//File:  newusr.java
//CS 471 - Operating Systems Project
//Dennis Pereira, Ely Soto, John Cavalieri

//The newusr command prompts the user for the information necessary
//to add a new user to the login file
//it will allow the new user to login in future sessions
//and it will put the user's password into the password file

import java.io.*;

public class newusr extends VMachine {
    
    /* Creates new newusr */
    public newusr() {
    }
    
    public void run() {
        
        try
        {
		//var to see if the user already exists
            int match = 0;

		//prompt user for new user name            
            sysapi.Write(OUT,"Please enter your username (No spaces): ");
		//read input
            String newusrname = sysapi.Read(IN);
		//vars used to compare password confirmation
            String password1;
            String password2;
            
            do
            {
			//password confirmation
                sysapi.Write(OUT,"Please enter your password (No spaces):");
                password1 = sysapi.Read(IN);
                sysapi.Write(OUT,"Please reenter your password: ");
                password2 = sysapi.Read(IN);
			//test that passwords match
                if(password1.compareTo(password2)==0)
                {
                    match=1;
                }
                else
                {
			//passwords don't match, loop until they do
                    sysapi.Write(OUT,"Passwords do not match.\n");
                }
            }while(match==0);  //loop until passwords match
            
		//create a password file for the user
            File passfile = new File("C:\\java\\OSVM\\sys\\pass");
            passfile.createNewFile();
		//make the file editable
            RandomAccessFile iostream = new RandomAccessFile(passfile,"rw");
            iostream.seek(iostream.length());
		//add the user and password the the file            
            iostream.writeBytes(newusrname + " " + password1 + "\n");
        }
        catch(Exception ex)
        {
		//something bad happened, croak with message
            System.out.println("newusr threw Exception: " + ex);
        }
        
        sysapi.Exit(vmh,owner);
    }
}