/*
	This file is part of Bolixo.

	Bolixo 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 3 of the License, or
	(at your option) any later version.

	Bolixo 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 Bolixo.  If not, see <https://www.gnu.org/licenses/>.
*/
/*
	Generate a background image for bolixo.
	It uses a random generator to create a mesh.
	It generates openscad language used to render the mesh.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <tlmplib.h>
#include <string>
#include <vector>

using namespace std;

struct POINT{
	unsigned x;
	unsigned y;
	bool connected;
	POINT(){
		x=0;
		y=0;
		connected = false;
	}
	POINT (unsigned _x, unsigned _y){
		x = _x;
		y = _y;
		connected = false;
	}
};
<mod>
int main (int argc, char *argv[])
{
	glocal int ret = -1;
	glocal unsigned count = 50;
	glocal.ret = <call tlmpprogram>(argc,argv);
	<f init>
		setproginfo ("","0.0","...");
		setarg ('c',"count","Number of points",glocal.count,false);
	</f>
	<f main>
		int ret = -1;
		printf ("include <background.scad>\n");
		FILE *fin = fopen ("/dev/urandom","r");
		if (fin != NULL){
			vector<POINT> points;
			for (unsigned i=0; i<glocal.count; i++){
				unsigned char buf[2];
				if (fread (buf,2,1,fin)!=1){
					tlmp_error ("Can't read /dev/urandom\n");
					exit (-1);
				}
				points.emplace_back(buf[0],buf[1]);
			}
			for (unsigned i=0; i<glocal.count; i++){
				POINT &pt = points[i];
				// We will connect this point to 2 others
				// Each one will be selected randomly.
				// 3 points are picked and the closest is used
				for (unsigned k=0; k<2; k++){
					unsigned tb[3];
					for (unsigned j=0; j<3; j++){
						unsigned char buf[1];
						if (fread (buf,1,1,fin)!=1){
							tlmp_error ("Can't read /dev/urandom\n");
							exit (-1);
						}
						tb[j] = buf[0] % glocal.count;
					}
					// Find the closest point
					unsigned closest = 0;
					unsigned long distance=(unsigned long)-1;
					for (unsigned j=0; j<3; j++){
						POINT &p = points[tb[j]];
						int diffx = p.x - pt.x;
						int diffy = p.y - pt.y;
						unsigned long dist = diffx*diffx+diffy*diffy;
						if (dist < distance){
							closest = j;
							distance = dist;
						}
					}
					POINT &pt2 = points[closest];
					printf ("line(%u,%u,%u,%u);\n",pt.x,pt.y,pt2.x,pt2.y);
				}
			}
			fclose (fin);
			ret = 0;
		}
		return ret;
	</f>
	</call>
	return glocal.ret;
}
</mod>