(defpackage :flappy-ball
  (:use :cl :sketch)
  (:export :flappy-ball :on-click :on-key :setup))

(in-package :flappy-ball)

(defsketch flappy-ball
    ((title "Flappy Ball")
     (width 800)
     (height 600)
     (copy-pixels nil)
     (ball (list (/ width 10) (/ height 3) 0))
     (gravity 0.05)
     (flap-speed -2.5)
     (ball-pen (make-pen :stroke (gray 0.5) :fill sketch:+yellow+ :weight 1))
     (pipe-pen (make-pen :stroke (gray 0.5) :fill sketch:+green+ :weight 1))
     (pipes '((200 200 100) (400 300 100) (600 400 100)))
     (scroll-x 0.0)
     (scroll-speed 0.2))
  
  (flet ((move (b)
           (list
            (car b)
            (alexandria:clamp (+ (cadr b) (caddr b)) 10 (- height 10))
            (+ (caddr b) gravity)))) 
    (with-pen ball-pen
      (circle (car ball) (cadr ball) 10))
    (with-pen pipe-pen
      (dolist (pipe pipes)
        (let ((x (- (car pipe) scroll-x))
              (h (cadr pipe))
              (gap (caddr pipe)))
          (rect x 0 20 h)
          (rect x (+ h gap) 20 (- height h gap)))))
    (setf scroll-x (+ scroll-x scroll-speed))
    (setf ball (move ball)))
  )

(defmethod on-click ((instance flappy-ball) x y)
  (with-slots (ball flap-speed) instance
    (setf (caddr ball) flap-speed)))

(defmethod on-key ((instance flappy-ball) key state)
  (with-slots (ball flap-speed) instance
    (setf (caddr ball) flap-speed)))

(defmethod setup ((instance flappy-ball) &key &allow-other-keys)
  (background (gray 1)))