/* Copyright (C) 2001-2006 Artifex Software, Inc.
   All Rights Reserved.
  
  This file is part of GNU ghostscript

  GNU ghostscript is free software; you can redistribute it and/or
  modify it under the terms of the version 2 of the GNU General Public
  License as published by the Free Software Foundation.

  GNU ghostscript 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
  ghostscript; see the file COPYING. If not, write to the Free Software Foundation,
  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

*/

/* $Id: zcsindex.c,v 1.10 2008/03/23 15:27:51 Arabidopsis Exp $ */
/* Indexed color space support */
#include "memory_.h"
#include "ghost.h"
#include "oper.h"
#include "gsstruct.h"
#include "gscolor.h"
#include "gsmatrix.h"		/* for gxcolor2.h */
#include "gxcspace.h"
#include "gxfixed.h"		/* ditto */
#include "gxcolor2.h"
#include "estack.h"
#include "ialloc.h"
#include "icsmap.h"
#include "igstate.h"
#include "ivmspace.h"
#include "store.h"

/* Imported from gscolor2.c */
extern const gs_color_space_type gs_color_space_type_Indexed;

/* Forward references. */
static int indexed_map1(i_ctx_t *);

/* <array> .setindexedspace - */
/* The current color space is the base space for the indexed space. */
static int
zsetindexedspace(i_ctx_t *i_ctx_p)
{
    os_ptr op = osp;
    ref *pproc = &istate->colorspace.procs.special.index_proc;
    const ref *pcsa;
    gs_color_space *pcs;
    gs_color_space *pcs_base;
    ref_colorspace cspace_old;
    uint edepth = ref_stack_count(&e_stack);
    int num_entries;
    int code;

    check_read_type(*op, t_array);
    if (r_size(op) != 4)
	return_error(e_rangecheck);
    pcsa = op->value.const_refs + 1;
    check_type_only(pcsa[1], t_integer);
    if (pcsa[1].value.intval < 0 || pcsa[1].value.intval > 4095)
	return_error(e_rangecheck);
    num_entries = (int)pcsa[1].value.intval + 1;
    pcs_base = gs_currentcolorspace(igs);
    if (!pcs_base->type->can_be_base_space)
	return_error(e_rangecheck);
    cspace_old = istate->colorspace;

    if (r_has_type(&pcsa[2], t_string)) {
	int num_values = num_entries * cs_num_components(pcs_base);

	check_read(pcsa[2]);
	/*
	 * The PDF and PS specifications state that the lookup table must have
	 * the exact number of of data bytes needed.  However we have found
	 * PDF files from Amyuni with extra data bytes.  Acrobat 6.0 accepts
	 * these files without complaint, so we ignore the extra data.
	 */
	if (r_size(&pcsa[2]) < num_values)
	    return_error(e_rangecheck);
	pcs = gs_cspace_alloc(imemory, &gs_color_space_type_Indexed);
	pcs->base_space = pcs_base;
	rc_increment(pcs_base);
	pcs->params.indexed.lookup.table.data = pcsa[2].value.const_bytes;
	pcs->params.indexed.lookup.table.size = num_values;
	pcs->params.indexed.use_proc = 0;
	make_null(pproc);
	code = 0;
    } else {
	gs_indexed_map *map;

	check_proc(pcsa[2]);
	/*
	 * We have to call zcs_begin_map before moving the parameters,
	 * since if the color space is a DeviceN or Separation space,
	 * the memmove will overwrite its parameters.
	 */
	code = zcs_begin_map(i_ctx_p, &map, &pcsa[2], num_entries,
			     pcs_base, indexed_map1);
	if (code < 0)
	    return code;
	pcs = gs_cspace_alloc(imemory, &gs_color_space_type_Indexed);
	pcs->base_space = pcs_base;
	rc_increment(pcs_base);
	pcs->params.indexed.use_proc = 1;
	*pproc = pcsa[2];
	map->proc.lookup_index = lookup_indexed_map;
	pcs->params.indexed.lookup.map = map;
    }
    pcs->params.indexed.hival = num_entries - 1;
    pcs->params.indexed.n_comps = cs_num_components(pcs_base);
    code = gs_setcolorspace(igs, pcs);
    /* release reference from construction */
    rc_decrement_only(pcs, "zsetindexedspace");
    if (code < 0) {
	istate->colorspace = cspace_old;
	ref_stack_pop_to(&e_stack, edepth);
	return code;
    }
    pop(1);
    return (ref_stack_count(&e_stack) == edepth ? 0 : o_push_estack);	/* installation will load the caches */
}

/* Continuation procedure for saving mapped Indexed color values. */
static int
indexed_map1(i_ctx_t *i_ctx_p)
{
    os_ptr op = osp;
    es_ptr ep = esp;
    int i = (int)ep[csme_index].value.intval;

    if (i >= 0) {		/* i.e., not first time */
	int m = (int)ep[csme_num_components].value.intval;
	int code = float_params(op, m, &r_ptr(&ep[csme_map], gs_indexed_map)->values[i * m]);

	if (code < 0)
	    return code;
	pop(m);
	op -= m;
	if (i == (int)ep[csme_hival].value.intval) {	/* All done. */
	    esp -= num_csme;
	    return o_pop_estack;
	}
    }
    push(1);
    ep[csme_index].value.intval = ++i;
    make_int(op, i);
    make_op_estack(ep + 1, indexed_map1);
    ep[2] = ep[csme_proc];	/* lookup proc */
    esp = ep + 2;
    return o_push_estack;
}

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

const op_def zcsindex_l2_op_defs[] =
{
    op_def_begin_level2(),
    {"1.setindexedspace", zsetindexedspace},
		/* Internal operators */
    {"1%indexed_map1", indexed_map1},
    op_def_end(0)
};

/* ------ Internal routines ------ */

/* Allocate, and prepare to load, the index or tint map. */
int
zcs_begin_map(i_ctx_t *i_ctx_p, gs_indexed_map ** pmap, const ref * pproc,
	      int num_entries,  const gs_color_space * base_space,
	      op_proc_t map1)
{
    gs_memory_t *mem = gs_state_memory(igs);
    int space = imemory_space((gs_ref_memory_t *)mem);
    int num_components = cs_num_components(base_space);
    int num_values = num_entries * num_components;
    gs_indexed_map *map;
    int code = alloc_indexed_map(&map, num_values, mem,
				 "setcolorspace(mapped)");
    es_ptr ep;

    if (code < 0)
	return code;
    *pmap = map;
    /* Map the entire set of color indices.  Since the */
    /* o-stack may not be able to hold N*4096 values, we have */
    /* to load them into the cache as they are generated. */
    check_estack(num_csme + 1);	/* 1 extra for map1 proc */
    ep = esp += num_csme;
    make_int(ep + csme_num_components, num_components);
    make_struct(ep + csme_map, space, map);
    ep[csme_proc] = *pproc;
    make_int(ep + csme_hival, num_entries - 1);
    make_int(ep + csme_index, -1);
    push_op_estack(map1);
    return o_push_estack;
}
