const createExpoWebpackConfigAsync = require('@expo/webpack-config')
const {withAlias} = require('@expo/webpack-config/addons')
const ReactRefreshWebpackPlugin = require('@pmmmwh/react-refresh-webpack-plugin')
const {BundleAnalyzerPlugin} = require('webpack-bundle-analyzer')
const {sentryWebpackPlugin} = require('@sentry/webpack-plugin')
const {version} = require('./package.json')

const GENERATE_STATS = process.env.EXPO_PUBLIC_GENERATE_STATS === '1'
const OPEN_ANALYZER = process.env.EXPO_PUBLIC_OPEN_ANALYZER === '1'

const reactNativeWebWebviewConfiguration = {
  test: /postMock.html$/,
  use: {
    loader: 'file-loader',
    options: {
      name: '[name].[ext]',
    },
  },
}

// Walk a rule tree and wrap source-map-loader's filterSourceMappingUrl to
// drop sourcemap references matching the given path pattern. Mutates in place.
function patchSourceMapFilter(rules, pathPattern) {
  if (!rules) return
  for (const rule of rules) {
    if (!rule || typeof rule !== 'object') continue
    if (rule.oneOf) patchSourceMapFilter(rule.oneOf, pathPattern)
    if (rule.rules) patchSourceMapFilter(rule.rules, pathPattern)
    const uses = Array.isArray(rule.use) ? rule.use : rule.use ? [rule.use] : []
    for (const use of uses) {
      if (!use?.loader?.includes('source-map-loader')) continue
      const prev = use.options?.filterSourceMappingUrl
      use.options = {
        ...use.options,
        filterSourceMappingUrl(url, resourcePath) {
          if (pathPattern.test(resourcePath)) return 'remove'
          return prev ? prev(url, resourcePath) : true
        },
      }
    }
  }
}

// Walk a rule tree and add `.cjs` support everywhere the config assumes only
// `.js|.mjs|.jsx|.ts|.tsx`. Mutates in place.
function patchCjsSupport(rules) {
  if (!rules) return
  const addCjs = pattern => {
    if (!(pattern instanceof RegExp)) return pattern
    if (pattern.source.includes('cjs')) return pattern
    return new RegExp(
      pattern.source.replace(/\|tsx\)/g, '|tsx|cjs)'),
      pattern.flags,
    )
  }
  const patch = value => {
    if (value instanceof RegExp) return addCjs(value)
    if (Array.isArray(value)) return value.map(patch)
    return value
  }
  for (const rule of rules) {
    if (!rule || typeof rule !== 'object') continue
    if (rule.oneOf) patchCjsSupport(rule.oneOf)
    if (rule.rules) patchCjsSupport(rule.rules)
    if (rule.test !== undefined) rule.test = patch(rule.test)
    if (rule.exclude !== undefined) rule.exclude = patch(rule.exclude)
  }
}

module.exports = async function (env, argv) {
  env.babel = {
    dangerouslyAddModulePathsToTranspile: ['@bsky.app/expo'],
  }
  let config = await createExpoWebpackConfigAsync(env, argv)
  config = withAlias(config, {
    'react-native$': 'react-native-web',
    'react-native-webview': 'react-native-web-webview',
    'react-native-gesture-handler': false, // RNGH should not be used on web, so let's cause a build error if it sneaks in
    '@sentry-internal/replay': false, // not used, ~300kb of dead weight
  })
  // TEMP HACK: hopefully won't be an issue when we switch to metro
  // @expo/webpack-config's babel-loader and source-map-loader tests do not
  // include .cjs, and its fallback "asset/resource" loader doesn't exclude
  // .cjs — so any dependency whose `require` entrypoint is a .cjs file
  // (e.g. zod 3.24+, unicode-segmenter) gets served as a static asset URL
  // instead of a module. Patch the tests to cover .cjs.
  patchCjsSupport(config.module.rules)
  // react-native-uuid ships sourceMappingURL comments but no .map files.
  patchSourceMapFilter(config.module.rules, /react-native-uuid/)
  config.module.rules = [
    ...(config.module.rules || []),
    reactNativeWebWebviewConfiguration,
  ]
  if (env.mode === 'development') {
    config.plugins.push(new ReactRefreshWebpackPlugin())
    // Reap zombie HMR WebSocket connections that linger after refresh.
    // Without this, dead sockets exhaust the browser's per-origin connection
    // pool and the dev server stops responding.
    config.devServer.onListening = devServer => {
      devServer.server.on('connection', socket => {
        socket.setTimeout(10000)
        socket.on('timeout', () => socket.destroy())
      })
    }
  } else {
    // Support static CDN for chunks
    config.output.publicPath = 'auto'
  }

  if (GENERATE_STATS || OPEN_ANALYZER) {
    config.plugins.push(
      new BundleAnalyzerPlugin({
        openAnalyzer: OPEN_ANALYZER,
        generateStatsFile: true,
        statsFilename: '../stats.json',
        analyzerMode: OPEN_ANALYZER ? 'server' : 'json',
        defaultSizes: 'parsed',
      }),
    )
  }
  if (process.env.SENTRY_AUTH_TOKEN) {
    config.plugins.push(
      sentryWebpackPlugin({
        org: 'blueskyweb',
        project: 'app',
        authToken: process.env.SENTRY_AUTH_TOKEN,
        release: {
          // fallback needed for Render.com deployments
          name: process.env.SENTRY_RELEASE || version,
          dist: process.env.SENTRY_DIST,
        },
      }),
    )
  }
  return config
}