#compdef fx

_fx(){

    local state

    _arguments \
        '1: :->action'\
        '*: :->folder_name'

    case $state in 
        (action) _arguments '1:profiles:(s i o)' ;;
                (*) compadd "$@" $(echo $(ls ~/SYNC) | tr \\n ' ')

    esac

}

_fx "$@"