// <!--GAMFC-->version base on commit 58686d5d125194d34a1137913b3a64ddcf55872f, time is 2024-11-27 09:26:01 UTC<!--GAMFC-END-->.
// @ts-ignore
import { connect } from 'cloudflare:sockets';

// How to generate your own UUID:
// [Windows] Press "Win + R", input cmd and run:  Powershell -NoExit -Command "[guid]::NewGuid()"
let userID = 'd342d11e-d424-4583-b36e-524ab1f0afa4';

let proxyIP = 'saas.sin.fan';


if (!isValidUUID(userID)) {
	throw new Error('uuid is not valid');
}

export default {
	/**
	 * @param {import("@cloudflare/workers-types").Request} request
	 * @param {{UUID: string, PROXYIP: string}} env
	 * @param {import("@cloudflare/workers-types").ExecutionContext} ctx
	 * @returns {Promise<Response>}
	 */
	async fetch(request, env, ctx) {
		try {
			userID = env.UUID || userID;
			proxyIP = env.PROXYIP || proxyIP;
			const upgradeHeader = request.headers.get('Upgrade');
			if (!upgradeHeader || upgradeHeader !== 'websocket') {
				const url = new URL(request.url);
				switch (url.pathname) {
					case '/':
						return new Response(JSON.stringify(request.cf), { status: 200 });
					case `/${userID}`: {
						const vlessConfig = getVLESSConfig(userID, request.headers.get('Host'));
						return new Response(`${vlessConfig}`, {
							status: 200,
							headers: {
								"Content-Type": "text/plain;charset=utf-8",
							}
						});
					}
					default:
						return new Response('Not found', { status: 404 });
				}
			} else {
				return await vlessOverWSHandler(request);
			}
		} catch (err) {
			/** @type {Error} */ let e = err;
			return new Response(e.toString());
		}
	},
};




/**
 * 
 * @param {import("@cloudflare/workers-types").Request} request
 */
async function vlessOverWSHandler(request) {

	/** @type {import("@cloudflare/workers-types").WebSocket[]} */
	// @ts-ignore
	const webSocketPair = new WebSocketPair();
	const [client, webSocket] = Object.values(webSocketPair);

	webSocket.accept();

	let address = '';
	let portWithRandomLog = '';
	const log = (/** @type {string} */ info, /** @type {string | undefined} */ event) => {
		console.log(`[${address}:${portWithRandomLog}] ${info}`, event || '');
	};
	const earlyDataHeader = request.headers.get('sec-websocket-protocol') || '';

	const readableWebSocketStream = makeReadableWebSocketStream(webSocket, earlyDataHeader, log);

	/** @type {{ value: import("@cloudflare/workers-types").Socket | null}}*/
	let remoteSocketWapper = {
		value: null,
	};
	let udpStreamWrite = null;
	let isDns = false;

	// ws --> remote
	readableWebSocketStream.pipeTo(new WritableStream({
		async write(chunk, controller) {
			if (isDns && udpStreamWrite) {
				return udpStreamWrite(chunk);
			}
			if (remoteSocketWapper.value) {
				const writer = remoteSocketWapper.value.writable.getWriter()
				await writer.write(chunk);
				writer.releaseLock();
				return;
			}

			const {
				hasError,
				message,
				portRemote = 443,
				addressRemote = '',
				rawDataIndex,
				vlessVersion = new Uint8Array([0, 0]),
				isUDP,
			} = processVlessHeader(chunk, userID);
			address = addressRemote;
			portWithRandomLog = `${portRemote}--${Math.random()} ${isUDP ? 'udp ' : 'tcp '
				} `;
			if (hasError) {
				// controller.error(message);
				throw new Error(message); // cf seems has bug, controller.error will not end stream
				// webSocket.close(1000, message);
				return;
			}
			// if UDP but port not DNS port, close it
			if (isUDP) {
				if (portRemote === 53) {
					isDns = true;
				} else {
					// controller.error('UDP proxy only enable for DNS which is port 53');
					throw new Error('UDP proxy only enable for DNS which is port 53'); // cf seems has bug, controller.error will not end stream
					return;
				}
			}
			// ["version", "附加信息长度 N"]
			const vlessResponseHeader = new Uint8Array([vlessVersion[0], 0]);
			const rawClientData = chunk.slice(rawDataIndex);

			// TODO: support udp here when cf runtime has udp support
			if (isDns) {
				const { write } = await handleUDPOutBound(webSocket, vlessResponseHeader, log);
				udpStreamWrite = write;
				udpStreamWrite(rawClientData);
				return;
			}
			handleTCPOutBound(remoteSocketWapper, addressRemote, portRemote, rawClientData, webSocket, vlessResponseHeader, log);
		},
		close() {
			log(`readableWebSocketStream is close`);
		},
		abort(reason) {
			log(`readableWebSocketStream is abort`, JSON.stringify(reason));
		},
	})).catch((err) => {
		log('readableWebSocketStream pipeTo error', err);
	});

	return new Response(null, {
		status: