import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.*;

/**
 * class extend Jframe
 * class implements Actionlistner
 */
public class GUI extends JFrame implements ActionListener {
    /**
     * lage GUI
     * four buttons
     * create modelList
     */
    JButton leggTil, fjern, lagre, open;
    DefaultListModel m;
    JList list;

    GUI() {
        this.setSize(450, 400);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setTitle("Bibliotek");
        this.setLayout(new FlowLayout());

        leggTil = new JButton("Legg til en ny bok");
        fjern = new JButton("Fjern bok");
        lagre = new JButton("Lagre");
        open = new JButton("Åpen");
        m = new DefaultListModel();
        list = new JList(m);

        this.add(list);
        this.add(leggTil);
        this.add(fjern);
        this.add(lagre);
        this.add(open);

        leggTil.addActionListener(this);
        lagre.addActionListener(this);
        fjern.addActionListener(this);
        open.addActionListener(this);

        this.setVisible(true);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        /**
         * to add elements to the list
         */
        if (e.getSource().equals(leggTil)) {

            //create an object of Bok class

            Bok b = new Bok();

            String navn = JOptionPane.showInputDialog(this, "" +
                    "Skriv bok navn?");
            b.setNavn(navn);
            String Forfatter = JOptionPane.showInputDialog(this, "" +
                    "Skriv forfatters navn?");
            b.setForfatter(Forfatter);
            int sider = Integer.parseInt(JOptionPane.showInputDialog(this, "" +
                    "Skriv antall sider!"));
            b.setSider(sider);
            m.addElement(b);
        }

        /**
         * to save the added elements
         */
        if (e.getSource().equals(lagre)) {
            try {
                FileOutputStream fileOutputStream = new FileOutputStream("Bibliotek.txt");
                ObjectOutputStream o = new ObjectOutputStream(fileOutputStream);
                o.writeObject(m);
                o.close();
                fileOutputStream.close();
            } catch (FileNotFoundException e1) {
                e1.printStackTrace();
            } catch (IOException e1) {
                e1.printStackTrace();
            }
        }

        /**
         * to open the saved lists
         */
        if (e.getSource().equals(open)) {
            try {
                FileInputStream f = new FileInputStream("Bibliotek.txt");
                ObjectInputStream o = new ObjectInputStream(f);
                m = (DefaultListModel) o.readObject();
                list.setModel(m);
            } catch (FileNotFoundException e1) {
                e1.printStackTrace();
            } catch (IOException e1) {
                e1.printStackTrace();
            } catch (ClassNotFoundException e1) {
                e1.printStackTrace();
            }
        }

        /**
         * to remov one or more selected from the list
         */
        if (e.getSource().equals(fjern)) {
            if (list.getSelectedIndex() != -1) {
                m.remove(list.getSelectedIndex());

            }
        }
    }
}