import pygame, sys, random
from pygame.math import Vector2
from pygame.locals import *

# Initialize Pygame
pygame.mixer.pre_init(44100, -16, 2, 512)
pygame.init()

#Game variables
cell_size = 40
cell_number = 20


# Set up display
screen_width = cell_size * cell_number
screen_height = cell_number * cell_size
screen = pygame.display.set_mode((screen_width, screen_height))
pygame.display.set_caption('Pygame Template')
apple = pygame.image.load("SnakeImages/apple.png").convert_alpha()
game_font = pygame.font.Font("SnakeImages/PoetsenOne-Regular.ttf", 12)

# Clock for controlling frame rate
clock = pygame.time.Clock()
fps = 60


#Classes
class SNAKE:
    def __init__(self):
        self.body = [Vector2(5, 10), Vector2(4, 10), Vector2(3, 10)]
        self.direction = Vector2(0, 0)
        self.new_block = False

        self.head_up = pygame.image.load('SnakeImages/head_up.png').convert_alpha()
        self.head_down = pygame.image.load('SnakeImages/head_down.png').convert_alpha()
        self.head_right = pygame.image.load('SnakeImages/head_right.png').convert_alpha()
        self.head_left = pygame.image.load('SnakeImages/head_left.png').convert_alpha()

        self.tail_up = pygame.image.load('SnakeImages/tail_up.png').convert_alpha()
        self.tail_down = pygame.image.load('SnakeImages/tail_down.png').convert_alpha()
        self.tail_right = pygame.image.load('SnakeImages/tail_right.png').convert_alpha()
        self.tail_left = pygame.image.load('SnakeImages/tail_left.png').convert_alpha()

        self.body_vertical = pygame.image.load('SnakeImages/body_vertical.png').convert_alpha()
        self.body_horizontal = pygame.image.load('SnakeImages/body_horizontal.png').convert_alpha()

        self.body_tr = pygame.image.load('SnakeImages/body_tr.png').convert_alpha()
        self.body_tl = pygame.image.load('SnakeImages/body_tl.png').convert_alpha()
        self.body_br = pygame.image.load('SnakeImages/body_br.png').convert_alpha()
        self.body_bl = pygame.image.load('SnakeImages/body_bl.png').convert_alpha()
        self.crunch_sound = pygame.mixer.Sound('SnakeImages/crunch.wav')

    def draw_snake(self):
        self.update_head_graphics()
        self.update_tail_graphics()

        for index, block in enumerate(self.body):
            x_pos = int(block.x * cell_size)
            y_pos = int(block.y * cell_size)
            block_rect = pygame.Rect(x_pos, y_pos, cell_size, cell_size)

            if index == 0:
                screen.blit(self.head, block_rect)
            elif index == len(self.body) - 1:
                screen.blit(self.tail, block_rect)
            else:
                previous_block = self.body[index + 1] - block
                next_block = self.body[index - 1] - block
                if previous_block.x == next_block.x:
                    screen.blit(self.body_vertical, block_rect)
                elif previous_block.y == next_block.y:
                    screen.blit(self.body_horizontal, block_rect)
                else:
                    if previous_block.x == -1 and next_block.y == -1 or previous_block.y == -1 and next_block.x == -1:
                        screen.blit(self.body_tl, block_rect)
                    elif previous_block.x == -1 and next_block.y == 1 or previous_block.y == 1 and next_block.x == -1:
                        screen.blit(self.body_bl, block_rect)
                    elif previous_block.x == 1 and next_block.y == -1 or previous_block.y == -1 and next_block.x == 1:
                        screen.blit(self.body_tr, block_rect)
                    elif previous_block.x == 1 and next_block.y == 1 or previous_block.y == 1 and next_block.x == 1:
                        screen.blit(self.body_br, block_rect)

    def update_head_graphics(self):
        head_relation = self.body[1] - self.body[0]
        if head_relation == Vector2(1, 0):
            self.head = self.head_left
        elif head_relation == Vector2(-1, 0):
            self.head = self.head_right
        elif head_relation == Vector2(0, 1):
            self.head = self.head_up
        elif head_relation == Vector2(0, -1):
            self.head = self.head_down

    def update_tail_graphics(self):
        tail_relation = self.body[-2] - self.body[-1]
        if tail_relation == Vector2(1, 0):
            self.tail = self.tail_left
        elif tail_relation == Vector2(-1, 0):
            self.tail = self.tail_right
        elif tail_relation == Vector2(0, 1):
            self.tail = self.tail_up
        elif tail_relation == Vector2(0, -1):
            self.tail = self.tail_down

    def move_snake(self):
        if self.new_block == True:
            body_copy = self.body[:]
            body_copy.insert(0, body_copy[0] + self.direction)
            self.body = body_copy[:]
            self.new_block = False
        else:
            body_copy = self.body[:-1]
            body_copy.insert(0, body_copy[0] + self.direction)
            self.body = body_copy[:]


    def add_block(self):
        self.new_block = True

    def play_crunch_sound(self):
        self.crunch_sound.play()

    def restart(self):
        self.body = [Vector2(5, 10), Vector2(4, 10), Vector2(3, 10)]
        self.direction = Vector2(0, 0)

class FRUIT:
    def __init__(self):
        self.randomize()

        #create an x and y position
        #draw a square
    def draw_fruit(self):
        fruit_rect = pygame.Rect(int(self.pos.x * cell_size) ,int(self.pos.y * cell_size) ,cell_size,cell_size)
        screen.blit(apple, fruit_rect)
        #pygame.draw.rect(screen, (126, 166, 114), fruit_rect)

    def randomize(self): 
        self.x = random.randint(0, cell_number - 1)
        self.y = random.randint(0, cell_number - 1)
        self.pos = Vector2(self.x, self.y)

class MAIN:
    def __init__(self):
        self.snake = SNAKE()
        self.fruit = FRUIT()

    def update(self):
        self.snake.move_snake()
        self.check_collision()
        self.check_fail()
    
    def draw_elements(self):
        self.draw_grass()
        self.fruit.draw_fruit()
        self.snake.draw_snake()
        self.draw_score()


    def check_collision(self):
        if self.fruit.pos == self.snake.body[0]:
            #reposition the fruit
            self.fruit.randomize()
            #Add another block the the snake
            self.snake.add_block()
            self.snake.play_crunch_sound()

        for block in self.snake.body[1:]:
            if block == self.fruit.pos:
                self.fruit.randomize()

    def check_fail(self):
        # CHeck if snake is outside of screen
        if not 0 <= self.snake.body[0].x < cell_number or not 0 <= self.snake.body[0].y < cell_number:
            self.game_over()

        #Check if snake hits itself
        for block in self.snake.body[1:]:
            if block == self.snake.body[0]:
                self.game_over()

    def draw_grass(self):
        grass_colour = (167, 209, 61)

        for row in range(cell_number):
            if row % 2 == 0:
                for col in range(cell_number):
                    if col % 2 == 0:
                        grass_rect = pygame.Rect(col * cell_size, row * cell_size, cell_size, cell_size)
                        pygame.draw.rect(screen, grass_colour,grass_rect)
            else:
                for col in range(cell_number):
                    if col % 2 == 1:
                        grass_rect = pygame.Rect(col * cell_size, row * cell_size, cell_size, cell_size)
                        pygame.draw.rect(screen, grass_colour,grass_rect)
        

                

    def game_over(self):
        self.snake.restart()


    def draw_score(self):
        score_text = str(len(self.snake.body) - 3)
        score_surface = game_font.render(score_text, True, (56, 74, 12))
        score_x = int (cell_size * cell_number - 60)
        score_y = int(cell_number * cell_size - 40)
        score_rect = score_surface.get_rect(center = (score_x, score_y))
        apple_rect = apple.get_rect(midright = (score_rect.left, score_rect.centery))
        bg_rect = pygame.Rect(apple_rect.left, apple_rect.top, apple_rect.width + score_rect.width + 6, apple_rect.height)
        
        pygame.draw.rect(screen, (167, 209, 61), bg_rect)
        screen.blit(score_surface, score_rect)
        screen.blit(apple, apple_rect)
        pygame.draw.rect(screen, (56, 74, 12), bg_rect, 2)


SCREEN_UPDATE = pygame.USEREVENT
pygame.time.set_timer(SCREEN_UPDATE, 150)

main_game = MAIN()

# Main game loop
run = True
while run:
    clock.tick(fps)

    # Event handling
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            run = False
        if event.type == SCREEN_UPDATE:
            main_game.update()
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_UP:
                if main_game.snake.direction.y != 1:
                    main_game.snake.direction = Vector2(0, -1)
            if event.key == pygame.K_DOWN:
                if main_game.snake.direction.y != -1:
                    main_game.snake.direction = Vector2(0, 1)
            if event.key == pygame.K_LEFT:
                if main_game.snake.direction.x != 1:
                    main_game.snake.direction = Vector2(-1, 0)
            if event.key == pygame.K_RIGHT:
                if main_game.snake.direction.x != -1:
                    main_game.snake.direction = Vector2(1, 0)

    # Update game logic here

    # Draw everything
    screen.fill((175, 215, 70))  # Clear screen with black (or any other color)

    main_game.draw_elements()


    # Update the display
    pygame.display.update()

# Quit Pygame
pygame.quit()