import { defineConfig } from 'vite';
import react from '@vitejs/plugin-react';
import tailwindcss from '@tailwindcss/vite';
import path from 'node:path';
import { fileURLToPath } from 'node:url';

const here = fileURLToPath(new URL('.', import.meta.url));

// Dev ports default to the spec values; overridable via env so the e2e run can
// dodge a port that another project is already using (the client uses relative
// URLs, so it follows whatever port Vite binds).
const vitePort = Number(process.env.VITE_PORT ?? 5173);
const apiPort = Number(process.env.HISTORY_API_PORT ?? 4321);

export default defineConfig({
  plugins: [react(), tailwindcss()],
  resolve: {
    alias: {
      '@shared': path.resolve(here, 'shared'),
      '@': path.resolve(here, 'src'),
    },
  },
  server: {
    port: vitePort,
    // The Express backend (tsx) listens on :4321. In dev, proxy the API and the
    // SSE stream to it so the client never needs to know the backend origin.
    proxy: {
      '/api': { target: `http://localhost:${apiPort}`, changeOrigin: true },
      '/sse': { target: `http://localhost:${apiPort}`, changeOrigin: true },
    },
  },
  build: {
    outDir: 'dist',
    emptyOutDir: true,
  },
});