/*
 * 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 3 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 <http://www.gnu.org/licenses/>.
 */

#include <element.h>

int update_MERC(UPDATE_FUNC_ARGS) {
	int r, rx, ry, trade, np;
	int maxtmp = ((10000/(parts[i].temp + 1))-1);
	if ((10000%((int)parts[i].temp+1))>rand()%((int)parts[i].temp+1))
		maxtmp ++;
	if (parts[i].tmp < maxtmp)
	{
		for (rx=-1; rx<2; rx++)
			for (ry=-1; ry<2; ry++)
				if (x+rx>=0 && y+ry>0 && x+rx<XRES && y+ry<YRES && (rx || ry))
				{
					r = pmap[y+ry][x+rx];
					if (!r || (parts[i].tmp >=maxtmp))
						continue;
					if ((r&0xFF)==PT_MERC&&33>=rand()/(RAND_MAX/100)+1)
					{
						if ((parts[i].tmp + parts[r>>8].tmp + 1) <= maxtmp)
						{
							parts[i].tmp += parts[r>>8].tmp + 1;
							kill_part(r>>8);
						}
					}
				}
	}
	else
		for (rx=-1; rx<2; rx++)
			for (ry=-1; ry<2; ry++)
				if (x+rx>=0 && y+ry>0 && x+rx<XRES && y+ry<YRES && (rx || ry))
				{
					r = pmap[y+ry][x+rx];
					if (parts[i].tmp<=maxtmp)
						continue;
					if ((!r)&&parts[i].tmp>=1)//if nothing then create deut
					{
						np = create_part(-1,x+rx,y+ry,PT_MERC);
						if (np<0) continue;
						parts[i].tmp--;
						parts[np].temp = parts[i].temp;
						parts[np].tmp = 0;
					}
				}
	for ( trade = 0; trade<4; trade ++)
	{
		rx = rand()%5-2;
		ry = rand()%5-2;
		if (x+rx>=0 && y+ry>0 && x+rx<XRES && y+ry<YRES && (rx || ry))
		{
			r = pmap[y+ry][x+rx];
			if (!r)
				continue;
			if ((r&0xFF)==PT_MERC&&(parts[i].tmp>parts[r>>8].tmp)&&parts[i].tmp>0)//diffusion
			{
				int temp = parts[i].tmp - parts[r>>8].tmp;
				if (temp ==1)
				{
					parts[r>>8].tmp ++;
					parts[i].tmp --;
				}
				else if (temp>0)
				{
					parts[r>>8].tmp += temp/2;
					parts[i].tmp -= temp/2;
				}
			}
		}
	}
	return 0;
}