#define ROAD_NUM		512
#define ROAD_WIDTH_BY_2 200
#define CAR_WIDTH_BY_2	100

I64  road_x[ROAD_NUM], road_trend;
F64  speed, distance;
I64  road_ptr = 0, car_x;
F64  t_last;
Bool crash;

U0 DrawIt(CTask *task, CDC *dc)
{
	I64 w = task->pix_width, h = task->pix_height;
	I64 i, x, y, xx;

	xx = w >> 1 - car_x + road_x[road_ptr & (ROAD_NUM - 1)];

	dc->color = LTGRAY;
	for (i = 0; i < ROAD_NUM; i++)
	{
		x = w >> 1 - car_x + road_x[(i + road_ptr) & (ROAD_NUM - 1)];
		y = h - 0.5 * i;
		if (y < (h + FONT_HEIGHT) >> 1)
			break;
		GrPlot(dc, x + ROAD_WIDTH_BY_2 - 0.4 * i, y);
		GrPlot(dc, x - ROAD_WIDTH_BY_2 + 0.4 * i, y);
	}
	dc->color = WHITE;

	x = w >> 1 - CAR_WIDTH_BY_2;
	if (x < xx - ROAD_WIDTH_BY_2)
		crash = TRUE;
	GrLine(dc, x - 10, h, x - 40, h - 100);
	GrLine(dc, x + 10, h, x + 40, h - 100);

	x = w >> 1 + CAR_WIDTH_BY_2;
	if (x > xx + ROAD_WIDTH_BY_2)
		crash = TRUE;
	GrLine(dc, x - 10, h, x - 40, h - 100);
	GrLine(dc, x + 10, h, x + 40, h - 100);

	dc->color = YELLOW;
	if (crash)
		GrPrint(dc, w >> 1 - FONT_WIDTH * 4, (h - FONT_HEIGHT) >> 1, "Game Over");
}

U0 UpdateRoad()
{
	F64 t0 = tS;

	distance += speed * (t0 - t_last);
	t_last = t0;
	while (distance > 1.0)
	{
		road_trend = ClampI64(road_trend + SignI64(RandU16 % 3 - 1), -5, 5);
		road_x[road_ptr & (ROAD_NUM - 1)] = road_x[(road_ptr - 1) & (ROAD_NUM - 1)] += road_trend / 3;
		road_ptr++;
		distance -= 1.0;
	}
}

U0 Init()
{
	I64 i, x = 0;

	DocClear;
	"$$BG,DKGRAY$$%h*c", (TEXT_ROWS - 1) / 2, '\n';
	speed = 0;
	distance = 0;
	road_trend = 0;
	road_ptr = 0;
	car_x = 0;
	for (i = 0; i < ROAD_NUM; i++)
	{
		road_x[i] = x;
		road_trend = ClampI64(road_trend + SignI64(RandU16 % 3 - 1), -5, 5);
		x += road_trend / 3;
	}
	t_last = tS;
	crash = FALSE;
}

U0 Halogen()
{
	I64 arg1, arg2, ch=0, sc=0;
	SettingsPush; //See $LK,"SettingsPush",A="MN:SettingsPush"$
	Fs->text_attr = BLACK << 4 + WHITE;
	MenuPush(	"File {"
				"  Abort(,CH_SHIFT_ESC);"
				"  Exit(,CH_ESC);"
				"}"
				"Play {"
				"  Restart(,'\n');"
				"  Accelerate(,,SC_CURSOR_UP);"
				"  Deccellerate(,,SC_CURSOR_DOWN);"
				"  Left(,,SC_CURSOR_LEFT);"
				"  Right(,,SC_CURSOR_RIGHT);"
				"}"
				);
	AutoComplete;
	WinBorder;
	WinMax;
	DocCursor;
	Init;
	Fs->draw_it = &DrawIt;
	try
	{
		while (TRUE)
		{
			switch (MessageScan(&arg1, &arg2, 1 << MESSAGE_KEY_DOWN | 1 << MESSAGE_KEY_UP))
			{
				case MESSAGE_KEY_DOWN:
					ch = arg1;
					sc = arg2;
					switch (ch)
					{
						case '\n':
							Init;
							break;

						case CH_ESC:
						case CH_SHIFT_ESC:
							goto ha_done;
					}
					break;
				case MESSAGE_KEY_UP:
					ch = arg1;
					sc = arg2;
					if (!ch)
						switch (sc.u8[0])
						{
							case SC_CURSOR_RIGHT:
							case SC_CURSOR_LEFT:
							case SC_CURSOR_UP:
							case SC_CURSOR_DOWN:
								sc = 0;
								break;
						}
					break;
			}
			switch (sc.u8[0])
			{
				case SC_CURSOR_RIGHT:
					car_x++;
					break;

				case SC_CURSOR_LEFT:
					car_x--;
					break;

				case SC_CURSOR_UP:
					if (++speed > 200)
						speed = 200;
					break;

				case SC_CURSOR_DOWN:
					if (--speed < 0)
						speed = 0;
					break;
			}
			if (crash)
				Sound;
			else
			{
				if (speed)
					Sound(Freq2Ona(speed + 10));
				else
					Sound;
				UpdateRoad;
			}
			Sleep(10);
		}
ha_done:
		MessageGet(,, 1 << MESSAGE_KEY_UP);
	}
	catch
		PutExcept;
	MenuPop;
	DocClear;
	SettingsPop;
}

Halogen;
