import pygame


def initialize_constants():
    """
    This function sets some global constants (i.e., the values of these global
    variables never change).
    """
    global name
    name = raw_input("Please type in your name: ")
    
    pygame.init()

    # background pic
    global sky
    sky = pygame.image.load("sky_scaled.jpg")

    # set up the display window
    global width, height, screen
    width = sky.get_width()  ##640
    height = sky.get_height()  ##480
    screen = pygame.display.set_mode((width,height))

    sky = sky.convert() # can only convert after the video mode is set

    # load the ballon picture
    global balloon
    balloon = pygame.image.load("red_balloon.gif")
    balloon = balloon.convert()
    global balloon2
    balloon2 = pygame.image.load("green_balloon.gif")
    balloon2 = balloon2.convert()

    # load sound
    global pop_sound
    pop_sound = pygame.mixer.Sound("pop.wav")
    pygame.mixer.music.load("mario_bros_trimmed.ogg")

    # load font
    global myFont
    myFont = pygame.font.Font(None,30)


def move_and_bounce_object(dt, x, y, speed_x, speed_y, obj_width, obj_height):
    """
    This function calculates an object's new position based on its
    old position, the time that has passed since the last update,
    and its speed. It also makes sure that the object bounces
    off the edge of the screen.
    """

    x = x + dt * speed_x
    if (x < 0):
        x = 0
        speed_x = - speed_x
    elif (x > width - obj_width):
        x = width - obj_width
        speed_x = - speed_x
        
    y = y + dt * speed_y
    if (y < 0):
        y = 0
        speed_y = - speed_y
    elif (y > height - obj_height):
        y = height - obj_height
        speed_y = - speed_y

    # Here you see that in Python we can return more than one value.
    # This is a specialy of Python.
    return x, y, speed_x, speed_y


def clicked_image(mouse_x, mouse_y, x, y, w, h):

    if mouse_x >= x and mouse_x <= x+w and mouse_y >= y and mouse_y <= y+h:
        return True
    else:
        return False



def run_game():

    # initialize the balloons' positions and speeds
    b_x = 100
    b_y = 100
    b_speed_x = 0.2
    b_speed_y = 0.2
    b_w = balloon.get_width()
    b_h = balloon.get_height()

    b2_x = 300
    b2_y = 300
    b2_speed_x = 0.1
    b2_speed_y = 0.2

    # initialize the score
    score = 0

    clock = pygame.time.Clock()

    dead = False
    
    keepGoing = True

    pygame.mixer.music.play(-1)

    while (keepGoing):

        dt = clock.tick()

        # handle events
        
        for event in pygame.event.get():
            
            if event.type == pygame.QUIT:
                keepGoing = False


            # If the player clicks into the red balloon, he gets a
            # point. The game also plays a popping sound and the
            # balloon starts moving a bit faster.
            # If the player clicks outside the red balloon, he dies.
            elif not dead and event.type == pygame.MOUSEBUTTONDOWN:

                mouse_x, mouse_y = pygame.mouse.get_pos()

                if clicked_image(mouse_x, mouse_y, b_x, b_y, b_w, b_h):
                    pop_sound.play()
                    score = score + 1
                    b_speed_x = 1.1 * b_speed_x
                    b_speed_y = 1.1 * b_speed_y
                else:
                    dead = True

                    

        # Update the positions and speeds of the balloons.
        if not dead:
            b_x, b_y, b_speed_x, b_speed_y = move_and_bounce_object(dt, b_x, b_y, b_speed_x, b_speed_y, balloon.get_width(),balloon.get_height())

            b2_x, b2_y, b2_speed_x, b2_speed_y = move_and_bounce_object(dt, b2_x, b2_y, b2_speed_x, b2_speed_y, balloon2.get_width(),balloon2.get_height())


        # draw everything
        
        #screen.fill(pygame.color.Color("darkblue"))
        screen.blit(sky, (0,0))

        # score
        x = 10
        y = 10
        label = myFont.render("Your score: "+str(score), True, pygame.color.Color("magenta"))
        screen.blit(label, (x,y))


        # balloon images
        screen.blit(balloon,(b_x,b_y))
        screen.blit(balloon2,(b2_x,b2_y))

        # game over message
        if dead:
             label = myFont.render("Sorry, "+name+"! Game over!", True, pygame.color.Color("magenta"))
             screen.blit(label, ((width-label.get_width())/2,height/2-50))
             label = myFont.render("You didn't click on the red balloon.", True, pygame.color.Color("magenta"))
             screen.blit(label, ((width-label.get_width())/2,height/2-25))



        pygame.display.update()




def done():

    global myFont
    myFont = None
    
    pygame.quit()
    


def main():

    initialize_constants()

    run_game()

    done()



main()