#!/usr/bin/env php

<?php

function check_username($s)
{
    if ( preg_match( "/^[a-zA-Z0-9_.+-]+@/", $s ) == 1 )
    {
        echo("$s has a valid username\n");
        return 1;
    } else {
        echo("$s has no username\n");
        return 0;
    }
}

function check_domain($s)
{
    if ( preg_match( "/@[a-zA-Z0-9-]+(\.[a-zA-Z0-9-]+)*\.[a-zA-Z]{2,4}/", $s ) == 1 )
    {
        echo("$s has a valid domain\n");
        return 1;
    } else {
        echo("$s has invalid domain\n");
        return 0;
    }
}

function check_mail($s)
{
    return check_username($s) * check_domain($s);
}

$mail_array = array( "valid@mail.co", "@invalid.dd", "invalid@inv.d", "valid_mail@com.uk", "valid@long.domain.name.we", "v@e.info", "inv@i.i", "valid+adress_with-all.features908@long-but.valid.domain.name123.co" );

foreach ($mail_array as $mail)
{
    check_mail($mail);
}

?>