import { v4 as uuidv4 } from 'uuid';

// `uuid` relies on a `crypto.getRandomValues` implementation, which React
// Native does not provide out of the box. `react-native-get-random-values` is
// the canonical polyfill, but it's an optional peer dependency: consumers may
// already polyfill `crypto.getRandomValues` themselves (e.g. via
// react-native-quick-crypto), so we don't want to force it on everyone.
try {
  require('react-native-get-random-values');
} catch {
  // No-op: a `crypto.getRandomValues` polyfill may already be installed globally.
}

export const getUUID = (): string => {
  try {
    return uuidv4().toString();
  } catch {
    throw new Error(
      "@segment/analytics-react-native requires a 'crypto.getRandomValues' " +
        "polyfill, which doesn't appear to be installed. Install " +
        "'react-native-get-random-values' and import before " +
        'initializing the analytics client.'
    );
  }
};