<?php
/**
 * Class regrouping basic methods for download page.
 *
 * @copyright 2009-2011  Romain d'Alverny <rda>
 * @license GPL-3+
 *
*/
class Downloads
{
    /**
     * @param string $country matches the URI base dir
     * @param string $locale
    */
    function __construct($locale = 'en', $cache = null)
    {
        $this->_locale  = $locale;
    }
    /**
     * @param string $ua
     *
     * @return array
    */
    public static function get_platform($ua = null)
    {
        if ($ua == '')
            return array(
                'arch'   => 'i586',
                'system' => 'unknow',
                'locale' => 'en',
                'browser' => null
            );

        $locale = null;
        if (preg_match_all('/([.^\(^\)]*) \((.*)\) (.*)/', $ua, $r))
        {
            $r = $r[2][0];
            $r = explode(';', $r);
            $r = explode(')', trim($r[3]));
            if (strlen($r[0]) > 5)
                $r = substr($r[0], 0, 5);
            else
                $r = $r[0];
            $locale = $r;
        }

        $arch = 'i586';
        if (strpos($ua, 'x86_64') !== false)
            $arch = 'x86_64';

        $sys = null;
        if (strpos($ua, 'Windows') !== false)
            $sys = 'win';
        elseif (strpos($ua, 'Macintosh') !== false
            || strpos($ua, 'Mac OS X') !== false)
            $sys = 'mac';
        elseif (strpos($ua, 'Linux') !== false)
            $sys = 'linux';

        $browser = null;
        if (strpos($ua, 'Firefox') !== false)
            $browser = 'firefox';
        elseif (strpos($ua, 'MSIE') !== false)
            $browser = 'msie';
        elseif (strpos($ua, 'Safari') !== false)
            $browser = 'safari';
        elseif (strpos($ua, 'Opera') !== false)
            $browser = 'opera';

        return array(
            'arch'   => $arch,
            'system' => $sys,
            'locale' => $locale,
            'browser' => $browser
        );
    }

    /**
    */
    public static function get_all_mirrors()
    {
        $prod = true;
        $cache_file = '../../lib/cached.list.php';

        if ($prod) {
            require $cache_file;
            return $mirrors;
        }

        // @todo cache this!
        $data = file('http://mirrors.mageia.org/api/foo.Cauldron.i586.list');
        $mirrors3 = array();
        foreach ($data as $line) {
            $line = explode(',', trim($line));
            foreach ($line as $val) {
                $val = explode('=', trim($val));
                $m[$val[0]] = $val[1];
            }
            $pu = parse_url($m['url']);
            if (in_array($pu['scheme'], array('http', 'https', 'ftp')))
                $mirrors3[$m['country']][] = array(
                    'city' => $m['city'],
                    'zone' => $m['zone'],
                    'url' => str_replace('/distrib/cauldron/i586', '', $m['url'])
                );
        }
        
        /*
        file_put_contents($cache_file,
            sprintf('<?php $mirrors = %s; ?>',
                    var_export($mirrors3, true)));
        //*/

        return $mirrors3;
    }

    /**
    */
    function get_mirror($country)
    {
        $mirs = self::get_all_mirrors();
        
        if (array_key_exists($country, $mirs))
        {
            $mirs = $mirs[$country];
            shuffle($mirs);
            return array_shift($mirs);
        }
        else
        {
            shuffle($mirs);
            $mirs = array_shift($mirs);
            shuffle($mirs);
            return array_shift($mirs);
        }
    }

    /**
     * Queries a GeoIP db for $ip to get the country.
     *
     * @param string $ip
     *
     * @return string
     *
     * If fail, use $country as a fallback to return.
     * @see http://www.maxmind.com/app/php & http://www.maxmind.com/app/geoip_country
     * It has limitations too & needs to be updated from time to time.
     *
     * @todo make a separate class for this.
     * @todo unit tests for this!
    */
    function get_country($ip)
    {
        if ($ip == '127.0.0.1' || $ip == '::1')
            return null;

        if (function_exists('geoip_country_code_by_name'))
        {
            $loc = geoip_country_code_by_name($ip);
        }
        else
        {
            require_once '../../lib/maxmind/geoip/geoip.inc.php';
            $gi = geoip_open(realpath('../../lib/maxmind/geoip/GeoIP.dat'),
                GEOIP_STANDARD);
            $loc = geoip_country_code_by_addr($gi, $ip);
            geoip_close($gi);
        }
        if (trim($loc) == '' || is_null($loc))
            return null;

        return strtoupper($loc);
    }

    /**
     * Setup session data about current visitor for downloads.
     *
     * @param string $version
     * @param boolean $force
     *
     * @return array
    */
    function prepare_download($version, $force = false)
    {
        $fuzzy_mirror = false;

        if (isset($_GET['country']))
        {
            $country = $_GET['country'];
            $force = true;
        }
        
        if (!$force && isset($_SESSION['dl-data']))
        {
            //error_log(sprintf('Got session data: %s', print_r($_SESSION['dl-data'], true)));
            $system  = $_SESSION['dl-data']['system'];
            if (isset($_GET['mirror']))
            {
                $mirror = array('url' => $_GET['mirror']);
                $mirror['purl'] = parse_url($mirror['url']);
                $_SESSION['dl-data']['mirror'] = $mirror;
                $country = '';
            }
            else
            {
                $country = $_SESSION['dl-data']['country'];
                $mirror  = $_SESSION['dl-data']['mirror'];
            }
        }
        else
        {
            //error_log('getting platform');
            $system = self::get_platform($_SERVER['HTTP_USER_AGENT']);
            if (isset($_GET['mirror']))
            {
                $mirror = array('url' => $_GET['mirror']);
                $mirror['purl'] = parse_url($mirror['url']);
                $country = '';
            }
            else
            {
                //error_log('no mirror set yet');
                if (isset($_SERVER['HTTP_X_FORWARDED_FOR'])
                    && $str = $_SERVER['HTTP_X_FORWARDED_FOR'])
                {
                    $arr = explode(', ', $str);
                    $ip  = $arr[0];
                }
                else
                    $ip = $_SERVER['REMOTE_ADDR'];

                $_SESSION['ip'] = $ip;
                if (isset($_GET['country']))
                    $country = $_GET['country'];
                else
                    $country = self::get_country($ip);

                $mirror = $this->get_mirror($country);
                $fuzzy_mirror = is_null($country) ? true : false;

                $mirror['purl'] = parse_url($mirror['url']);
                
                // reassign country, as get_one_mirror() may have decided
                // to return a mirror from another country than the one
                // requested initially - @see get_one_mirror()
                $country = $mirror['zone'];

                if (is_null($mirror)) {
                    // @todo?
                }
            }
            $_SESSION['dl-data'] = array(
                'system'  => $system,
                'country' => $country,
                'mirror'  => $mirror
            );
            //echo "<pre>Got NEW session data:", print_r($_SESSION['dl-data'], true), '</pre>';
        }
        //
        return array(
            'arch'          => $system['arch'],
            'mirror_host'   => $mirror['purl']['host'],
            'mirror_scheme' => $mirror['purl']['scheme'],
            'mirror_url'    => $mirror['url'],
            'country'       => $country,
            'fuzzy_mirror'         => $fuzzy_mirror
        );
    }
}