import { defineConfig } from 'vite'
import react from '@vitejs/plugin-react'
import cesium from 'vite-plugin-cesium'

export default defineConfig({
  plugins: [react(), cesium()],

  optimizeDeps: {
    // Prevent Vite from pre-bundling Cesium — it ships its own worker scripts
    // that must be loaded from a specific public path, not inlined.
    exclude: ['cesium'],
    // Force pre-bundling of @mkkellogg/gaussian-splats-3d and all its CJS
    // transitive dependencies. The 'pkg > dep' syntax tells Vite's esbuild
    // step to convert each dep to ESM when reached through that package.
    // All CJS transitive dependencies of cesium and @mkkellogg/gaussian-splats-3d.
    // Because cesium is in exclude, Vite won't crawl its deps automatically —
    // every CJS package it touches must be listed here for ESM conversion.
    // List generated via: node -e "..." (see vite.config.ts comments above)
    include: [
      '@mkkellogg/gaussian-splats-3d',
      '@mkkellogg/gaussian-splats-3d > mersenne-twister',
      '@mkkellogg/gaussian-splats-3d > urijs',
      'autolinker',
      'bitmap-sdf',
      'dompurify',
      'draco3d',
      'grapheme-splitter',
      'lerc',
      'mersenne-twister',
      'meshoptimizer',
      'nosleep.js',
      'pako',
      'protobufjs',
      'topojson-client',
      'urijs',
    ],
  },

  build: {
    chunkSizeWarningLimit: 4000,
    rollupOptions: {
      output: {
        manualChunks: {
          // cesium is handled by vite-plugin-cesium (served from /Cesium/ public path)
          // and must NOT appear here.
          splat: ['@mkkellogg/gaussian-splats-3d', 'three'],
        },
      },
    },
  },

  server: {
    port: 5173,
    proxy: {
      // Proxy API calls to Django — avoids CORS in development.
      // Django dev server runs on the host at :8000.
      '/api': {
        target: 'http://localhost:8000',
        changeOrigin: true,
      },
    },
  },
})