import pygame
from pygame.locals import *

pygame.init()

SCREEN_WIDTH = 500
SCREEN_HEIGHT = 400

# set up window
window = pygame.display.set_mode((SCREEN_WIDTH, SCREEN_HEIGHT))
pygame.display.set_caption('Gravity Test')

# set up colors
BLACK = (0,0,0)
WHITE = (255,255,255)
GRAY = (47, 79, 79)  # Dark Slate Gray
SKY_BLUE = (0, 191, 255)  # Deep Sky Blue
GOLD = (218, 165, 32)  # Gold
DARK_RED = (178, 34, 34)  # Firebrick
SEA_GREEN = (60, 179, 113)  # Medium Sea Green

PLAYER_SIZE = 20
PLAYER_SPEED = 10

# jumping vars
GRAVITY = 4
jumpForce = [0, GRAVITY]

def handleKeys(player):
	keys = pygame.key.get_pressed()
	if keys[pygame.K_LEFT]:
		# left arrow key, move player left
		player.x = max(player.x - PLAYER_SPEED, 0)

	if keys[pygame.K_RIGHT]:
		# right arrow key, move player right
		player.x = min(player.x + PLAYER_SPEED, SCREEN_WIDTH - PLAYER_SIZE) 

	if keys[pygame.K_UP]:
		# only jump if player is on the ground
		if player.y == SCREEN_HEIGHT - PLAYER_SIZE:
			print('changing jump force')
			jumpForce[0] = 20

player = Rect(20, SCREEN_HEIGHT - PLAYER_SIZE, PLAYER_SIZE, PLAYER_SIZE)

running = True
while running:
	for event in pygame.event.get():
		if event.type == pygame.QUIT:
			running = False

	window.fill(GRAY)
	handleKeys(player)
	print('jumpForce = ' + str(jumpForce[0]))

	if player.y < SCREEN_HEIGHT - PLAYER_SIZE or jumpForce[0] > 0:
		player.y -= jumpForce[0]
		jumpForce[0] -= GRAVITY

	pygame.draw.rect(window, SEA_GREEN, player)
	pygame.display.update()

	pygame.time.Clock().tick(30)

pygame.quit()