import { defineConfig, type PluginOption } from 'vite';
import react from '@vitejs/plugin-react';

// Coverage instrumentation is opt-in and must stay that way. The plugin rewrites
// every source file to record execution, which is what makes end-to-end coverage
// possible and what must never reach a customer: an instrumented bundle is
// substantially larger and slower, and it publishes the source structure through
// window.__coverage__.
//
// Nothing in the production path sets COVERAGE — the Dockerfile runs a plain
// `npm run build` — so the shipped bundle is uninstrumented. Only the Playwright
// coverage run turns this on, via playwright.config.ts passing it to the dev
// server it starts.
//
// Loaded with a dynamic import rather than at the top of the file because
// vite-plugin-istanbul is ESM-only and this config is evaluated as CommonJS, the
// package having no "type": "module". A static import fails the build outright.
// The upside is that a production build never even resolves the package.
async function coveragePlugins(): Promise<PluginOption[]> {
  if (process.env.COVERAGE !== 'true') return [];
  const { default: istanbul } = await import('vite-plugin-istanbul');
  return [istanbul({ include: 'src/**/*', extension: ['.ts', '.tsx'], requireEnv: false })];
}

export default defineConfig(async () => ({
  plugins: [react(), ...(await coveragePlugins())],
  build: { outDir: 'dist' },
  server: {
    proxy: {
      '/api': 'http://localhost:3000',
      '/uploads': 'http://localhost:3000',
      '/webhooks': 'http://localhost:3000'
    }
  }
}));