Coin Flip API for Developers

import { useState } from 'react';

export function useCoinFlip() {
  const [result, setResult] = useState(null);
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState(null);

  const flip = async (count = 1) => {
    setLoading(true);
    setError(null);
    
    try {
      const url = 'https://flipacoinfree.com/api/flip';
      const options = count > 1 
        ? {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify({ count })
          }
        : { method: 'GET' };
      
      const response = await fetch(url, options);
      const data = await response.json();
      
      if (data.success) {
        setResult(data.data);
      } else {
        throw new Error('Flip failed');
      }
    } catch (err) {
      setError(err.message);
    } finally {
      setLoading(false);
    }
  };

  return { result, loading, error, flip };
}

// Usage in component
function CoinFlipApp() {
  const { result, loading, flip } = useCoinFlip();
  
  return (
    <div>
      <button onClick={() => flip()} disabled={loading}>
        {loading ? 'Flipping...' : 'Flip Coin'}
      </button>
      {result && <p>Result: {result.result}</p>}
    </div>
  );
}

class GameCoinFlip {
  constructor() {
    this.cache = [];
    this.cacheSize = 50;
  }

  async prefetchFlips() {
    const response = await fetch('https://flipacoinfree.com/api/flip', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ count: this.cacheSize })
    });
    
    const data = await response.json();
    this.cache = data.data.flips;
  }

  async getFlip() {
    // Use cached flip if available
    if (this.cache.length > 0) {
      return this.cache.shift();
    }
    
    // Refetch if cache is empty
    await this.prefetchFlips();
    return this.cache.shift();
  }

  async decideBattle(player1, player2) {
    const flip = await this.getFlip();
    return flip === 'heads' ? player1 : player2;
  }
}

// Usage
const game = new GameCoinFlip();
await game.prefetchFlips();

const winner = await game.decideBattle('Alice', 'Bob');
console.log(`Winner: ${winner}`);

class RandomnessAnalyzer {
  async testRandomness(sampleSize = 10000) {
    const response = await fetch('https://flipacoinfree.com/api/flip', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ count: sampleSize })
    });
    
    const data = await response.json();
    const { heads, tails } = data.data;
    
    // Chi-square test for fairness
    const expected = sampleSize / 2;
    const chiSquare = 
      Math.pow(heads - expected, 2) / expected +
      Math.pow(tails - expected, 2) / expected;
    
    // Critical value for 95% confidence (1 degree of freedom)
    const criticalValue = 3.841;
    const isFair = chiSquare < criticalValue;
    
    return {
      sampleSize,
      heads,
      tails,
      headsPercent: (heads / sampleSize * 100).toFixed(2),
      tailsPercent: (tails / sampleSize * 100).toFixed(2),
      chiSquare: chiSquare.toFixed(4),
      isFair,
      confidence: '95%'
    };
  }
}

// Usage
const analyzer = new RandomnessAnalyzer();
const results = await analyzer.testRandomness(10000);
console.log('Randomness Test Results:', results);
// Output: { sampleSize: 10000, heads: 5012, tails: 4988, isFair: true, ... }