#include <allegro.h>




#define DOWN_RIGHT 0
#define UP_RIGHT 1
#define DOWN_LEFT 2
#define UP_LEFT 3

	void moveBall(void);
	void respondToKeyboard(void);
	void reverseVerticalDirection(void);
	void reverseHorizontalDirection(void);

	int ball_x;
	int ball_y;
	int bar1_x;
	int direction;
	BITMAP *ball;
	BITMAP *buffer;
	SAMPLE *boing;
	BITMAP *bar;

	int main(void)
	{
		allegro_init();
		install_keyboard();
		install_sound(DIGI_AUTODETECT, MIDI_AUTODETECT, NULL);
		set_color_depth(16);
		set_gfx_mode(GFX_AUTODETECT_WINDOWED, 640, 480, 0, 0);
		ball = load_bitmap("ball.bmp", NULL);
		buffer = create_bitmap(SCREEN_W, SCREEN_H);
		boing = load_sample("cartoon008.wav");
		bar = load_bitmap("paddle.bmp", NULL);
		ball_x = SCREEN_W / 2;
		ball_y = SCREEN_H / 2;
		bar1_x = SCREEN_H / 2;
		srand(time(NULL));
		direction = rand() % 4;

		while (!key[KEY_ESC])
		{
			moveBall();
			respondToKeyboard();
			clear_to_color(buffer, makecol(255, 255, 255));
			blit(ball, buffer, 0, 0, ball_x, ball_y, ball->w, ball->h);
			blit(bar, buffer, 0, 0, 0, bar1_x, bar->w, bar->h);
			blit(buffer, screen, 0, 0, 0, 0, buffer->w, buffer->h);
			clear_bitmap(buffer);
		}
		destroy_bitmap(ball);
		destroy_bitmap(bar);
		destroy_bitmap(buffer);
		destroy_sample(boing);
		return 0;
	}
	END_OF_MAIN()

		void moveBall()
	{
		switch (direction) {
		case DOWN_RIGHT:
			++ball_x;
			++ball_y;
			break;
		case UP_RIGHT:
			++ball_x;
			--ball_y;
			break;
		case DOWN_LEFT:
			--ball_x;
			++ball_y;
			break;
		case UP_LEFT:
			--ball_x;
			--ball_y;
			break;
		}

		if (ball_y <= 30 || ball_y >= 440)
			reverseVerticalDirection();
		if (ball_x <= 0 || ball_x >= 600)
			reverseHorizontalDirection();
	}
	void respondToKeyboard()
	{
		if (key[KEY_UP])
			bar1_x += -3;
		if (key[KEY_DOWN])
			bar1_x -= -3;

		if (bar1_x < 0)
			bar1_x = 0;
		else if (bar1_x > 380)
			bar1_x = 380;


	}
	void reverseVerticalDirection()
	{
		if ((direction % 2) == 0)
			++direction;
		else
			--direction;
		play_sample(boing, 255, 128, 1000, 0);
	}
	void reverseHorizontalDirection()
	{
		direction = (direction + 2) % 4;
		play_sample(boing, 255, 128, 1000, 0);
	}