import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class View {
    private Controller controller;
    private JFrame vindu;
    private JPanel hovedpanel;
    private JPanel operasjonspanel;
    private JPanel numpad;
    private JTextField beregningsfelt;
    private JButton ferdigKnapp;
    private JButton sletteKnapp;
    private Font tekstfont;

    public View(Controller controller) {
        vindu = new JFrame("Kalkulator");
        hovedpanel = new JPanel(new BorderLayout(10, 10));
        operasjonspanel = new JPanel();
        numpad = new JPanel(new GridLayout(4, 3, 5, 5));
        beregningsfelt = new JTextField();
        ferdigKnapp = new JButton("Done");
        sletteKnapp = new JButton("<x=");
        tekstfont = new Font("Times New Roman", Font.PLAIN, 20);

        this.controller = controller;
    }

    public void init() {
        try {
            UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName());
        } catch (Exception e) {
            System.exit(1);
        }

        vindu.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        vindu.setPreferredSize(new Dimension(700, 900));

        beregningsfelt.setFocusable(false);
        beregningsfelt.setPreferredSize(new Dimension(150, 80));
        beregningsfelt.setFont(tekstfont);

        operasjonspanel.add(new NumButton(" + "));
        operasjonspanel.add(new NumButton(" - "));
        operasjonspanel.add(new NumButton(" * "));
        operasjonspanel.add(new NumButton(" / "));
        operasjonspanel.add(beregningsfelt);
        
        ferdigKnapp.setPreferredSize(new Dimension(80, 80));
        sletteKnapp.setPreferredSize(new Dimension(80, 80));

        ferdigKnapp.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                String uttrykk = beregningsfelt.getText();
                controller.beregnUttrykk(uttrykk);
            }
        });

        sletteKnapp.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                String uttrykk = beregningsfelt.getText();
                if (uttrykk.length() > 0) {
                    beregningsfelt.setText(uttrykk.substring(0, uttrykk.length() - 1));
                }   
            }
        });

        operasjonspanel.add(ferdigKnapp);
        operasjonspanel.add(sletteKnapp);


        numpad.setPreferredSize(new Dimension(300, 400));
        for (int i = 9; i >= 0; i--) {
            numpad.add(new NumButton(i + ""));
        }

        numpad.add(new NumButton("."));

        vindu.add(operasjonspanel, BorderLayout.NORTH);
        vindu.add(numpad, BorderLayout.CENTER);

        vindu.pack();
        vindu.setLocationRelativeTo(null);
        vindu.setVisible(true);
    }

    public JTextField hentBeregningsfelt() {
        return beregningsfelt;
    }

    private class NumButton extends JButton {
        public NumButton(String num) {
            super(num);
            setBackground(Color.WHITE);
            setPreferredSize(new Dimension(80, 80));
            setFont(tekstfont);

            addActionListener(new ActionListener() {
                @Override
                public void actionPerformed(ActionEvent e) {
                    beregningsfelt.setText(beregningsfelt.getText() + num);
                }
            });
        }


    }
}