/*
    This file is part of PSPFormat, a File Format plugin for Adobe Photoshop
    Copyright (C) 2003-7 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
*/

#include "pspformat.h"
#include "zlib.h"

enum{
	/* the following are maximum sizes, for estimation purposes,
	 * not necessarily correct for all PSP file format versions */
	SIZEOF_FILE_HEADER = PSP_SIG_LENGTH + 4,
	SIZEOF_BLOCK_HEADER = 14,
	SIZEOF_LAYER_INFO_CHUNK = PSP_LAYER_NAME_MAX+83+PSP_BLEND_RANGE_BYTES,
};

OSErr estimate_start(FormatRecordPtr pb, intptr_t *data){
	OSErr e = noErr;
		
	/* to communicate these values to the later Write phase,
	   we *have* to use Photoshop's data parameter;
	   globals are reinitialised between phases. */

	G->psprb = pb->imageMode == plugInModeBitmap ? PAD4(pb->imageSize.h) : pb->imageSize.h;
	G->channelsize = (long)G->psprb * pb->imageSize.v;

	// tell Photoshop we're finished with image data
	pb->data = NULL;

	return e;
}

OSErr estimate_finish(FormatRecordPtr pb, intptr_t *data){
	
	// estimate how large we expect the file will be
	pb->minDataBytes =
		SIZEOF_FILE_HEADER
		+ SIZEOF_BLOCK_HEADER + 46 /* general image attributes */
		+ (pb->imageMode == plugInModeIndexedColor) * (SIZEOF_BLOCK_HEADER + 8 + sizeof(RGBQUAD)*256) /* optional palette */
		+ SIZEOF_BLOCK_HEADER /* layer start block */
			/* first layer */
			+ SIZEOF_BLOCK_HEADER /* layer block */
				+ SIZEOF_LAYER_INFO_CHUNK
				+ 8 /* layer bitmap chunk */
		+ pb->planes*( SIZEOF_BLOCK_HEADER + 28 /* channel info */ ) ;

	pb->maxDataBytes = pb->minDataBytes + pb->planes * G->channelsize;

	pb->minRsrcBytes = pb->maxRsrcBytes = 0;

	return noErr;
}