/* vi: set ts=2:
 *
 *	
 *	Eressea PB(E)M host Copyright (C) 1998-2000
 *      Christian Schlittchen (corwin@amber.kn-bremen.de)
 *      Katja Zedel (katze@felidae.kn-bremen.de)
 *      Henning Peters (faroul@beyond.kn-bremen.de)
 *      Enno Rehling (enno@eressea-pbem.de)
 *      Ingo Wilken (Ingo.Wilken@informatik.uni-oldenburg.de)
 *
 *  based on:
 *
 * Atlantis v1.0  13 September 1993 Copyright 1993 by Russell Wallace
 * Atlantis v1.7                    Copyright 1996 by Alex Schröder
 *
 * This program may not be used, modified or distributed without
 * prior permission by the authors of Eressea.
 * This program may not be sold or used commercially without prior written
 * permission from the authors.
 */

/*
 * Eressea Weather system. Compile with -DWEATHER to use this module
 */

#ifdef WEATHER

#include <config.h>
#include <eressea.h>
#include "weather.h"

/* libc includes */
#include <math.h>

weather *
create_weather(region *r, weather_t type)

{
	weather *w;

	w = calloc(1, sizeof(weather));
	w->center[0] = r->x;
	w->center[1] = r->y;
	w->type      = type;
	w->move[0]   = (rand()%3) - 1;
	w->move[1]   = (rand()%3) - 1;

	switch(type) {
	case WEATHER_STORM:
		w->radius = rand()%2+1;
		break;
	case WEATHER_HURRICANE:
		w->radius = 1;
		break;
	default:
		w->radius = 0;
	}

	addlist(&weathers, w);

	return w;
}

double
distance(int x1, int y1, int x2, int y2)

{
	return sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
}

/* Diese Funktion ermittelt für jede Region, welches Wetter in ihr
   herrscht. Die Wettertypen sind dabei nach ihrer Reihenfolge in der
	 enumeration priorisiert.

	 - Einladen
	 set_weather();
	 - Eigentliche Auswertung
	 - Veränderungen des Wetters
	 set_weather();
	 - Report generieren
	 - Abspeichern

	 Diese Routine ist sehr rechenaufwendig!
*/

void
set_weather(void)

{
	weather_t i;
	weather		*w;
	short			x, y;
	int				d;
	region		*r;

	for(r=regions;r;r=r->next) {
		r->weathertype = WEATHER_NONE;
	}

	for(i = 0; i < MAXWEATHERS; i++) {
		for(w = weathers; w; w = w->next) {
			if(w->type == i) {
				for(x=w->center[0]-w->radius; x<=w->center[0]+w->radius; x++) {
					for(y=w->center[1]-w->radius; y<=w->center[1]+w->radius; y++) {
						d = distance(w->center[0], w->center[1], x, y);
						if(floor(d+0.5) <= w->radius) {
							r = findregion(x,y);
							if(r) {
								r->weathertype = w->type;
							}
						}
					}
				}
			}
		}
	}
}

void
move_weather(void)

{
	weather		*w, *wnext;
	region    *r;

	for(w = weathers; w;) {
		wnext = w->next;
		w->center[0] = w->center[0] + w->move[0];
		w->center[1] = w->center[1] + w->move[1];
		r = findregion(w->center[0], w->center[1]);
		if(!r || rand()%100 < 5) {
			removelist(&weathers, w);
		}
		w = wnext;
	}
}

#else
#include <stdio.h>
static const char* copyright = "(c) Eressea PBEM 2000";

void
init_weather(void)
{
	fputs(copyright, stderr);
	/* TODO: Initialization */
}
#endif