/*
  Copyright (C) 2018 David Robillard <d@drobilla.net>

  This program is free software: you can redistribute it and/or modify it under
  the terms of the GNU General Public License as published by the Free Software
  Foundation, either version 2 of the License, or (at your option) any later
  version.

  This program is distributed in the hope that it will be useful, but WITHOUT
  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  details.

  You should have received a copy of the GNU General Public License along with
  this program.  If not, see <https://www.gnu.org/licenses/>.
*/

#include "chilbert/chilbert.hpp"

#include <array>
#include <cmath>
#include <cstdint>
#include <cstdio>
#include <cstdlib>

int
main(int argc, char** argv)
{
	if (argc != 2) {
		fprintf(stderr, "Usage: %s NUM_POINTS\n", argv[0]);
		return 1;
	}

	const unsigned long num_points = std::strtoul(argv[1], nullptr, 10);
	if (num_points == 0 || num_points == ULONG_MAX) {
		fprintf(stderr, "Usage: %s NUM_POINTS\n", argv[0]);
		return 1;
	}

	const uint32_t w =
	  uint32_t(sqrt(1 << uint32_t(ceil(log2(double(num_points)))))) - 1;

	// Header
	printf("<svg xmlns='http://www.w3.org/2000/svg'"
	       " version='1.2' baseProfile='tiny' viewBox='0 0 %u %u'>\n",
	       w,
	       w);
	printf("<desc>Hilbert Curve</desc>\n");
	printf("<polyline vector-effect='non-scaling-stroke' fill='none' "
	       "stroke='black' stroke-width='1' points='");

	// One polyline through all vertices
	for (uint64_t i = 0; i <= num_points; ++i) {
		std::array<uint32_t, 2> point;
		chilbert::index_to_coords(point.data(), 32, 2, i);
		printf("%u,%u ", point[0], point[1]);
	}

	// Close off document
	printf("' />\n</svg>\n");

	return 0;
}