#import libraries
import pygame 
import random

#initialise pygame
pygame.init()

#game window dimensions
SCREEN_WIDTH = 400
SCREEN_HEIGHT = 600

#create game window
screen = pygame.display.set_mode((SCREEN_WIDTH, SCREEN_HEIGHT))
pygame.display.set_caption('Jumpy')

#set framerate
clock = pygame.time.Clock()
FPS = 60

#game variables
SCROLL_THRESH = 200
GRAVITY = 1
MAX_PLATFORMS = 10
scroll = 0
bg_scroll = 0
game_over = False
score = 0


#define colour
WHITE = (255, 255, 255)

#define font
font_small = pygame.font.SysFont('Lucida Sans', 20)
font_big = pygame.font.SysFont('Lucida Sans', 24)

#load images
bg_image = pygame.image.load('assets/bg.png').convert_alpha()
jumpy_image = pygame.image.load('assets/jumpy.png').convert_alpha()
platform_image = pygame.image.load('assets/wood.png').convert_alpha
# ----- End of Part 1 ----- #

#function for outputting text
def draw_text(text, font, text_col, x ,y ):
    img = font.render(text, True, text_col)
    screen.blit(img, (x,y))

#function for drawing the background
def draw_bg(bg_scroll):
    screen.blit(bg_image, (0, 0 + bg_scroll))
    screen.blit(bg_image, (0, 600 + bg_scroll))

#player class
class Player():
    def __init__(self, x, y):
        self.image = pygame.transform.scale(jumpy_image, (45,45))
        self.width = 25
        self.height = 40
        self.rect = pygame.Rect(0, 0, self.width, self.height)
        self.rect.center = (x,y)
        self.vel_y = 0
        self.flip = False 

    def move(self):
        #reset variables
        dx = 0
        dy = 0

        #process keypresses
        key = pygame.key.get_pressed()
        if key[pygame.K_a]:
            dx = -10
            self.flip = True
        if key[pygame.K_d]:
            dx = 10
            self.flip = False
        
        #gravity
        self.vel_y += GRAVITY
        dy += self.vel_y

        #ensure player doesnt go off edge
        if self.rect.left + dx < 0:
            dx = -self.rect.left
        if self.rect.right + dx > SCREEN_WIDTH:
            dx = SCREEN_WIDTH - self.rect.right

        #check collision with platforms
        for platform in platform_group:
            #collision in y direction
            if platform.rect.colliderect(self.rect.x, self.rect.y + dy, self.width, self.height):
                #check if above platform
                if self.rect.bottom < platform.rect.centery:
                    if self.vel_y > 0:
                        self.rect.bottom = platform.rect.top
                        dy = 0
                        self.vel_y = -20
                        # ---- End of Part 5 --- #

        
        #check collision with ground
        if self.rect.bottom + dy > SCREEN_HEIGHT:
            dy = 0
            self.vel_y =  -20
            # ---- End of Part 4 ---- #

        #check if player has bounced to the top of the screen
        if self.rect.top <= SCROLL_THRESH:
            #if player is jumping
            if self.vel_y < 0:
                scroll = -dy

        
        
        #update rectangle position
        self.rect.x += dx
        self.rect.y += dy + scroll

        return scroll

    def draw(self):
        screen.blit(pygame.transform.flip(self.image, self.flip, False), (self.rect.x - 12, self.rect.y - 5))
        # ----- Part 3 ends here ----- #
        pygame.draw.rect(screen, WHITE, self.rect, 2)
        # ----- Part 2 ends here ----- #
#platform class
class Platform(pygame.sprite.Sprite):
    def __init__(self, x, y, width):
        pygame.sprite.Sprite.__init__(self)
        self.image = pygame.transform.scale(platform_image, (width, 10))
        self.rect = self.image.get_rect()
        self.rect.x = x
        self.rect.y = y
    
    def update(self, scroll):

        #update platforms vertical position
        self.rect.y += scroll
        
        #check if platform has gone off screen
        if self.rect.top > SCREEN_HEIGHT:
            self.kill()
            # ---- Part 7 Ends here ---- #


    
#player instance
jumpy = Player(SCREEN_WIDTH // 2, SCREEN_HEIGHT - 150)

#create sprite groups
platform_group = pygame.sprite.Group()

#create starting platform
platform = Platform(SCREEN_WIDTH // 2 -50, SCREEN_HEIGHT - 50, 100)
platform_group.add(platform)


#main loop
run = True
while run:

    clock.tick(FPS)

    if game_over == False:
        scroll = jumpy.move()

    print(scroll)

    #draw background
    bg_scroll += scroll
    if bg_scroll >= 600:
        bg_scroll = 0
    draw_bg(bg_scroll)
    # ---- Part 6 Ends Here ---- #

    #generate platforms
    if len(platform_group) < MAX_PLATFORMS:
        p_w =random.randint(40,60)
        p_x = random.randint(0, SCREEN_WIDTH - p_w )
        p_y = platform.rect.y - random.randint(80,120)
        platform = Platform(p_x, p_y, p_w)
        platform = Platform(SCREEN_WIDTH // 2 -50, SCREEN_HEIGHT - 50, 100)
        platform_group.add(platform)

    print((len(platform_group)))

    #draw temp scroll
    pygame.draw.line(screen,WHITE, (0, SCROLL_THRESH, (SCREEN_WIDTH), SCROLL_THRESH))

    #update platforms
    platform_group.update(scroll)

    #draw sprites
    platform_group.draw(screen)
    jumpy.draw()

    #check game over
    if jumpy.rect.top > SCREEN_HEIGHT:
        game_over = True
else:
     draw_text('GAME OVER!', font_big, WHITE, 130, 200)
     draw_text('SCORE: ' + str(score), font_big, WHITE, 130, 250)
     draw_text('PRESS SPACE TO PLAY AGAIN', font_big, WHITE, 40, 300)
     key = pygame.key.get_pressed() 
     if key[pygame.K_SPACE]:
         #reset variables
         game_over = False
         score = 0
         scroll = 0
         #reposition jumpy
         jumpy.rect = Player(SCREEN_WIDTH, // 2, SCREEN_HEIGHT - 150)
         #reset platforms
         platform_group.empty()



#event handler
for event in pygame.event.get():
        if event.type == pygame.QUIT:
            run = False
    #update display window
        pygame.display.update()


pygame.quit()