akapur99 / card-game-blackjack

Simple Command Line Black Jack Game (Python)

DESIGN: Blackjack

Abhimanyu Kapur, 2019

Instructions

To run: python ./blackjack/__main__.py

To install as package ./install.sh Though not really much need for this

Rationale for Choice of Tools / Data Structures

Language: Python I chose Python over other languages such as C, Java, JS, etc. as my goal was to create a simple, small and quick card game. The standard library in Python is quite useful and abstracts away the implementation of basic data structures and methods - I didn't want to use external libraries so this worked out well.

Data Structures I didn't use any complex data structures such as trees, dictionaries (hashtables) or searching/sorting algorithms as I didn't think any were needed in this project (I initially implemented binary search to deal with aces and face cards but refactored my code rendering it unnecessary). I used created Person and Deck classes as to represent the player/dealer and the deck of cards. This helped me simplify the code and make it more intuitive. I use lists to represent the card decks and hands. I considered using a dictionary due to improved time efficiency of indexing - however given that the size of the card deck would be a max of 52 and hands would rarely exceed 9, I didn't think it was necessary. Also I needed to 'randomly' shuffle the card deck, which was easy with a list.

Note about Game Design: I've never played Black Jack before, and based most of the game instructions on an article. I've realised a little late that splitting is a part of the game hence I wasn't able to include it. Also, I made the game single player, although given the design of the program, it would be pretty simple to allow multiple players.

Modules

__main__ : Driver code which runs the game

helpers : Contain useful helper functions

deck : Contains deck class

person : Contains Person class

Pseudo code for logic/algorithmic flow

The blackjack game will run as follows:

1. Execute from CLI or in IDE
2. In __main__.py, main() is called
3. Print instructions and take user input for initial wager and name
4. Initialize objects for player, dealer, card deck
5. call play() function
6. In play(), Initialize necessary variables for game
7. Start 'playing' within a loop with optional exit condition allowing replayability
8. Deal cards to player and dealer (if possible)
9. Show Dealer's 'hole' cards
10. Evaluate player and dealer's hands
11. if no one has BlackJack or has gone bust, let the player choose their next move, validate it and continue
12. If BlackJack or Bust, add/deduct from winnings and ask player if they want to replay
13. If yes, ask to change wager and restart by re-initializing game variables
14. If no, condition to exit loop is met, exit loop and reach end of function
15. Control passes back to main()
16. Check and save high_scores (if in top 6)
17. Print high score board
18. The game completes and exit.

Testing plan

Integration testing. Assembled the game and test it as a whole. In each case, examined the output carefully to be sure it has the correct results.

Edge cases included wager out of range, incorrect moves given, deleting high_scores.txt before running, incorrect answer to yes/no queries.

Module testing. Tested each function independently.