<?php

namespace GeoIP2\Webservice;

use GeoIP2\Exception\GenericException;
use GeoIP2\Exception\HttpException;
use GeoIP2\Exception\WebserviceException;
use GeoIP2\Model\City;
use GeoIP2\Model\CityIspOrg;
use GeoIP2\Model\Country;
use GeoIP2\Model\Omni;
use Guzzle\Http\Client as GuzzleClient;
use Guzzle\Common\Exception\RuntimeException;
use Guzzle\Http\Exception\ClientErrorResponseException;
use Guzzle\Http\Exception\ServerErrorResponseException;

class Client
{

    private $userId;
    private $licenseKey;
    private $languages;
    private $host;
    private $guzzleClient;

    public function __construct(
        $userId,
        $licenseKey,
        $languages = array('en'),
        $host = 'geoip.maxmind.com',
        $guzzleClient = null
    ) {
        $this->userId = $userId;
        $this->licenseKey = $licenseKey;
        $this->languages = $languages;
        $this->host = $host;
        // To enable unit testing
        $this->guzzleClient = $guzzleClient;
    }

    public function city($ipAddress = 'me')
    {
        return $this->responseFor('city', 'City', $ipAddress);
    }

    public function country($ipAddress = 'me')
    {
        return $this->responseFor('country', 'Country', $ipAddress);
    }

    public function cityIspOrg($ipAddress = 'me')
    {
        return $this->responseFor('city_isp_org', 'CityIspOrg', $ipAddress);
    }

    public function omni($ipAddress = 'me')
    {
        return $this->responseFor('omni', 'Omni', $ipAddress);
    }

    private function responseFor($endpoint, $class, $ipAddress)
    {
        $uri = implode('/', array($this->baseUri(), $endpoint, $ipAddress));

        $client = $this->guzzleClient ?
            $this->guzzleClient : new GuzzleClient();
        $request = $client->get($uri, array('Accept' => 'application/json'));
        $request->setAuth($this->userId, $this->licenseKey);
        $ua = $request->getHeader('User-Agent');
        $ua = "GeoIP2 PHP API ($ua)";
        $request->setHeader('User-Agent', $ua);

        $response = null;
        try {
            $response = $request->send();
        } catch (ClientErrorResponseException $e) {
            $this->handle4xx($e->getResponse(), $uri);
        } catch (ServerErrorResponseException $e) {
            $this->handle5xx($e->getResponse(), $uri);
        }

        if ($response && $response->isSuccessful()) {
            $body = $this->handleSuccess($response, $uri);
            $class = "GeoIP2\\Model\\" . $class;
            return new $class($body, $this->languages);
        } else {
            $this->handleNon200($response, $uri);
        }
    }

    private function handleSuccess($response, $uri)
    {
        if ($response->getContentLength() == 0) {
            throw new GenericException(
                "Received a 200 response for $uri but did not " .
                "receive a HTTP body."
            );
        }

        try {
            return $response->json();
        } catch (RuntimeException $e) {
            throw new GenericException(
                "Received a 200 response for $uri but could not decode " .
                "the response as JSON: " . $e->getMessage()
            );

        }
    }

    private function handle4xx($response, $uri)
    {
        $status = $response->getStatusCode();

        $body = array();

        if ($response->getContentLength() > 0) {
            if (strstr($response->getContentType(), 'json')) {
                try {
                    $body = $response->json();
                    if (!isset($body['code']) || !isset($body['error'])) {
                        throw new GenericException(
                            'Response contains JSON but it does not specify ' .
                            'code or error keys: ' . $response->getBody()
                        );
                    }
                } catch (RuntimeException $e) {
                    throw new HttpException(
                        "Received a $status error for $uri but it did not " .
                        "include the expected JSON body: " .
                        $e->getMessage(),
                        $status,
                        $uri
                    );
                }
            } else {
                throw new HttpException(
                    "Received a $status error for $uri with the " .
                    "following body: " . $response->getBody(),
                    $status,
                    $uri
                );
            }
        } else {
            throw new HttpException(
                "Received a $status error for $uri with no body",
                $status,
                $uri
            );
        }

        throw new WebserviceException(
            $body['error'],
            $body['code'],
            $status,
            $uri
        );
    }

    private function handle5xx($response, $uri)
    {
        $status = $response->getStatusCode();

        throw new HttpException(
            "Received a server error ($status) for $uri",
            $status,
            $uri
        );
    }

    private function handleNon200($response, $uri)
    {
        $status = $response->getStatusCode();

        throw new HttpException(
            "Received a very surprising HTTP status " .
            "($status) for $uri",
            $status,
            $uri
        );
    }

    private function baseUri() {
        return 'https://' . $this->host . '/geoip/v2.0';
    }
}