declare function local:maxconsecutive($partite as element()*, $squadra as xs:string, $i as xs:integer, $max as xs:integer, $tot as xs:integer) as xs:integer {
  (if ($i = count($partite)+1) then ( local:max($max, $tot))
    else (
      if (local:vinta($partite[$i], $squadra))
      then (local:maxconsecutive($partite, $squadra, $i+1, $max+1, $tot))
      else (local:maxconsecutive($partite, $squadra, $i+1, 0, local:max($max, $tot)))
    ))
};

declare function local:max($a as xs:integer, $b as xs:integer) as xs:integer {
  (if ($a >= $b) then ($a) else ($b))
};

declare function local:vinta($partita, $squadra) as xs:boolean {
  (($partita/squadracasa = $squadra and $partita/goalcasa > $partita/goalospite) or
  ($partita/squadraospite = $squadra and $partita/goalcasa < $partita/goalospite))
};

let $partite := doc("partite.xml")//partita
return local:maxconsecutive($partite, string("roma"), 1, 0, 0)