RTP = (Total Amount Returned to Players / Total Amount Wagered) × 100

Target ranges by game type:
- Casual/Social: 95-98% RTP (player-friendly)
- Balanced: 92-95% RTP (sustainable)  
- High-stakes: 88-92% RTP (house-favorable)

House Edge = 100% - RTP

Example:
RTP = 96% → House Edge = 4%
For every 100 coins wagered, house keeps ~4 coins long-term

interface BetCalculation {
  level: 'fold' | 'call' | 'all_in';
  amount: number;
  multiplier: number;
  potentialWin: number;
  expectedValue: number;
}

function calculateBet(
  coins: number, 
  level: BetLevel, 
  potSuccess: number,
  multiplier: number
): BetCalculation {
  const amounts = {
    fold: 0,
    call: Math.floor(coins * 0.1),
    all_in: coins
  };
  
  const amount = amounts[level];
  const potentialWin = Math.floor(amount * multiplier);
  const expectedValue = (potSuccess * potentialWin) - ((1 - potSuccess) * amount);
  
  return { level, amount, multiplier, potentialWin, expectedValue };
}

Multiplier = (1 / Win_Probability) × RTP_Target

Example for 40% win rate at 94% RTP:
Multiplier = (1 / 0.40) × 0.94 = 2.35x

Payout table:
- Call bet (10%): Win = 2.35x stake
- All-in: Win = 2.35x stake (same multiplier, higher stakes)

| Outcome | Probability | Payout | Contribution to RTP |
|---------|-------------|--------|---------------------|
| Win     | P%          | Mx     | P × M              |
| Push    | Q%          | 1x     | Q × 1              |
| Lose    | R%          | 0x     | 0                  |
| TOTAL   | 100%        | -      | RTP%               |

| Pot State | Probability | Payout | RTP Contribution |
|-----------|-------------|--------|------------------|
| ≥80%      | 15%         | 3.0x   | 45%             |
| 50-79%    | 35%         | 1.8x   | 63%             |
| 20-49%    | 30%         | 0.5x   | 15%             |
| <20%      | 20%         | 0x     | 0%              |
| TOTAL     | 100%        | -      | 123% → adjust   |

Adjustment needed: Scale payouts by 0.94/1.23 = 0.764
New payouts: 2.29x, 1.38x, 0.38x, 0x → RTP ≈ 94%

Target metrics per session:
- Average session: 10-15 bets
- Net outcome: -5% to +20% of starting bankroll
- "Near miss" rate: 15-20% (engagement driver)
- Big win frequency: 1 in 20-50 sessions

function simulateSession(
  startingCoins: number,
  betsPerSession: number,
  betSize: number,
  winProb: number,
  winMultiplier: number
): SimulationResult {
  let coins = startingCoins;
  let wins = 0;
  
  for (let i = 0; i < betsPerSession; i++) {
    coins -= betSize;
    if (Math.random() < winProb) {
      coins += betSize * winMultiplier;
      wins++;
    }
  }
  
  return {
    finalCoins: coins,
    netChange: coins - startingCoins,
    winRate: wins / betsPerSession,
    rtp: (coins + (betsPerSession * betSize) - startingCoins) / (betsPerSession * betSize)
  };
}

// Run 10,000 sessions to validate RTP converges to target