import path from 'node:path';
import { svelte } from '@sveltejs/vite-plugin-svelte';
import { defineConfig, loadEnv, type ProxyOptions } from 'vite';

export default defineConfig(({ command, mode }) => {
  const env = loadEnv(mode, process.cwd(), 'DEV_CONSOLE_');
  const target = env.DEV_CONSOLE_API_URL || 'http://localhost:8000';
  const serviceToken = env.DEV_CONSOLE_SERVICE_TOKEN;
  const testVKey = env.DEV_CONSOLE_TEST_VKEY;
  const port = Number(env.DEV_CONSOLE_PORT) || 5173;
  const previewPort = Number(env.DEV_CONSOLE_PREVIEW_PORT) || 4173;

  const missingCredentials = command === 'serve' && (!serviceToken || !testVKey);
  const proxy: Record<string, ProxyOptions> = {
    '/dev-console-api': {
      target,
      changeOrigin: true,
      rewrite: (requestPath) => requestPath.replace(/^\/dev-console-api/, ''),
      configure: (proxyServer) => {
        proxyServer.on('proxyReq', (proxyRequest, request) => {
          if (missingCredentials || !serviceToken || !testVKey) {
            proxyRequest.destroy(
              new Error('Dev Console proxy credentials are not configured on the server.'),
            );
            return;
          }
          proxyRequest.setHeader('Authorization', `Bearer ${serviceToken}`);
          const requestPath = request.url?.split('?', 1)[0] ?? '';
          if (
            request.method === 'POST' &&
            /\/v1\/scoring-runs(?:\/|$)/.test(requestPath)
          ) {
            proxyRequest.setHeader('X-Tenant-VKey', testVKey);
          }
        });
      },
    },
  };

  return {
    plugins: [svelte()],
    resolve: {
      alias: {
        $lib: path.resolve(__dirname, './src/lib'),
      },
    },
    server: {
      port,
      proxy,
    },
    preview: {
      port: previewPort,
      proxy,
    },
  };
});