/* Copyright (C) 1995, 2000 artofcode LLC.  All rights reserved.
  
  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.

*/

/*$Id: zfzlib.c,v 1.3.6.1.2.1 2003/01/17 00:49:06 giles Exp $ */
/* zlib and Flate filter creation */
#include "ghost.h"
#include "oper.h"
#include "idict.h"
#include "strimpl.h"
#include "spdiffx.h"
#include "spngpx.h"
#include "szlibx.h"
#include "idparam.h"
#include "ifilter.h"
#include "ifrpred.h"
#include "ifwpred.h"

/* Common setup for zlib (Flate) filter */
private int
filter_zlib(i_ctx_t *i_ctx_p, stream_zlib_state *pzls)
{
    os_ptr op = osp;
    int code = 0;

    (*s_zlibE_template.set_defaults)((stream_state *)pzls);
    if (r_has_type(op, t_dictionary))
	code = dict_int_param(op, "Effort", -1, 9, -1, &pzls->level);
    return code;
}

/* <source> zlibEncode/filter <file> */
/* <source> <dict> zlibEncode/filter <file> */
private int
zzlibE(i_ctx_t *i_ctx_p)
{
    stream_zlib_state zls;
    int code = filter_zlib(i_ctx_p, &zls);

    if (code < 0)
	return code;
    return filter_write(i_ctx_p, 0, &s_zlibE_template, (stream_state *)&zls, 0);
}

/* <target> zlibDecode/filter <file> */
/* <target> <dict> zlibDecode/filter <file> */
private int
zzlibD(i_ctx_t *i_ctx_p)
{
    stream_zlib_state zls;

    (*s_zlibD_template.set_defaults)((stream_state *)&zls);
    return filter_read(i_ctx_p, 0, &s_zlibD_template, (stream_state *)&zls, 0);
}

/* <source> FlateEncode/filter <file> */
/* <source> <dict> FlateEncode/filter <file> */
private int
zFlateE(i_ctx_t *i_ctx_p)
{
    stream_zlib_state zls;
    int code = filter_zlib(i_ctx_p, &zls);

    if (code < 0)
	return code;
    return filter_write_predictor(i_ctx_p, 0, &s_zlibE_template,
				  (stream_state *)&zls);
}

/* <target> FlateDecode/filter <file> */
/* <target> <dict> FlateDecode/filter <file> */
private int
zFlateD(i_ctx_t *i_ctx_p)
{
    stream_zlib_state zls;

    (*s_zlibD_template.set_defaults)((stream_state *)&zls);
    return filter_read_predictor(i_ctx_p, 0, &s_zlibD_template,
				 (stream_state *)&zls);
}

/* ------ Initialization procedure ------ */

const op_def zfzlib_op_defs[] =
{
    op_def_begin_filter(),
    {"1zlibEncode", zzlibE},
    {"1zlibDecode", zzlibD},
    {"1FlateEncode", zFlateE},
    {"1FlateDecode", zFlateD},
    op_def_end(0)
};