import javax.swing.*;    // Needed for Swing classes
import java.awt.event.*; // Needed for ActionListener Interface
import java.awt.*; //For grid layout
import javax.swing.JOptionPane; 

/**
 
 */
 
public class TravelGui extends JFrame {
		
private JPanel p1,p2,p3,p4,p5,p6,p7,p8,p9; // To reference a panel
private final int WINDOW_WIDTH = 300;  // Window width
private final int WINDOW_HEIGHT = 320; // Window height
private JLabel aLabel,bLabel,cLabel,dLabel,eLabel,fLabel,gLabel,hLabel; //Labels
private JTextField aField,bField,cField,dField,eField,fField,gField,hField; //Fields
private JButton calculate, reset; //Buttons


public TravelGui() {
      setTitle("Travel Expenses");
      setSize(WINDOW_WIDTH, WINDOW_HEIGHT);
      setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      
       setLayout(new GridLayout(9,1));;//I used the grid layout here.
      
      buildPanel();//Call to buildPanel method.
      setVisible(true);
    }
    
private void buildPanel(){
      aLabel = new JLabel("   Number of days on trip: ");
      bLabel = new JLabel("        Amount of airfare: ");
      cLabel = new JLabel("     Amount of car rental: ");
      dLabel = new JLabel("             Miles Driven: ");
      eLabel = new JLabel("             Parking Fees: ");
      fLabel = new JLabel("                Taxi Fees: ");
      gLabel = new JLabel("  Conference Registration: ");
      hLabel = new JLabel("Lodging Charges Per Night: ");

      aField = new JTextField(10);
      bField = new JTextField(10);
      cField = new JTextField(10);
      dField = new JTextField(10);
      eField = new JTextField(10);
      fField = new JTextField(10);
      gField = new JTextField(10);
      hField = new JTextField(10);
      
      JPanel p1 = new JPanel();
      JPanel p2 = new JPanel();
      JPanel p3 = new JPanel();
      JPanel p4 = new JPanel();
      JPanel p5 = new JPanel();
      JPanel p6 = new JPanel();
      JPanel p7 = new JPanel();
      JPanel p8 = new JPanel();
      JPanel pbutton = new JPanel();
      
      calculate = new JButton("Calculate");
      reset = new JButton("Reset");

      // Add an action listener to the button.
      calculate.addActionListener(new calculate());
      reset.addActionListener(new reset());
      
      p1.add(aLabel);
      p2.add(bLabel);
      p3.add(cLabel);
      p4.add(dLabel);
      p5.add(eLabel);
      p6.add(fLabel);
      p7.add(gLabel);
      p8.add(hLabel);
      
      p1.add(aField);
      p2.add(bField);
      p3.add(cField);
      p4.add(dField);
      p5.add(eField);
      p6.add(fField);
      p7.add(gField);
      p8.add(hField);
      
      pbutton.add(calculate);
      pbutton.add(reset);
      
      add(p1);
      add(p2);
      add(p3);
      add(p4);
      add(p5);
      add(p6);
      add(p7);
      add(p8);
      add(pbutton);
}
    
private class calculate implements ActionListener{
	public void actionPerformed(ActionEvent e)
      {
      	String input;
      	double days, air, car, miles, parking, taxi, registration, lodging;
      	double reimbursable;
      	
      	double DAILY_MEAL_RATE = 37.0;
		double MAX_PARKING_FEES = 10.0;
  		double MAX_TAXI = 20.0;
		double MAX_LODGING_PER_NIGHT = 95.0;
		double MILEAGE_RATE = 0.27;
      	double parkingRe;
      	
      	input = aField.getText();      	
      	days = Double.parseDouble(input);
      	
      	input = bField.getText();
      	air = Double.parseDouble(input);
      	
      	input = cField.getText();
      	car = Double.parseDouble(input);
      	
      	input = dField.getText();
      	miles = Double.parseDouble(input);
      	
      	input = eField.getText();
      	parking = Double.parseDouble(input);
      	
      	input = fField.getText();
      	taxi = Double.parseDouble(input);
      	
      	input = gField.getText();
      	registration = Double.parseDouble(input);
      	
      	input = hField.getText();
      	lodging = Double.parseDouble(input);
      	
      	if(taxi > MAX_PARKING_FEES * days)
      	{
      		parkingRe=3;
      	}
      	/*p arkingRe = minimum parking (MAX_PARKING_FEES * days),
		taxiRe is the minimum of  taxiActual and (MAX_TAXI * days),
		lodgingRe is the minimum of  (lodgingPerNightActual * days) and (MAX_LODGING_PER_NIGHT * days).
      	
      	reimbursable = (days * DAILY_MEAL_RATE) + 
      					parkingRe + taxiRe + (miles * MILEAGE_RATE) + 
      					lodgingRe + car + air + reg;
      													
      		
      		(days * DAILY_MEAL_RATE) + parkingRe + taxiRe +
                        (miles * MILEAGE_RATE) + lodgingRe +
                        carRentalActual + air + reg, */      
      }
	}

private class reset implements ActionListener{
	public void actionPerformed(ActionEvent e)
      {
      	aField.setText("");
      	bField.setText("");
      	cField.setText("");
      	dField.setText("");
      	eField.setText("");
      	fField.setText("");
      	gField.setText("");
      	hField.setText("");
      	}
}
    
public static void main(String[] args){
	TravelGui window = new TravelGui();
}
}