import { promises as fs } from 'fs'
import { builtinModules, createRequire } from 'module'
import { resolve } from 'path'
import { fileURLToPath } from 'url'
import { type RollupOptions, defineConfig } from 'rollup'
import { nodeResolve } from '@rollup/plugin-node-resolve'
import commonjs from '@rollup/plugin-commonjs'
import esbuild from 'rollup-plugin-esbuild'
import json from '@rollup/plugin-json'
import replace from '@rollup/plugin-replace'
import alias from '@rollup/plugin-alias'
import dts from 'rollup-plugin-dts'

const require = createRequire(import.meta.url)
const pkg = require('./package.json')

const DEV = !!process.env.DEV
const PROD = !DEV

const ROOT = fileURLToPath(import.meta.url)
const r = (p: string) => resolve(ROOT, '..', p)

const external = [
  ...Object.keys(pkg.dependencies),
  ...Object.keys(pkg.peerDependencies),
  ...builtinModules.flatMap((m) =>
    m.includes('punycode') ? [] : [m, `node:${m}`]
  )
]

const plugins = [
  alias({
    entries: {
      'readable-stream': 'stream'
    }
  }),
  replace({
    // polyfill broken browser check from bundled deps
    'navigator.userAgentData': 'undefined',
    'navigator.userAgent': 'undefined',
    preventAssignment: true
  }),
  commonjs(),
  nodeResolve({ preferBuiltins: false }),
  esbuild({ target: 'node18' }),
  json()
]

const esmBuild: RollupOptions = {
  input: [r('src/node/index.ts'), r('src/node/cli.ts')],
  output: {
    format: 'esm',
    entryFileNames: `[name].js`,
    chunkFileNames: 'serve-[hash].js',
    dir: r('dist/node'),
    sourcemap: DEV
  },
  external,
  plugins,
  onwarn(warning, warn) {
    if (warning.code !== 'EVAL') warn(warning)
  }
}

const typesExternal = [
  ...external,
  /\/vitepress\/(?!(dist|node_modules)\/).*\.d\.ts$/,
  'source-map-js',
  'fast-glob'
]

const nodeTypes: RollupOptions = {
  input: r('src/node/index.ts'),
  output: {
    format: 'esm',
    file: 'dist/node/index.d.ts'
  },
  external: typesExternal,
  plugins: [dts({ respectExternal: true })]
}

// const clientTypes: RollupOptions = {
//   input: r('dist/client-types/index.d.ts'),
//   output: {
//     format: 'esm',
//     file: 'dist/client/index.d.ts'
//   },
//   external: typesExternal,
//   plugins: [
//     dts({ respectExternal: true }),
//     {
//       name: 'cleanup',
//       async closeBundle() {
//         if (PROD) {
//           await fs.rm(r('dist/client-types'), { recursive: true })
//         }
//       }
//     }
//   ]
// }

const config = defineConfig([])

config.push(esmBuild)
config.push(nodeTypes)
// config.push(clientTypes)

export default config