#lang racket
;--------------------------------- IMPORT FUNCTIONS
(require 2htdp/universe)
(require 2htdp/image)
(require lang/posn)

;---------------------------------- DATA DEFINITIONS

(define-struct cell (x y direction))
(define-struct tail_cell (x y cell))
(define-struct fruit (x y))
(define-struct tail (list tail_cell))
(define-struct snake (cell))
(define-struct data (colides alive WIDTH HEIGHT SCORE snake speed fruit screen))


;----------------------------------DEFINE GETTERS AND SETTERS

;----------------------------------GETTERS
(define (get_x world)
  (cell-x (snake-cell (data-snake world))))
(define (get_y world)
  (cell-y (snake-cell (data-snake world))))
(define (get_fruit_x world)
  (fruit-x (data-fruit world)))
(define (get_fruit_y world)
  (fruit-y (data-fruit world)))
(define (get_colides world)
  (data-colides world))
(define (get_alive world)
  (data-alive world))
(define (screen_width world)
  (data-WIDTH world))
(define (screen_height world)
  (data-HEIGHT world))
(define (get_score world)
  (data-SCORE world))
(define (get_speed world)
  (data-speed world))
(define (get_fruit world)
  (data-fruit world))
(define (get_head world)
  (snake-cell (data-snake world)))
(define (get_direction world)
  (cell-direction (snake-cell (data-snake world))))
(define (get_snake world)
  (data-snake world))

;--------------------------------SETTERS

; x = x pos / y =  y pos / c = cell
(define (set_cell x y d c)
  (make-cell (+ (cell-x c) x) (+ (cell-y c) y) d))

;world = data / i = number to change
(define (make_snake world x y c)
  (make-snake (set_cell x y c (get_head world))))

(define (set_x world i)
  (make-data (get_colides world) (get_alive world) (screen_width world) (screen_height world) (get_score world)
             (make_snake world i 0 (get_direction world))
             (get_speed world) (get_fruit world) (data-screen world)))

(define (set_y world i)
  (make-data (get_colides world) (get_alive world) (screen_width world) (screen_height world) (get_score world)
             (make_snake world 0 i (get_direction world))
             (get_speed world) (get_fruit world) (data-screen world)))

(define (get_data world)
  (make-data (get_colides world) (get_alive world) (screen_width world) (screen_height world) (get_score world)
             (get_snake world)
             (get_speed world) (get_fruit world) (data-screen world)))

(define (set_colides world i)
  (make-data i (get_alive world) (screen_width world) (screen_height world) (get_score world)
             (get_snake world)
             (get_speed world) (get_fruit world) (data-screen world)))

(define (fruit_random world)
  (make-data (get_colides world) (get_alive world) (screen_width world) (screen_height world) (get_score world)
             (get_snake world)
             (get_speed world) (make-fruit (random (screen_width world)) (random (screen_height world))) (data-screen world)))

(define (set_direction world i)
  (make-data (get_colides world) (get_alive world) (screen_width world) (screen_height world) (get_score world)
             (make_snake world 0 0 i)
             (get_speed world) (get_fruit world) (data-screen world)))
(define (make_new_data)
  (make-data #t #t 800 600 0 (make-snake (make-cell 400 300 6)) 6 (make-fruit (random 800) (random 600))
                (rectangle 800 600 "solid" "black")))


;----------------------------------MATH
; i value to add to position to check if is inside boundaries
(define (x_inside world i)
  (and (> (- (get_x world) i) 0) (< (+ (get_x world) i) (screen_width world))))
(define (y_inside world i)
  (and (> (- (get_y world) i) 0) (< (+ (get_y world) i) (screen_height world))))

;-*************************************************************************** THIS IS THE CODE THAT DOESNT WORK
; every condition of the and works when use in isolation, but when uncomented more than one, it doesnt work
(define (inside_fruit world)
  (and
   ;(> (- (get_fruit_x world) 32) (get_x world))
   ;(< (+ (get_fruit_x world) 32) (get_x world))
   ;(> (- (get_fruit_y world) 32) (get_y world))
   ;(< (+ (get_fruit_y world) 32) (get_y world))
   ))

; ----------------------------------- START OF CODE


(define (draw world)
  (
   place-images
   (list (square 32 "solid" "white")
         (square 32 "solid" "blue"))
   (list (make-posn (get_x world) (get_y world))
         (make-posn (get_fruit_x world) (get_fruit_y world)))
   (data-screen world)
  ))


(define (tick_snake world)
  (
   cond
   [(= 6 (get_direction world)) (if (x_inside world (get_speed world)) (set_x world (get_speed world)) (get_data world))]
   [(= 4 (get_direction world)) (if (x_inside world (get_speed world)) (set_x world (- (get_speed world))) (get_data world))]
   [(= 8 (get_direction world)) (if (y_inside world (get_speed world)) (set_y world (get_speed world)) (get_data world))]
   [(= 2 (get_direction world)) (if (y_inside world (get_speed world)) (set_y world (- (get_speed world)))(get_data world))]
   [else (get_data world)]
   ))

(define (collides world) (if (inside_fruit world) (set_colides world #t) (set_colides world #f)))

(define (colision world) (if (get_colides world) (fruit_random world) (get_data world)))

(define (tick world) (tick_snake (colision (collides world))))

(define (input world key)
  (
   cond
   [(equal? key "left") (set_direction world 4)]
   [(equal? key "right") (set_direction world 6)]
   [(equal? key "up") (set_direction world 2)]
   [(equal? key "down") (set_direction world 8)]
   [(equal? key "q") (make_new_data)]
   [else (set_direction world (get_direction world))]
   ))

(big-bang (make_new_data)
          (on-tick tick)
          (on-key input)
          (on-draw draw)
          (name "Snake")
          )