Justin.java

import java.io.File;
import java.util.Scanner;

public class Justin {

    private Storage storage;
    private TaskList tasks;
    private Ui ui;


    public Justin(String filePath) {

        ui = new Ui();
        this.storage = new Storage(filePath);
        tasks = storage.loadFile(filePath);

    }

    public void run() {

        /*
         * Justin is a chatbot that help users plan and organise tasks
         * Justin stands for JUSt a TImetable(New) : JUSTIN
         *
         * Justin is able to create and manage new tasks
         *   1) Mark tasks off as done
         *   2) Set tasks as To Do's - <keyword> <name>
         *   3) Set tasks as Deadline's - keyword  : <keyword> <name> /by <day>
         *   4) Set tasks as Event's - keyword : <keyword> <name> /at <day time>
         *   5) Supports deletion of completed tasks with command delete <int>
         *
         * Justin also supports viewing the entire tasks list with the command list - keyword : <keyword>
         * To end off the session user can input bye to terminate program - keyword : <keyword>
         *
         * @author Goh Wei Kiat aka github : mrweikiat
         * @version CS2103T AY20/21 Semester 2, Individual Project 'IP'
         */


        Scanner sc = new Scanner(System.in);

        // Starting line for UI
        ui.showWelcomeMessage();
        ui.showHelpMessage();

        // Condition for Duke to stop
        boolean terminate = false;

        //Duke will keep repeating until command given "Bye"
        while (!terminate) {

            String text = sc.nextLine();

            Parser pr = new Parser(text);

            try {
                String command = pr.checkCommand();

                switch (command) {

                    case "BYE":

                        storage.saveFile(tasks, storage.getFilePath());
                        terminate = true; // terminates Duke
                        ui.showEndMessage();
                        break;

                    case "LIST":

                        ui.showListMessage();
                        ui.printList(tasks);
                        break;

                    case "DONE":

                        String num = text.substring(5); // take out the int value of the task to be completed
                        int listNum = Integer.parseInt(num); // changes to int
                        Task hold = tasks.getList().get(listNum - 1);
                        hold.markAsDone();
                        ui.showDoneMessage(tasks, listNum);
                        break;

                    case "DEADLINE":

                        String newText = text.substring(9); // remove deadline from the string text
                        // set delimiter to take out the description of the deadline
                        String description = newText.substring(0, newText.indexOf("/") - 1);
                        // set delimiter to take out date of the deadline
                        String date = newText.substring(newText.indexOf("/") + 4);

                        ui.printLine();
                        tasks.addDeadline(description, date);
                        ui.printLine();

                        break;

                    case "TODO":

                        String descriptionToDo = text.substring(text.indexOf(" ") + 1); // take out the item from the text
                        tasks.addToDo(descriptionToDo);

                        break;

                    case "EVENT":

                        String eventText = text.substring(text.indexOf(" ") + 1); // removing the event to get description
                        // set delimiter to obtain the description and the at
                        String descriptionEvent = eventText.substring(0, eventText.indexOf("/") - 1);
                        String dateEvent = eventText.substring(eventText.indexOf("/") + 4);
                        // splitting the date and time respectively
                        tasks.addEvent(descriptionEvent, dateEvent);

                        break;

                    case "DELETE":

                        String numDelete = text.substring(7); // take out the int value of the task to be completed
                        tasks.delete(numDelete);

                        break;

                    case "FIND": // for level 9

                        String findText = text.substring(text.indexOf(" ")+1); // key for searching
                        ui.printFoundTask(tasks.find(findText));

                        break;

                    default:

                        ui.printLine();
                        System.out.println("added: " + text);
                        ui.printLine();
                        // create new instance of task and add to the list
                        Task holder = new Task(text);
                        tasks.getList().add(holder); // position corresponds to item number

                }
            } catch (JustinException m) {
                ui.printErrorMessage(m.getMessage());
            }


        }
        sc.close();
    }

        public static void main(String[]args){

            String userDir = System.getProperty("user.dir");
            String filePath = userDir + File.separator + "data" + File.separator + "justin.txt";
            new Justin(filePath).run();

        }
}