next.config.js

const webpack = require('webpack');

// Direct dependencies that must not be bundled (native modules / server-only)
const serverOnlyPackages = ['node-pty', 'better-sqlite3', 'dockerode'];
// Transitive native deps of dockerode that webpack fails to bundle.
// These are resolved at runtime through dockerode's dependency tree.
const transitiveBundleExcludes = ['ssh2', 'cpu-features'];

/** @type {import('next').NextConfig} */
const nextConfig = {
  async rewrites() {
    // REGISTRY_FIREWALL_URL が設定されている場合のみUIプロキシのrewriteを有効にする。
    // 未設定時はrewriteを登録しないことで、タイムアウトせず即座に404を返す。
    const registryFirewallUrl = process.env.REGISTRY_FIREWALL_URL;
    if (!registryFirewallUrl) {
      return [];
    }
    return [
      {
        source: '/api/registry-firewall/ui/:path*',
        destination: `${registryFirewallUrl}/ui/:path*`,
      },
    ];
  },
  // Server-side only packages (native modules that can't be bundled)
  serverExternalPackages: serverOnlyPackages,
  // Exclude frontend directory from build (used by Syncthing sync)
  typescript: {
    // Ignore build errors in excluded directories
    ignoreBuildErrors: false,
  },
  // Exclude specific directories from being processed
  pageExtensions: ['tsx', 'ts', 'jsx', 'js'],
  // Transpile packages that have Turbopack compatibility issues
  transpilePackages: ['react-diff-viewer-continued'],
  // Turbopack設定（Next.js 16でデフォルト有効）
  turbopack: {
    // react-diff-viewer-continuedがWorkerで.tsファイルを参照しようとする問題を回避
    resolveAlias: {
      './computeWorker.ts': './computeWorker.js',
    },
    resolveExtensions: ['.ts', '.tsx', '.js', '.jsx', '.json'],
  },
  webpack: (config, { isServer }) => {
    // Ignore the frontend directory
    config.watchOptions = {
      ...config.watchOptions,
      ignored: ['**/frontend/**', '**/backend/**'],
    };

    // react-diff-viewer-continuedがWorkerで.tsファイルを参照しようとする問題を回避
    // NormalModuleReplacementPluginで.ts参照を.jsに置き換える
    config.plugins.push(
      new webpack.NormalModuleReplacementPlugin(
        /\.\/computeWorker\.ts$/,
        './computeWorker.js'
      )
    );

    // サーバー側ビルドでネイティブモジュールを外部化
    if (isServer) {
      const allExternals = [...serverOnlyPackages, ...transitiveBundleExcludes];
      const nativeExternals = Object.fromEntries(
        allExternals.map(pkg => [pkg, `commonjs ${pkg}`])
      );
      if (typeof config.externals === 'function') {
        config.externals = [config.externals, nativeExternals];
      } else if (Array.isArray(config.externals)) {
        config.externals.push(nativeExternals);
      } else if (config.externals) {
        config.externals = [config.externals, nativeExternals];
      } else {
        config.externals = [nativeExternals];
      }
    }

    return config;
  },
}

module.exports = nextConfig