route(dublin, cork, 200, 'fct').
route(cork, dublin, 200, 'fct').
route(cork, corkAirport, 20, 'fc').
route(corkAirport, cork, 25, 'fc').
route(dublin, dublinAirport, 10, 'fc').
route(dublinAirport, dublin, 20, 'fc').
route(dublinAirport, corkAirport, 225, 'p').
route(corkAirport, dublinAirport, 225, 'p').

% String code values for each mode of transport. I needed to use the string code values as when
% the string is split into a list it converts the individual letters into
% their string code counterparts

mode(102, 5).
mode(99, 80).
mode(116, 100).
mode(112, 500).


% Used this function to get a path from Beginning to end of the journey
path(Begin, End, Path) :-
    path(Begin, End, [Begin], Path).


% Upon reaching the target, the list is reversed

path(End, End, RPath, Path) :-
    reverse(RPath, Path).


% take an edge and check if we have already visited before use
% Use of memberchk implemented below

path(Begin, End, Visited, Path) :-
    route(Begin, Next, _, _),
    \+ memberchk(Next, Visited),
    path(Next, End, [Next|Visited], Path).

% Use of string_to_list to convert the mode string and placed in List_input, which is then reversed and put in Rev_input

journey(A, B, Input_mode) :- path(A, B, X),
        string_to_list(Input_mode, List_input),
        reverse(List_input, Rev_input),
        Y is 0,
        L = X,
        lis(X, Rev_input, Y, X, L),
        nl.

% Used this function to calculate time it takes for mode to reach destination

timeCalc(Velocity, Dist, TMP) :- TMP is ((Dist / Velocity) * 60).


% Used this function to add time taken by different modes together

addTime(TMP, Y, Time) :- Time is TMP + Y.



% This is where I formatted my output, 'L' are the source and destinations and 'H' is the lenght of time it took in minutes.

lis([_|[]], _, _, [H|_], L) :- output(L), write(' would take '), write(H), write(' minutes to travel to.'), !.
lis([H1, H2|T], Rev_input, Y, X, L) :- route(H1, H2, Dist, Mode),
        modeFind(H1, H2, Dist, Mode, Rev_input, Transport),
        mode(Transport, Velocity),
        timeCalc(Velocity, Dist, TMP),
        addTime(TMP, Y, Time),
        lis([H2|T], Rev_input, Time, [Time|X], L).

modeFind(_, _, _, Mode, Rev_input, Transport) :- string_to_list(Mode, Mode_L),
        modeCheck(Rev_input, Mode_L, Transport).

modeCheck([H|_], R_mode, Transport) :- member(H, R_mode), !, Transport is H.
modeCheck([_|T], R_mode, Transport) :- modeCheck(T, R_mode, Transport).


output([]).
output([H|[]]) :-
        write(H), !.
output([H|T]) :-
        write(H),
        write(' --> '),
        output(T).