<?php
namespace ElkenGit\EknotifierPHP;

use console\helpers\Logger;
use GuzzleHttp\Client;
use GuzzleHttp\Psr7\Response;
use Psr\Http\Message\ResponseInterface;

/**
 * Class EKNotifierCommon provide an easy to use integration with the EKNotifier service.
 */
class EknotifierCommon
{
    /**
     * Application credentials.
     *
     * @var string|null
     */
    public $applicationCode, $applicationPassword, $notifierUrl;

    /**
     * Guzzle client.
     *
     * @var Client
     */
    private $httpClient;

    /**
     * Instantiate EknotifierCommon Class.
     *
     * @param string|null $url
     * @param string|null $applicationCode
     * @param string|null $applicationPassword
     * @throws \Exception
     */
    public function __construct(string $url = null, string $applicationCode = null, string $applicationPassword = null)
    {
        $this->httpClient = new Client();

        if (function_exists('config')) {
            $this->notifierUrl = config('eknotifier.url');

            $this->applicationCode = config('eknotifier.app_code');

            $this->applicationPassword = config('eknotifier.app_password');
        } elseif (!$url || !$applicationCode || !$applicationPassword) {
            throw new \Exception('Url, Application Code, or Application Password is missing');
        } else {
            $this->notifierUrl = $url;

            $this->applicationCode = $applicationCode;

            $this->applicationPassword = $applicationPassword;
        }
    }

    /**
     * Get the EKNotifier JWT Token.
     *
     * @return string|null
     * @throws \GuzzleHttp\Exception\GuzzleException
     * @throws \Exception
     */
    public function getAuthToken(): ?string
    {
        if (!cache('eknotifier_token')) {
            $this->login();
        }

        return cache('eknotifier_token');
    }

    /**
     * Login to the EKNotifier Service and cache the key.
     *
     * @return bool
     * @throws \GuzzleHttp\Exception\GuzzleException
     * @throws \Exception
     */
    public function login(): bool
    {
        if (cache('eknotifier_token')) {
            return true;
        }

        $response = $this->postAPI('application/login', [
            'code' => $this->applicationCode,
            'password' => $this->applicationPassword
        ]);


        if ($response->getStatusCode() === 200) {
            $result = json_decode(trim($response->getBody()), true);

            cache(['eknotifier_token' => $result['access_token']], 1800);

            return true;
        }

        return false;
    }

    /**
     * Call EKNotifier POST API.
     *
     * @param string $path
     * @param array $request
     * @param string|null $token
     * @return ResponseInterface
     * @throws \GuzzleHttp\Exception\GuzzleException
     */
    protected function postAPI(string $path, array $request, string $token = null): ResponseInterface
    {
        $url = $this->notifierUrl . '/api/v1/' . $path;

        $params = ['json' => $request];

        if ($token) {
            $params['headers'] = ['Authorization' => 'Bearer ' . $token];
        }

        try {
            return $this->httpClient->request('POST', $url, $params);
        } catch (\Exception $exception) {
            if ($exception instanceof \Exception) {
                Logger::trace('EKNOTIFIER ERROR' . $exception->getResponse()->getBody()->getContents());

                return new Response(
                    $exception->getResponse()->getStatusCode(),
                    $exception->getResponse()->getHeaders(),
                    $exception->getResponse()->getBody()->getContents(),
                    $exception->getResponse()->getProtocolVersion(),
                    $exception->getResponse()->getReasonPhrase()
                );
            }

            Logger::trace('EKNOTIFIER ERROR' . $exception->getMessage());

            return new Response(500, [], $exception->getMessage());
        }
    }
}