package cmpt213.assignment4.packagedeliveries.client.control;

import cmpt213.assignment4.packagedeliveries.client.gson.extras.RuntimeTypeAdapterFactory;
import cmpt213.assignment4.packagedeliveries.client.model.BookPackage;
import cmpt213.assignment4.packagedeliveries.client.model.ElectronicPackage;
import cmpt213.assignment4.packagedeliveries.client.model.PackageInfo;
import cmpt213.assignment4.packagedeliveries.client.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.NoSuchFileException;
import java.nio.file.Paths;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.ArrayList;
import java.util.Collections;

/**
 * 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<>();

    private static PackageDeliveriesTracker instance;

    public static PackageDeliveriesTracker getInstance() {
        if (instance == null) {
            instance = new PackageDeliveriesTracker();
        }
        return instance;
    }

    public void addPackage(PackageInfo p) {
        packageList.add(p);
        Collections.sort(packageList);
    }

    /**
     * It saves the packageList to a file.
     */
    public 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
     */
    public 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 (NoSuchFileException e) {
            createFile();
            //throw new RuntimeException(e);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    private void createFile() {
        System.out.println("CreateFile");
        try {
            File packages = new File(fileName);
            if(packages.createNewFile()) {
                System.out.println("New file list.json created");
            }
        }
        catch (IOException e) {
            System.out.println("No file exists, creating a new file");
            e.printStackTrace();
        }
    }

    public ArrayList<String> getAllPackages() {
        ArrayList<String> b = new ArrayList<>();
        if (packageList.size() == 0) {
            b.add("No packages to show");
        } else {
            Collections.sort(packageList);
            for (int i = 0; i < packageList.size(); i++) {
                String bString = ("Package #" + (i + 1)) + "\n" + packageList.get(i) + "\n\n";
                b.add(bString);
            }
        }
        return b;
    }

    /**
     * This function takes in a list of packages, a boolean for whether or not the user wants to see
     * packages that are due, and a boolean for whether or not the user wants to see all packages. It
     * then returns a list of packages that are sorted by their expected delivery date
     *
     * @param pList the list of packages to be sorted
     * @param due   true if you want to sort the list by due date, false if you want to sort the list by
     *              expected date
     * @return An ArrayList of PackageInfo objects.
     */
    //due=true returns overdue packages, else upcoming packages
    public ArrayList<PackageInfo> sortList(ArrayList<PackageInfo> pList, boolean due) {
        ArrayList<PackageInfo> sortedList = new ArrayList<>();
        LocalDateTime today = LocalDateTime.now();
        DateTimeFormatter format = DateTimeFormatter.ofPattern("yyy-MM-dd HH:mm");
        today.format(format);
        for (int i = 0; i < pList.size(); i++) {
            PackageInfo p = pList.get(i);
            if (!p.getDelivered()) {
                if (due && today.isAfter(p.getExpectedDate())) {
                    sortedList.add(p);
                } else if (!due && today.isBefore(p.getExpectedDate())) {
                    sortedList.add(p);
                }
            }
        }
        Collections.sort(sortedList);
        return sortedList;
    }

    public ArrayList<String> overDuePackages() {
        ArrayList<String> b = new ArrayList<>();
        ArrayList<PackageInfo> overdue = sortList(packageList, true);
        if (overdue.size() == 0) {
            b.add("no overdue packages to show");
        }
        for (int i = 0; i < overdue.size(); i++) {
            String bString = ("Package #" + (i + 1)) + "\n" + overdue.get(i) + "\n\n";
            b.add(bString);
        }
        return b;
    }

    public ArrayList<String> upcomingPackages() {
        ArrayList<String> b = new ArrayList<>();
        ArrayList<PackageInfo> upcoming = sortList(packageList, false);
        if (upcoming.size() == 0) {
            b.add("no upcoming packages to show");
        }
        for (int i = 0; i < upcoming.size(); i++) {
            String bString = ("Package #" + (i + 1)) + "\n" + upcoming.get(i) + "\n\n";
            b.add(bString);
        }
        return b;
    }

    public void removePcakage(int i) {
        packageList.remove(i);
    }

    public boolean isDelivered(int i) {
        return packageList.get(i).getDelivered();
    }

    public void setDelivered(int i) {
        packageList.get(i).setDelivered(true);
    }

}