TUPLE: parser tex ind res enabled? ;

: when% ( ? quot -- ? ) [ f ] if ; inline
: <parser> ( tex -- parser ) CHAR: \0 suffix 0 0 t parser boa ;
: parser-cur ( parser -- val ) [ ind>> ] [ tex>> ] bi nth ;
: can-continue? ( parser -- ? ) [ ind>> 1 + ] [ tex>> ] bi bounds-check? ;
: parser-next ( parser -- parser ) [ 1 + ] change-ind ;
: run-and-reset ( ..a parser quot: ( ..a parser -- ..b parser ? ) -- ..b parser parsed? ) over clone [ call ] dip [ swapd ? ] keepd ; inline
: match-string ( parser string -- parser parsed? ) t
    [
        [ [ length 0 > ] dip and ] 2check
    ]
    [
        drop unclip swap
        [
            [ dup parser-cur ] dip =
        ] dip swap
        [
            [ parser-next ] 2dip
        ] [ f ] if*
    ] while nip ;
: match-number ( parser -- parser number/f ) [ [ dup [ can-continue? ] [ parser-cur digit? ] bi and ] [ dup parser-cur , parser-next ] while ] "" make dec> ;
: match-character ( parser char -- parser parsed? ) [ dup parser-cur ] dip = [ parser-next t ] when% ;
: parse-mul ( parser -- parser )
    "mul(" match-string
         [
             match-number dup
             [
                 [ CHAR: , match-character ] dip swap
                 [
                     [ match-number ] dip swap [
                         * [ CHAR: right-parenthesis match-character ] dip swap [ [ + ] curry change-res ] [ drop ] if
                     ] [ drop ] if*
                 ] [ drop ] if
             ] [ drop ] if
         ] when ;
: mul-parse ( parser -- parser ) [ dup can-continue? ] [ dup parser-cur CHAR: m = [ parse-mul ] [ parser-next ] if ] while ;

: solve-day-three ( string -- result ) <parser> mul-parse res>> ;

: parse-dodont-or-other ( parser -- parser )
    [ "do()" match-string ] run-and-reset
    [ t >>enabled? ]
    [ "don't()" match-string [ f >>enabled? ] [ parser-next ] if ] if
    ;

: dodont-parse ( parser -- parser ) [ dup can-continue? ] [ dup [ enabled?>> ] [ parser-cur CHAR: m = ] bi and [ parse-mul ] [ parse-dodont-or-other ] if ] while ;

: solve-day-three-part-two ( string -- result ) <parser> dodont-parse res>> ;