import java.io.*;
import java.lang.*;
import java.util.*;

public class EventGenerator
{
	int NumberOfEvents;
	int NumberOfUsers;
	int event_id;
	char event_type;
	int sender_id;
	int receiver_id;
	int time;
	int priority;
	String message;
	Random R;

	public EventGenerator(int EventNumber, int UserNumber)
	{
		NumberOfEvents = EventNumber;
		NumberOfUsers = UserNumber;
		R = new Random();
		event_id = 0;
		event_type = 'S';
		sender_id = -1;
		receiver_id = -1;
		time = -1;
		priority = -1;
		message = "Initially empty";
	}

	public void output()
	{
		try{
			FileOutputStream printToFile = new FileOutputStream("events.txt");
			PrintStream out = new PrintStream(printToFile);

			out.print("event_id" + "   ");
			out.print("event_type" + "     ");
			out.print("time" + "      ");
			out.print("receiver_id" + "   ");
			out.print("sender_id" + "    ");	
			out.print("priority" + "        ");
			out.println("message");

		for (int i = 0; i < NumberOfEvents; i++)
		{
			event_id++; 	// increase event_id for each event
			time = (int)(R.nextDouble() * 1000);	// set randome time
			receiver_id = 10 * ((int)(R.nextDouble() * NumberOfUsers) + 1); // ended with 0

			if (R.nextDouble() > 0.7)
			{
				event_type = 'R';	// 30% chance to be a receiving event
				out.print(event_id + " " + '\t' + "    ");
				out.print(event_type + "  " + '\t' + "    ");
				out.print(time + "  " + '\t' + "    ");
				out.println(receiver_id + "  " + '\t');
		}
		else 
		{
			event_type = 'S';	//	70% chance to be a sending event
			sender_id = 10 * ((int)(R.nextDouble() * NumberOfUsers) + 1);
			if (R.nextDouble() > 0.45)	
				priority = 1;	// 55% chance to be NORMAL
			else if (R.nextDouble() > 0.15)
					priority = 2;	// 30% chance to be RUSH
			else priority = 3;	// 15% chance to be TOP

			switch((int)(R.nextDouble() * 10))
			{
				case 0: message = "We like CSE373";
						break;
				case 1: message = "CSE373 is interesting";
						break;
				case 2: message = "Assignments are so easy";
						break;
				case 3: message = "I spend little time on projects";
						break;
				case 4: message = "Midterm is coming soon";
						break;
				case 5: message = "I wish to get a high grade";
						break;
				case 6: message = "I am using Java";
						break;
				case 7: message = "Is C++ more efficient?";
						break;
				case 8: message = "We are great programmers";
						break;
				case 9: message = "Always enjoying programming!";
			}	// end switch
	
			out.print(event_id + " " + '\t' + "    ");
			out.print(event_type + "  " + '\t' + "    ");
			out.print(time + "  " + '\t' + "    ");
			out.print(receiver_id + "  " + '\t' + "    ");
			out.print(sender_id + "  " + '\t' + "      ");	
			out.print(priority + "  " + '\t' + "    ");
			out.println(message);
		}	// end else
	}	// end for
	printToFile.close();
	out.close();
	}	// end try
	catch (IOException e)
		{
			System.out.println("Error in writing events.txt"); 
		}
	return;	// end output
	}	
    
	public static void main(String[] args)
	{
		try
		{
			EventGenerator event = new EventGenerator(Integer.parseInt(args[0]), Integer.parseInt(args[1]));
			event.output();
		}
		catch (ArrayIndexOutOfBoundsException e)
		{
			System.out.println("Must specify the number of events and users ");
			System.out.println("Usage: java EventGenerator EventNumber UserNumber");
		}
		return;
	}
}	// end EventGenerator