import dotenv from 'dotenv';

dotenv.config();

export const config = {
  port: parseInt(process.env.PORT || '3001'),
  host: process.env.HOST || 'localhost',
  nodeEnv: process.env.NODE_ENV || 'development',
  jwtSecret: process.env.JWT_SECRET || 'your-super-secret-jwt-key-change-in-production',
  corsOrigin: process.env.CORS_ORIGIN ? process.env.CORS_ORIGIN.split(',') : ['http://localhost:3000'],
  
  // Rate limiting
  rateLimits: {
    pixelsPerMinute: parseInt(process.env.RATE_LIMIT_PIXELS_PER_MINUTE || '60'),
    pixelsPerHour: parseInt(process.env.RATE_LIMIT_PIXELS_PER_HOUR || '1000'),
    cursorUpdatesPerSecond: parseInt(process.env.RATE_LIMIT_CURSOR_PER_SECOND || '10'),
  },

  // Canvas settings
  canvas: {
    maxSize: parseInt(process.env.MAX_CANVAS_SIZE || '10000'),
    defaultSize: parseInt(process.env.DEFAULT_CANVAS_SIZE || '1000'),
    chunkSize: parseInt(process.env.CHUNK_SIZE || '64'),
  },

  // Redis settings
  redis: {
    url: process.env.REDIS_URL || 'redis://localhost:6379',
    keyPrefix: process.env.REDIS_KEY_PREFIX || 'gaplace:',
  },

  // Logging
  logLevel: process.env.LOG_LEVEL || 'info',
} as const;

export function validateConfig(): void {
  const required = ['JWT_SECRET'];
  const missing = required.filter(key => !process.env[key]);
  
  if (missing.length > 0 && config.nodeEnv === 'production') {
    throw new Error(`Missing required environment variables: ${missing.join(', ')}`);
  }
}