/*
    This file is part of "life", a Filter plugin for Adobe Photoshop
    Copyright (C) 2003-6 Toby Thain, toby@telegraphics.com.au

    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, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

/* Photoshop filter implementing Conway's Life cellular automaton. */

#include "world.h"

#include "PIFilter.h"

#ifdef __SC__
	#include <memory.h>

	#define malloc NewPtr
	#define free DisposePtr

	// we need to avoid global data in the 68K build.
	// so, all global references are indirected via the "data" parameter
	// that Photoshop maintains for the plugin, and passes to it.
	#define FAKEGLOBALS
	#define G(F) ((struct globals*)*data)->F
#else
	#define G
#endif

#include "entry.h"

#include "ui.h"

#ifdef FAKEGLOBALS
struct globals{
#endif
	int toprow,chunkrows;
#ifdef FAKEGLOBALS
};
#endif

DLLEXPORT MACPASCAL 
void ENTRYPOINT(short selector,FilterRecordPtr epb,long *data,short *result);

void DoPrepare (FilterRecordPtr epb,long *data);
void DoStart (FilterRecordPtr epb,long *data);
OSErr process(FilterRecordPtr pb);
OSErr DoContinue (FilterRecordPtr epb,long *data);
void DoFinish (FilterRecordPtr epb,long *data);
void RequestNext (FilterRecordPtr epb,long*data);
OSErr process(FilterRecordPtr pb);

DLLEXPORT MACPASCAL 
void ENTRYPOINT(short selector,FilterRecordPtr pb,long *data,short *result){
	OSErr e = noErr;
	
#ifdef FAKEGLOBALS
	// allocate block for the globals struct
	// this is never freed, but re-used for future plugin invocations
	if( !*data && !( *data = (long)malloc(sizeof(struct globals)) ) )
		e = memFullErr;
	else
#endif
		switch (selector){
		case filterSelectorAbout: DoAbout((AboutRecordPtr)pb); break;
		case filterSelectorParameters: break;
		case filterSelectorPrepare: DoPrepare(pb,data); break;
		case filterSelectorStart: DoStart(pb,data); break;
		case filterSelectorContinue: e = DoContinue(pb,data); break;
		case filterSelectorFinish: DoFinish(pb,data); break;
		default:
			e = filterBadParameters;
		}
		
	*result = e;
}

void DoPrepare(FilterRecordPtr pb,long *data){
	G(chunkrows) = (pb->maxSpace/4) / ((pb->planes*pb->depth*(long)pb->imageSize.h + 7)/8);
	if(G(chunkrows) > (pb->filterRect.bottom - pb->filterRect.top))
		G(chunkrows) = pb->filterRect.bottom - pb->filterRect.top;
}

void RequestNext(FilterRecordPtr pb,long *data){
	/* Request next block of the image */

	pb->inLoPlane = pb->outLoPlane = 0;
	pb->inHiPlane = pb->outHiPlane = pb->planes-1;

	pb->inRect.left = pb->outRect.left = pb->filterRect.left;
	pb->inRect.right = pb->outRect.right = pb->filterRect.right;
	pb->inRect.top = pb->outRect.top = G(toprow);
	pb->inRect.bottom = G(toprow) + G(chunkrows);
	if(pb->inRect.bottom > pb->filterRect.bottom)
		pb->inRect.bottom = pb->filterRect.bottom;
	pb->outRect.bottom = pb->inRect.bottom;
		
//	SPRINTF(s,"RequestNext inRect = %d,%d,%d,%d",pb->inRect.left,pb->inRect.top,pb->inRect.right,pb->inRect.bottom); dbg(s);
}

void DoStart (FilterRecordPtr pb,long *data){
	G(toprow) = pb->filterRect.top;
	RequestNext(pb,data);
}

OSErr DoContinue (FilterRecordPtr pb,long *data){
	OSErr e = process(pb);
		
	G(toprow) += G(chunkrows);
	if(G(toprow) < pb->filterRect.bottom)
		RequestNext(pb,data);
	else{
		pb->inRect.left = pb->inRect.right = pb->inRect.top = pb->inRect.bottom = 0 ;
		pb->outRect = pb->maskRect = pb->inRect;
	}

	return e;
}

void DoFinish(FilterRecordPtr pb,long *data){
}