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

//The listproc command is a command that lists all of the processes that are being
//executed by the user issuing the command
//Listproc displays the name and the handle for the command
//This command accepts arguments to list the processes of all users (-a)

public class listproc extends VMachine
{

    public listproc()
    {
    }
    
    public void run()
    {
        
        try
        {
            int proccount = 0;
            User tuser;
            
		//if there are no args then do the default
		//display the processes running for the user
            if(args.length == 0)
            {
                sysapi.Write(OUT,"Processes owned by -" + owner + "-\n");
                
		//for each process write the process name and handle ID
                proccount = sysapi.findUser(owner).getCount();
                for(int i = 0; i < proccount; i++)
                {
                    sysapi.Write(OUT,sysapi.findUser(owner).get(i).getID() + "\n");
                }
            }
		//if the argument is -a then, display the processes owned all users
            else if(args[0].toLowerCase().compareTo("-a")==0)
            {
			//loop for each user 
	          for(int i=0; i < sysapi.getUserCount(); i++)
                {
			//get the user name
                    tuser = sysapi.getUser(i);
                    sysapi.Write(OUT,"\nProcesses owned by -" + tuser.getName() + "-\n");
                    
                    //Dangerous because Count may decrease between calls
                    proccount = tuser.getCount();
			//loop for each of the users processes
                    for(int x = 0; x < proccount; x++)
                    {
				//print process name and handle ID
                        sysapi.Write(OUT,tuser.get(x).getID() + "\n");
                    }
                }
            }
            
            
            
        }
        catch (Exception err)
        {
		//some type of error happened
            System.out.println("ListProc threw an Exception.");
        }
        sysapi.Exit(vmh,owner);
    }
    
}