(defparameter *congestion-city-nodes* nil)
(defparameter *congestion-city-edges* nil)
(defparameter *visited-nodes* nil)
(defparameter *node-num* 30)
(defparameter *edge-num* 45)
(defparameter *worm-num* 3)
(defparameter *cop-odds* 15)

(defun random-node ()
  (1+ (random *node-num*)))

(defun edge-pair (a b)
  (unless (eql a b)
    (list (cons a b) (cons b a))))

(defun make-edge-list ()
  (apply #'append (loop repeat *edge-num*
                        collect (edge-pair (random-node) (random-node)))))

(defun direct-edges (node edge-list)
  (remove-if-not (lambda (x)
                   (eql (car x) node))
                 edge-list))

(defun get-connected (node edge-list)
  (let ((visited nil))
    (labels ((traverse (node)
               (unless (member node visited)
                 (push node visited)
                 (mapc (lambda (edge)
                         (traverse (cdr edge)))
                       (direct-edges node edge-list)))))
      (traverse node))
    visited))

(defun connect-with-bridges (islands)
  (print islands)
  (when (cdr islands)
    (append (edge-pair (caar islands) (caadr islands))
            (connect-with-bridges (cdr islands)))))

(defun find-islands (nodes edge-list)
  (let ((islands nil))
    (labels ((find-island (nodes)
               (let* ((connected (get-connected (car nodes) edge-list))
                      (unconnected (set-difference nodes connected)))
                 (push connected islands)
                 (when unconnected
                   (find-island unconnected)))))
      (find-island nodes))
    islands))

(defun connect-all-islands (nodes edge-list)
  (append (connect-with-bridges (find-islands nodes edge-list)) edge-list))

(defun edges-to-alist (edge-list)
  (mapcar (lambda (node1)
            (cons node1
                  (mapcar (lambda (edge)
                            (list (cdr edge)))
                          (remove-duplicates (direct-edges node1 edge-list)
                                             :test #'equal))))
          (remove-duplicates (mapcar #'car edge-list))))

(defun add-cops (edge-alist edges-with-cops)
  (mapcar (lambda (x)
            (let ((node1 (car x))
                  (node1-edges (cdr x)))
              (cons node1
                    (mapcar (lambda (edge)
                              (let ((node2 (car edge)))
                                (if (intersection (edge-pair node1 node2)
                                                  edges-with-cops
                                                  :test #'equal)
                                    (list node2 'cops)
                                  edge)))
                            node1-edges))))
          edge-alist))

(defun make-city-edges ()
  (let* ((nodes (loop for i from 1 to *node-num*
                      collect i))
         (edge-list (connect-all-islands nodes (make-edge-list)))
         (cops (remove-if-not (lambda (x)
                                (zerop (random *cop-odds*)))
                              edge-list)))
    (add-cops (edges-to-alist edge-list) cops)))

(defun neighbors (node edge-alist)
  (mapcar #'car (cdr (assoc node edge-alist))))

(defun within-one (a b edge-alist)
  (member b (neighbors a edge-alist)))

(defun within-two (a b edge-alist)
  (or (within-one a b edge-alist)
      (some (lambda (x)
              (within-one x b edge-alist))
            (neighbors a edge-alist))))

(defun make-city-nodes (edge-alist)
  (let ((wumpus (random-node))
        (glow-worms (loop for i below *worm-num*
                          collect (random-node))))
    (loop for n from 1 to *node-num*
          collect (append (list n)
                          (cond ((eql n wumpus) '(wumpus))
                                ((within-two n wumpus edge-alist) '(blood!)))
                          (cond ((member n glow-worms)
                                 '(glow-worm))
                                ((some (lambda (worm)
                                         (within-one n worm edge-alist))
                                       glow-worms)
                                 '(lights!)))
                          (when (some #'cdr (cdr (assoc n edge-alist)))
                            '(sirens!))))))

(defun new-game ()
  (setf *congestion-city-edges* (make-city-edges))
  (setf *congestion-city-nodes* (make-city-nodes *congestion-city-edges*))
  (setf *player-pos* (find-empty-node))
  (setf *visited-nodes* (list *player-pos*))
  (draw-city))

(defun find-empty-node ()
  (let ((x (random-node)))
    (if (cdr (assoc x *congestion-city-nodes*))
        (find-empty-node)
        x)))

(defun draw-city ()
  (ugraph->png "city" *congestion-city-nodes* *congestion-city-edges*))

(defun known-city-nodes ()
  (mapcar (lambda (node)
            (if (member node *visited-nodes*)
                (let ((n (assoc node *congestion-city-nodes*)))
                  (if (eql node *player-pos*)
                      (append n '(*))
                      n))
                (list node '?)))
          (remove-duplicates 
              (append *visited-nodes*
                      (mapcan (lambda (node)
                                (neighbors node *congestion-city-edges*))
                              *visited-nodes*)))))

(defun known-city-edges ()
  (mapcar (lambda (node)
            (cons node (mapcar (lambda (x)
                                 (if (member (car x) *visited-nodes*)
                                     x
                                   (list (car x))))
                                   (cdr (assoc node *congestion-city-edges*)))))
          *visited-nodes*))

(defun draw-known-city ()
  (ugraph->png "known-city" (known-city-nodes) (known-city-edges)))

(defun new-game ()
  (setf *congestion-city-edges* (make-city-edges))
  (setf *congestion-city-nodes* (make-city-nodes *congestion-city-edges*))
  (setf *player-pos* (find-empty-node))
  (setf *visited-nodes* (list *player-pos*))
  (draw-city)
  (draw-known-city))

(defun walk (pos)
  (handle-direction pos nil))

(defun charge (pos)
  (handle-direction pos t))

(defun handle-direction (pos charging)
  (let ((edge (assoc pos 
                     (cdr (assoc *player-pos* *congestion-city-edges*)))))
    (if edge
        (handle-new-place edge pos charging)
      (princ "That location does not exist!"))))

(defun handle-new-place (edge pos charging)
  (let* ((node (assoc pos *congestion-city-nodes*))
         (has-worm (and (member 'glow-worm node)
                        (not (member pos *visited-nodes*)))))
    (pushnew pos *visited-nodes*)
    (setf *player-pos* pos)
    (draw-known-city)
    (cond ((member 'cops edge) (princ "You ran into the cops. Game Over."))
          ((member 'wumpus node) (if charging
                                     (princ "You found the Wumpus!")
                                     (princ "You ran into the Wumpus")))
          (charging (princ "You wasted your last bullet. Game Over."))
          (has-worm (let ((new-pos (random-node)))
                      (princ "You ran into a Glow Worm Gang! You're now at ")
                      (princ new-pos)
                      (handle-new-place nil new-pos nil))))))