add DateTime functionality

src/main/java/DatedTask.java

@@ -0,0 +1,33 @@
+import java.util.Optional;
+import java.time.LocalDate;
+import java.time.format.DateTimeParseException;
+import java.time.format.DateTimeFormatter;
+
+public class DatedTask extends Task{
+    private Optional<LocalDate> date;
+    private String detail;
+
+    public DatedTask(String description, String date) {
+        super(description);
+        this.detail = date;
+        try {
+            CharSequence dateCharSeq = new StringBuffer(date.strip());
+            LocalDate localDate = LocalDate.parse(dateCharSeq);
+            this.date = Optional.of(localDate);
+        } catch (DateTimeParseException e) {
+            this.date = Optional.empty();
+        }
+    }
+
+    protected Optional<LocalDate> getBy() {
+        return date;
+    }
+
+    protected String getDateOrDetail() {
+        if (date.isEmpty()) {
+            return detail;
+        }
+        return date.get().format(DateTimeFormatter.ofPattern("dd/MM/yyyy"));
+    }
+
+}

src/main/java/Deadline.java

@@ -0,0 +1,14 @@
+public class Deadline extends DatedTask {
+
+
+    public Deadline(String description, String deadline) {
+        super(description, deadline);
+
+    }
+
+    @Override
+    public String toString() {
+        return String.format("[D]%s (at: %s)", super.toString(), 
+                super.getDateOrDetail());
+    }
+}

src/main/java/Duke.java

@@ -1,10 +1,40 @@
+import java.util.Scanner;
+
+
 public class Duke {
+    /**
+     * Main method which handles initial and closing interactions.
+     * @param args
+     */
     public static void main(String[] args) {
-        String logo = " ____        _        \n"
-                + "|  _ \\ _   _| | _____ \n"
-                + "| | | | | | | |/ / _ \\\n"
-                + "| |_| | |_| |   <  __/\n"
-                + "|____/ \\__,_|_|\\_\\___|\n";
-        System.out.println("Hello from\n" + logo);
+
+        Output.introduceDuke();
+        Output.greetUser();
+
+        run();
+
+        Output.byeUser();
     }
+
+
+    /**
+     *  Method containing the continuous while loop that parses user inputs and handles interactions accordingly
+     *  Also initialises the task list. Attempts to retrieve a stored task list, if any.
+     */
+    private static void run() {
+
+        Scanner scan = new Scanner(System.in);
+
+        TaskManager manager = RetrieveList.retrieveList();
+
+        while(manager.parseInput(scan.nextLine())) {
+            Output.printBreak();
+            Output.printEmptyLine();
+        }
+
+        scan.close();
+    }
+
+
+
 }

src/main/java/Event.java

@@ -0,0 +1,14 @@
+public class Event extends DatedTask {
+
+
+    public Event(String description, String event) {
+        super(description, event);
+    }
+
+    @Override
+    public String toString() {
+        return String.format("[E]%s (at: %s)", super.toString(), 
+                super.getDateOrDetail());
+    }
+
+}

src/main/java/Output.java

@@ -0,0 +1,87 @@
+public class Output {
+
+    /**
+     * Prints a standard breakline meant to break up sections of text
+     */
+    public static void printBreak() {
+        System.out.println("  ________________________________________________________");
+    }
+
+    /**
+     * Prints out the logo to introduce the program
+     */
+    public static void introduceDuke() {
+        String logo = " ____        _        \n"
+                + "|  _ \\ _   _| | _____ \n"
+                + "| | | | | | | |/ / _ \\\n"
+                + "| |_| | |_| |   <  __/\n"
+                + "|____/ \\__,_|_|\\_\\___|\n";
+        System.out.println("Hello from\n" + logo);
+        printBreak();   
+    }
+
+    /**
+     * Standard greeting that indicates program start / ready to recieve user input
+     */
+    public static void greetUser() {
+        System.out.println(" Hello! I'm Duke");
+        System.out.println(" What can I do for you?");
+        printBreak();
+    }
+
+    /**
+     * Standard farewell that marks end of program
+     */
+    public static void byeUser() {
+        printBreak();
+        System.out.println(" Bye. Hope to see you again soon!");
+        printBreak();
+
+    }
+
+    /**
+     * Informs user of a caught error by providing a message with proper indentation/formating.
+     */
+    public static void printError(String s) {
+        Output.printBreak();
+        System.out.println("    " + s);
+    }
+
+    public static void printEmptyLine() {
+        System.out.println("\n");
+    }
+
+    protected static void printDeletedTask(String taskString) {
+        System.out.println(String.format("  Noted. I've removed this task: \n    %s", taskString));
+    }
+
+    protected static void printAddedTask(String taskString) {
+        System.out.println("Got it. I've added this task :");
+        System.out.println("   " + taskString);
+    }
+
+    protected static void printCompletedTask(String taskString) {
+        System.out.println("Nice! I've marked this task as done:");
+        System.out.println("     " + taskString);
+    }
+
+    protected static void printTaskList (String listString) {
+        System.out.println("Here are the tasks in your list:");
+        System.out.println(listString);
+    }
+
+    protected static void printMatches (String matchList) {
+        printBreak();
+        if (matchList.length() == 0) {
+            System.out.println("  Sorry! I couldn't find any matches.");
+            return;
+        }
+
+        System.out.println("Here are the matching tasks in your list:");
+        System.out.println(matchList);
+    }
+
+    protected static void printTaskCount(int count) {
+        System.out.println(String.format("  Now you have %s tasks in the list.", count));
+    }
+}

src/main/java/RetrieveList.java

@@ -0,0 +1,78 @@
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.InvalidPathException;
+import java.nio.file.Files;
+import java.io.IOException;
+
+
+public class RetrieveList {
+    private static int TASK_TYPE_INDEX = 1;
+    private static int TASK_STATUS_INDEX = 4;
+    private static int TASK_DESCRIPTION_INDEX = 7;
+
+
+    /**
+     * RetrieveList attempts to load the previously stored list in [user.home]/duke-data.txt
+     * @return TaskManager object with pre-loaded list or an empty one if stored list could not be retrieved.
+     */
+    public static TaskManager retrieveList() {
+        try {
+            String home = System.getProperty("user.home");
+            Path path = Paths.get(home, "duke-data.txt");
+            return parseTxt(path);
+        } catch (InvalidPathException e) {
+            Output.printError("Seems like this is your first time using Duke.");
+            return new TaskManager();
+        }
+    }
+
+    private static TaskManager parseTxt(Path path) {
+        TaskList tasks = new TaskList();
+        try {
+            Files.lines(path).forEachOrdered(line -> {
+                char key = line.charAt(TASK_TYPE_INDEX);
+                Character statusChar = line.charAt(TASK_STATUS_INDEX);
+                String description = line.substring(TASK_DESCRIPTION_INDEX);
+
+                boolean status = false;
+                if (statusChar.equals('\u2713')) {
+                    status = true;
+                }
+
+                switch (key) {
+                    case 'T':
+                        addTodo(tasks, description, status);
+                        break;
+                    case 'D':
+                        addDeadline(tasks, description, status);
+                        break;
+                    case 'E':
+                        addEvent(tasks, description, status);
+                }
+
+            });
+            return new TaskManager(tasks);
+        } catch (IOException e) {
+            return new TaskManager();
+        }
+
+    }
+
+    private static void addTodo(TaskList tasks, String description, boolean status) {
+        tasks.addTodo(description.strip(), status);
+    }
+
+    private static void addDeadline(TaskList tasks, String description, boolean status) {
+        String cleanString = description.replace(')', ' ').replace('(', ' ').replaceFirst("by", " ");
+        String[] inputs = cleanString.split(":", 2);
+        tasks.addDeadline(inputs[0].strip(), inputs[1].strip(), status);
+    }
+
+    private static void addEvent(TaskList tasks, String description, boolean status) {
+        // dev note: "repeated code"
+        String cleanString = description.replace(')', ' ').replace('(', ' ').replaceFirst("at", " ");
+        String[] inputs = cleanString.split(":", 2);
+        tasks.addEvent(inputs[0].strip(), inputs[1].strip(), status);
+    }
+
+}

src/main/java/SaveList.java

@@ -0,0 +1,25 @@
+import java.nio.file.Path;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.util.ArrayList;
+
+
+public class SaveList {
+
+    protected static void saveListToFile(Path path, ArrayList<Task> list) {
+        try {
+            FileWriter writer = new FileWriter(path.toString());
+            list.forEach(x -> {
+                try {
+                    writer.write(x.toString() + "\n");
+                } catch (IOException e) {
+                    Output.printError("A task could not be saved: " + x.toString());
+                }
+            });
+            writer.close();
+        } catch (IOException e) {
+            Output.printError("Not able to open or close the filewriter");
+        }
+    }
+
+}

src/main/java/StringPair.java

@@ -0,0 +1,9 @@
+public final class StringPair {
+    public String first;
+    public String second;
+
+    public StringPair(String first, String second) {
+        this.first = first;
+        this.second = second;
+    }
+}

src/main/java/Task.java

@@ -0,0 +1,33 @@
+public class Task {
+    protected String description;
+    private boolean isComplete;
+
+    public Task(String description) {
+        this.description = description;
+        this.isComplete = false;
+    }
+
+    @Override
+    public String toString() {
+        return this.getCompletionStatusIcon() + " " + this.description; 
+    }
+
+    protected boolean markAsComplete() {
+        this.isComplete = true;
+        return this.isComplete;
+    }
+
+    protected boolean checkIsComplete() {
+        return this.isComplete;
+    }
+
+    private String getCompletionStatusIcon() {
+        return (isComplete ? "[\u2713]" : "[\u2718]");
+    }
+
+    protected String getDescription() {
+        return this.description;
+    }
+
+
+}