Programmierprojekt/documents/docs/game-engine/game-engine-control.md

Game Engine Control

• GameController
• How the Server interacts with the GameController
  • Starting a Game
  • Preflop Actions
  • Flop
  • Turn
  • River
  • Showdown
• Server Outputs
  • Get full game state
  • Get community cards
  • Get player hole cards

GameController

The GameController acts as the main entry point for controlling the poker game logic from the server.

The server does not manipulate the game state directly. Instead, it interacts exclusively with the GameController, which internally coordinates:

• the GameEngine
• the GameState
• the RuleEngine
• the RoundManager
• the TurnManager

How the Server interacts with the GameController

The server calls methods on the GameController to control the game.

Starting a Game

GameController game = new GameController(engine);

game.addPlayer(PlayerId.of("Julian"), 20000);
game.addPlayer(PlayerId.of("Mathis"), 20000);
game.addPlayer(PlayerId.of("Jona"), 20000);
game.addPlayer(PlayerId.of("Lars"), 20000);

game.startGame();

Steps performed:

1. Create a GameController instance.
2. Add players with their starting chip stacks.
3. Start the game.

When startGame() is called:

• the deck is prepared
• hole cards are dealt
• the game phase switches to PREFLOP

Preflop Actions

During the preflop phase, players perform actions.

game.playerCall(PlayerId.of("Julian"));
game.playerFold(PlayerId.of("Mathis"));
game.playerCall(PlayerId.of("Jona"));
game.playerRaise(PlayerId.of("Lars"), 1200);

Supported actions include:

• playerCall(playerId)
• playerFold(playerId)
• playerRaise(playerId, amount)

The GameController passes these actions on to the GameEngine, which validates them using the RuleEngine.

Flop

Once the preflop betting round is completed, the server can deal the flop.

game.dealFlop();

This will:

• draw 3 community cards
• add them to the board
• update the game phase

Turn

game.dealTurn();

This deals the fourth community card.

River

game.dealRiver();

This deals the fifth and final community card and starts the final betting round.

Showdown

After the final betting round, the server can determine the winner.

String winner = game.showdown();

This will:

• evaluate the hands of all remaining players
• determine the best poker hand
• award the pot to the winner
• end the current hand

Example:

Winner: Julian
Pot: 3200

During the showdown, each remaining player's hand is evaluated using their:

• two hole cards
• five community cards

The best possible 5-card poker hand wins the pot.

Server Outputs

The server can query the current game state at any time.

Get full game state

GameState state = game.getState();

Returns the complete game state.

The state includes information such as:

• players
• chip stacks
• pot
• current game phase
• deck state

Get community cards

List<Card> board = game.getCommunityCards();

Returns the community cards currently on the board.

The number of cards depends on the game phase:

• Flop -> 3 cards
• Turn -> 4 cards
• River -> 5 cards

Example:

[NINE of DIAMONDS, TEN of SPADES, JACK of CLUBS]

Get player hole cards

Map<PlayerId, List<Card>> cards = game.getPlayerCards();

Returns a mapping of player IDs to their hole cards.

Each player receives two private cards at the start of the hand.

playerId -> [Card, Card]

Example:

Mathis -> [NINE of DIAMONDS, TEN of SPADES]
Lars   -> [JACK of SPADES, TWO of HEARTS]
Jona   -> [SEVEN of DIAMONDS, TWO of DIAMONDS]
Julian -> [NINE of HEARTS, FIVE of DIAMONDS]