import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;

/**
 * This class is the GUI implementation of the View component
 * In the Model-View-Presenter pattern.
 */
public class FileSelectorJFrame extends JFrame implements FileSelectorView, ActionListener {

	/**
	 * Default serial version ID.
	 */
	private static final long serialVersionUID = 1L;
	
	/**
	 * The "OK" button for loading the file.
	 */
	private JButton OK;
	
	/**
	 * The cancel button.
	 */
	private JButton cancel;
	
	/**
	 * The information label.
	 */
	private JLabel info;
	
	/**
	 * The contents label.
	 */
	private JLabel contents;
	
	/**
	 * The text field for giving the name of the file
	 * that we want to open.
	 */
	private JTextField input;
	
	/**
	 * A text area that will keep the contents of the file opened.
	 */
	private JTextArea area;
	
	/**
	 * The panel that will hold our widgets.
	 */
	private JPanel panel;
	
	/**
	 * The Presenter component that the frame will interact with
	 */
	private FileSelectorPresenter presenter;
	
	/**
	 * The name of the file that we want to read it's contents.
	 */
	private String fileName;
	
	/**
	 * Constructor.
	 */
	public FileSelectorJFrame() {
		super("File Loader");
		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.setLayout(null);
		this.setBounds(100, 100, 500, 200);
		
		/*
		 * Add the panel.
		 */
		this.panel = new JPanel();
		panel.setLayout(null);
		this.add(panel);
		panel.setBounds(0, 0, 500, 200);
		panel.setBackground(Color.LIGHT_GRAY);
		
		/*
		 * Add the info label.
		 */
		this.info = new JLabel("File Name :");
		this.panel.add(info);
		info.setBounds(30, 10, 100, 30);
		
		/*
		 * Add the contents label. 
		 */
		this.contents = new JLabel("File contents :");
		this.panel.add(contents);
		this.contents.setBounds(30, 100, 120, 30);
		
		/*
		 * Add the text field.
		 */
		this.input = new JTextField(100);
		this.panel.add(input);
		this.input.setBounds(150, 15, 200, 20);
		
		/*
		 * Add the text area.
		 */
		this.area = new JTextArea(100, 100);
		JScrollPane pane = new JScrollPane(area);
		pane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
		pane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);
		this.panel.add(pane);
		this.area.setEditable(false);
		pane.setBounds(150, 100, 250, 80);
		
		/*
		 * Add the OK button.
		 */
		this.OK = new JButton("OK");
		this.panel.add(OK);
		this.OK.setBounds(250, 50, 100, 25);
		this.OK.addActionListener(this);
		
		/*
		 * Add the cancel button. 
		 */
		this.cancel = new JButton("Cancel");
		this.panel.add(this.cancel);
		this.cancel.setBounds(380, 50, 100, 25);
		this.cancel.addActionListener(this);
		
		this.presenter = null;
		this.fileName = null;
	}
	
	@Override
	public void actionPerformed(ActionEvent e) {
		if(e.getSource() == this.OK) {
			this.fileName = this.input.getText();
			presenter.fileNameChanged();
			presenter.confirmed();
		}
		
		else if(e.getSource() == this.cancel) {
			presenter.cancelled();
		}
	}

	@Override
	public void open() {
		this.setVisible(true);
	}

	@Override
	public void close() {
		this.dispose();
	}

	@Override
	public boolean isOpened() {
		return this.isVisible();
	}

	@Override
	public void setPresenter(FileSelectorPresenter presenter) {
		this.presenter = presenter;
	}

	@Override
	public FileSelectorPresenter getPresenter() {
		return this.presenter;
	}

	@Override
	public void setFileName(String name) {
		this.fileName = name;
	}

	@Override
	public String getFileName() {
		return this.fileName;
	}

	@Override
	public void showMessage(String message) {
		JOptionPane.showMessageDialog(null, message);
	}

	@Override
	public void displayData(String data) {
		this.area.setText(data);
	}
}