/// <reference types="vitest/config" />
import react from '@vitejs/plugin-react'
import { defineConfig, type ProxyOptions } from 'vite'

// The Go API behind this dev server. Override when the API runs elsewhere,
// e.g. API_URL=http://127.0.0.1:8080 npm run dev.
const apiUrl = process.env.API_URL ?? 'http://localhost:8080'

// /api is proxied so the browser only ever sees the vite origin
// (localhost or *.preview.k6n.net): OIDC redirects land on the same host
// and session cookies stay first-party. X-Forwarded-Host/Proto tell the
// backend which public origin to bake into redirect URIs — behind the
// preview ingress the incoming request already carries a forwarded proto,
// which wins over the local http connection.
const apiProxy: ProxyOptions = {
  target: apiUrl,
  configure: (proxy) => {
    proxy.on('proxyReq', (proxyReq, req) => {
      const host = req.headers.host
      if (host !== undefined) proxyReq.setHeader('X-Forwarded-Host', host)
      const protoHeader = req.headers['x-forwarded-proto']
      const local = (req.socket as { encrypted?: boolean }).encrypted ? 'https' : 'http'
      const proto = (Array.isArray(protoHeader) ? protoHeader[0] : protoHeader) ?? local
      proxyReq.setHeader('X-Forwarded-Proto', proto)
    })
  },
}

// https://vite.dev/config/
export default defineConfig({
  plugins: [react()],
  server: {
    host: '0.0.0.0',
    port: 5173,
    allowedHosts: ['.preview.k6n.net'],
    proxy: {
      '/api': apiProxy,
    },
  },
  test: {
    globals: true,
    environment: 'jsdom',
    setupFiles: ['./tests/setup.ts'],
    include: ['tests/**/*.test.{ts,tsx,mjs}', 'src/**/*.test.{ts,tsx}'],
    // jsdom forks are memory-hungry; parallel workers can OOM on busy hosts.
    maxWorkers: 2,
  },
})