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

public class ViewOne extends JInternalFrame implements ActionListener {

	private JPanel jpRec = new JPanel();
	private JLabel lbNo, lbName, lbDate, lbBal;
	private JTextField txtNo, txtName, txtDate, txtBal, txtRec;
	private JButton btnFirst, btnBack, btnNext, btnLast;

	private int recCount = 0;
	private int rows = 0;
	private	int total = 0;

	//String Type Array use to Load Records From File.
	private String records[][] = new String [500][6];

	private FileInputStream fis;
	private DataInputStream dis;

	ViewOne () {

		// super(Title, Resizable, Closable, Maximizable, Iconifiable)
		super ("View Account Holders", false, true, false, true);
		setSize (350, 235);

		jpRec.setLayout (null);

		lbNo = new JLabel ("Account No:");
		lbNo.setForeground (Color.black);
		lbNo.setBounds (15, 20, 80, 25);
	        lbName = new JLabel ("Person Name:");
		lbName.setForeground (Color.black);
	        lbName.setBounds (15, 55, 80, 25);
		lbDate = new JLabel ("Last Transaction:");
		lbDate.setForeground (Color.black);
		lbDate.setBounds (15, 90, 100, 25);
		lbBal = new JLabel ("Balance:");
		lbBal.setForeground (Color.black);
		lbBal.setBounds (15, 125, 80, 25);

		txtNo = new JTextField ();
		txtNo.setHorizontalAlignment (JTextField.RIGHT);
		txtNo.setEnabled (false);
		txtNo.setBounds (125, 20, 200, 25);
		txtName = new JTextField ();
		txtName.setEnabled (false);
		txtName.setBounds (125, 55, 200, 25);
		txtDate = new JTextField ();
		txtDate.setEnabled (false);
		txtDate.setBounds (125, 90, 200, 25);
		txtBal = new JTextField ();
		txtBal.setHorizontalAlignment (JTextField.RIGHT);
		txtBal.setEnabled (false);
		txtBal.setBounds (125, 125, 200, 25);

		//Aligninig The Navigation Buttons.
		btnFirst = new JButton ("<<");
		btnFirst.setBounds (15, 165, 50, 25);
		btnFirst.addActionListener (this);
		btnBack = new JButton ("<");
		btnBack.setBounds (65, 165, 50, 25);
		btnBack.addActionListener (this);
		btnNext = new JButton (">");
		btnNext.setBounds (225, 165, 50, 25);
		btnNext.addActionListener (this);
		btnLast = new JButton (">>");
		btnLast.setBounds (275, 165, 50, 25);
		btnLast.addActionListener (this);
		txtRec = new JTextField ();
		txtRec.setEnabled (false);
		txtRec.setHorizontalAlignment (JTextField.CENTER);
		txtRec.setBounds (115, 165, 109, 25);

		//Adding the All the Controls to Panel.
		jpRec.add (lbNo);
		jpRec.add (txtNo);
		jpRec.add (lbName);
		jpRec.add (txtName);
		jpRec.add (lbDate);
		jpRec.add (txtDate);
		jpRec.add (lbBal);
		jpRec.add (txtBal);
		jpRec.add (btnFirst);
		jpRec.add (btnBack);
		jpRec.add (btnNext);
		jpRec.add (btnLast);
		jpRec.add (txtRec);

		//Adding Panel to Window.
		getContentPane().add (jpRec);

		//Load All Existing Records in Memory and Display them on Form.
		populateArray ();
		showRec (0);

		//In the End Showing the New Account Window.
		setVisible (true);

	}

	//Function use By Buttons of Window to Perform Action as User Click Them.
	public void actionPerformed (ActionEvent ae) {

		Object obj = ae.getSource();

		if (obj == btnFirst) {
			recCount = 0;
			showRec (recCount);
		}
		else if (obj == btnBack) {
			recCount = recCount - 1;
			if (recCount < 0) {
				recCount = 0;
				showRec (recCount);
				JOptionPane.showMessageDialog (this, "You are on First Record.",
						"BankSystem - 1st Record", JOptionPane.PLAIN_MESSAGE);
			}
			else {
				showRec (recCount);
			}
		}
		else if (obj == btnNext) {
			recCount = recCount + 1;
			if (recCount == total) {
				recCount = total - 1;
				showRec (recCount);
				JOptionPane.showMessageDialog (this, "You are on Last Record.",
						"BankSystem - End of Records", JOptionPane.PLAIN_MESSAGE);
			}
			else {
				showRec (recCount);
			}
		}
		else if (obj == btnLast) {
			recCount = total - 1;
			showRec (recCount);
		}

	}

	//Function use to load all Records from File when Application Execute.
	void populateArray () {

		try {
			fis = new FileInputStream ("Bank.dat");
			dis = new DataInputStream (fis);
			//Loop to Populate the Array.
			while (true) {
				for (int i = 0; i < 6; i++) {
					records[rows][i] = dis.readUTF ();
				}
				rows++;
			}
		}
		catch (Exception ex) {
			total = rows;
			if (total == 0) {
				JOptionPane.showMessageDialog (null, "Records File is Empty.\nEnter Records First to Display.",
							"BankSystem - EmptyFile", JOptionPane.PLAIN_MESSAGE);
				btnEnable ();
			}
			else {
				try {
					dis.close();
					fis.close();
				}
				catch (Exception exp) { }
			}
		}

	}

	//Function which display Record from Array onto the Form.
	public void showRec (int intRec) {

		txtNo.setText (records[intRec][0]);
		txtName.setText (records[intRec][1]);
		txtDate.setText (records[intRec][2] + ", " + records[intRec][3] + ", " + records[intRec][4]);
		txtBal.setText (records[intRec][5]);
		if (total == 0) { 
			txtRec.setText (intRec + "/" + total); //Showing Record No. and Total Records.
			txtDate.setText ("");
		}
		else {
			txtRec.setText ((intRec + 1) + "/" + total); //Showing Record No. and Total Records.
		}

	}

	//Function use to Lock all Buttons of Window.
	void btnEnable () {

		btnFirst.setEnabled (false);
		btnBack.setEnabled (false);
		btnNext.setEnabled (false);
		btnLast.setEnabled (false);

	}

}