:- use_module(library(http/json)).

main :-
    current_input(Stream),
    json_read_dict(Stream,GameDict),
    close(Stream),
    do_move(GameDict,NewGameDict),
%    get_dict(turn, GameDict, X),
%    print(X),
%    print(BoardString), nl,
%    split_string(BoardString, "|", "", BoardList),
%    print(BoardList), nl,

%    nth0(1,BoardList,X2),
%    print(X2), nl,
%    string_chars(X2,X3),
%    print(X3), nl,
%    nth0(1,X3,X4),
%    print(X4), nl,
%    print("aaa"), nl,

    current_output(OutStream),
    json_write_dict(OutStream, NewGameDict),
    close(OutStream).

do_move(GameDict, NewGameDict) :-
    GameDict = _{
        turn:Turn,
        size:_{
            columns:ColumnCount,
            rows:RowCount
        },
        board:BoardString,
        variant:Variant,
        capability:Capability,
        status:_{
            winner:Winner,
            finished:Finished
        },
        show_all:ShowAll
    },

%    print(BoardString), nl,
    split_string(BoardString, "|", "", BoardList),
    ColumnCount0 is ColumnCount - 1,
    next_moves(BoardList, NextMoves, ColumnCount0, RowCount, Turn),
    print(NextMoves), nl,
%    print(BoardList), nl,
    NewGameDict = GameDict.

next_moves(Board, [], -1, _, _).
next_moves(Board, [Move|Moves], ColumnsLeft, RowCount, Turn) :- %Note: ColumnsLeft is 0-indexed, and must start at 1 less than the amount of columns!
    ColumnsLeft >= 0,
    print("iterate: "), print(ColumnsLeft), nl, %TODO remove duplicate code?
    nth0(ColumnsLeft, Board, Col),
    print(Col), nl,
    string_length(Col, Len),
    print(Len), nl,
    Len < RowCount,
    print("check"), nl,
    string_concat(Col, Turn, NewColumn),
    print(NewColumn), nl,
    replaceAt(Board, ColumnsLeft, NewColumn, Move),
    print(Move), nl,
    NewColumnsLeft is ColumnsLeft - 1,
    print(NewColumnsLeft), nl,
    next_moves(Board, Moves, NewColumnsLeft, RowCount, Turn),
    print("EndIteration"), nl.
next_moves(Board, Moves, ColumnsLeft, RowCount, Turn) :-
    ColumnsLeft >= 0,
    nth0(ColumnsLeft, Board, Col),
    string_length(Col, Len),
    Len >= RowCount,
    NewColumnsLeft is ColumnsLeft - 1,
    next_moves(Board, Moves, NewColumnsLeft, RowCount, Turn).


replaceAt([_|T], 0, X, [X|T]).
replaceAt([H|T], I, X, [H|R]) :- I > 0, I1 is I-1, replaceAt(T, I1, X, R), !.
replaceAt(L, _, _, L).

%has_won(BoardList, Player) :-
%    tolistlist(BoardList, BoardListList),

win_right_from(BoardListList, StartHeight, StartColumn, MaxHeight, Player, ChecksLeft) :-
    length(BoardListList, NumCols),
    Val is NumCols - StartColumn,
    Val >= ChecksLeft,
    win_right_straight(BoardListList, StartHeight, StartColumn, MaxHeight, Player, ChecksLeft);
    win_right_up(BoardListList, StartHeight, StartColumn, MaxHeight, Player, ChecksLeft);
    win_right_down(BoardListList, StartHeight, StartColumn, MaxHeight, Player, ChecksLeft).

win_right_straight(_, _, _, _, _, 0).
win_right_straight(BoardListList, StartHeight, StartColumn, MaxHeight, Player, ChecksLeft) :- %TODO more efficient/add !
%   !,
    nth0(StartColumn, BoardListList, Col),
    nth0(StartHeight, Col, El),
    El = Player,
    NewCol is StartColumn + 1,
    NewChecks is ChecksLeft - 1,
    win_right_straight(BoardListList, StartHeight, NewCol, MaxHeight, Player, NewChecks).

win_right_up(_, _, _, _, _, 0).

win_right_down(_, _, _, _, _, 0).




tolistlist([], []).
tolistlist([H|T],[H2|T2]) :-
    string_chars(H, H2),
    tolistlist(T, T2).

% Wrong replace - replaces element, not element at index!
replaceP(_, _, [], []).
replaceP(O, R, [O|T], [R|T2]) :- replaceP(O, R, T, T2).
replaceP(O, R, [H|T], [H|T2]) :- dif(H,O), replaceP(O, R, T, T2).