world.lp

% Maps a location of a node based on init
location(object(node,N),pair(X,Y),0) 	:- init(object(node,N),value(at,pair(X,Y))).
object(node,N) 							:- init(object(node,N),value(at,pair(X,Y))).

% Maps a location of a highway based on init
location(object(highway,H),pair(X,Y),0)	:- init(object(highway,H),value(at,pair(X,Y))).
object(highway,H) 						:- init(object(highway,H),value(at,pair(X,Y))).

% Maps a location of a pickingStation based on init
location(object(pickingStation,P),pair(X,Y),0)	:- init(object(pickingStation,P),value(at,pair(X,Y))).
object(pickingStation,P)						:- init(object(pickingStation,P),value(at,pair(X,Y))).

% Maps a location of a robot based on init
location(object(robot,R),pair(X,Y),0)	:- init(object(robot,R),value(at,pair(X,Y))).
object(robot,R) 						:- init(object(robot,R),value(at,pair(X,Y))).

% Extracts the shelf objects and their locations
location(object(shelf,S),pair(X,Y),0)	:- init(object(shelf,S),value(at,pair(X,Y))).
object(shelf,S) 						:- init(object(shelf,S),value(at,pair(X,Y))).

% Extracts the product objects and their locations
on(object(product,I),object(shelf,S),U,0)	:- init(object(product,I),value(on,pair(S,U))).
object(product,I) 							:- init(object(product,I),value(on,pair(S,U))).

% Extracts the order objects and their locations
object(order,O) 									:- init(object(order,O),value(line,pair(I,U))).
value(line,pair(I,U))								:- init(object(order,O),value(line,pair(I,U))).
object(order,O,value(line,pair(I,U)))               :- init(object(order,O),value(line,pair(I,U))).

object(order,O) 										:- init(object(order,O),value(pickingStation,P)).
object(pickingStation,P)								:- init(object(order,O),value(pickingStation,P)).
object(order,O,value(pickingStation,P))                 :- init(object(order,O),value(pickingStation,P)).

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% GOAL STATE DERIVED FROM INITIAL INSTANCE
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% I count the number of deliveries that need to be fulfilled and place it in this predicate needed_deliveries(C,T)
% I then also set it so that the goal is you want needed_deliveries to have  a zero value at time step m. 
needed_deliveries(C,0) :- C = #count{O,I,U : object(order,O, value(line,pair(I,U)))}.
:- not needed_deliveries(0,m).

%#show value/2.

%#show location/2.
%#show on/4.
%#show object/3.
%#show needed_deliveries/2.