% Dinko Korunic, kreator@srk.fer.hr
% Tue Jan 22 13:55:09 CET 2002
% vim: set syntax=off:ts=2:sw=2:

:- module(percept,[
  percept_create/6, 
  percept_print/1, 
  percept_stench/1,
  percept_breeze/1,
  percept_glitter/1, 
  percept_bump/1,
  percept_scream/1]).

:-use_module('world.pl').

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% creation
percept_create(World,I,J,Bump,Scream,Percept):-
  world_get_symbols(P,WA,WD,G,A),
	percept_check(World,I,J,WA,stench,[],P1),
	percept_check(World,I,J,P,breeze,P1,P2),
	percept_check_gold(World,I,J,G,P2,P3),
	percept_check(Bump,bump,P3,P4),
	percept_check(Scream,scream,P4,Percept).

% provjera "vanjskih" podrazaja kao bump i scream
percept_check(B,X,Percept,Percept1):-
	B==yes,
	select(X,Percept1,Percept),!;
	Percept1=Percept.

% provjera podraza u svijetu
percept_check(World,I,J,X,B,Percept,Percept1):-
	(I1 is I+1,
	world_get(World,I1,J,Lista),
	member(X,Lista);
	I1 is I-1,
	world_get(World,I1,J,Lista),
	member(X,Lista);
	J1 is J+1,
	world_get(World,I,J1,Lista),
	member(X,Lista);
	J1 is J-1,
	world_get(World,I,J1,Lista),
	member(X,Lista)),
	select(B,Percept1,Percept),!;
	Percept1=Percept.

% provjera podrazaja za zlato (X:Y)
percept_check_gold(World,I,J,G,Percept,Percept1):-
	world_get(World,I,J,Lista),
	member(G,Lista),
	select(glitter,Percept1,Percept),!;
	Percept1=Percept.
  
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% operations
percept_stench(P):-
	member(stench,P).
percept_breeze(P):-
	member(breeze,P).
percept_glitter(P):-
	member(glitter,P).
percept_bump(P):-
	member(bump,P).
percept_scream(P):-
	member(scream,P). 
percept_print(P):-
	print(P),
	nl.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% test driver
goal:-
  world_create(W),
  world_print(W),
  between(1,4,I),
  between(1,5,J),
  percept_create(W,I,J,no,no,P),
  write('Perception at ('), write(I:J), write('): '),
  percept_print(P),
  I=4,
  J=5.