Authors: Pedro & Camilla

Our client is a financial institution that wants to allow its customers to withdraw funds from their accounts using an Automatic Teller Machine (ATM). They have turned to us for a prototype of a system with limited functionality. Our job is to write a simple Ruby program that can be run in the Interactive Ruby Shell (IRB).

#User stories

As a bank
In order to allow my customers to withdraw funds
I need to have an ATM available

As a bank
In order to allow my customers to withraw funds
My ATM needs to have funds available

As a User
In order to interact with the ATM
I need to have an active account

As a User
In order to interact with the ATM
I need to have an account PIN

As a User
In order to interact with the ATM
I need to have an account within the expiry date

As a User
In order to withdraw funds
I need to have balance in my account

As a User       
In order to make an withdrawal      
The ATM needs to have funds

As a User
In order have balance in my account
I need to be able to make a deposit

As a User
In order to make a deposit
I need to have available cash

To interact with the ATM program open IRB or Pry and follow these steps:

# Load program in Pry or IRB. 
load './lib/atm.rb'

# Create an ATM to interact with.
newATM = Atm.new

This will create and ATM instance with 1000$ available in

• 25 bills of 20$,
• 30 bills of 10$, and
• 40 bills of 5$.

# Create a named ATM user.
newPerson = Person.new(name: 'Alfred')

# Give the user an a bank account.
newPerson.create_account

The banc account will:

• be set to active,
• get a 4 digit PIN,
• expires in 5 years, and
• have 0 in balance.

Good news! Our user just received his paycheck! His boss kindly enough rewarded him with 2000$ for his work. This will add 2000 bucks to his pocket.

# Add money to person.
newPerson.increase_cash(amount: 2000)

Now let's put all this cash in our account because, let's face it, streets ain't safe. This made our account balance to go up to 2000$, and, obviously, our cash to 0.

# Deposit money on bank account.
newPerson.deposit(2000)

It's good to have our money safe in our account, but we also need some pocket money. So let's withdraw some walk around cash. 👍

# widraw arguments: (Amount to withdraw, PIN, ATM).
newPerson.withdraw(amount:25, pin:9863, atm: newATM)

When the withdrawal is done, you'll receive a receipt and you can see the specific bills you received

At any time we can all out our instances

newATM

newPerson

And we can see how many bills and amount our ATM still has, and we can see how much cash and ballance our person has

#The Sad Path

• You won't be able to create a Person without a name
• You won't be able to make a deposit without cash available
• You won't be able to make a withrawal without a valid account, with a PIN and expiry date
• You won't be able to make a withdrawal if there is no ATM
• You won't be able to make a withdrawal if you don't have an account
• You won't be able to make a withdrawal if you don't have enough balance
• You won't be able to make a withdrawal if the ATM doesn't have enough funds
• You won't be able to make a withdrawal if you request an amount that is not divisable by 5

• Make sure it's set up
• Make sure code formatting and output is readable

Version Control

• Gitignore
• Commit
• Create Remote Repository

ATM Challenge Requirements/Checklist

• An ATM machine can hold up to $1000 Withdrawal can be cleared only if:

• The ATM holds enough funds

• The amount is divisible by 5

• The person attempting the withdrawal provides a valid ATM card

• Valid pin and expire date

• Card status must be active (Not report stolen or lost)

• The person attempting the withdrawal has sufficient funds on his account

• There are only $5, $10 and $20 bills in the ATM. Withdrawals for amounts not divisible by 5 must be rejected.

• Upon a successful withdrawal the system should return a receipt with information about the date, amount and bills that was dispatched. (The receipt should be presented in the form of a Hash.

• When a withdrawal is done, the number of bills inside the ATM must decrease

• A deposit should only be possible if a person has cash available