// vim: set noexpandtab:
import mime from 'mime'
import GoogleDrive from './googleDrive'

self.props = {
	root_id: typeof(ROOT_ID) !== 'undefined' ? ROOT_ID : 'root',
	client_id: typeof(CLIENT_ID) !== 'undefined' ? CLIENT_ID : '202264815644.apps.googleusercontent.com',
	client_secret: typeof(CLIENT_SECRET) !== 'undefined' ? CLIENT_SECRET : 'X4Z3ca8xfWDb1Voo-F9a7ZxJ',
	refresh_token: typeof(REFRESH_TOKEN) !== 'undefined' ? REFRESH_TOKEN : '' // left here for debugging
}

const gd = new GoogleDrive(self.props)

async function onGet(request) {
	let { pathname: path } = request
	const rootId =
		request.searchParams.get('rootId') || self.props.root_id
	const result = await gd.getMetaByPath(path, rootId)
	if (!result || result.mimeType.includes('vnd.google-apps')) {
		return new Response('404 Not Found', {
			headers: {
				'Content-Type': 'text/plain'
			},
			status: 404
		})
	}
	const r = await gd.download(result.id, request.headers.get('Range'))
	const h = new Headers(r.headers)
	h.set(
		'Content-Disposition',
		`inline; filename*=UTF-8''${encodeURIComponent(result.name)}`
	)
	return new Response(r.body, {
		status: r.status,
		headers: h
	})
}

function encodePathComponent(path) {
	return path
		.split('/')
		.map(encodeURIComponent)
		.join('/')
}

async function handleRequest(request) {
	if (request.method === 'OPTIONS')
		// allow preflight request
		return new Response('', {
			status: 200,
			headers: {
				'Access-Control-Allow-Origin': '*',
				'Access-Control-Allow-Headers': '*',
				'Access-Control-Allow-Methods': 'GET, HEAD, OPTIONS'
			}
		})
	request = Object.assign({}, request, new URL(request.url))
	request.pathname = request.pathname
		.split('/')
		.map(decodeURIComponent)
		.map(decodeURIComponent) // for some super special cases, browser will force encode it...   eg: +αあるふぁきゅん。 - +♂.mp3
		.join('/')

	if (request.pathname.endsWith('/')) request.pathname += 'index.html'

	let resp
	if (request.method === 'GET') resp = await onGet(request)
	else
		resp = new Response('', {
			status: 405
		})
	const obj = Object.create(null)
	for (const [k, v] of resp.headers.entries()) {
		obj[k] = v
	}
	return new Response(resp.body, {
		status: resp.status,
		statusText: resp.statusText,
		headers: Object.assign(obj, {
			'Access-Control-Allow-Origin': '*'
		})
	})
}

addEventListener('fetch', event => {
	event.respondWith(
		handleRequest(event.request).catch(err => {
			console.error(err)
			new Response(JSON.stringify(err.stack), {
				status: 500,
				headers: {
					'Content-Type': 'application/json'
				}
			})
		})
	)
})