;;; tests.lisp --- Q Tests

 ;; 

 ;;; Code:

 (in-package :q/tests)

 (defsuite :q)

 (in-suite :q)

 (deftest sanity ()

   (is (make-instance 'query-engine

         :parser (make-instance 'query-parser)

         :optimizer (make-instance 'sql-optimizer)

         :sources nil)))

 (deftest sql-select ()

   (setf (gethash "FOO" tbl) (make-df nil))

   (with-sql (expr "SELECT I FROM FOO")

     (is (typep expr 'sql-select))

     (let ((tbl (make-hash-table :test 'equalp)))

       (is (gethash "FOO" tbl))

       (make-sql-data-frame expr tbl))))

 (deftest sql-math ()

   (with-sql (expr "1 + 2 * 3")

     (is (typep expr 'sql-math-expression))

     (is (typep (rhs expr) 'sql-math-expression))

     (is (typep (lhs expr) 'sql-number))))

 ;; https://www.cpp.edu/~jrfisher/www/prolog_tutorial/2_1.html

 (deftest dql (:skip t)

   (adjacent 1 2)

   (adjacent 2 1) 

   (adjacent 1 3)

   (adjacent 3 1) 

   (adjacent 1 4)

   (adjacent 4 1) 

   (adjacent 1 5)

   (adjacent 5 1) 

   (adjacent 2 3)

   (adjacent 3 2) 

   (adjacent 2 4)

   (adjacent 4 2) 

   (adjacent 3 4)

   (adjacent 4 3) 

   (adjacent 4 5)

   (adjacent 5 4) 

   (color 1 red a)

   (color 1 red b) 

   (color 2 blue a)

   (color 2 blue b) 

   (color 3 green a)

   (color 3 green b) 

   (color 4 yellow a)

   (color 4 blue b) 

   (color 5 blue a)

   (color 5 green b))

 #| SL

 Exercise 2.9. Translate to clausal logic:

 (a) every mouse has a tail;

 (b) somebody loves everybody;

 (c) every two numbers have a maximum.

 |#

 (deftest dql-clausal-simple (:skip t))

 ;; ref: https://en.wikipedia.org/wiki/Zebra_Puzzle

 ;; ref: https://franz.com/support/documentation/11.0/prolog.html

 (deftest dql-zebra ()

   "A solution for the Zebra problem using DQL."

   (<-- (nextto ?x ?y ?list) (iright ?x ?y ?list))

   (<-  (nextto ?x ?y ?list) (iright ?y ?x ?list))

   (<-- (iright ?left ?right (?left ?right . ?rest)))

   (<-  (iright ?left ?right (?x . ?rest))

        (iright ?left ?right ?rest))

   (<-- (zebra ?h ?w ?z)

        ;; Each house is of the form:

        ;; (house nationality pet cigarette drink house-color)

        (= ?h ((house norwegian ? ? ? ?)   ;1,10

               ?

               (house ? ? ? milk ?) ? ?))  ; 9

        (member (house englishman ? ? ? red) ?h) ; 2

        (member (house spaniard dog ? ? ?) ?h) ; 3

        (member (house ? ? ? coffee green) ?h) ; 4

        (member (house ukrainian ? ? tea ?) ?h) ; 5

        (iright (house ? ? ? ? ivory)      ; 6

                (house ? ? ? ? green) ?h)

        (member (house ? snails winston ? ?) ?h) ; 7

        (member (house ? ? kools ? yellow) ?h) ; 8

        (nextto (house ? ? chesterfield ? ?) ;11

                (house ? fox ? ? ?) ?h)

        (nextto (house ? ? kools ? ?)      ;12

                (house ? horse ? ? ?) ?h)

        (member (house ? ? luckystrike oj ?) ?h) ;13

        (member (house japanese ? parliaments ? ?) ?h) ;14

        (nextto (house norwegian ? ? ? ?)  ;15

                (house ? ? ? ? blue) ?h)

        (member (house ?w ? ? water ?) ?h) ;Q1

        (member (house ?z zebra ? ? ?) ?h)) ;Q2

   ;; execute the query

   (?- (zebra ?houses ?water-drinker ?zebra-owner))

   ;; It is believed that solving zebra a

   ;; single time requires 12825 inferences.

   )