import { defineConfig } from 'vite';
import react from '@vitejs/plugin-react';
import electron from 'vite-plugin-electron';
import renderer from 'vite-plugin-electron-renderer';
import { resolve } from 'path';
import { existsSync, readFileSync } from 'fs';

function getExtensionPackages(): Set<string> {
  try {
    const manifestPath = resolve(__dirname, 'clawx-extensions.json');
    if (!existsSync(manifestPath)) return new Set();
    const manifest = JSON.parse(readFileSync(manifestPath, 'utf-8'));
    const allIds: string[] = [
      ...(manifest.extensions?.main ?? []),
      ...(manifest.extensions?.renderer ?? []),
    ];
    const pkgs = new Set<string>();
    for (const id of allIds) {
      if (id.startsWith('builtin/')) continue;
      const parts = id.split('/');
      pkgs.add(parts[0].startsWith('@') ? parts.slice(0, 2).join('/') : parts[0]);
    }
    return pkgs;
  } catch {
    return new Set();
  }
}

const extensionPackages = getExtensionPackages();

function isMainProcessExternal(id: string): boolean {
  if (!id || id.startsWith('\0')) return false;
  if (id.startsWith('.') || id.startsWith('/') || /^[A-Za-z]:[\\/]/.test(id)) return false;
  if (id.startsWith('@/') || id.startsWith('@electron/')) return false;
  for (const pkg of extensionPackages) {
    if (id === pkg || id.startsWith(pkg + '/')) return false;
  }
  return true;
}

// https://vitejs.dev/config/
export default defineConfig({
  // Required for Electron: all asset URLs must be relative because the renderer
  // loads via file:// in production. vite-plugin-electron-renderer sets this
  // automatically, but we declare it explicitly so the intent is clear and the
  // build remains correct even if plugin order ever changes.
  base: './',
  plugins: [
    react(),
    electron([
      {
        // Main process entry file
        entry: 'electron/main/index.ts',
        onstart(options) {
          options.startup();
        },
        vite: {
          build: {
            outDir: 'dist-electron/main',
            rollupOptions: {
              external: isMainProcessExternal,
            },
          },
        },
      },
      {
        // Preload scripts entry file
        entry: 'electron/preload/index.ts',
        onstart(options) {
          options.reload();
        },
        vite: {
          build: {
            outDir: 'dist-electron/preload',
            rollupOptions: {
              external: ['electron'],
            },
          },
        },
      },
    ]),
    renderer(),
  ],
  resolve: {
    alias: {
      '@': resolve(__dirname, 'src'),
      '@electron': resolve(__dirname, 'electron'),
    },
  },
  server: {
    port: 5173,
  },
  build: {
    outDir: 'dist',
    emptyOutDir: true,
  },
});