<?php
/**
 * Piwik - free/libre analytics platform
 *
 * @link http://piwik.org
 * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
 *
 */
namespace Piwik\Plugins\Marketplace\Api;

use Piwik\Http;

/**
 *
 */
class Service
{
    const CACHE_TIMEOUT_IN_SECONDS = 1200;
    const HTTP_REQUEST_TIMEOUT = 60;

    /**
     * @var string
     */
    private $domain;

    /**
     * @var null|string
     */
    private $accessToken;

    /**
     * API version to use on the Marketplace
     * @var string
     */
    private $version = '2.0';

    public function __construct($domain)
    {
        $this->domain = $domain;
    }

    public function authenticate($accessToken)
    {
        if (empty($accessToken)) {
            $this->accessToken = null;
        } elseif (ctype_alnum($accessToken)) {
            $this->accessToken = $accessToken;
        }
    }

    /**
     * The API version that will be used on the Marketplace.
     * @return string eg 2.0
     */
    public function getVersion()
    {
        return $this->version;
    }

    /**
     * Returns the currently set access token
     * @return null|string
     */
    public function getAccessToken()
    {
        return $this->accessToken;
    }

    public function hasAccessToken()
    {
        return !empty($this->accessToken);
    }

    /**
     * Downloads data from the given URL via a POST request. If a destination path is given, the downloaded data
     * will be stored in the given path and returned otherwise.
     *
     * Make sure to call {@link authenticate()} to download paid plugins.
     *
     * @param string $url An absolute URL to the marketplace including domain.
     * @param null|string $destinationPath
     * @param null|int $timeout  Defaults to 60 seconds see {@link self::HTTP_REQUEST_METHOD}
     * @return bool|string  Returns the downloaded data or true if a destination path was given.
     * @throws \Exception
     */
    public function download($url, $destinationPath = null, $timeout = null)
    {
        $method = Http::getTransportMethod();

        if (!isset($timeout)) {
            $timeout = static::HTTP_REQUEST_TIMEOUT;
        }

        $post = null;
        if ($this->accessToken) {
            $post = array('access_token' => $this->accessToken);
        }

        $file = Http::ensureDestinationDirectoryExists($destinationPath);

        $response = Http::sendHttpRequestBy($method,
                                            $url,
                                            $timeout,
                                            $userAgent = null,
                                            $destinationPath,
                                            $file,
                                            $followDepth = 0,
                                            $acceptLanguage = false,
                                            $acceptInvalidSslCertificate = false,
                                            $byteRange = false, $getExtendedInfo = false, $httpMethod = 'POST',
                                            $httpUsername = null, $httpPassword = null, $post);

        return $response;
    }

    /**
     * Executes the given API action on the Marketplace using the given params and returns the result.
     *
     * Make sure to call {@link authenticate()} to download paid plugins.
     *
     * @param string $action  eg 'plugins', 'plugins/$pluginName/info', ...
     * @param array $params   eg array('sort' => 'alpha')
     * @return mixed
     * @throws Service\Exception
     */
    public function fetch($action, $params)
    {
        $endpoint = sprintf('%s/api/%s/', $this->domain, $this->version);

        $query = http_build_query($params);
        $url   = sprintf('%s%s?%s', $endpoint, $action, $query);

        $response = $this->download($url);

        $result = json_decode($response, true);

        if (is_null($result)) {
            $message = sprintf('There was an error reading the response from the Marketplace: Please try again later.');
            throw new Service\Exception($message, Service\Exception::HTTP_ERROR);
        }

        if (!empty($result['error'])) {
            throw new Service\Exception($result['error'], Service\Exception::API_ERROR);
        }

        return $result;
    }

    /**
     * Get the domain that is used in order to access the Marketplace. Eg http://plugins.piwik.org
     * @return string
     */
    public function getDomain()
    {
        return $this->domain;
    }

}