cmpt213-a2/src/cmpt213/assignment2/packagedeliveriestracker/textui/PackageDeliveriesTracker.java

package cmpt213.assignment2.packagedeliveriestracker.textui;

import cmpt213.assignment2.packagedeliveriestracker.gson.extras.RuntimeTypeAdapterFactory;
import cmpt213.assignment2.packagedeliveriestracker.model.BookPackage;
import cmpt213.assignment2.packagedeliveriestracker.model.ElectronicPackage;
import cmpt213.assignment2.packagedeliveriestracker.model.PackageInfo;
import cmpt213.assignment2.packagedeliveriestracker.model.PerishablePackage;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.TypeAdapter;
import com.google.gson.reflect.TypeToken;
import com.google.gson.stream.JsonReader;
import com.google.gson.stream.JsonWriter;

import java.io.*;
import java.lang.reflect.Type;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.time.LocalDateTime;
import java.util.ArrayList;
import java.util.Scanner;

/**
 * It's a class that contains a main method that creates a TextMenu object, loads a list of packages
 * from a file, and then loops through a menu of options until the user chooses to quit
 */
public class PackageDeliveriesTracker {
    private static final String fileName = "list.json";
    private static final RuntimeTypeAdapterFactory<PackageInfo> r = RuntimeTypeAdapterFactory.of(PackageInfo.class, "type")
            .registerSubtype(BookPackage.class, "book")
            .registerSubtype(PerishablePackage.class, "perishable")
            .registerSubtype(ElectronicPackage.class, "electronic");
    private static final Gson gson = new GsonBuilder().registerTypeAdapter(LocalDateTime.class,
            new TypeAdapter<LocalDateTime>() {
                @Override
                public void write(JsonWriter jsonWriter,
                                  LocalDateTime localDateTime) throws IOException {
                    jsonWriter.value(localDateTime.toString());
                }

                @Override
                public LocalDateTime read(JsonReader jsonReader) throws IOException {
                    return LocalDateTime.parse(jsonReader.nextString());
                }
            }).registerTypeAdapterFactory(r).create();
    private static ArrayList<PackageInfo> packageList = new ArrayList<>();

    /**
     * It saves the packageList to a file.
     */
    private static void save() {
        try {
            Writer w = new FileWriter(fileName);
            gson.toJson(packageList, w);
            w.flush();
            w.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /**
     * It reads the json file, converts it to a list of PackageInfo objects, and then sets the type of
     * each object to the appropriate type
     */
    private static void load() {
        File file = new File(fileName);
        try {
            String json = Files.readString(Paths.get(fileName));
            Type lType = new TypeToken<ArrayList<PackageInfo>>() {
            }.getType();
            packageList = gson.fromJson(json, lType);
            for (PackageInfo p : packageList) {
                if (p instanceof BookPackage) {
                    p.setType("book");
                } else if (p instanceof PerishablePackage) {
                    p.setType("perishable");
                } else if (p instanceof ElectronicPackage) {
                    p.setType("electronic");
                }
            }
            System.out.println("packages loaded");
        } catch (FileNotFoundException e) {
            System.out.println("no packages to load");
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * This function is the main function of the program. It creates a TextMenu object, loads the
     * packages from the file, displays the menu, and then waits for the user to input a number between
     * 1 and 7. If the user inputs a number outside of that range, the program will display an error
     * message. If the user inputs 7, the program will save the packages to the file and exit. If the
     * user inputs a number between 1 and 6, the program will call the corresponding function in the
     * TextMenu class
     */
    public static void main(String[] args) {
        TextMenu menu = new TextMenu();
        load();
        do {
            menu.display();
            System.out.println("choose an option between 1 and 7:");
            Scanner scan = new Scanner(System.in);
            int option = Integer.parseInt(scan.nextLine());
            if (option > 7 || option < 1) {
                System.out.println("invalid input");
            } else if (option == 7) {
                save();
                System.out.print("packages saved");
                break;
            } else {
                switch (option) {
                    case 1:
                        menu.list(packageList);
                        break;
                    case 2:
                        menu.add(packageList);
                        break;
                    case 3:
                        menu.remove(packageList);
                        break;
                    case 4:
                        menu.overDueList(packageList);
                        break;
                    case 5:
                        menu.upcomingList(packageList);
                        break;
                    case 6:
                        menu.markDelivered(packageList);
                }
            }
        }
        while (true);
    }
}