import { defineConfig, type Plugin } from "vite";
import react from "@vitejs/plugin-react";

const isolationHeaders = {
  "Cross-Origin-Opener-Policy": "same-origin",
  "Cross-Origin-Embedder-Policy": "require-corp",
  "Cross-Origin-Resource-Policy": "same-origin",
};

function preserveIsolationHeaders(): Plugin {
  const install = (server: { middlewares: { use: (handler: (request: unknown, response: { setHeader: (name: string, value: string) => void }, next: () => void) => void) => void } }) => {
    server.middlewares.use((_request, response, next) => {
      for (const [name, value] of Object.entries(isolationHeaders)) response.setHeader(name, value);
      next();
    });
  };
  return {
    name: "preserve-isolation-headers",
    configureServer: install,
    configurePreviewServer: install,
  };
}

export default defineConfig({
  root: "app",
  plugins: [preserveIsolationHeaders(), react()],
  server: {
    port: 5173,
    strictPort: false,
    headers: {
      ...isolationHeaders,
    },
  },
  preview: {
    headers: {
      ...isolationHeaders,
    },
  },
  build: {
    outDir: "../dist",
    emptyOutDir: true,
  },
});