metro.config.js

const { getDefaultConfig } = require('@expo/metro-config')
const path = require('path')

// Storybook provides a helper to patch Metro config for React Native usage.
// It prevents bundling server/web-only pieces into the RN app.
let config = getDefaultConfig(__dirname)
config.resolver = config.resolver || {}
config.resolver.extraNodeModules = config.resolver.extraNodeModules || {}

// map 'storybook' to the installed @storybook folder so internal imports can resolve
config.resolver.extraNodeModules['storybook'] = path.resolve(
  __dirname,
  'node_modules',
  '@storybook',
)
// map some Node built-ins to React Native friendly shims to avoid bundling errors
config.resolver.extraNodeModules['tty'] = path.resolve(
  __dirname,
  'rn-node-shims',
  'tty.js',
)
config.resolver.extraNodeModules['fs'] = path.resolve(
  __dirname,
  'rn-node-shims',
  'fs.js',
)
config.resolver.extraNodeModules['path'] = path.resolve(
  __dirname,
  'rn-node-shims',
  'path.js',
)
config.resolver.extraNodeModules['os'] = path.resolve(
  __dirname,
  'rn-node-shims',
  'os.js',
)

// Ensure Metro resolves .cjs files (storybook ships some CJS files)
config.resolver.sourceExts = [
  ...Array.from(new Set([...(config.resolver.sourceExts || []), 'cjs'])),
  '.md',
]

try {
  // prefer withStorybookConfig/withStorybook if available
  // biome-ignore lint/correctness/noUnusedVariables: does not matter here
  const { withStorybook, withStorybookConfig } =
    require('@storybook/react-native/metro/withStorybook') || {}
  // Some versions export the helpers directly from paths
  const withSB =
    require('@storybook/react-native/metro/withStorybook') ||
    require('@storybook/react-native/metro/withStorybookConfig')
  if (typeof withSB === 'function') {
    config = withSB(config)
  }
} catch (e) {
  // If the helper isn't available, fall back to the patched config above.
  // We still have node shims and extra ext resolution applied.
  console.warn(
    'withStorybook helper not applied (ok if not installed):',
    e?.message || e,
  )
}

module.exports = config