// Normal Imports
import type { SSRManifest } from 'astro';
import { App } from 'astro/app';
import type { Options } from './types';

// @ts-expect-error
import { fromFileUrl, serveFile, Server } from '@astrojs/deno/__deno_imports.js';

let _server: Server | undefined = undefined;
let _startPromise: Promise<void> | undefined = undefined;

async function* getPrerenderedFiles(clientRoot: URL): AsyncGenerator<URL> {
	// @ts-expect-error
	for await (const ent of Deno.readDir(clientRoot)) {
		if (ent.isDirectory) {
			yield* getPrerenderedFiles(new URL(`./${ent.name}/`, clientRoot));
		} else if (ent.name.endsWith('.html')) {
			yield new URL(`./${ent.name}`, clientRoot);
		}
	}
}

export function start(manifest: SSRManifest, options: Options) {
	if (options.start === false) {
		return;
	}

	const clientRoot = new URL('../client/', import.meta.url);
	const app = new App(manifest);
	const handler = async (request: Request, connInfo: any) => {
		if (app.match(request)) {
			let ip = connInfo?.remoteAddr?.hostname;
			Reflect.set(request, Symbol.for('astro.clientAddress'), ip);
			const response = await app.render(request);
			if (app.setCookieHeaders) {
				for (const setCookieHeader of app.setCookieHeaders(response)) {
					response.headers.append('Set-Cookie', setCookieHeader);
				}
			}
			return response;
		}

		// If the request path wasn't found in astro,
		// try to fetch a static file instead
		const url = new URL(request.url);
		const localPath = new URL('./' + app.removeBase(url.pathname), clientRoot);

		let fileResp = await serveFile(request, fromFileUrl(localPath));

		// Attempt to serve `index.html` if 404
		if (fileResp.status == 404) {
			let fallback;
			for await (const file of getPrerenderedFiles(clientRoot)) {
				const pathname = file.pathname.replace(/\/(index)?\.html$/, '');
				if (localPath.pathname.endsWith(pathname)) {
					fallback = file;
					break;
				}
			}
			if (fallback) {
				fileResp = await serveFile(request, fromFileUrl(fallback));
			}
		}

		// If the static file can't be found
		if (fileResp.status == 404) {
			// Render the astro custom 404 page
			const response = await app.render(request);

			if (app.setCookieHeaders) {
				for (const setCookieHeader of app.setCookieHeaders(response)) {
					response.headers.append('Set-Cookie', setCookieHeader);
				}
			}
			return response;

			// If the static file is found
		} else {
			return fileResp;
		}
	};

	const port = options.port ?? 8085;
	_server = new Server({
		port,
		hostname: options.hostname ?? '0.0.0.0',
		handler,
	});

	_startPromise = Promise.resolve(_server.listenAndServe());
	console.error(`Server running on port ${port}`);
}

export function createExports(manifest: SSRManifest, options: Options) {
	const app = new App(manifest);
	return {
		async stop() {
			if (_server) {
				_server.close();
				_server = undefined;
			}
			await Promise.resolve(_startPromise);
		},
		running() {
			return _server !== undefined;
		},
		async start() {
			return start(manifest, options);
		},
		async handle(request: Request) {
			return app.render(request);
		},
	};
}