// Unique ID generation utilities

import { randomBytes } from 'crypto';

const BASE62_CHARS = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';

/**
 * Generate a random base62 string of specified length.
 * Uses cryptographically secure random bytes.
 */
export function generateSessionId(length: number = 6): string {
  const bytes = randomBytes(length);
  let result = '';

  for (let i = 0; i < length; i++) {
    result += BASE62_CHARS[bytes[i] % BASE62_CHARS.length];
  }

  return result;
}

/**
 * Generate a UUID v4 for request IDs.
 */
export function generateRequestId(): string {
  return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, (c) => {
    const r = Math.random() * 16 | 0;
    const v = c === 'x' ? r : (r & 0x3 | 0x8);
    return v.toString(16);
  });
}