/**
 * By default, Remix will handle generating the HTTP Response for you.
 * You are free to delete this file if you'd like to, but if you ever want it revealed again, you can run `npx remix reveal` ✨
 * For more information, see https://remix.run/file-conventions/entry.server
 */

import { PassThrough } from 'node:stream'

import type { EntryContext } from '@remix-run/node'
import { createReadableStreamFromReadable } from '@remix-run/node'
import { RemixServer } from '@remix-run/react'
import { isbot } from 'isbot'
import { renderToPipeableStream } from 'react-dom/server'

// eslint-disable-next-line @typescript-eslint/naming-convention
const ABORT_DELAY = 5000

export default async function handleRequest(
	request: Request,
	responseStatusCode: number,
	responseHeaders: Headers,
	remixContext: EntryContext
) {
	return isbot(request.headers.get('user-agent') ?? '')
		? handleBotRequest(
			request,
			responseStatusCode,
			responseHeaders,
			remixContext
		)
		: handleBrowserRequest(
			request,
			responseStatusCode,
			responseHeaders,
			remixContext
		)
}

async function handleBotRequest(
	request: Request,
	responseStatusCode: number,
	responseHeaders: Headers,
	remixContext: EntryContext
) {
	return new Promise((resolve, reject) => {
		let shellRendered = false
		const { pipe, abort } = renderToPipeableStream(
			<RemixServer
				context={remixContext}
				url={request.url}
				abortDelay={ABORT_DELAY}
			/>,
			{
				onAllReady() {
					shellRendered = true
					const body = new PassThrough()
					const stream = createReadableStreamFromReadable(body)

					responseHeaders.set('Content-Type', 'text/html')

					resolve(
						new Response(stream, {
							headers: responseHeaders,
							status: responseStatusCode
						})
					)

					pipe(body)
				},
				onShellError(error: unknown) {
					reject(error)
				},
				onError(error: unknown) {
					responseStatusCode = 500
					// Log streaming rendering errors from inside the shell.  Don't log
					// errors encountered during initial shell rendering since they'll
					// reject and get logged in handleDocumentRequest.
					if (shellRendered) {
						console.error(error)
					}
				}
			}
		)

		setTimeout(abort, ABORT_DELAY)
	})
}

async function handleBrowserRequest(
	request: Request,
	responseStatusCode: number,
	responseHeaders: Headers,
	remixContext: EntryContext
) {
	return new Promise((resolve, reject) => {
		let shellRendered = false
		const { pipe, abort } = renderToPipeableStream(
			<RemixServer
				context={remixContext}
				url={request.url}
				abortDelay={ABORT_DELAY}
			/>,
			{
				onShellReady() {
					shellRendered = true
					const body = new PassThrough()
					const stream = createReadableStreamFromReadable(body)

					responseHeaders.set('Content-Type', 'text/html')

					resolve(
						new Response(stream, {
							headers: responseHeaders,
							status: responseStatusCode
						})
					)

					pipe(body)
				},
				onShellError(error: unknown) {
					reject(error)
				},
				onError(error: unknown) {
					responseStatusCode = 500
					// Log streaming rendering errors from inside the shell.  Don't log
					// errors encountered during initial shell rendering since they'll
					// reject and get logged in handleDocumentRequest.
					if (shellRendered) {
						console.error(error)
					}
				}
			}
		)

		setTimeout(abort, ABORT_DELAY)
	})
}