#include <allegro.h>
#include <string.h>
#include <stdio.h>
#include <sys/poll.h>


void create_pipes (BITMAP *pipes[16], int size)
{
	for (int i = 0; i < 16; ++i) {
		pipes[i] = create_video_bitmap(size,size);
		clear_to_color (pipes[i], pipes[i]->vtable->mask_color);
		int max_step = size/8;
		for (int step = 0; step < max_step; ++step) {
			float h = 1 - (max_step-step)*(max_step-step)/(float)(max_step*max_step);
			int col = makecol(0,(int)(128+127*h)*size/64,(int)(128+127*h)*size/64);

			if (i&1) rectfill (pipes[i], size/2 - max_step + step, size/2 - max_step + step, size-1, size/2 + max_step - step, col);
			if (i&2) rectfill (pipes[i], 0, size/2 - max_step + step, size/2 + max_step - step, size/2 + max_step - step, col);
			if (i&4) rectfill (pipes[i], size/2 - max_step + step, size/2 - max_step + step, size/2 + max_step - step, size-1, col);
			if (i&8) rectfill (pipes[i], size/2 - max_step + step, 0, size/2 + max_step - step, size/2 + max_step - step, col);
		}
	}
}


volatile int fps = 0;
volatile int frames_this_second = 0;

void fps_timer(void)
{
	fps = frames_this_second;
	frames_this_second = 0;
}



int main(void)
{
	TRACE("1\n");
	allegro_init();
	TRACE("2\n");
	install_timer();
	TRACE("3\n");
	install_joystick(JOY_TYPE_AUTODETECT);
	TRACE("4\n");

	set_color_depth(8);
	TRACE("5\n");

	set_gfx_mode (GFX_AUTODETECT, 320, 240, 320, 1024);
	TRACE("6\n");
	
	PALETTE pal;
	memcpy (pal, default_palette, sizeof pal);
	
	for (int i = 0; i < 63; ++i) {
		pal[i+16].r = 0;
		pal[i+16].g = i;
		pal[i+16].b = i;
	}

	set_palette(pal);
	TRACE("7\n");

	BITMAP *screen_page[2];
	screen_page[0] = create_video_bitmap (SCREEN_W, SCREEN_H);
	screen_page[1] = create_video_bitmap (SCREEN_W, SCREEN_H);

	BITMAP *active_page = screen_page[0];
	clear_to_color(active_page, makecol(0,0,0));
	show_video_bitmap(active_page);
	TRACE("8\n");


	install_int (fps_timer, 1000);
	

	enum { MAX_LAYERS=8 };
	BITMAP *pipes[MAX_LAYERS][16];
	int size = 64;
	for (int i = 0; i < MAX_LAYERS; ++i) {
		create_pipes(pipes[i], size);
		size = (size * 3) / 4;
	}

	enum {
		MAP_W = 32,
		MAP_H = 32,
		JOIN_PERCENT = 30,
		MOVE_RATE = 16
	};

	char pipemap[MAX_LAYERS][MAP_W][MAP_H];
	for (int i = 0; i < MAX_LAYERS; ++i) {
		memset(pipemap[i],0,sizeof pipemap[i]);
		int num_joins = MAP_W*MAP_H*2*JOIN_PERCENT/100;
		for (int j = 0; j < num_joins; ++j) {
			bool done = false;
			do {
				int x = rand()%MAP_W;
				int y = rand()%MAP_H;
				int dir = 1 << ((rand()>>4)&2);

				if ((pipemap[i][x][y] & dir) == 0) {
					pipemap[i][x][y] |= dir;
					if (dir&1)
						x = (x+1)%MAP_W;
					else if (dir&4)
						y = (y+1)%MAP_H;
					pipemap[i][x][y] |= dir<<1;
					done = true;
				}
			} while (!done);
		}
	}

	int offset_x = 0;
	int offset_y = 0;
		
	do {
		poll_joystick();
		if (joy[0].stick[0].axis[0].d1) --offset_x;
		if (joy[0].stick[0].axis[0].d2) ++offset_x;
		if (joy[0].stick[0].axis[1].d1) --offset_y;
		if (joy[0].stick[0].axis[1].d2) ++offset_y;

		while (offset_x < 0) offset_x += MAP_W*MOVE_RATE;
		while (offset_y < 0) offset_y += MAP_H*MOVE_RATE;
		while (offset_x >= MAP_W*MOVE_RATE) offset_x -= MAP_W*MOVE_RATE;
		while (offset_y >= MAP_H*MOVE_RATE) offset_y -= MAP_H*MOVE_RATE;

		int dx = offset_x / MOVE_RATE;
		int dy = offset_y / MOVE_RATE;
		int remx = offset_x - dx*MOVE_RATE;
		int remy = offset_y - dy*MOVE_RATE;
		

		clear_to_color (active_page, makecol(0,0,0));
		
		textprintf_ex (active_page, font, 0, 0, makecol(255,255,255), -1, "%d fps   %d/%d,%d/%d", fps, dx, remx, dy, remy);
		
		set_clip_rect (active_page, 0, 10, active_page->w-1, active_page->h-1);

		for (int layer = MAX_LAYERS-1; layer >= 0; --layer) {
			int size = pipes[layer][0]->w;
			int disp_w = (SCREEN_W+size-1)/size + 1;
			int disp_h = (SCREEN_H-10+size-1)/size + 1;
			
			for (int x = 0; x < disp_w; ++x) {
				for (int y = 0; y < disp_h; ++y) {
					int pipe = pipemap[layer][(x+dx)%MAP_W][(y+dy)%MAP_H];
					draw_sprite (active_page, pipes[layer][pipe], x*size - (remx*size)/MOVE_RATE, 10 + y*size - (remy*size)/MOVE_RATE);
				}
			}
		}

		set_clip_rect (active_page, 0, 0, active_page->w-1, active_page->h-1);

		++frames_this_second;
		show_video_bitmap(active_page);
		if (active_page == screen_page[0])
			active_page = screen_page[1];
		else
			active_page = screen_page[0];
	} while (!joy[0].button[1].b);

	return 0;
}

END_OF_MAIN()