preg_match major bots

<?php
    /* Grab Major bots name and version
        Hello everyone thats see this this is a beta code that i made isn't 100%
        but so far its working for the list of bots that i add it
        if you wanna help me to improve this code please send email to toslalompt@gmail.com
        with corrections,...
    */
    /*
        this ereg aint 100% but if you want to help me to improve feel free to comment/update via email Thankyou
        im starting in php so :)
    */
    $majorbots .= '(' ;
    $majorbots .= '[A-Za-z]+[A-Za-z-.: ]+|[A-Za-z-_.: ]+' ;
    $majorbots .= '(bot|robot|spider|crawler|curl)' ;
    $majorbots .= ')' ;
    $majorbots .= '[\/ ]?' ;
    $majorbots .= '([v]?[0-9]*\.?[0-9a-z\.]+)?' ;
    // the rest of the ua string
    $majorbots .= '(.*)' ;

    /* List of bots i tested */
    $bots = array (
    'Mozilla/5.0 (compatible; DuckDuckGo-Favicons-Bot/1.0; +http://www.google.com/bot.html)' ,
    'Mozilla/5.0 (compatible; Sogou Orionbot 3.0' ,
    'Adidxbot/v4.1.0' ,
    'crawler for netopian (http://www.netopian.co.uk/)' ,
    'boitho.com-robot/1.1' ,
    'SEMrushBot' ,
    'eBot / v.1.0a (http://alfa.elchron.cz)' ,
    'envolk[ITS]spider/1.6 ( http://www.envolk.com/envolkspider.html)' ,
    'SpeedySpider - http://www.entireweb.com',
    'Bot mailto:craftbot@yahoo.com' ,
    'Sogou News Spider/4.0(+http://www.sogou.com/docs/help/webmasters.htm#07)',
    'Mozilla/5.0 (compatible; DuckDuckGo Favicons-Bot/1.0 +http://www.google.com/bot.html)' ,
    'Mozilla/5.0 (compatible; Konqueror/3.5; Linux) KHTML/3.5.5 (like Gecko) (Exabot-Thumbnails)' ,
    'Mozilla/5.0 (compatible; Exabot/3.0; +http://www.exabot.com/go/robot)' ,
    'Mozilla/5.0 (compatible; Mail.RU_Bot/2.0; +http://go.mail.ru/help/robots)',
    'Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) AddSugarSpiderBot www.idealobserver.com' ,
    'Mozilla/4.0 (compatible; BlitzBot)' ,
    'Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)' ,
    'FAST Enteprise Crawler/6 (www dot fastsearch dot com)',
    'TinEye-bot/0.51 (see http://www.tineye.com/crawler.html)' ,
    'Whoismindbot/1.0 (+http://www.whoismind.com/bot.html)' ,
    'yacybot (/global; amd64 Linux 4.4.0-31-generic; java 1.8.0_91; Europe/en) http://yacy.net/bot.html' ,
    'StatoolsBot (+http://www.statools.com/bot.html)',
    'adidxbot/2.0 (+http://search.msn.com/msnbot.htm)' ,
    'BlitzBOT@tricus.net (Mozilla compatible)' ,
    'BlitzBOT@tricus.com (Mozilla compatible)' ,
    'ConveraCrawler/0.9d (+http://www.authoritativeweb.com/crawl)',
    'EmeraldShield.com WebBot (http://www.emeraldshield.com/webbot.aspx)' ,
    ) ;

    // http://www.useragentstring.com/pages/useragentstring.php?typ=Crawler
    echo ' testing '.count ( $bots ).' bots <br/> ' ;
    $pregRep  = "{\(|\)|]|\[}" ;
    $numbDots = "[a-zA-Z0-9.]+" ;
    $clean    = array ( $pregRep , "/mozilla\/".$numbDots." compatible;/" , "/windows nt ".$numbDots."/" , "/like gecko /" , "/linux khtml\/".$numbDots."/" ) ;
    $count    = 1 ;
    foreach ( $bots as $key => $bot ) {
        // ereg to ( and ) and [ and ] from useragent
        // make full string lower
        $useragent = strtolower ( $bot ) ;
        // remove the words from useragent that i put in ereg
        $useragent = preg_replace ( $clean , '' , $useragent ) ;
        // remove the space that of some useragents have
        $useragent = preg_replace ( "{ \/ }" , '/' , $useragent ) ;
        // simple function to revome url from useragent and -
        $useragent = preg_replace ( "@http://(.*)| - http://(.*)$@" , '' , $useragent ) ;
        // now lets start checking
        // 1 going to check if is a bot
        if ( preg_match("/(bot|crawl|slurp|spider)/" , $useragent ) ) {
            // since its a bot now
            if ( preg_match ( "#^".$majorbots."$#" , $useragent , $match ) ) {
                // just to check wich boot im working with
                echo ' this bot is '.$bots[$key].' <br/> ';
                // and now print bot info with 6 fields
                echo ' print '.$count.' <br/> <pre>  ' . print_r ( $match , 1 ) . '</pre>';
                // example
                /*
                (
                    [0] => full string clean with my str_replace
                    [1] => bot name
                    [2] => bot|crawl|slurp|spider
                    [3] => bot version
                    [4] => rest of the bot sctring
                )
                */
            }
        }
        $count++ ;
    }
?>