Add food management

server/game.lisp

@@ -11,7 +11,12 @@
     :accessor snake)
    (dir
     :initarg :initial-direction
-    :initform :right)))
+    :initform :right)
+   (grid-size
+    :initarg :grid-size
+    :initform (list 30 30))
+   (food
+    :initform (make-array 0))))
 
 ;;; Class constructor to initialize the snake
 (defmethod initialize-instance :after ((g game) &key)
@@ -20,7 +25,7 @@
 
 ;;; Pretty-print a game
 (defmethod print-object ((g game) stream)
-  (with-slots (snake dir) g
+  (with-slots (snake dir food) g
     (format t "Snake:      ")
     (dotimes (i (first (array-dimensions snake)))
       (let ((elem (aref snake i)))
@@ -28,7 +33,11 @@
           (format t "<="))
         (format t "(~a,~a)" (first elem) (second elem))))
     (format t "~%Size:       ~a" (first (array-dimensions snake)))
-    (format t "~%Direction:  ~a" dir)))
+    (format t "~%Direction:  ~a" dir)
+    (format t "~%Food:  ~a" food)))
+
+(defgeneric add-food (g nb)
+  (:documentation "Add food on the game grid."))
 
 (defgeneric refresh (g &key)
   (:documentation "Refresh the game g (move forward or change direction)."))
@@ -86,3 +95,16 @@
               
   ;; Check if we loose
   )
+
+(defmethod add-food ((g game) nb)
+  (with-slots (snake grid-size food) g
+    (let ((snake-list (coerce snake 'list)) ; To be able to use the function member later
+          (food-list (coerce food 'list))
+          (size-x (first grid-size))
+          (size-y (second grid-size))
+          (food-size (first (array-dimensions food))))
+      (dotimes (i nb)
+        (let ((x (random size-x))
+              (y (random size-y)))
+          (when (eq (member (list x y) snake-list) nil) ; Add if there is no conflict between snake and food position
+            (setf food (make-array (1+ food-size) :initial-contents `(,@food-list ,(list x y))))))))))