// ATMSavingsAccount.java
// Solution to Short Assignment 11 by THC.

// Defines a class of ATM savings account.
// The first two withdrawals are free, and then they cost $1.50 in each period.
// Deposits are always free.

public class ATMSavingsAccount extends SavingsAccount {
  private static final int FREE_WITHDRAWALS = 2;
  private static final double TRANSACTION_FEE = 1.50;
  private int withdrawals;

  // Constructor that sets rate.
  public ATMSavingsAccount(double rate) {
    super(rate);
    withdrawals = 0;
  }

  // Constructor that sets rate and initial balance.
  public ATMSavingsAccount(double rate, double initialAmount) {
    super(rate, initialAmount);
    withdrawals = 0;
  }

  // Withdraw amount from account, but count as a withdrawal.
  public void withdraw(double amount) {
    super.withdraw(amount);
    withdrawals++;
  }

  // Add the periodic interest, but then subtract withdrawal fees.
  public void addPeriodicInterest() {
    super.addPeriodicInterest();
    if (withdrawals > FREE_WITHDRAWALS)
      super.withdraw(TRANSACTION_FEE * (withdrawals - FREE_WITHDRAWALS));
    withdrawals = 0;
  }
}