public class CMDParser {
    //set soSocTimeout
    //Receive

    static boolean smode;       //sender mode
    static boolean rmode;       //receiver mode
    static String clientfile;   //-i [filename]; file to be sent from client to host
    static String hostfile;     //-o [filename]; file to be sent from host to sender
    static boolean ifile;       //ifile can only be active if in sender mode
    static boolean ofile;       //ofile can only be active if in receiver mode
    static String targethost;   //-T [hostname]; connecting host for receiver
    static int windowsize;      //-w [number]; size of window
    static int timeout = 200;   //-t [milliseconds]; timeout in milliseconds
    static int payload = 512;   //-m [bytes]; size of payload in bytes


    public static void main(String[] args)
    {
        try
        {
            validateArgs(args);
            if ((!smode) || (!rmode))
                {
                System.out.println("Arguments Successfully Parsed!");
                if (smode)
                {
                    Sender s = new Sender(clientfile, targethost, windowsize, timeout, payload);
                    s.run();
                }
                else
                {
                    Receiver r = new Receiver(hostfile, targethost, windowsize, timeout, payload);
                    r.run();
                }
            }
            else
            {
                System.out.println("No mode specified!");
            }
            System.exit(0);
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
    }

    private static void validateArgs(String[] args)
    {
        if (args.length == 0)
        {
            System.out.println("No arguments specified");
            System.exit(0);
        }
        else if ((args.length != 5) && (args.length != 7) && (args.length != 9) && (args.length != 11))
        {
            System.out.println("Invalid arguments");
            System.exit(0);
        }
        else
        {
            for (int i = 0; i < args.length; i++)
            {
                if ( !(args[i].equals("-s")) && !(args[i].equals("-r")) && !(args[i].equals("-i")) && !(args[i].equals("-o")) && !(args[i].equals("-T")) && !(args[i].equals("-w")) && !(args[i].equals("-t")) && !(args[i].equals("-m")) ){
                    System.out.println("No valid argument specified!");
                    System.exit(0);
                }
                if (args[i].equals("-s")) {
                    if (!rmode) { smode = true; System.out.println("Sender mode activated.");} else { System.out.println("Receiver mode already declared!"); System.exit(0); } //sender
                }else if (args[i].equals("-r")){
                    if (!smode) { rmode = true; System.out.println("Receiver mode activated.");} else { System.out.println("Sender mode already declared!"); System.exit(0); } //receiver
                }else{
                    if (args[i].equals("-i")){
                        if ((!ofile) && (!rmode)) { clientfile = new String(args[i+1]); System.out.println("Client file is " + clientfile);} else { System.out.println("'-i' is not compatible with receiver mode!"); System.exit(0); }
                    }else if (args[i].equals("-o")){
                        if ((!ifile) && (!smode)) { hostfile = new String(args[i+1]); System.out.println("Host file is " + hostfile);} else { System.out.println("'-o' is not compatible with sender mode!"); System.exit(0); }
                    }else if (args[i].equals("-T")){
                        targethost = args[i+1];
                        System.out.println("Target host is " + targethost);
                    }else if (args[i].equals("-w")){
                        windowsize = Integer.parseInt(args[i+1]);
                        System.out.println("Window size is " + windowsize);
                    }else if (args[i].equals("-t")){
                        timeout = Integer.parseInt(args[i+1]);
                        System.out.println("Timeout value is " + timeout + " milliseconds");
                    }else if (args[i].equals("-m")){
                        payload = Integer.parseInt(args[i+1]);
                        System.out.println("Payload size is " + payload + "bytes");
                    }
                    i++;
                }
            }
        }
    }
}