package bank;

import java.util.HashMap;

public class Bank {
    private static Bank bank;
    HashMap<String, Account> Accounts = new HashMap<String, Account>();
    int accountNumber;

    private Bank() {}

    public static Bank getBank() {
        if(bank == null) bank = new Bank();
        return bank;
    }

    public Account createAccount() {
        Accounts.put(++accountNumber + "", new Account(accountNumber + ""));
        return Accounts.get(accountNumber + "");
    }

    public Account lookupAccount(String number) {
        return Accounts.get(number);
    }

    public int getBalance(String accountNo) throws AccountException {
        if (!Accounts.containsKey(accountNo)) throw new AccountException("Account " + accountNo + " doesn't exist");
        else return Accounts.get(accountNo).getBalance();
    }

    public void deposit(String accountNo, int howMuch) throws AccountException {
        if (!Accounts.containsKey(accountNo)) throw new AccountException("Account " + accountNo + " doesn't exist");
        else Accounts.get(accountNo).deposit(howMuch);
    }

    public void withdraw(String accountNo, int howMuch) throws AccountException {
        if (!Accounts.containsKey(accountNo)) throw new AccountException("Account " + accountNo + " doesn't exist");
        else Accounts.get(accountNo).withdraw(howMuch);
    }

    public void transfer(String sourceAccount, int howMuch, String targetAccount) throws AccountException {
        if (!Accounts.containsKey(sourceAccount)) throw new AccountException("Account " + sourceAccount + " doesn't exist");
        else if (!Accounts.containsKey(targetAccount)) throw new AccountException("Account " + targetAccount + " doesn't exist");
        else Accounts.get(sourceAccount).transfer(howMuch, Accounts.get(targetAccount));
    }

    public void closeAccount(String accountNo) throws AccountException {
        if (!Accounts.containsKey(accountNo)) throw new AccountException("Account " + accountNo + " doesn't exist");
        else Accounts.get(accountNo).closeAccount();
    }

}