# betting-round-flow Specification

## Purpose
TBD - created by archiving change fix-texas-holdem-rules. Update Purpose after archive.
## Requirements
### Requirement: Check action does not modify player chip count or bet contribution
When a player checks, the system SHALL only mark the player as having matched the current bet level without deducting chips or modifying their `currentBet` value.

#### Scenario: Check with zero current bet
- **WHEN** the current bet is 0 and Player A checks
- **THEN** Player A's `betMatched` becomes true, `currentBet` remains unchanged, and chip count remains unchanged

#### Scenario: Check after matching previous bet
- **WHEN** Player A has already called a bet of 100 (currentBet = 100) and the next player checks (no raise occurred)
- **THEN** Player A's state remains unchanged except `betMatched` is set to true

### Requirement: Betting round completes when action returns to last aggressor
The system SHALL end a betting round when all active players have matched the current bet and action returns to the position of the last player who raised or opened betting.

#### Scenario: Pre-flop BB option (no raises)
- **WHEN** SB posts 10, BB posts 20, and all players check around back to BB
- **THEN** BB may check without posting additional chips, and the betting round completes

#### Scenario: Raise requires action to return to raiser
- **WHEN** Player A raises to 100, Players B and C call, and Player D checks
- **THEN** the round does not complete until Player A either checks or faces no further raises

### Requirement: All-in players are excluded from betting round completion check
When determining if a betting round is complete, the system SHALL only consider active (non-all-in) players for the "all matched" condition.

#### Scenario: Active player skipped by all-in completion bug
- **WHEN** Player A bets 100, Player B goes all-in for 50, and Player C has not yet acted
- **THEN** the betting round does NOT complete; Player C must act before the round advances

#### Scenario: Single active player ends round
- **WHEN** all players except one have folded or gone all-in
- **THEN** the betting round completes immediately and the game proceeds to the next stage

### Requirement: Turn advancement skips non-active players correctly
The system SHALL advance turns to the next player with `status === 'active'`, skipping folded and all-in players.

#### Scenario: Folded player is skipped
- **WHEN** Player A folds and it's their turn position
- **THEN** the turn advances to the next active player clockwise from Player A

#### Scenario: All-in player is skipped during betting
- **WHEN** Player B goes all-in during a betting round
- **THEN** subsequent turns skip Player B and advance to the next active player