ca19501821b Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Mon, 27 Sep 2021 11:02:48 +0800
Subject: [PATCH 22/25] Level-9

---
 data/duke.txt                                 |  0
 src/main/java/duke/Parser.java                |  4 ++++
 src/main/java/duke/commands/FindCommand.java  | 16 ++++++++++++++++
 src/main/java/duke/commands/ListCommand.java  |  2 +-
 .../duke/exceptions/NotFoundException.java    | 10 ++++++++++
 src/main/java/duke/tasks/TaskList.java        | 19 +++++++++++++++++++
 6 files changed, 50 insertions(+), 1 deletion(-)
 delete mode 100644 data/duke.txt
 create mode 100644 src/main/java/duke/commands/FindCommand.java
 create mode 100644 src/main/java/duke/exceptions/NotFoundException.java

diff --git a/data/duke.txt b/data/duke.txt
deleted file mode 100644
index e69de29bb..000000000
diff --git a/src/main/java/duke/Parser.java b/src/main/java/duke/Parser.java
index ebad1c37f..afbd87e51 100644
--- a/src/main/java/duke/Parser.java
+++ b/src/main/java/duke/Parser.java
@@ -3,6 +3,7 @@
 import duke.commands.Command;
 import duke.commands.ListCommand;
 import duke.commands.AddCommand;
+import duke.commands.FindCommand;
 import duke.commands.NoCommand;
 import duke.commands.DoneCommand;
 import duke.commands.DeleteCommand;
@@ -15,6 +16,7 @@ public class Parser {
     public final String TODO = "todo";
     public final String DEADLINE = "deadline";
     public final String EVENT = "event";
+    public final String FIND = "find";
     public final String DONE = "done";
     public final String DELETE = "delete";
     public final String BYE = "bye";
@@ -31,6 +33,8 @@ public Command parseCommand(TaskList taskList, String line) {
             return new AddCommand(taskList, userCommand, TaskType.DEADLINE);
         } else if (command.equals(EVENT)) {
             return new AddCommand(taskList, userCommand, TaskType.EVENT);
+        } else if (command.equals(FIND)) {
+            return new FindCommand(taskList, userCommand);
         } else if (command.equals(DONE)) {
             return new DoneCommand(taskList, userCommand);
         } else if (command.equals(DELETE)) {
diff --git a/src/main/java/duke/commands/FindCommand.java b/src/main/java/duke/commands/FindCommand.java
new file mode 100644
index 000000000..f2347ec8b
--- /dev/null
+++ b/src/main/java/duke/commands/FindCommand.java
@@ -0,0 +1,16 @@
+package duke.commands;
+
+import duke.tasks.TaskList;
+
+public class FindCommand extends Command {
+    public FindCommand(TaskList taskList, String userCommand){
+        super(taskList, userCommand);
+    }
+
+    @Override
+    public CommandOutput execute() throws Exception{
+        String response = taskList.findTask(userCommand);
+
+        return new CommandOutput(response, false);
+    }
+}
diff --git a/src/main/java/duke/commands/ListCommand.java b/src/main/java/duke/commands/ListCommand.java
index e6c64e6fb..4556e8138 100644
--- a/src/main/java/duke/commands/ListCommand.java
+++ b/src/main/java/duke/commands/ListCommand.java
@@ -10,6 +10,6 @@ public ListCommand(TaskList taskList) {
     @Override
     public CommandOutput execute() throws Exception {
         String response = taskList.printList();
-        return new CommandOutput(response, false, taskList);
+        return new CommandOutput(response, false);
     }
 }
diff --git a/src/main/java/duke/exceptions/NotFoundException.java b/src/main/java/duke/exceptions/NotFoundException.java
new file mode 100644
index 000000000..9fff3744f
--- /dev/null
+++ b/src/main/java/duke/exceptions/NotFoundException.java
@@ -0,0 +1,10 @@
+package duke.exceptions;
+
+public class NotFoundException extends Exception {
+    public final String NOT_FOUND_RESPONSE = "There are no matching tasks.";
+
+    @Override
+    public String getMessage(){
+        return NOT_FOUND_RESPONSE;
+    }
+}
diff --git a/src/main/java/duke/tasks/TaskList.java b/src/main/java/duke/tasks/TaskList.java
index cbc728175..fd70c1dda 100644
--- a/src/main/java/duke/tasks/TaskList.java
+++ b/src/main/java/duke/tasks/TaskList.java
@@ -11,6 +11,7 @@ public class TaskList {
     public String REMOVED = "Noted. I've removed this task:";
     public String ACKNOWLEDGED = "Nice! I've marked this task as done:";
     public String LIST_START = "Here are the tasks in your list:";
+    public String FIND_START = "Here are the matching tasks in your list:";
 
     public String TaskListResponse(String line, int index){
         return line + "\n" + tasks.get(index).getDescription();
@@ -101,6 +102,24 @@ public String deleteTask(String line) throws DeleteFormatException, DeleteRangeE
         }
     }
 
+    public String findTask(String line) throws NotFoundException {
+        String foundList = FIND_START;
+
+        int tasksFound = 0;
+
+        for (int i = 1; i <= tasks.size(); ++i) {
+            if (tasks.get(i - 1).getDescription().toLowerCase().contains(line.toLowerCase())) {
+                tasksFound += 1;
+                foundList = foundList + "\n" + i + ". " + tasks.get(i - 1).printTask();
+            }
+        }
+
+        if (tasksFound == 0){
+            throw new NotFoundException();
+        }
+        return foundList;
+    }
+
     public void clearList(){
         tasks.clear();
     }

From 76199bd713985a491b297afe999bc0d0b73966c5 Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Mon, 27 Sep 2021 11:46:45 +0800
Subject: [PATCH 23/25] A-JavaDoc

---
 src/main/java/duke/Duke.java                          |  2 ++
 src/main/java/duke/Parser.java                        |  1 +
 src/main/java/duke/Storage.java                       |  5 +++++
 src/main/java/duke/Ui.java                            |  1 +
 src/main/java/duke/commands/Command.java              |  2 ++
 src/main/java/duke/commands/CommandOutput.java        |  1 +
 src/main/java/duke/commands/DeleteCommand.java        |  1 +
 src/main/java/duke/commands/DoneCommand.java          |  1 +
 src/main/java/duke/commands/FindCommand.java          |  1 +
 src/main/java/duke/commands/ListCommand.java          |  1 +
 src/main/java/duke/commands/NoCommand.java            |  1 +
 .../java/duke/exceptions/AlreadyDoneException.java    |  2 ++
 src/main/java/duke/exceptions/DeadlineException.java  |  4 +++-
 .../java/duke/exceptions/DeleteFormatException.java   |  4 +++-
 .../java/duke/exceptions/DeleteRangeException.java    |  2 ++
 .../java/duke/exceptions/DoneFormatException.java     |  4 +++-
 src/main/java/duke/exceptions/DoneRangeException.java |  2 ++
 src/main/java/duke/exceptions/EmptyException.java     |  2 ++
 src/main/java/duke/exceptions/EmptyListException.java |  2 ++
 src/main/java/duke/exceptions/EventException.java     |  4 +++-
 .../java/duke/exceptions/FileFormatException.java     |  1 +
 src/main/java/duke/exceptions/NotFoundException.java  |  2 ++
 src/main/java/duke/exceptions/TodoException.java      |  4 +++-
 src/main/java/duke/tasks/Deadline.java                |  1 +
 src/main/java/duke/tasks/Event.java                   |  1 +
 src/main/java/duke/tasks/Task.java                    |  1 +
 src/main/java/duke/tasks/TaskList.java                | 11 +++++++++--
 src/main/java/duke/tasks/TaskListResponse.java        |  3 +--
 src/main/java/duke/tasks/Todo.java                    |  1 +
 text-ui-test/EXPECTED.TXT                             |  8 +++-----
 text-ui-test/input.txt                                |  4 +---
 31 files changed, 63 insertions(+), 17 deletions(-)

diff --git a/src/main/java/duke/Duke.java b/src/main/java/duke/Duke.java
index 1df3de12b..e0704183c 100644
--- a/src/main/java/duke/Duke.java
+++ b/src/main/java/duke/Duke.java
@@ -22,6 +22,7 @@ public Duke(String filePath) {
         Ui.printMessage(response.response);
     }
 
+    //attempts to execute the user command
     public CommandOutput executeCommand(Command command) {
         try {
                 return command.execute();
@@ -30,6 +31,7 @@ public CommandOutput executeCommand(Command command) {
         }
     }
 
+    //runs the program
     public void run() {
         ui.printGreeting();
         String line;
diff --git a/src/main/java/duke/Parser.java b/src/main/java/duke/Parser.java
index afbd87e51..c9faa8efe 100644
--- a/src/main/java/duke/Parser.java
+++ b/src/main/java/duke/Parser.java
@@ -21,6 +21,7 @@ public class Parser {
     public final String DELETE = "delete";
     public final String BYE = "bye";
 
+    //executes program according to user command
     public Command parseCommand(TaskList taskList, String line) {
         final String[] splitLine = line.split(" ", 2);
         final String command = splitLine[0];
diff --git a/src/main/java/duke/Storage.java b/src/main/java/duke/Storage.java
index 3fc7da82a..9ba5b3ee6 100644
--- a/src/main/java/duke/Storage.java
+++ b/src/main/java/duke/Storage.java
@@ -27,6 +27,7 @@ public Storage(String filePath) {
         this.f = new File(filePath);
     }
 
+    //load tasks from save file if save file exists
     public void loadTasks(TaskList taskList) throws FileNotFoundException, FileFormatException {
         Scanner s = new Scanner(f); // create a Scanner using the File as the source
         while (s.hasNext()) {
@@ -50,12 +51,14 @@ public void loadTasks(TaskList taskList) throws FileNotFoundException, FileForma
         }
     }
 
+    //creates a save file
     public void createFile() throws IOException {
         Path pathToFile = Paths.get("data/duke.txt");
         Files.createDirectories(pathToFile.getParent());
         f.createNewFile();
     }
 
+    //program output for save file
     public TaskListResponse initialiseTasks() {
         TaskList taskList = new TaskList();
         String response = "";
@@ -76,6 +79,7 @@ public TaskListResponse initialiseTasks() {
         return new TaskListResponse(taskList, response);
     }
 
+    //writing to save file
     private void writeToFile(TaskList taskList) throws IOException {
         FileWriter fw = new FileWriter("data/duke.txt");
         for (Task list : taskList.tasks) {
@@ -84,6 +88,7 @@ private void writeToFile(TaskList taskList) throws IOException {
         fw.close();
     }
 
+    //program output for writing to save file
     public String write(TaskList taskList) {
         try {
             writeToFile(taskList);
diff --git a/src/main/java/duke/Ui.java b/src/main/java/duke/Ui.java
index fdb9b556a..46bab224b 100644
--- a/src/main/java/duke/Ui.java
+++ b/src/main/java/duke/Ui.java
@@ -2,6 +2,7 @@
 
 public class Ui {
 
+    //prints program output
     public static void printMessage(String line) {
         if (line.isEmpty()) {
             return;
diff --git a/src/main/java/duke/commands/Command.java b/src/main/java/duke/commands/Command.java
index 70fbb6a86..f9b109ab2 100644
--- a/src/main/java/duke/commands/Command.java
+++ b/src/main/java/duke/commands/Command.java
@@ -3,6 +3,7 @@
 import duke.tasks.TaskList;
 
 public abstract class Command {
+
     protected TaskList taskList;
     protected String userCommand;
 
@@ -11,5 +12,6 @@ protected Command(TaskList taskList, String userCommand) {
         this.userCommand = userCommand;
     }
 
+    //attempts to execute program according to user command
     public abstract  CommandOutput execute() throws Exception;
 }
diff --git a/src/main/java/duke/commands/CommandOutput.java b/src/main/java/duke/commands/CommandOutput.java
index 1c29bbe99..fa2463fb9 100644
--- a/src/main/java/duke/commands/CommandOutput.java
+++ b/src/main/java/duke/commands/CommandOutput.java
@@ -3,6 +3,7 @@
 import duke.tasks.TaskList;
 
 public class CommandOutput {
+
     private String response;
     private boolean updated;
     private TaskList taskList;
diff --git a/src/main/java/duke/commands/DeleteCommand.java b/src/main/java/duke/commands/DeleteCommand.java
index 424a81b64..c6ddb5a7b 100644
--- a/src/main/java/duke/commands/DeleteCommand.java
+++ b/src/main/java/duke/commands/DeleteCommand.java
@@ -3,6 +3,7 @@
 import duke.tasks.TaskList;
 
 public class DeleteCommand extends Command {
+
     public DeleteCommand(TaskList taskList, String userCommand) {
         super(taskList, userCommand);
     }
diff --git a/src/main/java/duke/commands/DoneCommand.java b/src/main/java/duke/commands/DoneCommand.java
index c55a37320..838112870 100644
--- a/src/main/java/duke/commands/DoneCommand.java
+++ b/src/main/java/duke/commands/DoneCommand.java
@@ -3,6 +3,7 @@
 import duke.tasks.TaskList;
 
 public class DoneCommand extends Command {
+
     public DoneCommand(TaskList taskList, String userCommand) {
         super(taskList, userCommand);
     }
diff --git a/src/main/java/duke/commands/FindCommand.java b/src/main/java/duke/commands/FindCommand.java
index f2347ec8b..1a3219345 100644
--- a/src/main/java/duke/commands/FindCommand.java
+++ b/src/main/java/duke/commands/FindCommand.java
@@ -3,6 +3,7 @@
 import duke.tasks.TaskList;
 
 public class FindCommand extends Command {
+
     public FindCommand(TaskList taskList, String userCommand){
         super(taskList, userCommand);
     }
diff --git a/src/main/java/duke/commands/ListCommand.java b/src/main/java/duke/commands/ListCommand.java
index 4556e8138..b361140f6 100644
--- a/src/main/java/duke/commands/ListCommand.java
+++ b/src/main/java/duke/commands/ListCommand.java
@@ -3,6 +3,7 @@
 import duke.tasks.TaskList;
 
 public class ListCommand extends Command {
+
     public ListCommand(TaskList taskList) {
         super(taskList, "");
     }
diff --git a/src/main/java/duke/commands/NoCommand.java b/src/main/java/duke/commands/NoCommand.java
index ca31ca4fa..a18a38831 100644
--- a/src/main/java/duke/commands/NoCommand.java
+++ b/src/main/java/duke/commands/NoCommand.java
@@ -3,6 +3,7 @@
 import duke.tasks.TaskList;
 
 public class NoCommand extends Command {
+
     public NoCommand(TaskList taskList) {
         super(taskList, "");
     }
diff --git a/src/main/java/duke/exceptions/AlreadyDoneException.java b/src/main/java/duke/exceptions/AlreadyDoneException.java
index d88c37d9e..e3b0caa02 100644
--- a/src/main/java/duke/exceptions/AlreadyDoneException.java
+++ b/src/main/java/duke/exceptions/AlreadyDoneException.java
@@ -1,6 +1,8 @@
 package duke.exceptions;
 
+//used when user tries to complete an already completed task
 public class AlreadyDoneException extends Exception {
+
     public final String DONE_RESPONSE = "This task is already completed.";
 
     @Override
diff --git a/src/main/java/duke/exceptions/DeadlineException.java b/src/main/java/duke/exceptions/DeadlineException.java
index 4912c46bb..c4616055d 100644
--- a/src/main/java/duke/exceptions/DeadlineException.java
+++ b/src/main/java/duke/exceptions/DeadlineException.java
@@ -1,7 +1,9 @@
 package duke.exceptions;
 
+//used when deadline description is in the wrong format
 public class DeadlineException extends Exception {
-    public final String DEADLINE_RESPONSE = "The description of deadline cannot be empty.";
+
+    public final String DEADLINE_RESPONSE = "The following format must be used: deadline [description] /by [date and time]";
 
     @Override
     public String getMessage() {
diff --git a/src/main/java/duke/exceptions/DeleteFormatException.java b/src/main/java/duke/exceptions/DeleteFormatException.java
index afdd15bca..375f11c0d 100644
--- a/src/main/java/duke/exceptions/DeleteFormatException.java
+++ b/src/main/java/duke/exceptions/DeleteFormatException.java
@@ -1,7 +1,9 @@
 package duke.exceptions;
 
+//used when delete description is in the wrong format
 public class DeleteFormatException extends Exception {
-    public final String DELETE_FORMAT_RESPONSE =  "The description of delete cannot be empty.";
+
+    public final String DELETE_FORMAT_RESPONSE =  "The following format must be used: delete [index]";
 
     @Override
     public String getMessage(){
diff --git a/src/main/java/duke/exceptions/DeleteRangeException.java b/src/main/java/duke/exceptions/DeleteRangeException.java
index 3aa75610b..bfac4906a 100644
--- a/src/main/java/duke/exceptions/DeleteRangeException.java
+++ b/src/main/java/duke/exceptions/DeleteRangeException.java
@@ -1,6 +1,8 @@
 package duke.exceptions;
 
+//used when task user wants to delete does not exist
 public class DeleteRangeException extends Exception {
+
     public final String DELETE_RANGE_RESPONSE =  "That task does not exist.";
 
     @Override
diff --git a/src/main/java/duke/exceptions/DoneFormatException.java b/src/main/java/duke/exceptions/DoneFormatException.java
index ef382d44e..ba3e8e370 100644
--- a/src/main/java/duke/exceptions/DoneFormatException.java
+++ b/src/main/java/duke/exceptions/DoneFormatException.java
@@ -1,7 +1,9 @@
 package duke.exceptions;
 
+//used when done description is in the wrong format
 public class DoneFormatException extends Exception {
-    public final String DONE_FORMAT_RESPONSE =  "The description of done cannot be empty.";
+
+    public final String DONE_FORMAT_RESPONSE =  "The following format must be used: done [index]";
 
     @Override
     public String getMessage(){
diff --git a/src/main/java/duke/exceptions/DoneRangeException.java b/src/main/java/duke/exceptions/DoneRangeException.java
index 6d8627db3..fdafaff6f 100644
--- a/src/main/java/duke/exceptions/DoneRangeException.java
+++ b/src/main/java/duke/exceptions/DoneRangeException.java
@@ -1,6 +1,8 @@
 package duke.exceptions;
 
+//used when task user wants to complete does not exist
 public class DoneRangeException extends Exception {
+
     public final String DONE_RANGE_RESPONSE =  "That task does not exist.";
 
     @Override
diff --git a/src/main/java/duke/exceptions/EmptyException.java b/src/main/java/duke/exceptions/EmptyException.java
index 459054af9..8dca54a82 100644
--- a/src/main/java/duke/exceptions/EmptyException.java
+++ b/src/main/java/duke/exceptions/EmptyException.java
@@ -1,6 +1,8 @@
 package duke.exceptions;
 
+//used when user did not input a command
 public class EmptyException extends Exception {
+
     public final String EMPTY_RESPONSE = "Command is empty.";
 
     @Override
diff --git a/src/main/java/duke/exceptions/EmptyListException.java b/src/main/java/duke/exceptions/EmptyListException.java
index a72c34663..af62c5c6d 100644
--- a/src/main/java/duke/exceptions/EmptyListException.java
+++ b/src/main/java/duke/exceptions/EmptyListException.java
@@ -1,6 +1,8 @@
 package duke.exceptions;
 
+//used when user tries the list command even though list is empty
 public class EmptyListException extends Exception {
+
     public final String EMPTY_LIST_RESPONSE = "The list is empty.";
 
     @Override
diff --git a/src/main/java/duke/exceptions/EventException.java b/src/main/java/duke/exceptions/EventException.java
index d064169ad..f2789fad9 100644
--- a/src/main/java/duke/exceptions/EventException.java
+++ b/src/main/java/duke/exceptions/EventException.java
@@ -1,7 +1,9 @@
 package duke.exceptions;
 
+//used when event description is in the wrong format
 public class EventException extends Exception {
-    public final String EVENT_RESPONSE = "The description of event cannot be empty.";
+
+    public final String EVENT_RESPONSE = "The following format must be used: event [description] /at [date and time]";
 
     @Override
     public String getMessage(){
diff --git a/src/main/java/duke/exceptions/FileFormatException.java b/src/main/java/duke/exceptions/FileFormatException.java
index 4eaf6d9af..6396dc754 100644
--- a/src/main/java/duke/exceptions/FileFormatException.java
+++ b/src/main/java/duke/exceptions/FileFormatException.java
@@ -1,4 +1,5 @@
 package duke.exceptions;
 
+//used when save file is in the wrong format
 public class FileFormatException extends Exception {
 }
diff --git a/src/main/java/duke/exceptions/NotFoundException.java b/src/main/java/duke/exceptions/NotFoundException.java
index 9fff3744f..9868dd2af 100644
--- a/src/main/java/duke/exceptions/NotFoundException.java
+++ b/src/main/java/duke/exceptions/NotFoundException.java
@@ -1,6 +1,8 @@
 package duke.exceptions;
 
+//used when no matching tasks are found from the find command
 public class NotFoundException extends Exception {
+
     public final String NOT_FOUND_RESPONSE = "There are no matching tasks.";
 
     @Override
diff --git a/src/main/java/duke/exceptions/TodoException.java b/src/main/java/duke/exceptions/TodoException.java
index 9fcc93f53..49589aa23 100644
--- a/src/main/java/duke/exceptions/TodoException.java
+++ b/src/main/java/duke/exceptions/TodoException.java
@@ -1,7 +1,9 @@
 package duke.exceptions;
 
+//used when todo description is in the wrong format
 public class TodoException extends Exception {
-    public final String TODO_RESPONSE = "The description of todo cannot be empty.";
+
+    public final String TODO_RESPONSE = "The following format must be used: todo [description]";
 
     @Override
     public String getMessage(){
diff --git a/src/main/java/duke/tasks/Deadline.java b/src/main/java/duke/tasks/Deadline.java
index 6de943f67..678c8b03a 100644
--- a/src/main/java/duke/tasks/Deadline.java
+++ b/src/main/java/duke/tasks/Deadline.java
@@ -1,6 +1,7 @@
 package duke.tasks;
 
 public class Deadline extends Task {
+
     private TaskType type = TaskType.DEADLINE;
     protected String by;
 
diff --git a/src/main/java/duke/tasks/Event.java b/src/main/java/duke/tasks/Event.java
index 314245efc..f85cf61bb 100644
--- a/src/main/java/duke/tasks/Event.java
+++ b/src/main/java/duke/tasks/Event.java
@@ -1,6 +1,7 @@
 package duke.tasks;
 
 public class Event extends Task {
+
     private TaskType type = TaskType.EVENT;
     protected String at;
 
diff --git a/src/main/java/duke/tasks/Task.java b/src/main/java/duke/tasks/Task.java
index 069167535..84458bb4a 100644
--- a/src/main/java/duke/tasks/Task.java
+++ b/src/main/java/duke/tasks/Task.java
@@ -1,6 +1,7 @@
 package duke.tasks;
 
 public class Task {
+
     protected String description;
     protected boolean isDone;
 
diff --git a/src/main/java/duke/tasks/TaskList.java b/src/main/java/duke/tasks/TaskList.java
index fd70c1dda..eab67fb1a 100644
--- a/src/main/java/duke/tasks/TaskList.java
+++ b/src/main/java/duke/tasks/TaskList.java
@@ -5,6 +5,7 @@
 import java.util.ArrayList;
 
 public class TaskList {
+
     public ArrayList<Task> tasks = new ArrayList<>();
 
     public String ADDED = "Got it. I've added this task:";
@@ -25,6 +26,7 @@ public String printTaskCount() {
         return "Now you have " + tasks.size() + " tasks in the list.";
     }
 
+    //displays the list to the user
     public String printList() throws EmptyListException {
         if (tasks.size() == 0) {
             throw new EmptyListException();
@@ -39,6 +41,7 @@ public String printList() throws EmptyListException {
     public TaskList() {
     }
 
+    //executes program to mark a task as done
     public String taskDone(String line)
             throws DoneFormatException, AlreadyDoneException, DoneRangeException {
         if (!line.matches("\\d+")) {
@@ -55,6 +58,7 @@ public String taskDone(String line)
         }
     }
 
+    //adds a todo task to the list
     public String addTodo(String line) throws TodoException {
         if (line.equals("") || line.equals("todo")) {
             throw new TodoException();
@@ -64,6 +68,7 @@ public String addTodo(String line) throws TodoException {
         }
     }
 
+    //adds a deadline task to the list
     public String addDeadline(String line) throws DeadlineException {
         if (!line.matches("(.*)/by(.*)")) {
             throw new DeadlineException();
@@ -76,6 +81,7 @@ public String addDeadline(String line) throws DeadlineException {
         }
     }
 
+    //adds an event task to the list
     public String addEvent(String line) throws EventException {
         if (!line.matches("(.*)/at(.*)")) {
             throw new EventException();
@@ -88,6 +94,7 @@ public String addEvent(String line) throws EventException {
         }
     }
 
+    //deletes task from the list
     public String deleteTask(String line) throws DeleteFormatException, DeleteRangeException {
         if (!line.matches("\\d+")) {
             throw new DeleteFormatException();
@@ -102,11 +109,10 @@ public String deleteTask(String line) throws DeleteFormatException, DeleteRangeE
         }
     }
 
+    //finds matching tasks in the list
     public String findTask(String line) throws NotFoundException {
         String foundList = FIND_START;
-
         int tasksFound = 0;
-
         for (int i = 1; i <= tasks.size(); ++i) {
             if (tasks.get(i - 1).getDescription().toLowerCase().contains(line.toLowerCase())) {
                 tasksFound += 1;
@@ -120,6 +126,7 @@ public String findTask(String line) throws NotFoundException {
         return foundList;
     }
 
+    //clears existing list
     public void clearList(){
         tasks.clear();
     }
diff --git a/src/main/java/duke/tasks/TaskListResponse.java b/src/main/java/duke/tasks/TaskListResponse.java
index b49e46785..14a7a3634 100644
--- a/src/main/java/duke/tasks/TaskListResponse.java
+++ b/src/main/java/duke/tasks/TaskListResponse.java
@@ -1,8 +1,7 @@
 package duke.tasks;
 
-import duke.tasks.TaskList;
-
 public class TaskListResponse {
+
     public TaskList taskList;
     public String response;
 
diff --git a/src/main/java/duke/tasks/Todo.java b/src/main/java/duke/tasks/Todo.java
index 30f8c2c3c..15e0c8da8 100644
--- a/src/main/java/duke/tasks/Todo.java
+++ b/src/main/java/duke/tasks/Todo.java
@@ -1,6 +1,7 @@
 package duke.tasks;
 
 public class Todo extends Task{
+
     private TaskType type = TaskType.TODO;
 
     public Todo(String description) {
diff --git a/text-ui-test/EXPECTED.TXT b/text-ui-test/EXPECTED.TXT
index 791744bdc..59f92e79b 100644
--- a/text-ui-test/EXPECTED.TXT
+++ b/text-ui-test/EXPECTED.TXT
@@ -1,8 +1,6 @@
 The file data/duke.txt is not found.A new file data/duke.txt has been created.
 Hello! I'm Duke.
 What can I do for you?
-Command is empty.
-What can I do for you?
 Got it. I've added this task:
 eat cake
 Now you have 1 tasks in the list.
@@ -18,9 +16,9 @@ What can I do for you?
 Nice! I've marked this task as done:
 eat cake
 What can I do for you?
-The description of done cannot be empty.
-What can I do for you?
-The description of todo cannot be empty.
+Here are the matching tasks in your list:
+1. [T][X] eat cake
+2. [D][ ] eat chocolate cake  (by: Friday 2pm)
 What can I do for you?
 Here are the tasks in your list:
 1. [T][X] eat cake
diff --git a/text-ui-test/input.txt b/text-ui-test/input.txt
index 375c6cf2c..322fda1f7 100644
--- a/text-ui-test/input.txt
+++ b/text-ui-test/input.txt
@@ -1,10 +1,8 @@
-eat cake
 todo eat cake
 deadline eat chocolate cake /by Friday 2pm
 event attend cake buffet /at Saturday 5pm
 done 1
-done a
-todo
+find eat
 list
 cake
 bye
\ No newline at end of file

From a87decbfd970b39066434cf09f6f5063a5e6a540 Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Tue, 28 Sep 2021 22:24:53 +0800
Subject: [PATCH 24/25] Customisation and User guide

---
 docs/README.md                                | 153 ++++++++++++++++--
 src/main/java/duke/Parser.java                |   2 +-
 src/main/java/duke/Storage.java               |  10 +-
 src/main/java/duke/Ui.java                    |   6 +-
 .../duke/exceptions/AlreadyDoneException.java |   2 +-
 .../duke/exceptions/DeadlineException.java    |   3 +-
 .../exceptions/DeleteFormatException.java     |   3 +-
 .../duke/exceptions/DeleteRangeException.java |   2 +-
 .../duke/exceptions/DoneFormatException.java  |   3 +-
 .../duke/exceptions/DoneRangeException.java   |   2 +-
 .../java/duke/exceptions/EmptyException.java  |   2 +-
 .../duke/exceptions/EmptyListException.java   |   2 +-
 .../java/duke/exceptions/EventException.java  |   3 +-
 .../duke/exceptions/NotFoundException.java    |   2 +-
 .../java/duke/exceptions/TodoException.java   |   3 +-
 src/main/java/duke/tasks/TaskList.java        |  10 +-
 16 files changed, 171 insertions(+), 37 deletions(-)

diff --git a/docs/README.md b/docs/README.md
index 8077118eb..bb32003a0 100644
--- a/docs/README.md
+++ b/docs/README.md
@@ -1,29 +1,158 @@
 # User Guide
 
-## Features 
+## Command list 
 
-### Feature-ABC
+### `todo` - adds todo task
+### `deadline` - adds deadline task
+### `event` - adds event task
+### `list` - lists all task
+### `find` - find matching tasks
+### `done` - completes task
+### `delete` - deletes task
+### `bye` - exits program
 
-Description of the feature.
+## Usage
 
-### Feature-XYZ
+### `todo` - adds todo task
 
-Description of the feature.
+Adds todo task to the list
 
-## Usage
+Example of usage: 
 
-### `Keyword` - Describe action
+`todo Complete CS2113 lecture quiz`
 
-Describe the action and its outcome.
+Expected outcome:
 
-Example of usage: 
+Displays successfully addition of todo task to the list and the total number of tasks in the list.
+
+```
+Kao got it! (  ｡•̀ᴗ-)✧ Kao has added this task:
+Complete CS2113 lecture quiz
+Now you have 1 tasks in the list.
+```
+
+### `deadline` - adds deadline task
+
+Adds deadline task to the list
+
+Example of usage:
+
+`deadline Complete iP increment /by Thursday 2359`
+
+Expected outcome:
+
+Displays successfully addition of deadline task to the list and the total number of tasks in the list.
+
+```
+Kao got it! (  ｡•̀ᴗ-)✧ Kao has added this task:
+Complete iP increment 
+Now you have 2 tasks in the list.
+```
+
+### `event` - adds event task
+
+Adds event task to the list
+
+Example of usage:
+
+`event Attend CS2113 lecture /at Friday 1400`
+
+Expected outcome:
+
+Displays successfully addition of event task to the list and the total number of tasks in the list.
+
+```
+Kao got it! (  ｡•̀ᴗ-)✧ Kao has added this task:
+Attend CS2113 lecture 
+Now you have 3 tasks in the list.
+```
+
+### `list` - lists all task
+
+Lists the entire task list
+
+Example of usage:
+
+`list`
+
+Expected outcome:
+
+Displays the entire task list
 
-`keyword (optional arguments)`
+```
+Right away! ε=ε=┌( >_<)┘ 
+Kao retrieved the tasks in your list:
+1. [T][ ] Complete CS2113 lecture quiz
+2. [D][ ] Complete iP increment  (by: Thursday 2359)
+3. [E][ ] Attend CS2113 lecture (at: Friday 1400)
+```
+
+### `find` - find matching tasks
+
+Finds matching tasks in the list
+
+Example of usage:
+
+`find CS2113`
+
+Expected outcome:
+
+Display tasks in the task list with the matching keyword
+
+```
+Kao got it! ε=ε=┌( `ー´)┘ 
+Kao retrieved the matching tasks in your list:
+1. [T][ ] Complete CS2113 lecture quiz
+3. [E][ ] Attend CS2113 lecture (at: Friday 1400)
+```
+
+### `done` - completes task
+
+Marks task as complete
+
+Example of usage:
+
+`done 1`
 
 Expected outcome:
 
-Description of the outcome.
+Displays successful completion of the corresponding task
 
 ```
-expected output
+Nice job! (  >ω<)☆ Kao marked this task as done:
+Complete CS2113 lecture quiz
+```
+
+### `delete` - deletes task
+
+Deletes task from the list
+
+Example of usage:
+
+`delete 1`
+
+Expected outcome:
+
+Displays successful deletion of the corresponding task
+
+```
+Alright! ( ・∀・ )ノ Kao removed this task:
+Complete CS2113 lecture quiz
+Now you have 2 tasks in the list.
+```
+
+### `bye` - exits program
+
+Exits and closes the program
+
+Example of usage:
+
+`bye`
+
+Expected outcome:
+
+Shows successful termination of the program
+
 ```
+Bye bye! Kao will be waiting for you ｡:ﾟ( ´°ω°｀ )ﾟ:｡
+```
\ No newline at end of file
diff --git a/src/main/java/duke/Parser.java b/src/main/java/duke/Parser.java
index c9faa8efe..166d3874d 100644
--- a/src/main/java/duke/Parser.java
+++ b/src/main/java/duke/Parser.java
@@ -21,7 +21,7 @@ public class Parser {
     public final String DELETE = "delete";
     public final String BYE = "bye";
 
-    //executes program according to user command
+    //executes program and updates task list according to user command
     public Command parseCommand(TaskList taskList, String line) {
         final String[] splitLine = line.split(" ", 2);
         final String command = splitLine[0];
diff --git a/src/main/java/duke/Storage.java b/src/main/java/duke/Storage.java
index 9ba5b3ee6..c526b6427 100644
--- a/src/main/java/duke/Storage.java
+++ b/src/main/java/duke/Storage.java
@@ -65,15 +65,15 @@ public TaskListResponse initialiseTasks() {
         try {
             loadTasks(taskList);
         } catch (FileNotFoundException e0){
-            response = response + "The file data/duke.txt is not found.";
+            response = response + "Kao cannot find the file data/duke.txt ( ;ŏ﹏ŏ ) ";
             try {
                 createFile();
             } catch (IOException e1) {
-                response = response + "There has been an error creating a new file. ";
+                response = response + "Kao has encountered an error creating a new file ( °ㅂ°╬  )";
             }
-            response = response + "A new file data/duke.txt has been created.";
+            response = response + "Kao will create a new file data/duke.txt for you!";
         } catch (FileFormatException e2) {
-            response = response + "There is a formatting error with the save file.";
+            response = response + "Kao is facing a formatting error with the save file ヽ(  `д´  )ノ";
             taskList.clearList();
         }
         return new TaskListResponse(taskList, response);
@@ -93,7 +93,7 @@ public String write(TaskList taskList) {
         try {
             writeToFile(taskList);
         } catch (IOException e) {
-            return "There has been an error writing to file.";
+            return "Kao has faced an error writing to file ( ; ω ; )";
         }
         return "";
     }
diff --git a/src/main/java/duke/Ui.java b/src/main/java/duke/Ui.java
index 46bab224b..40a5f5795 100644
--- a/src/main/java/duke/Ui.java
+++ b/src/main/java/duke/Ui.java
@@ -11,14 +11,14 @@ public static void printMessage(String line) {
     }
 
     public static void printGreeting() {
-        printMessage("Hello! I'm Duke.");
+        printMessage("Hello there! Kao here! ⸜(˃ ᵕ ˂ )⸝");
     }
 
     public static void printPrompt() {
-        printMessage("What can I do for you?");
+        printMessage( "How can Kao be of assistance? ( •̀ ᗜ •́ )");
     }
 
     public static void printExit() {
-        printMessage("Bye. Hope to see you again soon!");
+        printMessage("Bye bye! Kao will be waiting for you ｡:ﾟ( ´°ω°｀ )ﾟ:｡");
     }
 }
diff --git a/src/main/java/duke/exceptions/AlreadyDoneException.java b/src/main/java/duke/exceptions/AlreadyDoneException.java
index e3b0caa02..df7eef2ec 100644
--- a/src/main/java/duke/exceptions/AlreadyDoneException.java
+++ b/src/main/java/duke/exceptions/AlreadyDoneException.java
@@ -3,7 +3,7 @@
 //used when user tries to complete an already completed task
 public class AlreadyDoneException extends Exception {
 
-    public final String DONE_RESPONSE = "This task is already completed.";
+    public final String DONE_RESPONSE = "Hmm? You already completed that task (/ ￣O￣)/";
 
     @Override
     public String getMessage(){
diff --git a/src/main/java/duke/exceptions/DeadlineException.java b/src/main/java/duke/exceptions/DeadlineException.java
index c4616055d..767876d12 100644
--- a/src/main/java/duke/exceptions/DeadlineException.java
+++ b/src/main/java/duke/exceptions/DeadlineException.java
@@ -3,7 +3,8 @@
 //used when deadline description is in the wrong format
 public class DeadlineException extends Exception {
 
-    public final String DEADLINE_RESPONSE = "The following format must be used: deadline [description] /by [date and time]";
+    public final String DEADLINE_RESPONSE = "Kao needs you to repeat that (。_ 。 )?" +
+            "\nThe following format must be used: deadline [description] /by [date and time]";
 
     @Override
     public String getMessage() {
diff --git a/src/main/java/duke/exceptions/DeleteFormatException.java b/src/main/java/duke/exceptions/DeleteFormatException.java
index 375f11c0d..e2160851d 100644
--- a/src/main/java/duke/exceptions/DeleteFormatException.java
+++ b/src/main/java/duke/exceptions/DeleteFormatException.java
@@ -3,7 +3,8 @@
 //used when delete description is in the wrong format
 public class DeleteFormatException extends Exception {
 
-    public final String DELETE_FORMAT_RESPONSE =  "The following format must be used: delete [index]";
+    public final String DELETE_FORMAT_RESPONSE =  "Could you rephrase that for Kao (￣▽￣*)?" +
+            "\nThe following format must be used: delete [index]";
 
     @Override
     public String getMessage(){
diff --git a/src/main/java/duke/exceptions/DeleteRangeException.java b/src/main/java/duke/exceptions/DeleteRangeException.java
index bfac4906a..63f4f49b3 100644
--- a/src/main/java/duke/exceptions/DeleteRangeException.java
+++ b/src/main/java/duke/exceptions/DeleteRangeException.java
@@ -3,7 +3,7 @@
 //used when task user wants to delete does not exist
 public class DeleteRangeException extends Exception {
 
-    public final String DELETE_RANGE_RESPONSE =  "That task does not exist.";
+    public final String DELETE_RANGE_RESPONSE =  "Kao doesn't see that task anywhere ┐( ・∀・ )┌";
 
     @Override
     public String getMessage(){
diff --git a/src/main/java/duke/exceptions/DoneFormatException.java b/src/main/java/duke/exceptions/DoneFormatException.java
index ba3e8e370..eaf9f45fa 100644
--- a/src/main/java/duke/exceptions/DoneFormatException.java
+++ b/src/main/java/duke/exceptions/DoneFormatException.java
@@ -3,7 +3,8 @@
 //used when done description is in the wrong format
 public class DoneFormatException extends Exception {
 
-    public final String DONE_FORMAT_RESPONSE =  "The following format must be used: done [index]";
+    public final String DONE_FORMAT_RESPONSE =  "Kao doesn't get what you said (  ・ω・)?" +
+            "\nThe following format must be used: done [index]";
 
     @Override
     public String getMessage(){
diff --git a/src/main/java/duke/exceptions/DoneRangeException.java b/src/main/java/duke/exceptions/DoneRangeException.java
index fdafaff6f..a8b0414c9 100644
--- a/src/main/java/duke/exceptions/DoneRangeException.java
+++ b/src/main/java/duke/exceptions/DoneRangeException.java
@@ -3,7 +3,7 @@
 //used when task user wants to complete does not exist
 public class DoneRangeException extends Exception {
 
-    public final String DONE_RANGE_RESPONSE =  "That task does not exist.";
+    public final String DONE_RANGE_RESPONSE =  "Kao doesn't see that task (  ･д･)?";
 
     @Override
     public String getMessage(){
diff --git a/src/main/java/duke/exceptions/EmptyException.java b/src/main/java/duke/exceptions/EmptyException.java
index 8dca54a82..d3ca7c4eb 100644
--- a/src/main/java/duke/exceptions/EmptyException.java
+++ b/src/main/java/duke/exceptions/EmptyException.java
@@ -3,7 +3,7 @@
 //used when user did not input a command
 public class EmptyException extends Exception {
 
-    public final String EMPTY_RESPONSE = "Command is empty.";
+    public final String EMPTY_RESPONSE = "Did you call Kao? (・_・  )";
 
     @Override
     public String getMessage(){
diff --git a/src/main/java/duke/exceptions/EmptyListException.java b/src/main/java/duke/exceptions/EmptyListException.java
index af62c5c6d..a5dfaed2e 100644
--- a/src/main/java/duke/exceptions/EmptyListException.java
+++ b/src/main/java/duke/exceptions/EmptyListException.java
@@ -3,7 +3,7 @@
 //used when user tries the list command even though list is empty
 public class EmptyListException extends Exception {
 
-    public final String EMPTY_LIST_RESPONSE = "The list is empty.";
+    public final String EMPTY_LIST_RESPONSE = "The list is empty (￣ω￣;)";
 
     @Override
     public String getMessage(){
diff --git a/src/main/java/duke/exceptions/EventException.java b/src/main/java/duke/exceptions/EventException.java
index f2789fad9..36ea829ee 100644
--- a/src/main/java/duke/exceptions/EventException.java
+++ b/src/main/java/duke/exceptions/EventException.java
@@ -3,7 +3,8 @@
 //used when event description is in the wrong format
 public class EventException extends Exception {
 
-    public final String EVENT_RESPONSE = "The following format must be used: event [description] /at [date and time]";
+    public final String EVENT_RESPONSE = "Kao doesn't understand you (  ⊙_⊙)?" +
+            "\nThe following format must be used: event [description] /at [date and time]";
 
     @Override
     public String getMessage(){
diff --git a/src/main/java/duke/exceptions/NotFoundException.java b/src/main/java/duke/exceptions/NotFoundException.java
index 9868dd2af..675f79a73 100644
--- a/src/main/java/duke/exceptions/NotFoundException.java
+++ b/src/main/java/duke/exceptions/NotFoundException.java
@@ -3,7 +3,7 @@
 //used when no matching tasks are found from the find command
 public class NotFoundException extends Exception {
 
-    public final String NOT_FOUND_RESPONSE = "There are no matching tasks.";
+    public final String NOT_FOUND_RESPONSE = "Kao couldn't find any matching tasks ╮(・ω・;)╭";
 
     @Override
     public String getMessage(){
diff --git a/src/main/java/duke/exceptions/TodoException.java b/src/main/java/duke/exceptions/TodoException.java
index 49589aa23..ee69226b7 100644
--- a/src/main/java/duke/exceptions/TodoException.java
+++ b/src/main/java/duke/exceptions/TodoException.java
@@ -3,7 +3,8 @@
 //used when todo description is in the wrong format
 public class TodoException extends Exception {
 
-    public final String TODO_RESPONSE = "The following format must be used: todo [description]";
+    public final String TODO_RESPONSE = "Kao is confused (・~・ )?" +
+            "\nThe following format must be used: todo [description]";
 
     @Override
     public String getMessage(){
diff --git a/src/main/java/duke/tasks/TaskList.java b/src/main/java/duke/tasks/TaskList.java
index eab67fb1a..9a863c4a6 100644
--- a/src/main/java/duke/tasks/TaskList.java
+++ b/src/main/java/duke/tasks/TaskList.java
@@ -8,11 +8,11 @@ public class TaskList {
 
     public ArrayList<Task> tasks = new ArrayList<>();
 
-    public String ADDED = "Got it. I've added this task:";
-    public String REMOVED = "Noted. I've removed this task:";
-    public String ACKNOWLEDGED = "Nice! I've marked this task as done:";
-    public String LIST_START = "Here are the tasks in your list:";
-    public String FIND_START = "Here are the matching tasks in your list:";
+    public String ADDED = "Kao got it! (  ｡•̀ᴗ-)✧ Kao has added this task:";
+    public String REMOVED = "Alright! ( ・∀・ )ノ Kao removed this task:";
+    public String ACKNOWLEDGED = "Nice job! (  >ω<)☆ Kao marked this task as done:";
+    public String LIST_START = "Right away! ε=ε=┌( >_<)┘ \nKao retrieved the tasks in your list:";
+    public String FIND_START = "Kao got it! ε=ε=┌( `ー´)┘ \nKao retrieved the matching tasks in your list:";
 
     public String TaskListResponse(String line, int index){
         return line + "\n" + tasks.get(index).getDescription();

From a5be71421dd59ce5e563ddc7cdb6817ef29ed2e5 Mon Sep 17 00:00:00 2001
From: teoziyiivy <e0559117@u.nus.edu>
Date: Wed, 29 Sep 2021 22:00:48 +0800
Subject: [PATCH 25/25] Edit txt files

---
 text-ui-test/EXPECTED.TXT | 61 ++++++++++++++++++++++-----------------
 text-ui-test/input.txt    |  7 ++---
 2 files changed, 37 insertions(+), 31 deletions(-)

diff --git a/text-ui-test/EXPECTED.TXT b/text-ui-test/EXPECTED.TXT
index 59f92e79b..d09585156 100644
--- a/text-ui-test/EXPECTED.TXT
+++ b/text-ui-test/EXPECTED.TXT
@@ -1,30 +1,37 @@
-The file data/duke.txt is not found.A new file data/duke.txt has been created.
-Hello! I'm Duke.
-What can I do for you?
-Got it. I've added this task:
-eat cake
+Kao cannot find the file data/duke.txt ( ;ŏ﹏ŏ ) Kao will create a new file data/duke.txt for you!
+Hello there! Kao here! ⸜(˃ ᵕ ˂ )⸝
+How can Kao be of assistance? ( •̀ ᗜ •́ )
+todo Eat cake
+Kao got it! (  ｡•̀ᴗ-)✧ Kao has added this task:
+Eat cake
 Now you have 1 tasks in the list.
-What can I do for you?
-Got it. I've added this task:
-eat chocolate cake
+How can Kao be of assistance? ( •̀ ᗜ •́ )
+deadline Eat chocolate cake /by Friday 2pm
+Kao got it! (  ｡•̀ᴗ-)✧ Kao has added this task:
+Eat chocolate cake
 Now you have 2 tasks in the list.
-What can I do for you?
-Got it. I've added this task:
-attend cake buffet
+How can Kao be of assistance? ( •̀ ᗜ •́ )
+event Attend cake buffet /at Saturday 5pm
+Kao got it! (  ｡•̀ᴗ-)✧ Kao has added this task:
+Attend cake buffet
 Now you have 3 tasks in the list.
-What can I do for you?
-Nice! I've marked this task as done:
-eat cake
-What can I do for you?
-Here are the matching tasks in your list:
-1. [T][X] eat cake
-2. [D][ ] eat chocolate cake  (by: Friday 2pm)
-What can I do for you?
-Here are the tasks in your list:
-1. [T][X] eat cake
-2. [D][ ] eat chocolate cake  (by: Friday 2pm)
-3. [E][ ] attend cake buffet (at: Saturday 5pm)
-What can I do for you?
-Command is empty.
-What can I do for you?
-Bye. Hope to see you again soon!
+How can Kao be of assistance? ( •̀ ᗜ •́ )
+done 1
+Nice job! (  >ω<)☆ Kao marked this task as done:
+Eat cake
+How can Kao be of assistance? ( •̀ ᗜ •́ )
+find eat
+Kao got it! ε=ε=┌( `ー´)┘
+Kao retrieved the matching tasks in your list:
+1. [T][X] Eat cake
+2. [D][ ] Eat chocolate cake  (by: Friday 2pm)
+How can Kao be of assistance? ( •̀ ᗜ •́ )
+list
+Right away! ε=ε=┌( >_<)┘
+Kao retrieved the tasks in your list:
+1. [T][X] Eat cake
+2. [D][ ] Eat chocolate cake  (by: Friday 2pm)
+3. [E][ ] Attend cake buffet (at: Saturday 5pm)
+How can Kao be of assistance? ( •̀ ᗜ •́ )
+bye
+Bye bye! Kao will be waiting for you ｡:ﾟ( ´°ω°｀ )ﾟ:｡
diff --git a/text-ui-test/input.txt b/text-ui-test/input.txt
index 322fda1f7..567a1aa4e 100644
--- a/text-ui-test/input.txt
+++ b/text-ui-test/input.txt
@@ -1,8 +1,7 @@
-todo eat cake
-deadline eat chocolate cake /by Friday 2pm
-event attend cake buffet /at Saturday 5pm
+todo Eat cake
+deadline Eat chocolate cake /by Friday 2pm
+event Attend cake buffet /at Saturday 5pm
 done 1
 find eat
 list
-cake
 bye
\ No newline at end of file