import pygame
import time
import random

pygame.init()

white = (255, 255, 255)
black = (0, 0, 0)
red = (255, 0, 0)
green = (0, 155, 0)
blue = (0, 0, 255)

display_width = 1440
display_height = 900

gameDisplay = pygame.display.set_mode((display_width, display_height))
pygame.display.set_caption('Slither')

icon = pygame.image.load("icon.png")
pygame.display.set_icon(icon)

img = pygame.image.load("snakehead.png")
appleimg = pygame.image.load("apple.png")

clock = pygame.time.Clock()

block_size = 20
FPS = 17

direction = "right"
smallfont = pygame.font.SysFont ("arial", 25)
medfont = pygame.font.SysFont ("arial", 50)
largefont = pygame.font.SysFont ("arial", 80)


def game_intro():

    intro = True

    while intro:

        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                pygame.quit()
                quit()

            if event.type == pygame.KEYDOWN:
                if event.key == pygame.K_c:
                    intro = False
                if event.key == pygame.K_q:
                    pygame.quit()
                    quit()


        gameDisplay.fill(white)
        message_to_screen("Welcome to the Snake Game!",
                          green,
                          -100,
                          size="large")
        message_to_screen("The goal of the game is to eat the red apples",
                          black,
                          -30)
        message_to_screen("You get longer each time you eat an apple",
                          black,
                          10)
        message_to_screen("If you run into yourself, or the edge of the map, you die.",
                          black,
                          50)
        message_to_screen("Press C to play or Q to quit",
                          black,
                          180)

        pygame.display.update()
        clock.tick(17)



font = pygame.font.SysFont(None, 25)

def snake(block_size, snakeList):

    if direction == "right":
        head = pygame.transform.rotate(img, 270)
    if direction == "left":
        head = pygame.transform.rotate(img, 90)
    if direction == "up":
        head = img
    if direction == "down":
        head = pygame.transform.rotate(img, 180)

    gameDisplay.blit(head, (snakeList[-1][0], snakeList[-1][1]))

    for XnY in snakeList[:-1]:
        pygame.draw.rect(gameDisplay, green, [XnY[0], XnY[1], block_size, block_size])

def text_objects(text, color, size):
    if size == "small":
        textSurface = smallfont.render(text,True, color)
    elif size == "medium":
        textSurface = medfont.render(text,True, color)
    elif size == "large":
        textSurface = largefont.render(text,True, color)
    textSurface = font.render(text, True, color)
    return textSurface, textSurface.get_rect()

def message_to_screen(msg,color, y_displace=0, size = "small"):
    textSurf, textRect = text_objects(msg, color, size)
    textRect.center = (display_width / 2), (display_height / 2) +y_displace
    gameDisplay.blit(textSurf, textRect)

 ## def score_to_screen(msg,color):
   ## textSurf, textRect = text_objects(msg, color)
   ## textRect.center = (display_width / 8), (display_height / 8)
   ## gameDisplay.blit(textSurf, textRect)




def gameLoop():
    global direction

    direction = "right"
    snakeLength = 1
    gameExit = False
    gameOver = False

    lead_x = display_width / 2
    lead_y = display_height / 2

    lead_x_change = 0
    lead_y_change = 0

    snakeList = []
    snakeLength = 1




    while not gameExit:

        while gameOver == True:
            gameDisplay.fill(white)
            message_to_screen("Game over",
                              red,
                              -50,
                              size = "large")
            message_to_screen("Press C to play again or Q to quit",
                              black,
                              50,
                              size = "medium")
            pygame.display.update()

            for event in pygame.event.get():
                if event.type == pygame.QUIT:
                    gameExit = True
                    gameOver = False
                if event.type == pygame.KEYDOWN:
                    if event.key == pygame.K_q:
                        gameExit = True
                        gameOver = False
                    if event.key  == pygame.K_c:
                        gameLoop()


        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                gameExit = True
            if event.type == pygame.KEYDOWN:
                if event.key == pygame.K_LEFT:
                    direction = "left"
                    lead_x_change = -block_size
                    lead_y_change = 0
                elif event.key == pygame.K_RIGHT:
                    direction = "right"
                    lead_x_change = block_size
                    lead_y_change = 0

                elif event.key == pygame.K_UP:
                    direction = "up"
                    lead_y_change = -block_size
                    lead_x_change = 0
                elif event.key == pygame.K_DOWN:
                    direction = "down"
                    lead_y_change = block_size
                    lead_x_change = 0

        if lead_x >= display_width or lead_x < 0 or lead_y >= display_height or lead_y < 0:
            gameOver = True

        lead_x += lead_x_change
        lead_y += lead_y_change


        gameDisplay.fill(black)

        AppleThickness = 30
        #pygame.draw.rect(gameDisplay, red, [randAppleX, randAppleY, AppleThickness, AppleThickness])



        snakeHead = []
        snakeHead.append(lead_x)
        snakeHead.append(lead_y)
        snakeList.append(snakeHead)

        if len(snakeList) > snakeLength:
            del snakeList[0]

        for eachSegment in snakeList[:-1]:
            if eachSegment == snakeHead:
                gameOver = True

        ## score_to_screen("Score: " + str(snakeLength - 1), blue)
        ## snake(block_size, snakeList)

        snake(block_size, snakeList)
        pygame.display.update()
        snakeLength += 1
        clock.tick(FPS)


    pygame.quit()
    quit()
game_intro()
gameLoop()