! Copyright (C) 2022 Doug Coleman.
! See http://factorcode.org/license.txt for BSD license.
USING: grouping kernel math math.parser sequences splitting ;
IN: 2022-aoc5

: parse-crate-line ( string -- seq )
    4 group harvest
    [ [ "[] " member? ] trim ] { } map-as ;

: parse-move-line ( string -- count,from,to )
    " " split { 1 3 5 } swap nths [ dec> ] map first3 [ 1 - ] bi@ 3array ;

: parse-aoc5-lines ( string -- crates insns )
    "\n\n" split1
    [ split-lines but-last [ parse-crate-line ] map flip [ reverse >vector harvest ] V{ } map-as ]
    [ split-lines [ parse-move-line ] map ] bi* ;

:: do-move ( seqs n from to -- )
    seqs { from to } swap nths first2 '[ _ _ [ pop ] [ push ] bi* ] n swap times ;

:: do-move2 ( seqs n from to -- )
    V{ } clone :> temp
    from seqs nth '[ _ pop temp push ] n swap times
    temp reverse to seqs nth push-all ;

: aoc5-1 ( string -- seqs )
    parse-aoc5-lines
    [ dupd first3 do-move ] each
    [ last ] map concat ;

: aoc5-2 ( string -- seqs )
    parse-aoc5-lines
    [ dupd first3 do-move2 ] each
    [ last ] map concat ;