;;; -*- Mode: LISP; Syntax: Common-lisp; Package: sipe-cl; Base: 10; -*-

(in-package :sipe)
;AUTHORS: Carla O. Ludlow and Karen M. Alguire and David E. Wilkins
(setq *domain-name* 'Missionaries-and-Cannibals)

(setq *DEFAULT-DEPTH-LIMIT* 14) ;extend default depth limit

(DEFINE.DOMAIN)
CLASS: river-banks
INSTANCES: left-bank, right-bank
END CLASS

CLASS: people
INSTANCES: cannibals, missionaries
END CLASS

CLASS: boats
INSTANCES: two-people-boat
END CLASS

STOP

(DEFINE.DOMAIN)
static-predicates: (opposite-bank)

PREDICATES:
(opposite-bank left-bank right-bank)
(opposite-bank right-bank left-bank)
 
(state  3 3 0 0 left-bank)
;prevent the return to identical states, eg identical return trip

(on two-people-boat left-bank)

(level cannibals left-bank 3)
(level cannibals right-bank 0)
(level missionaries left-bank 3)
(level missionaries right-bank 0)

END PREDICATES
STOP

(DEFINE.DOMAIN)

;;==============================OPERATORS==============================
;;; These 2 operators instigate trips by (1)  ordering of operators
;;   (prefer 2 people when moving to goal, 1 person on return trips), and
;;   (2) computing numerical values of state for use in move oprs.

OPERATOR: SEND-TRIP-TO-RIGHT
ARGUMENTS: continuous1, numerical1 is previous value of continuous1,
           continuous2, numerical2 is previous value of continuous2,
           continuous3, numerical3 is previous value of continuous3,
           continuous4, numerical4 is previous value of continuous4;
PURPOSE: (move-everybody)
PRECONDITION: (on two-people-boat left-bank)
	      (level cannibals left-bank continuous1)
              (level cannibals right-bank continuous2)
              (level missionaries left-bank continuous3)
              (level missionaries right-bank continuous4);
PLOT: 
    CHOICEPROCESS: 
      ACTION: move-mc, move-2-c, move-2-m, move-1-c, move-1-m;
      ARGUMENTS: numerical1,numerical3,numerical2,numerical4,right-bank;
      EFFECTS: (on two-people-boat right-bank);
    GOAL:   (move-everybody)
END PLOT END OPERATOR 
 

OPERATOR: SEND-TRIP-TO-LEFT
ARGUMENTS: continuous1, numerical1 is previous value of continuous1,
           continuous2, numerical2 is previous value of continuous2,
           continuous3, numerical3 is previous value of continuous3,
           continuous4, numerical4 is previous value of continuous4;
PURPOSE:  (move-everybody);
PRECONDITION: (on two-people-boat right-bank)
	      (level cannibals left-bank continuous1)
              (level cannibals right-bank continuous2)
              (level missionaries left-bank continuous3)
              (level missionaries right-bank continuous4);
PLOT: 
    CHOICEPROCESS: 
      ACTION: end-mc,  move-1-m, move-1-c, move-mc, move-2-c, move-2-m;
      ARGUMENTS: numerical2,numerical4,numerical1,numerical3,left-bank;
      EFFECTS: (on two-people-boat left-bank);
    GOAL:   (move-everybody)
END PLOT END OPERATOR


OPERATOR: END-MC
ARGUMENTS: numerical1, numerical2, numerical3, numerical4, river-bank1;
PRECONDITION: (level missionaries left-bank 0)
              (level cannibals left-bank 0);
PLOT: 
    PROCESS ACTION: no-human-stew
            EFFECTS: (move-everybody);
END PLOT END OPERATOR 



;;================================= Move Operators =================

OPERATOR: MOVE-MC
ARGUMENTS: numerical3, numerical4, numerical1, numerical2, river-bank1,
           numerical5 is (sipe+ 1 numerical1),
           numerical6 is  (sipe+ 1 numerical2),
           numerical7 is (sipe+ -1 numerical3), 
           numerical8 is  (sipe+ -1 numerical4),  river-bank2;
PRECONDITION: (opposite-bank river-bank1 river-bank2) 
          (not (state numerical5 numerical6 numerical7 numerical8 river-bank1))
          (level>= cannibals river-bank2 1)
          (level>= missionaries river-bank2 1)
          (or (level missionaries river-bank2 1)
              (level<= numerical7 numerical8))
          (level<= numerical5 numerical6);
PLOT: 
    PROCESS
	ACTION: row-mc
        ARGUMENTS:  numerical3, numerical4, numerical1, numerical2, river-bank1;
        EFFECTS: (on two-people-boat river-bank1) 
                 (produce cannibals river-bank1 1)
                 (produce missionaries river-bank1 1)
                 (state numerical5 numerical6 numerical7 numerical8 river-bank1);
END PLOT END OPERATOR 

OPERATOR: MOVE-2-C
ARGUMENTS: numerical3, numerical4, numerical1, numerical2, river-bank1,
           numerical5 is (sipe+ -2 numerical3), 
           numerical6 is  (sipe+ 2 numerical1),
           numerical7 is (sipe+ 0  numerical4), 
           numerical8 is  (sipe+ 0  numerical2), river-bank2 ;
PRECONDITION: (opposite-bank river-bank1 river-bank2) 
          (not (state numerical6 numerical8 numerical5 numerical7 river-bank1))
          (level>= cannibals river-bank2 2)
          (or (level missionaries river-bank1 0)
              (level>=  missionaries river-bank1 numerical6));
PLOT: 
    PROCESS
	ACTION: row-2-c
        ARGUMENTS:  numerical3, numerical4, numerical1, numerical2, river-bank1;
        EFFECTS: (on two-people-boat river-bank1) 
                 (produce cannibals river-bank1 2)
                 (state numerical6 numerical8 numerical5 numerical7 river-bank1);
END PLOT END OPERATOR 

OPERATOR: MOVE-1-C
ARGUMENTS: numerical3, numerical4, numerical1, numerical2, river-bank1,
           numerical5 is (sipe+ -1 numerical3), 
           numerical6 is  (sipe+ 1 numerical1), 
           numerical7 is (sipe+ 0  numerical4), 
           numerical8 is  (sipe+ 0  numerical2),river-bank2;
PRECONDITION: (opposite-bank river-bank1 river-bank2)
          (not (state numerical6 numerical8 numerical5 numerical7 river-bank1))
          (level>= cannibals river-bank2 1)
          (or (level missionaries river-bank1 0)
              (level>=  missionaries river-bank1 numerical6));
PLOT: 
    PROCESS
	ACTION: row-1-c
        ARGUMENTS:  numerical3, numerical4, numerical1, numerical2, river-bank1;
        EFFECTS: (on two-people-boat river-bank1) 
                 (produce cannibals river-bank1 1)
                 (state numerical6 numerical8 numerical5 numerical7 river-bank1);
END PLOT END OPERATOR 


OPERATOR: MOVE-2-M
ARGUMENTS: numerical3, numerical4, numerical1, numerical2, river-bank1,
           numerical5 is (sipe+ -2 numerical4), 
           numerical6 is  (sipe+ 2 numerical2), 
           numerical7 is  (sipe+ 0 Numerical3),
           numerical8 is (sipe+ 0 numerical1), river-bank2 ;
PRECONDITION: (opposite-bank river-bank1 river-bank2)
          (not (state numerical8 numerical6 numerical7 numerical5 river-bank1))
          (level>= missionaries river-bank2 2)
          (or (level missionaries river-bank2 2)
              (level<=  cannibals river-bank2 numerical5)),
          (level<=  cannibals river-bank1 numerical6);
PLOT: 
    PROCESS
	ACTION: row-2-m
        ARGUMENTS:  numerical3, numerical4, numerical1, numerical2, river-bank1;
        EFFECTS: (on two-people-boat river-bank1) 
                 (produce missionaries river-bank1 2)
                 (state numerical8 numerical6 numerical7 numerical5 river-bank1);
END PLOT END OPERATOR 

OPERATOR: MOVE-1-M
ARGUMENTS: numerical3, numerical4, numerical1, numerical2, river-bank1,
           numerical5 is (sipe+ -1 numerical4), 
           numerical6 is  (sipe+ 1 numerical2),
           numerical7 is  (sipe+ 0 numerical3),
           numerical8 is (sipe+ 0 numerical1), river-bank2;
PRECONDITION: (opposite-bank river-bank1 river-bank2)
          (not (state numerical8 numerical6 numerical7 numerical5 river-bank1))
          (level>= missionaries river-bank2 1)
          (or (level missionaries river-bank2 1)
              (level<=  cannibals river-bank2 numerical5)),
          (level<=  cannibals river-bank1 numerical6);
PLOT: 
    PROCESS
	ACTION: row-1-m
        ARGUMENTS:  numerical3, numerical4, numerical1, numerical2, river-bank1;
        EFFECTS: (on two-people-boat river-bank1) 
                 (produce missionaries river-bank1 1)
                 (state numerical8 numerical6 numerical7 numerical5 river-bank1);
END PLOT END OPERATOR 



;;========================== Causal Theory ============================

CAUSAL-RULE: ON-BANK-NOT-ON-OTHER-BANK
ARGUMENTS: boat1, river-bank1, river-bank2;
TRIGGER: (on boat1 river-bank1);
PRECONDITION: (on boat1 river-bank2) (opposite-bank river-bank1 river-bank2);
EFFECTS: (not (on boat1 river-bank2));
END CAUSAL-RULE

CAUSAL-RULE: PRODUCE-AND-CONSUME-CANNIBALS
ARGUMENTS: cannibals, river-bank1, numerical3, river-bank2;
TRIGGER: (produce cannibals river-bank1 numerical3);
PRECONDITION: (opposite-bank river-bank1 river-bank2)
EFFECTS: (consume cannibals  river-bank2 numerical3);
END CAUSAL-RULE

CAUSAL-RULE: PRODUCE-AND-CONSUME-MISSIONARYS
ARGUMENTS: missionaries, river-bank1, numerical3, river-bank2;
TRIGGER: (produce missionaries river-bank1 numerical3);
PRECONDITION: (opposite-bank river-bank1 river-bank2)
EFFECTS: (consume missionaries  river-bank2 numerical3);
END CAUSAL-RULE

STOP

;;========================= Problem ==========================


(DEFINE.PROBLEM)

PROBLEM: move-3-of-each
        Goal: (move-everybody)
END PROBLEM


STOP


;; ==========  Customizes plan printing to use English-like phrases

(setq name-flag :text-description args-flag nil)

(setq *ACTION-DOCUMENTATION-STRINGS*
      '((row-1-m (5) "Row 1 missionary~% to ~A")
	(row-2-m (5) "Row 2 missionaries~% to ~A")
	(row-2-c (5) "Row 2 cannibals~% to ~A")
	(row-1-c (5) "Row 1 cannibal~% to ~A")
	(row-mc (5) "Row 1 cannibal and 1 missionary~% to ~A") ))

(setq *DOCUMENTATION-STRINGS*
      '((move-everybody nil "Move everybody on the left-bank~% to the right-bank")))