public class BankDatabase
{
    private Account[] accounts;

    public BankDatabase()
    {
        accounts = new Account[2];
        accounts[0] = new Account(12345, 54321, 1000.0, 1200.0);
        accounts[1] = new Account(98765, 56789, 200.0, 200.0);
    }

    private Account getAccount(int accountNumber)
    {
        for(Account currentAccount : accounts)
        {
            if(currentAccount.getAccountNumber() == accountNumber)
                return currentAccount;
        }
        return null;
    }

    public boolean authenticateUser(int userAccountNumber, int userPIN)
    {
        Account userAccount = getAccount(userAccountNumber);

        if(userAccount != null)
            return userAccount.validatePIN(userPIN);
        else
            return false;
    }

    public double getAvailableBalance(int userAccountNumber)
    {
        return getAccount(userAccountNumber).getAvailableBalance();
    }

    public double getTotalBalance(int userAccountNumber)
    {
        return getAccount(userAccountNumber).getTotalBalance();
    }

    public void credit(int userAccountNumber, double amount)
    {
        getAccount(userAccountNumber).credit(amount);
    }

    public void debit(int userAccountNumber, double amount)
    {
        getAccount(userAccountNumber).debit(amount);
    }
}