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"""
 Move a sprite in a circle.

 Sample Python/Pygame Programs
 Simpson College Computer Science
 http://programarcadegames.com/
 http://simpson.edu/computer-science/

"""

import pygame
import random
import math

# Colors
BLACK = (0, 0, 0)
WHITE = (255, 255, 255)
GREEN = (0, 255, 0)
RED = (255, 0, 0)
BLUE = (0, 0, 255)


class Block(pygame.sprite.Sprite):
    """ This class represents the ball that moves in a circle. """

    def __init__(self, color, width, height):
        """ Constructor that create's the ball's image. """
        super().__init__()
        self.image = pygame.Surface([width, height])
        self.image.fill(color)
        self.rect = self.image.get_rect()

        # The "center" the sprite will orbit
        self.center_x = 0
        self.center_y = 0

        # Current angle in radians
        self.angle = 0

        # How far away from the center to orbit, in pixels
        self.radius = 0

        # How fast to orbit, in radians per frame
        self.speed = 0.05

    def update(self):
        """ Update the ball's position. """
        # Calculate a new x, y
        self.rect.x = self.radius * math.sin(self.angle) + self.center_x
        self.rect.y = self.radius * math.cos(self.angle) + self.center_y

        # Increase the angle in prep for the next round.
        self.angle += self.speed


class Player(pygame.sprite.Sprite):
    """ Class to represent the player. """
    def __init__(self, color, width, height):
        """ Create the player image. """
        super().__init__()
        self.image = pygame.Surface([width, height])
        self.image.fill(color)
        self.rect = self.image.get_rect()

    def update(self):
        """Set the user to be where the mouse is. """
        pos = pygame.mouse.get_pos()
        self.rect.x = pos[0]
        self.rect.y = pos[1]

# Initialize Pygame
pygame.init()

# Set the height and width of the screen
SCREEN_WIDTH = 700
SCREEN_HEIGHT = 400
screen = pygame.display.set_mode([SCREEN_WIDTH, SCREEN_HEIGHT])

# This is a list of 'sprites.' Each block in the program is
# added to this list. The list is managed by a class called 'Group.'
block_list = pygame.sprite.Group()

# This is a list of every sprite. All blocks and the player block as well.
all_sprites_list = pygame.sprite.Group()

for i in range(50):
    # This represents a block
    block = Block(BLACK, 20, 15)

    # Set a random center location for the block to orbit
    block.center_x = random.randrange(SCREEN_WIDTH)
    block.center_y = random.randrange(SCREEN_HEIGHT)
    # Random radius from 10 to 200
    block.radius = random.randrange(10, 200)
    # Random start angle from 0 to 2pi
    block.angle = random.random() * 2 * math.pi
    # radians per frame
    block.speed = 0.008
    # Add the block to the list of objects
    block_list.add(block)
    all_sprites_list.add(block)

# Create a RED player block
player = Player(RED, 20, 15)
all_sprites_list.add(player)

# Loop until the user clicks the close button.
done = False

# Used to manage how fast the screen updates
clock = pygame.time.Clock()

score = 0

# -------- Main Program Loop -----------
while not done:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            done = True

    all_sprites_list.update()

    # Clear the screen
    screen.fill(WHITE)

    # See if the player block has collided with anything.
    blocks_hit_list = pygame.sprite.spritecollide(player, block_list, True)

    # Check the list of collisions.
    for block in blocks_hit_list:
        score += 1
        print( score )

    # Draw all the spites
    all_sprites_list.draw(screen)

    # Go ahead and update the screen with what we've drawn.
    pygame.display.flip()

    # Limit to 60 frames per second
    clock.tick(60)

pygame.quit()