import pygame
import random

# Window size
WINDOW_WIDTH    = 800
WINDOW_HEIGHT   = 400
WINDOW_SURFACE  = pygame.HWSURFACE|pygame.DOUBLEBUF|pygame.RESIZABLE

DARK_BLUE = (   3,   5,  54 )

class RotationSprite( pygame.sprite.Sprite ):
    def __init__( self, image, x, y, ):
        pygame.sprite.Sprite.__init__(self)
        self.original = image
        self.image    = image
        self.rect     = self.image.get_rect()
        self.rect.center = ( x, y )
        # for maintaining trajectory
        self.position    = pygame.math.Vector2( ( x, y ) )
        self.velocity    = pygame.math.Vector2( ( 0, 0 ) )

    def lookAt( self, co_ordinate ):
        # Rotate image to point in the new direction
        delta_vector  = co_ordinate - self.position
        radius, angle = delta_vector.as_polar()
        self.image    = pygame.transform.rotozoom( self.original, -angle, 1 )
        # Re-set the bounding rectagle
        current_pos      = self.rect.center
        self.rect        = self.image.get_rect()
        self.rect.center = current_pos



### initialisation
pygame.init()
pygame.mixer.init()
window = pygame.display.set_mode( ( WINDOW_WIDTH, WINDOW_HEIGHT ), WINDOW_SURFACE )
pygame.display.set_caption( "Rotation Example" )

### Missiles!
rotation_sprites = pygame.sprite.Group()
rotation_image1 = pygame.image.load( 'canss.png' )
rotation_image2 = pygame.image.load( 'canss.png' )
rotation_sprites.add( RotationSprite( rotation_image1, WINDOW_WIDTH//3, WINDOW_HEIGHT//2 ) )
rotation_sprites.add( RotationSprite( rotation_image2, 2*( WINDOW_WIDTH//3 ), WINDOW_HEIGHT//2 ) )


### Main Loop
clock = pygame.time.Clock()
done = False
while not done:

    # Handle user-input
    for event in pygame.event.get():
        if ( event.type == pygame.QUIT ):
            done = True
        elif ( event.type == pygame.MOUSEBUTTONUP ):
            # On mouse-click
            pass

    # Record mouse movements for positioning the paddle
    mouse_pos = pygame.mouse.get_pos()
    for m in rotation_sprites:
        m.lookAt( mouse_pos )
    rotation_sprites.update()

    # Update the window, but not more than 60 FPS
    window.fill( DARK_BLUE )
    rotation_sprites.draw( window )
    pygame.display.flip()

    # Clamp FPS
    clock.tick_busy_loop(60)

pygame.quit()