% File: crypto.pro of directory xsolve1
% Type: Prolog source
% Line: cryptores.pro
% Date: Fall 2009

%----------------------------------------------------------------------
% load some files

:- consult('combosets.pro').
:- consult('gv.pro').

crypto(N1,N2,Goal,ex(N1,+,N2)) :- Goal is (N1 + N2).
crypto(N1,N2,Goal,ex(N1,*,N2)) :- Goal is (N1 * N2).
crypto(N1,N2,Goal,ex(N1,-,N2)) :- Goal is (N1 - N2).
crypto(N1,N2,Goal,ex(N1,-,N2)) :- Goal is (N2 - N1).
crypto(N1,N2,Goal,ex(N1,/,N2)) :- N2 > 0, Goal is (N1 / N2).
crypto(N1,N2,Goal,ex(N1,/,N2)) :- N1 > 0, Goal is (N2 / N1).

crypto(N1,N2,N3,G,Expr) :-
  combos(set(N1,N2,N3), combo(A,B), extra(C)),
  crypto(A,B,SG,SGE),
  crypto(C,SG,G,UGE),
  substitute(SGE,SG,UGE,Expr).

crypto(N1,N2,N3,N4,G,Expr) :-
  combos(set(N1,N2,N3,N4), combo(A,B), extras(C,D)),
  crypto(A,B,SG,SGE),
  crypto(C,D,SG,G,UGE),
  substitute(SGE,SG,UGE,Expr).

crypto(N1,N2,N3,N4,N5,G,Expr) :-
  combos(set(N1,N2,N3,N4,N5), combo(A,B), extras(C,D,E)),
  crypto(A,B,SG,SGE),
  crypto(C,D,E,SG,G,UGE),
  substitute(SGE,SG,UGE,Expr).


%----------------------------------------------------------------------
% key substitution code

substitute(New,Old,ex(Old,O,Z), ex(New,O,Z)).
substitute(New,Old,ex(X,O,Old), ex(X,O,New)).
substitute(New,Old,ex(X,O,Z), ex(Q,O,Z)) :-
  substitute(New,Old,X,Q).
substitute(New,Old,ex(X,O,Z), ex(X,O,Q)) :- 
  substitute(New,Old,Z,Q).

%----------------------------------------------------------------------
% random crypto prob

establishCryptoProblemParameters :-
  declare(lo,0),
  declare(hi,15).

generateRandomCryptoNumber(N) :-
  valueOf(lo,Lo),
  valueOf(hi,Hi),
  Hip is Hi + 1,
  random(Lo,Hip,N).

generateRandomCryptoProblem :-
  generateRandomCryptoNumber(N1),
  generateRandomCryptoNumber(N2),
  generateRandomCryptoNumber(N3),
  generateRandomCryptoNumber(N4),
  generateRandomCryptoNumber(N5),
  generateRandomCryptoNumber(G),
  addProblemToKB(N1,N2,N3,N4,N5,G).

addProblemToKB(N1,N2,N3,N4,N5,G) :-
  retract(problem(_,_)),
  assert(problem(numbers(N1,N2,N3,N4,N5),goal(G))).

addProblemToKB(N1,N2,N3,N4,N5,G) :-
  assert(problem(numbers(N1,N2,N3,N4,N5),goal(G))).
  
internalizeProblem :-
  problem(numbers(N1,N2,N3,N4,N5),goal(G)),
  eraseProblemBindings,
  eraseProblem,
  eraseSolution,	
  assert(problem(numbers(N1,N2,N3,N4,N5),goal(G))),
  assert(binding(n1,N1)),
  assert(binding(n2,N2)),
  assert(binding(n3,N3)),
  assert(binding(n4,N4)),
  assert(binding(n5,N5)),
  assert(binding(g,G)).
  
eraseProblem :-
  retract(problem(_,_)),
  fail.
eraseProblem.

eraseSolution :-
  retract(solution(_)),
  fail.
eraseSolution.

eraseProblemBindings :-
  retract(binding(n1,_)),
  retract(binding(n2,_)),
  retract(binding(n3,_)),
  retract(binding(n4,_)),
  retract(binding(n5,_)),
  retract(binding(g,_)),
  fail.
eraseProblemBindings.

solveProblemDecomp :-
  problem(numbers(N1,N2,N3,N4,N5),goal(G)),
  crypto(N1,N2,N3,N4,N5,G,Exp),
  assert(solution(Exp)).
  
displaySolution :-
  write('Solution: '),
  solution(S),
  displayResult(S),
  nl.
displaySolution.

displayResult(ex(A,O,B)) :-
  number(A),number(B),
  write('('),write(A),write(' '),write(O),write(' '),write(B),write(' )').
displayResult(ex(A,O,B)) :-
  number(A), B = ex(A1,O1,B1),
  write('( '),write(A),write(' '),write(O),write(' '),
  displayResult(ex(A1,O1,B1)),write(' )').
displayResult(ex(A,O,B)) :-
  number(B), A = ex(A1,O1,B1),
  write('( '),displayResult(ex(A1,O1,B1)),write(' '),write(O),write(' '),
  write(B),write(' )').
displayResult(ex(A,O,B)) :-
  A = ex(A1,O1,B1), B=ex(A2,O2,B2),
  write('( '),displayResult(ex(A1,O1,B1)),write(' '),write(O),write(' '),
  displayResult(ex(A2,O2,B2)),write(' )').
  

displayProblem :-
  problem(numbers(N1,N2,N3,N4,N5),goal(G)),
    write('Problem: numbers = {'),
    write(N1),write(','),
    write(N2),write(','),
    write(N3),write(','),
    write(N4),write(','),
    write(N5),write('} and goal = '),
    write(G),nl.
	
demo :-
    generateRandomCryptoProblem,
	internalizeProblem,
	displayProblem,
	solveProblemDecomp,
	displaySolution.


genprob :-
  establishCryptoProblemParameters,generateRandomCryptoProblem,
  displayProblem.
  
:- establishCryptoProblemParameters.