using System;

using UserAccountNamespace; 

using ItemNamespace;

using System.Collections.Generic;

​

public class LogIn{//add new users here

    private Dictionary<string,Cashier> records;

    public LogIn(){

        records = new Dictionary<string, Cashier>();

        records.Add("Pat_T", new Cashier("Patricia Tanque","Sales","Pat_T","patricia123"));

        records.Add("Bia_T", new Cashier("Bianca Tanque","Sales","Bia_T","bianca123"));

    }

    public bool vLogIn(string uname, string pass){

        if (records.ContainsKey(uname))

            {

                Cashier c = records[uname];

                return c.validateLogin(uname, pass);

            }

        else { return false; }

    }

}

​

public class Program

{

    static Dictionary<string,Cashier> records;

    public static void Main()

    {   

        while(true){

            Console.WriteLine("User Login\n----------------");

            Console.WriteLine("Username: ");

            string u = Console.ReadLine();

            Console.WriteLine("Password: ");

            string p = Console.ReadLine();

            LogIn lg = new LogIn();

            if (lg.vLogIn(u,p)){

                bool run = true;

                while (run){

                    Console.WriteLine("\nWelcome. What do you want to do?");

                    Console.WriteLine("1 - Cashier\n2 - Logout\n3 - Exit");

                    int ans = int.Parse(Console.ReadLine());

                    switch (ans){

                        case 1:

                            items();

                            break;

                        case 2:

                            run = false;

                            Console.WriteLine("Logging out..");

                            break;

                        case 3:

                            Console.WriteLine("Exiting program...");

                            return;

                        default:

                            Console.WriteLine("Invalid input");

                            break;

                    }

                }

            }

            else {

                Console.WriteLine("No user found. Try again");

            }

            Console.WriteLine("");

        }

    }

    public static void items(){//cashier

        bool run = true;

        while(run){

            Console.WriteLine("\n----------------");

            Console.Write("Name of item: ");

            string n = Console.ReadLine();

            Console.Write("Price: ");

            double p = double.Parse(Console.ReadLine());

            Console.Write("Quantity: ");

            int q = int.Parse(Console.ReadLine());

            Console.Write("Discount (set to 0 if none): ");

            double d = double.Parse(Console.ReadLine());

            DiscountItem di = new DiscountItem(n,p,q,d);

            Console.Write("Total: "+di.getTotalPrice());

            Console.Write("\nPayment: ");

            double pay = double.Parse(Console.ReadLine());

            di.setPayment(pay);

            Console.Write("Change: "+di.getChange());

            Console.WriteLine("\n----------------");

            Console.Write("\nWill you make another transaction? (yes/no): ");

            string ans = Console.ReadLine();

            if (ans == "yes"){

                run=true;

            }

            else if (ans=="no"){

                run = false;

                Console.WriteLine("Exiting cashier...");

            }

        }

    }

}

​

namespace UserAccountNamespace{

    abstract class UserAccount{

        private string full_name;

        protected string user_name;

        protected string user_password;

        public UserAccount(string name, string uName, string password){

            this.full_name=name;

            this.user_name=uName;

            this.user_password=password;

        }

        public abstract bool validateLogin(string uName, string password);

        public string getFullName(){

            return full_name;

        }

    }

    class Cashier:UserAccount{

        private string department;

        public Cashier(string name, string department, string uName, string password):base(name,uName,password){

        this.department=department;

        }

        public override bool validateLogin(string uName, string password){

            return uName.Equals(user_name)&&password.Equals(user_password);

        }

        public string getDepartment(){

            return department;

        }

    }

}

​

namespace ItemNamespace{

    public abstract class Item{

        protected string item_name;

        protected double item_price;

        protected int item_quantity;

        private double total_price;

        public Item(string name, double price, int quantity){

            this.item_name=name;

            this.item_price=price;

            this.item_quantity=quantity;

        }

        public abstract double getTotalPrice();

        public abstract void setPayment(double amount);

    }

    public class DiscountItem:Item{

        private double item_discount;

        private double discounted_price;

        private double payment_amount;

        private double change;

        public DiscountItem(string name, double price, int quantity,  double discount): base(name,price,quantity){

            this.item_discount=discount;

        }

        public override double getTotalPrice(){

            this.discounted_price = (item_price-((item_discount/100)*item_price))*item_quantity;

            return discounted_price;

        }

        public override void setPayment(double amount){

            this.payment_amount=amount;

        }

        public double getChange(){

            return payment_amount - discounted_price;

        }

    }

}

​