<?php

namespace Coroutine\Server;

use Kiri\Di\Inject\Container;
use Kiri\Router\Constrict\ConstrictRequest;
use Swoole\Coroutine\Http\Server;
use Swoole\Http\Request;
use Swoole\Http\Response;
use Swoole\WebSocket\CloseFrame;
use Throwable;

abstract class Websocket
{

	#[Container(Transport::class)]
	public Transport $transport;


	/**
	 * @var Config
	 */
	public Config $config {
		get {
			return $this->config;
		}
	}


	/**
	 * @param Config $config
	 * @return void
	 */
	public function start(Config $config): void
	{
		$this->config = $config;
		$this->onStart();
		$server = new Server($config->host, $config->port, false);
		$server->handle('/websocket', fn(Request $request, Response $ws) => $this->handler($request, $ws));
		$server->handle('/online/lists', fn(Request $request, Response $ws) => $this->getLists($request, $ws));
		echo 'websocket server start at ' . $config->host . ':' . $config->port . PHP_EOL;
		$server->start();
	}

	/**
	 * @param Request  $request
	 * @param Response $ws
	 * @return void
	 */
	public function getLists(Request $request, Response $ws): void
	{
		$data = json_encode($this->transport->getLists(), JSON_UNESCAPED_UNICODE);
		$ws->end($data);
	}


	/**
	 * @param Request  $request
	 * @param Response $ws
	 * @return void
	 */
	public function handler(Request $request, Response $ws): void
	{
		try {
			$psr7Request = ConstrictRequest::builder($request);
			if (!$psr7Request->hasQuery($this->config->authKey)) {
				throw new \Exception('Params required.');
			}

			if (!$this->onConnected($psr7Request) || $psr7Request->getAuthority() == null) {
				throw new \Exception('Token error, unable to obtain user.');
			}

			if ($this->transport->has($psr7Request->getAuthority()->getUniqueId())) {
				$this->transport->remove($psr7Request->getAuthority()->getUniqueId());
			}

			if (!$ws->upgrade()) {
				throw new \Exception('Connection upgrade to websocket failed.');
			}

			$userId = $psr7Request->getAuthority()->getUniqueId();
			$ws->push($userId);
			defer(function () use ($userId) {
				$this->transport->remove($userId);
			});

			$this->transport->add($userId, new Struct($psr7Request->getAuthority(), $request, $ws));

			$this->onBeforeMessageLoop();

			while (true) {
				$frame = $ws->recv();
				if ($frame === '' || $frame === false || $frame->data == 'close' || get_class($frame) === CloseFrame::class) {
					$ws->close();
					break;
				}

				$this->onMessage($psr7Request, $frame->data);
			}
		} catch (Throwable $throwable) {
			$this->throwable($ws, $throwable);
		} finally {
			if (isset($userId)) {
				$this->onDisconnect($userId);
			}
		}
	}


	abstract public function onBeforeMessageLoop(): void;


	/**
	 * @param           $ws
	 * @param Throwable $throwable
	 * @return void
	 */
	private function throwable($ws, Throwable $throwable): void
	{
		$error = sprintf("Message: %s \n
			   File: %s \n
			   Line: %d \n", $throwable->getMessage(), $throwable->getFile(), $throwable->getLine());

		$ws->setStatusCode(500);
		$ws->end($throwable->getMessage());
		$ws->close();

		echo $error;
	}


	/**
	 * @param ConstrictRequest $request
	 * @return bool
	 */
	abstract public function onConnected(ConstrictRequest $request): bool;


	/**
	 * @return void
	 */
	abstract public function onStart(): void;


	/**
	 * @param ConstrictRequest $psr7Request
	 * @param string           $frame
	 * @return void
	 */
	abstract public function onMessage(ConstrictRequest $psr7Request, string $frame): void;

	/**
	 * @param int $userId
	 * @return void
	 */
	abstract public function onDisconnect(int $userId): void;
}