/*Imports*/

import java.applet.Applet;
import java.util.*;
import java.awt.*;

public class reg extends Applet {

/*Declaring Variables*/

	TextField name, SSN, c1, c2, c3, c4, c5, course;
	String courseText;
	int recNum, z, x, y, matches, paintRecord;
	Button accept, search;
	Graphics g;
	Panel p, p1;
	Font font;

/*Initalizing Variables*/

	String[][] record = new String[20][7];
	String[][] roll = new String[20][2];
	int numberOfRecords = 0;
	int process = 5;

	public void init () {

/*GUI setup*/

		setLayout(new BorderLayout());
		Panel p = new Panel();
		Panel p1 = new Panel();
		p.setLayout(new GridLayout(15, 1));
		p.add(new Label("Your Name"));
		name = new TextField(20);
		p.add(name);
		p.add(new Label("SS Number (No dashes!)"));
		SSN = new TextField(20);
		p.add(SSN);
		p.add(new Label("First Class"));
		c1 = new TextField(20);
		p.add(c1);
		p.add(new Label("Second Class"));
		c2 = new TextField(20);
		p.add(c2);
		p.add(new Label("Third Class"));
		c3 = new TextField(20);
		p.add(c3);
		p.add(new Label("Fourth Class"));
		c4 = new TextField(20);
		p.add(c4);
		p.add(new Label("Fifth Class"));
		c5 = new TextField(20);
		p.add(c5);
		Button accept = new Button("Accept");
		p.add(accept);
		p1.setLayout(new GridLayout(1,3));
		p1.add(new Label("List students in class"));
		course = new TextField(20);
		p1.add(course);
		Button search = new Button("Search");
		p1.add(search);
		add("West", p);
		add("South", p1);

/*Intialzing of record fields*/

		for (x = 0; x <= 19; x++) {

			for (y = 0; y <= 6; y++) {

				record[x][y] = "";
			
			}

		}

		process = 5;
		repaint();

	}

	public boolean action(Event e, Object arg) {

/*If the accept button is pressed...*/

		if (arg == "Accept") {

			checkEntry();

		}
		
/*If the search button is pressed...*/

		if (arg == "Search") {

			searchRoll();

		}

		return super.action(e, arg);

	}

	public void checkEntry() {

/*Intialzing local variables*/

		String nameCompare, SSNCompare;
		boolean foundRecord = false;

/*Pulls the name that is entered in the GUI and checks to make sure it's valid*/

		String compare = name.getText();
		if (compare.length() == 0) {

			process = 1;
			repaint();

		}

		else {

/*Pulls the SSN that is entered in the GUI and checks to make sure it's valid*/

			compare = SSN.getText();
			if (compare.length() != 9 || intFromTextField(SSN) == 0) {

 				process = 2;
				repaint();

			}

			else {

/*Pulls the first class that is entered in the GUI and checks to make sure it's valid*/

				compare = c1.getText();
				if (compare.length() == 0) {

					process = 3;
					repaint();

				}

				else {

/*Enters record if this is the first student to register.*/

					if (numberOfRecords == 0) {
		
						addRecord();

					}
	
					else {

/*Sets local variables to check for occurance of SSN and name in previous records*/

						nameCompare = name.getText();
						SSNCompare = SSN.getText();
						foundRecord = false;

/*Looks through all previous records to find occurance of SSN and name*/

						for (z = 0; z <= (numberOfRecords - 1); z++) {

							if (nameCompare.equalsIgnoreCase(record[z][0]) && SSNCompare.equalsIgnoreCase(record[z][1])) {

								recNum = z;
								foundRecord = true;
								replaceRecord();

/*If match is found, goes to replace record with new classes*/

							}
						
						}
			
/*If no match is found, new record added*/

						if (foundRecord == false) {

							addRecord();

						}

					}

/*Prints out confrimation screen*/

					process = 4;
					repaint();

				}

			}

		}

	}
		
	public void addRecord() {

/*Adds new record to table*/

		record[numberOfRecords][0] = name.getText();
		record[numberOfRecords][1] = SSN.getText();
		record[numberOfRecords][2] = c1.getText();

/*Makes sure there is a class entered before entering the field into the record*/

		String compare = c2.getText();
		if (compare.length() != 0) {

			record[numberOfRecords][3] = c2.getText();
			
			compare = c3.getText();
			if (compare.length() != 0) {

				record[numberOfRecords][4] = c3.getText();

				compare = c4.getText();
				if (compare.length() != 0) {

					record[numberOfRecords][5] = c4.getText();
	
					compare = c5.getText();
					if (compare.length() != 0) {

						record[numberOfRecords][6] = c5.getText();

					}

				}

			}

		}
		
/*Sets a variable for the printing of the screen and increases the number of records talley*/

		paintRecord = numberOfRecords;
		numberOfRecords++;

	}

	public void replaceRecord() {

/*Replaces the duplicate record with the new information*/

		record[recNum][0] = name.getText();
		record[recNum][1] = SSN.getText();
		record[recNum][2] = c1.getText();

/*If field is empty, makes sure that record field is empty also*/

		String compare = c2.getText();
		if (compare.length() != 0) {

			record[recNum][3] = c2.getText();

		}

		else {

			record[recNum][3] = "";

		}

		compare = c3.getText();
		if (compare.length() != 0) {

			record[recNum][4] = c3.getText();

		}
	
		else {

			record[recNum][4] = "";
 
		}
		
		compare = c4.getText();
		if (compare.length() != 0) {

			record[recNum][5] = c4.getText();

		}

		else {

			record[recNum][5] = "";


		}

		compare = c5.getText();	
		if (compare.length() != 0) {

			record[recNum][6] = c5.getText();

		}

		else {

			record[recNum][6] = "";

		}

/*Set variable for the paint routine*/

		paintRecord = recNum;

	}

	public void searchRoll() {
		
/*Intializes local varialbe*/

		matches = 0;

/*Pulls class from GUI to search for*/

		courseText = course.getText();

/*Begins search in all the records for the class*/

		for (x = 0; x <= numberOfRecords - 1; x++) {

/*Searches all the class fields in each record for the class*/

			for (y = 2; y <= 6; y++) {

				if (courseText.equalsIgnoreCase(record[x][y])) {

/*If match is found, pulls student name and SSN and stores it to an array*/

					roll[matches][0] = record[x][0];
					roll[matches][1] = record[x][1];
					matches++;

				}

			}

		}		
		
/*Prints search results*/

		process = 6;
		repaint();

	}

	public void paint(Graphics g) {

		g.setFont(new Font("TimesRoman", Font.BOLD, 20));
		if (process == 1) {

/*Error message for no name*/

			g.drawString("You must give a name.", 200, 50);

		}

		if (process == 2) {

/*Error message for no SSN*/

			g.drawString("You must give a valid SSN.", 200, 50);

		}

		if (process == 3) {

/*Error message for no classes entered*/

			g.drawString("You must enter at least one class.", 200, 50);

		}

		if (process == 4) {

/*Confrimation message for entering in classes*/

			g.drawString("Thank you " + record[numberOfRecords - 1][0], 200, 50);
			g.drawString("You are registered for:", 200, 80);
			g.drawString(record[paintRecord][2], 200, 100);

/*Checks class fields to make sure they are not empty before they print out*/

			if (record[paintRecord][3] != null) {

				g.drawString(record[paintRecord][3], 200, 120);

				if (record[paintRecord][4] != null) {

					g.drawString(record[paintRecord][4], 200, 140);

					if (record[paintRecord][5] != null) {

						g.drawString(record[paintRecord][5], 200, 160);

						if (record[paintRecord][6] != null) {

							g.drawString(record[paintRecord][6], 200, 180);

						}

					}

				}

			}

		}

		if (process == 5) {

/*Welcome screen*/

			g.drawString("Enter your name, SSN, ", 250, 200);
			g.drawString("and your class choices.", 250, 220);

		}

		if (process == 6) {

/*List of students in a class*/

			g.drawString("Students in class " + courseText + " :", 250, 60);
			for (x = 0; x <= matches - 1; x++) {

				g.drawString(roll[x][0] + "     " + roll[x][1], 250, (100 + (x * 20)));

			}

		}

	}

/*Subroutine for pulling intergers from textfields*/

	int intFromTextField(TextField tf) {

		String TextforConversion;
		int IntegerReturned;
		TextforConversion = tf.getText();

		try {
			IntegerReturned = Integer.parseInt(TextforConversion);
		}

		catch (Exception e) {
			IntegerReturned = 0;
		}

		return IntegerReturned;

	}

}