Notes

location(T1,R,C) :-
% recursive call of all times player been at such point
% this addition fixes such calls.
% exp: location(T, 1, 1) -> T = 1, T = 3, T = 12...
nonvar(T1), nonvar(R), nonvar(C),
T0 is T1 - 1,
RN is R - 1,
RS is R + 1,
CW is C - 1,
CE is C + 1,
(
((action(T0,eat); action(T0,clockWise); action(T0,counterClockWise)), location(T0, R, C));
((action(T0,attack); action(T0,forward)), bump(T1), location(T0, R, C));
((action(T0,attack); action(T0,forward)), dir(T0,north), not(bump(T1)), location(T0, RS, C));
((action(T0,attack); action(T0,forward)), dir(T0,south), not(bump(T1)), location(T0, RN, C));
((action(T0,attack); action(T0,forward)), dir(T0,west), not(bump(T1)), location(T0, R, CE));
((action(T0,attack); action(T0,forward)), dir(T0,east), not(bump(T1)), location(T0, R, CW))
).

dir(T1,north) :-
T0 is T1 - 1,
(
((action(T0,eat);action(T0,attack);action(T0,forward)), dir(T0,north));
(action(T0,clockWise), dir(T0,west));
(action(T0,counterClockWise), dir(T0,east))
).

dir(T1,east) :-
T0 is T1 - 1,
(
((action(T0,eat);action(T0,attack);action(T0,forward)), dir(T0,east));
(action(T0,clockWise), dir(T0,north));
(action(T0,counterClockWise), dir(T0,south))
).

dir(T1,south) :-
T0 is T1 - 1,
(
((action(T0,eat);action(T0,attack);action(T0,forward)), dir(T0,south));
(action(T0,clockWise), dir(T0,east));
(action(T0,counterClockWise), dir(T0,west))
).

dir(T1,west) :-
T0 is T1 - 1,
(
((action(T0,eat);action(T0,attack);action(T0,forward)), dir(T0,west));
(action(T0,clockWise), dir(T0,south));
(action(T0,counterClockWise), dir(T0,north))
).

/**
README
All procedures designed to be time independent which may lower or
increase performance.

Important assumption, there could be no close entities that could
simultaneously cause a "effect" such as enemy, food, or pit.
*/

/* Wall variables related */
isWall(T,R,C) :-
isWall(R,C).
isWall(X,Y):- % change in Q1
(X =:= 0; Y =:= 0);
(CW is Y - 1, location(T,X,CW), dir(T,east), TN is T + 1, bump(TN));
(RN is X - 1, location(T,RN,Y), dir(T,south),TN is T + 1, bump(TN));
(CE is Y + 1, location(T,X,CE), dir(T,west), TN is T + 1, bump(TN));
(RS is X + 1, location(T,RS,Y), dir(T,north),TN is T + 1, bump(TN)).
isClear(T,R,C) :- % change in Q1
hasNotEnemy(T,R,C),
hasNotPit(T,R,C),
not(isWall(R,C)).

% initilization, "no such procedure" fix...
% change this to check existance of a procedure each time...
action(-1,_).
enemySight(-1).
enemySmell(-1).
pitBreeze(-1).
foodSmell(-1).
full(-1).
bump(-1).
isWall(-1,-1).
isWall(-1,-1,-1).

hasNotEnemy(T,R,C) :- % change in Q2
RN is R - 1, RS is R + 1,
CW is C - 1, CE is C + 1,
findall(A, (enemySmell(A), not(A = -1)), ET),
not(
(
hasEverBeenAt(ET,R,CW), !;
hasEverBeenAt(ET,R,CE), !;
hasEverBeenAt(ET,RN,C), !;
hasEverBeenAt(ET,RS,C)
)
).

% helper function to check if player
% ever been at given location in given times.
hasEverBeenAt([],R,C) :- fail.
hasEverBeenAt([H|T],R,C) :-
location(H,R,C), !; hasEverBeenAt(T,R,C).

hasNotPit(T,R,C) :- % change in Q2
RN is R - 1, RS is R + 1,
CW is C - 1, CE is C + 1,
findall(A, (pitBreeze(A), not(A = -1)), PT),
not(
(
hasEverBeenAt(PT,R,CW), !;
hasEverBeenAt(PT,R,CE), !;
hasEverBeenAt(PT,RN,C), !;
hasEverBeenAt(PT,RS,C)
)
).

% assumes there are no pit close by that can cause breeze
hasPit(T,R,C) :- % change in Q3
RN is R - 1, RS is R + 1,
CW is C - 1, CE is C + 1,
findall(A,(pitBreeze(A), not(A = -1)),PT),
(
(hasEverBeenAt(PT,R,CW), hasEverBeenAt(PT,R,CE)), !;
(hasEverBeenAt(PT,R,CW), hasEverBeenAt(PT,RN,C)), !;
(hasEverBeenAt(PT,R,CW), hasEverBeenAt(PT,RS,C)), !;
(hasEverBeenAt(PT,R,CE), hasEverBeenAt(PT,RN,C)), !;
(hasEverBeenAt(PT,R,CE), hasEverBeenAt(PT,RS,C)), !;
(hasEverBeenAt(PT,RN,C), hasEverBeenAt(PT,RS,C))
).

% helper procedure to hasEnemy,
% if agent have seen the enemy and felt the smell
% then there definitely is a enemy
hasEnemySighted(R,C) :-
enemySight(T), not(T = -1),
location(T,SR,SC),
( % If anything has been spoted
(SR = R, ((SC =< C, dir(T,east ));(SC >= C, dir(T,west )))), !;
(SC = C, ((SR =< R, dir(T,south));(SR >= R, dir(T,north))))
),
RN is R - 1, RS is R + 1,
CW is C - 1, CE is C + 1,
findall(A,(enemySmell(A),not(A = -1)),PT),
( % If there were any smell around, then there is a enemy
hasEverBeenAt(PT,R,CW), !;
hasEverBeenAt(PT,R,CE), !;
hasEverBeenAt(PT,RN,C), !;
hasEverBeenAt(PT,RS,C)
).

% If enemy has not seen in location of question
% assumes there are no enemy close by that can cause smell
hasEnemy(T,R,C) :- % change in Q3
RN is R - 1, RS is R + 1,
CW is C - 1, CE is C + 1,
findall(A,(enemySmell(A),not(A = -1)),PT),
% There was an enemy sight in R,C
(hasEnemySighted(R,C), !;
( % If there is breeze in more than one neighbor, then there is a pit
(hasEverBeenAt(PT,R,CW), hasEverBeenAt(PT,R,CE)), !;
(hasEverBeenAt(PT,R,CW), hasEverBeenAt(PT,RN,C)), !;
(hasEverBeenAt(PT,R,CW), hasEverBeenAt(PT,RS,C)), !;
(hasEverBeenAt(PT,R,CE), hasEverBeenAt(PT,RN,C)), !;
(hasEverBeenAt(PT,R,CE), hasEverBeenAt(PT,RS,C)), !;
(hasEverBeenAt(PT,RN,C), hasEverBeenAt(PT,RS,C))
)
).
% Assumes agent only attack to kill.
hasDeadEnemy(T,R,C) :- % change in Q3
action(T1,attack), not(T1 = -1),
location(T1,AR,AC),
(
(AR = R, ((AC =:= (C - 1), dir(T1,east ));(AC =:= (C + 1), dir(T1,west )))), !;
(AC = C, ((AR =:= (R - 1), dir(T1,south));(AR =:= (R + 1), dir(T1,north))))
).

% helper function to check if player
% ever been at given location in given times.
doesContain([],R,C) :- fail.
doesContain([[RH|CH]|T],R,C) :-
(RH =:= R, CH =:= C), !; doesContain(T,R,C).

hasFood(T,R,C) :- % change in Q4
% check if any food has been eaten in given location.
findall([FLR,FLC], (full(A), not(A = -1), location(A,FLR,FLC)), FLT),
not(doesContain(FLT,R,C)),
% if there were any food smell around,
% then tell hasFood to force agent to try eat action.
findall(A,
(
foodSmell(A), not(A = -1),
% weed out smells around eaten foods.
location(A,SR,SC), not(doesContain(FLT,SR,SC))
),FT),
RN is R - 1, RS is R + 1,
CW is C - 1, CE is C + 1,
(
hasEverBeenAt(FT,R,CW), !;
hasEverBeenAt(FT,R,CE), !;
hasEverBeenAt(FT,RN,C), !;
hasEverBeenAt(FT,RS,C)
).

hasNotFood(T,R,C) :- % change in Q4
% if a food has eaten here, assert true immediately
findall([FLR,FLC], (full(A), not(A = -1), location(A,FLR,FLC)), FLT),
doesContain(FLT,R,C), !;

RN is R - 1, RS is R + 1,
CW is C - 1, CE is C + 1,
findall(A,(foodSmell(A),not(A = -1)),FT),
% If there were not any smell around
not(hasEverBeenAt(FT,R,CW)),
not(hasEverBeenAt(FT,R,CE)),
not(hasEverBeenAt(FT,RN,C)),
not(hasEverBeenAt(FT,RS,C)).