using System;
using System.Collections.Generic;

namespace Server.Remote
{
    public class Accounts : MarshalByRefObject, IAccounts
    {
        private List<User> list;

        public Accounts()
        {
            list = new List<User>();
        }

        /** Login
         *  Check if there's an User with the same username/password combo in the list
         *  If so, return it's ID, otherwise, return -1
         */
        public int Login(String username, String password)
        {
            foreach (User u in list)
            {
                if (u.GetUsername() == username && u.GetPassword() == password)
                {
                    Console.WriteLine("Sucessfull login attempt by: " + username);
                    return u.GetID();
                }
            }

            Console.WriteLine("Failed login attempt to account: " + username);
            return -1;
        }

        /** Register
         *  Check if there's an user with the same username in the database
         *  if not, create a new one and assign it an ID (List Count Works) and return true
         *  return false if creation failed
         */
        public Boolean Register(String username, String password)
        {
            foreach (User u in list)
            {
                if (u.GetUsername() == username)
                {
                    Console.WriteLine("Registration failed, existing user: " + username);
                    return false;
                }
            }

            Console.WriteLine("Registered a new user: " + username);
            list.Add(new User(username, password, list.Count));
            return true;
        }

        public double GetUserBalance(int user_id)
        {
            foreach (User u in list)
            {
                if (u.GetID() == user_id)
                {
                    return u.GetBalance();
                }
            }
            return 0.0;
        }
    }

    /** User Class
     *  Simple structure containing an user's information
     */
    class User
    {
        private String username, password;
        private int id;
        private double balance = 0;

        public User(String _username, String _password, int _id)
        {
            username = _username;
            password = _password;
            id = _id;
        }

        public String GetUsername()
        {
            return username;
        }

        public String GetPassword()
        {
            return password;
        }

        public int GetID()
        {
            return id;
        }

        public double GetBalance()
        {
            return balance;
        }

        public double SetBalance(double delta)
        {
            balance += delta;
            return balance;
        }
    }
}












using System;
using System.Collections.Generic;

namespace Server.Remote
{
    class TransactionCenter
    {
        private List<TransactionItem> queue_buy;
        private List<TransactionItem> queue_sell;

        public TransactionCenter()
        {
            queue_buy  = new List<TransactionItem>();
            queue_sell = new List<TransactionItem>();
        }
    }

    class TransactionItem
    {
        private int user_id;
        private double amount, price;

        public TransactionItem(int _user_id, double _amount, double _price)
        {
            user_id = _user_id;
            amount = _amount;
            price = _price;
        }
    }
}