import { Elysia, status } from 'elysia'
import { readFileSync } from 'node:fs'
import { fileURLToPath } from 'node:url'

const PORT = process.env.PORT || 3000

// Resolve index.html next to this file, so it works no matter where you run it from.
const INDEX_HTML = readFileSync(fileURLToPath(new URL('./index.html', import.meta.url)), 'utf8')

const HTML_HEADERS = {
  'content-type': 'text/html; charset=utf-8',
  'content-length': String(Buffer.byteLength(INDEX_HTML)),
}

// The food menu data.
const menu = [
  { id: 1, food: 'Adobo', price: 75 },
  { id: 2, food: 'Fried Chicken', price: 50 },
  { id: 3, food: 'Yum Burger', price: 70 },
]

// Elysia serves through Bun.serve on Bun, but it needs the Node adapter on Node.
// This one file therefore runs on either runtime: `bun server.js` or `node server.js`.
const adapter =
  typeof Bun === 'undefined' ? (await import('@elysiajs/node')).node() : undefined

new Elysia(adapter ? { adapter } : {})
  .onRequest(({ request }) => {
    if (request.method !== 'GET') {
      return status(405, { error: 'Method not allowed' })
    }
  })

  // GET /api/menu -> the whole menu
  .get('/api/menu', () => menu)

  // GET /api/menu/:id -> one item
  .get('/api/menu/:id', ({ params: { id }, status }) => {
    const num = Number(id)

    if (!Number.isInteger(num) || num < 1) {
      return status(400, { error: 'ID must be a whole number, like 1.' })
    }

    const item = menu.find((food) => food.id === num)
    if (!item) {
      return status(404, { error: `No menu item with ID ${num}.` })
    }

    return item
  })

  // GET / -> the frontend
  .get('/', () => new Response(INDEX_HTML, { headers: HTML_HEADERS }))
  .get('/index.html', () => new Response(INDEX_HTML, { headers: HTML_HEADERS }))

  .get('*', () => status(404, 'Not found'))

  .listen(PORT)

const runtime = typeof Bun === 'undefined' ? 'Node.js' : 'Bun'
console.log(`Meal API running at http://localhost:${PORT} (${runtime})`)