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package os.assignment;

import java.nio.file.InvalidPathException;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.Scanner;
import java.lang.NullPointerException;
/**
 *
 * @author DELL
 */
public class Parser {

    String[] args=new String[2];
    String cmd;

    public boolean parse(String input) throws NullPointerException
    {
        Scanner In = new Scanner(System.in);
        input = In.nextLine();
        ArrayList<String> Command_by2par = new ArrayList<String>();
        ArrayList<String> Command_by1par = new ArrayList<String>();
        ArrayList<String> Command_nopar = new ArrayList<String>();
        Command_by2par.add("$cp");
        Command_by2par.add("$mv");
        Command_by1par.add("$cat");
        Command_by1par.add("$more");
        Command_by1par.add("$mkdir");
        Command_by1par.add("$rmdir");
        Command_by1par.add("$rm");
        Command_by1par.add("$cd");
        Command_nopar.add("$Is");
        Command_nopar.add("$date");
        Command_nopar.add("$pwd");
        Command_nopar.add("$clear");
        Command_nopar.add("$args");
        Command_nopar.add("$help");
        String[] token = input.split(" ");
        int choice = 3;
        for (int i = 0; i < 2; i++)
            if (Command_by2par.get(i).equals(token[0])) {
                choice = 2;
                break;
            }
        for (int i = 0; i < 6; i++)
            if (Command_by1par.get(i).equals(token[0])) {
                choice = 1;
                break;
            }
        for (int i = 0; i < 6; i++)
            if (Command_nopar.get(i).equals(token[0])) {
                choice = 0;
                break;
            }
        if (choice==3)
                System.out.println("Yoy Write Wrong Command");


        if (choice == 1 && token[1] != null) {
            if(ValidPath(token[1]))
                    cmd=token[0];
                    args[0]=token[1];
        }
        else if (token[1] == null) {
            System.out.println(token[0] + " command should have one parameter");
        }
            if (choice == 2 && token[1] != null && token[2] != null) {
                if(ValidPath(token[1]))
                    cmd=token[0];
                    args[0]=token[1];
                    args[1]=token[2];
        }
            else if (token[1] == null || token[2] == null) {
                System.out.println(token[0] + " command should have two parameter");
        }
        if (choice == 0 && token[1] == null && token[2] == null) {
                    cmd=token[0];
        }
        else if (token[1] == null) {
            System.out.println(token[0] + " command should not have parameter");
        }
        System.out.println(cmd+args[0]+args[1]);
        return false;
    }

    public String getCmd() {
        return cmd;
    }

    public String[] getArguments() {
        return args;
    }
    public static boolean ValidPath(String path) {
    try {
        Paths.get(path);
    } catch (InvalidPathException | NullPointerException ex) {
        return false;
    }
    return true;
}
}