/* Copyright (C) 2001-2006 Artifex Software, Inc.
   All Rights Reserved.
  
   This software is provided AS-IS with no warranty, either express or
   implied.

   This software is distributed under license and may not be copied, modified
   or distributed except as expressly authorized under the terms of that
   license.  Refer to licensing information at http://www.artifex.com/
   or contact Artifex Software, Inc.,  7 Mt. Lassen Drive - Suite A-134,
   San Rafael, CA  94903, U.S.A., +1(415)492-9861, for further information.
*/

/* $Id: gscolor2.c 8022 2007-06-05 22:23:38Z giles $ */
/* Level 2 color operators for Ghostscript library */
#include "memory_.h"
#include "gx.h"
#include "gserrors.h"
#include "gxarith.h"
#include "gxfixed.h"		/* ditto */
#include "gxmatrix.h"		/* for gzstate.h */
#include "gxcspace.h"		/* for gscolor2.h */
#include "gxcolor2.h"
#include "gzstate.h"
#include "gxpcolor.h"
#include "stream.h"

/* ---------------- General colors and color spaces ---------------- */

/* setcolorspace */
int
gs_setcolorspace(gs_state * pgs, gs_color_space * pcs)
{
    int             code = 0;
    gs_color_space  *cs_old = pgs->color_space;
    gs_client_color cc_old = *pgs->ccolor;

    if (pgs->in_cachedevice)
	return_error(gs_error_undefined);

    if (pcs->id != pgs->color_space->id) {
        rc_increment(pcs);
        pgs->color_space = pcs;
        if ( (code = pcs->type->install_cspace(pcs, pgs)) < 0          ||
              (pgs->overprint && (code = gs_do_set_overprint(pgs)) < 0)  ) {
            pgs->color_space = cs_old;
            rc_decrement_only(pcs, "gs_setcolorspace");
        } else {
	    cs_old->type->adjust_color_count(&cc_old, cs_old, -1);
	    rc_decrement_only(cs_old, "gs_setcolorspace");
	}
    }

    if (code >= 0) {
	pgs->color_space->pclient_color_space_data =
	    pcs->pclient_color_space_data;
        cs_full_init_color(pgs->ccolor, pcs);
        gx_unset_dev_color(pgs);
    }

    return code;
}

/* currentcolorspace */
gs_color_space *
gs_currentcolorspace(const gs_state * pgs)
{
    return pgs->color_space;
}

/* setcolor */
int
gs_setcolor(gs_state * pgs, const gs_client_color * pcc)
{
    gs_color_space *    pcs = pgs->color_space;
    gs_client_color     cc_old = *pgs->ccolor;

   if (pgs->in_cachedevice)
	return_error(gs_error_undefined); /* PLRM3 page 215. */
    gx_unset_dev_color(pgs);
    (*pcs->type->adjust_color_count)(pcc, pcs, 1);
    *pgs->ccolor = *pcc;
    (*pcs->type->restrict_color)(pgs->ccolor, pcs);
    (*pcs->type->adjust_color_count)(&cc_old, pcs, -1);

    return 0;
}

/* currentcolor */
const gs_client_color *
gs_currentcolor(const gs_state * pgs)
{
    return pgs->ccolor;
}

/* ------ Internal procedures ------ */

/* GC descriptors */
private_st_indexed_map();

/* Define a lookup_index procedure that just returns the map values. */
int
lookup_indexed_map(const gs_color_space * pcs, int index, float *values)
{
    int m = cs_num_components(pcs->base_space);
    const float *pv = &pcs->params.indexed.lookup.map->values[index * m];

    memcpy(values, pv, sizeof(*values) * m);
    return 0;
}

/* Free an indexed map and its values when the reference count goes to 0. */
void
free_indexed_map(gs_memory_t * pmem, void *pmap, client_name_t cname)
{
    gs_free_object(pmem, ((gs_indexed_map *) pmap)->values, cname);
    gs_free_object(pmem, pmap, cname);
}

/*
 * Allocate an indexed map for an Indexed or Separation color space.
 */
int
alloc_indexed_map(gs_indexed_map ** ppmap, int nvals, gs_memory_t * pmem,
		  client_name_t cname)
{
    gs_indexed_map *pimap;

    rc_alloc_struct_1(pimap, gs_indexed_map, &st_indexed_map, pmem,
		      return_error(gs_error_VMerror), cname);
    if (nvals > 0) {
	pimap->values =
	    (float *)gs_alloc_byte_array(pmem, nvals, sizeof(float), cname);

	if (pimap->values == 0) {
	    gs_free_object(pmem, pimap, cname);
	    return_error(gs_error_VMerror);
	}
    } else
	pimap->values = 0;
    pimap->rc.free = free_indexed_map;
    pimap->proc_data = 0;	/* for GC */
    pimap->num_values = nvals;
    *ppmap = pimap;
    return 0;
}

/* ---------------- Indexed color spaces ---------------- */

gs_private_st_composite(st_color_space_Indexed, gs_color_space,
     "gs_color_space_Indexed", cs_Indexed_enum_ptrs, cs_Indexed_reloc_ptrs);

/* ------ Color space ------ */

/* Define the Indexed color space type. */
private cs_proc_restrict_color(gx_restrict_Indexed);
private cs_proc_concrete_space(gx_concrete_space_Indexed);
private cs_proc_concretize_color(gx_concretize_Indexed);
private cs_proc_install_cspace(gx_install_Indexed);
private cs_proc_set_overprint(gx_set_overprint_Indexed);
private cs_proc_final(gx_final_Indexed);
private cs_proc_serialize(gx_serialize_Indexed);
const gs_color_space_type gs_color_space_type_Indexed = {
    gs_color_space_index_Indexed, false, false,
    &st_color_space_Indexed, gx_num_components_1,
    gx_init_paint_1, gx_restrict_Indexed,
    gx_concrete_space_Indexed,
    gx_concretize_Indexed, NULL,
    gx_default_remap_color, gx_install_Indexed,
    gx_set_overprint_Indexed,
    gx_final_Indexed, gx_no_adjust_color_count,
    gx_serialize_Indexed,
    gx_cspace_is_linear_default
};

/* GC procedures. */

private uint
indexed_table_size(const gs_color_space *pcs)
{
    return (pcs->params.indexed.hival + 1) * pcs->params.indexed.n_comps;
}
private 
ENUM_PTRS_WITH(cs_Indexed_enum_ptrs, gs_color_space *pcs) return 0;
case 0:
if (pcs->params.indexed.use_proc)
    ENUM_RETURN((void *)pcs->params.indexed.lookup.map);
else
    return ENUM_CONST_STRING2(pcs->params.indexed.lookup.table.data,
			      indexed_table_size(pcs));
ENUM_PTRS_END
private RELOC_PTRS_WITH(cs_Indexed_reloc_ptrs, gs_color_space *pcs)
{
    if (pcs->params.indexed.use_proc)
	RELOC_PTR(gs_color_space, params.indexed.lookup.map);
    else {
	gs_const_string table;

	table.data = pcs->params.indexed.lookup.table.data;
	table.size = indexed_table_size(pcs);
	RELOC_CONST_STRING_VAR(table);
	pcs->params.indexed.lookup.table.data = table.data;
    }
}
RELOC_PTRS_END


/* Color space installation for an Indexed color space. */

private int
gx_install_Indexed(gs_color_space * pcs, gs_state * pgs)
{
    return (*pcs->base_space->type->install_cspace)
	(pcs->base_space, pgs);
}

/* Color space overprint setting ditto. */

private int
gx_set_overprint_Indexed(const gs_color_space * pcs, gs_state * pgs)
{
    return (*pcs->base_space->type->set_overprint)
	((const gs_color_space *)pcs->base_space, pgs);
}

/* Color space finalization ditto. */

private void
gx_final_Indexed(const gs_color_space * pcs)
{
    if (pcs->params.indexed.use_proc) {
	rc_adjust_const(pcs->params.indexed.lookup.map, -1,
			"gx_adjust_Indexed");
    }
}

/*
 * Default palette mapping functions for indexed color maps. These just
 * return the values already in the palette.
 *
 * For performance reasons, we provide four functions: special cases for 1,
 * 3, and 4 entry palettes, and a general case. Note that these procedures
 * do not range-check their input values.
 */
private int
map_palette_entry_1(const gs_color_space * pcs, int indx, float *values)
{
    values[0] = pcs->params.indexed.lookup.map->values[indx];
    return 0;
}

private int
map_palette_entry_3(const gs_color_space * pcs, int indx, float *values)
{
    const float *pv = &(pcs->params.indexed.lookup.map->values[3 * indx]);

    values[0] = pv[0];
    values[1] = pv[1];
    values[2] = pv[2];
    return 0;
}

private int
map_palette_entry_4(const gs_color_space * pcs, int indx, float *values)
{
    const float *pv = &(pcs->params.indexed.lookup.map->values[4 * indx]);

    values[0] = pv[0];
    values[1] = pv[1];
    values[2] = pv[2];
    values[3] = pv[3];
    return 0;
}

private int
map_palette_entry_n(const gs_color_space * pcs, int indx, float *values)
{
    int m = cs_num_components(pcs->base_space);

    memcpy((void *)values,
	   (const void *)(pcs->params.indexed.lookup.map->values + indx * m),
	   m * sizeof(float)
    );

    return 0;
}

/*
 * Allocate an indexed map to be used as a palette for indexed color space.
 */
private gs_indexed_map *
alloc_indexed_palette(
			 const gs_color_space * pbase_cspace,
			 int nvals,
			 gs_memory_t * pmem
)
{
    int num_comps = gs_color_space_num_components(pbase_cspace);
    gs_indexed_map *pimap;
    int code =
    alloc_indexed_map(&pimap, nvals * num_comps, pmem,
		      "alloc_indexed_palette");

    if (code < 0)
	return 0;
    if (num_comps == 1)
	pimap->proc.lookup_index = map_palette_entry_1;
    else if (num_comps == 3)
	pimap->proc.lookup_index = map_palette_entry_3;
    else if (num_comps == 4)
	pimap->proc.lookup_index = map_palette_entry_4;
    else
	pimap->proc.lookup_index = map_palette_entry_n;
    return pimap;
}

/*
 * Build an indexed color space.
 */
int
gs_cspace_build_Indexed(
			   gs_color_space ** ppcspace,
			   gs_color_space * pbase_cspace,
			   uint num_entries,
			   const gs_const_string * ptbl,
			   gs_memory_t * pmem
)
{
    gs_color_space *pcspace = 0;
    gs_indexed_params *pindexed = 0;

    if ((pbase_cspace == 0) || !pbase_cspace->type->can_be_base_space)
	return_error(gs_error_rangecheck);

    pcspace = gs_cspace_alloc(pmem, &gs_color_space_type_Indexed);
    if (pcspace == NULL)
	return_error(gs_error_VMerror);
    pindexed = &(pcspace->params.indexed);
    if (ptbl == 0) {
	pindexed->lookup.map =
	    alloc_indexed_palette(pbase_cspace, num_entries, pmem);
	if (pindexed->lookup.map == 0) {
	    gs_free_object(pmem, pcspace, "gs_cspace_build_Indexed");
	    return_error(gs_error_VMerror);
	}
	pindexed->use_proc = true;
    } else {
	pindexed->lookup.table = *ptbl;
	pindexed->use_proc = false;
    }
    pcspace->base_space = pbase_cspace;
    rc_increment(pbase_cspace);
    pindexed->hival = num_entries - 1;
    pindexed->n_comps = cs_num_components(pbase_cspace);
    *ppcspace = pcspace;
    return 0;
}

/*
 * Return the number of entries in an indexed color space.
 */
int
gs_cspace_indexed_num_entries(const gs_color_space * pcspace)
{
    if (gs_color_space_get_index(pcspace) != gs_color_space_index_Indexed)
	return 0;
    return pcspace->params.indexed.hival + 1;
}

/*
 * Get the palette for an indexed color space. This will return a null
 * pointer if the color space is not an indexed color space or if the
 * color space does not use the mapped index palette.
 */
float *
gs_cspace_indexed_value_array(const gs_color_space * pcspace)
{
    if ((gs_color_space_get_index(pcspace) != gs_color_space_index_Indexed) ||
	pcspace->params.indexed.use_proc
	)
	return 0;
    return pcspace->params.indexed.lookup.map->values;
}

/*
 * Set the lookup procedure to be used with an indexed color space.
 */
int
gs_cspace_indexed_set_proc(
			   gs_color_space * pcspace,
			   int (*proc)(const gs_color_space *, int, float *)
)
{
    if ((gs_color_space_get_index(pcspace) != gs_color_space_index_Indexed) ||
	!pcspace->params.indexed.use_proc
	)
	return_error(gs_error_rangecheck);
    pcspace->params.indexed.lookup.map->proc.lookup_index = proc;
    return 0;
}

/* ------ Colors ------ */

/* Force an Indexed color into legal range. */
private void
gx_restrict_Indexed(gs_client_color * pcc, const gs_color_space * pcs)
{
    float value = pcc->paint.values[0];

    pcc->paint.values[0] =
	(is_fneg(value) ? 0 :
	 value >= pcs->params.indexed.hival ? pcs->params.indexed.hival :
	 value);
}

/* Color remapping for Indexed color spaces. */
private const gs_color_space *
gx_concrete_space_Indexed(const gs_color_space * pcs,
			  const gs_imager_state * pis)
{
    return cs_concrete_space(pcs->base_space, pis);
}

private int
gx_concretize_Indexed(const gs_client_color * pc, const gs_color_space * pcs,
		      frac * pconc, const gs_imager_state * pis)
{
    float value = pc->paint.values[0];
    int index =
	(is_fneg(value) ? 0 :
	 value >= pcs->params.indexed.hival ? pcs->params.indexed.hival :
	 (int)value);
    const gs_color_space *pbcs =
	(const gs_color_space *)pcs->base_space;
    gs_client_color cc;
    int code = gs_cspace_indexed_lookup(pcs, index, &cc);

    if (code < 0)
	return code;
    return (*pbcs->type->concretize_color) (&cc, pbcs, pconc, pis);
}

/* Look up an index in an Indexed color space. */
int
gs_cspace_indexed_lookup(const gs_color_space *pcs, int index,
			 gs_client_color *pcc)
{
    const gs_indexed_params *pip = &pcs->params.indexed;
    if (pip->use_proc) {
	return pip->lookup.map->proc.lookup_index
	    (pcs, index, &pcc->paint.values[0]);
    } else {
	const gs_color_space *pbcs = pcs->base_space;
	int m = cs_num_components(pbcs);
	const byte *pcomp = pip->lookup.table.data + m * index;

	switch (m) {
	    default: {		/* DeviceN */
		int i;

		for (i = 0; i < m; ++i)
		    pcc->paint.values[i] = pcomp[i] * (1.0 / 255.0);
	    }
		break;
	    case 4:
		pcc->paint.values[3] = pcomp[3] * (1.0 / 255.0);
	    case 3:
		pcc->paint.values[2] = pcomp[2] * (1.0 / 255.0);
	    case 2:
		pcc->paint.values[1] = pcomp[1] * (1.0 / 255.0);
	    case 1:
		pcc->paint.values[0] = pcomp[0] * (1.0 / 255.0);
	}
	return 0;
    }
}

/* ---------------- Serialization. -------------------------------- */

private int 
gx_serialize_Indexed(const gs_color_space * pcs, stream * s)
{
    const gs_indexed_params * p = &pcs->params.indexed;
    uint n;
    int code = gx_serialize_cspace_type(pcs, s);

    if (code < 0)
	return code;
    code = cs_serialize(pcs->base_space, s);
    if (code < 0)
	return code;
    code = sputs(s, (const byte *)&p->hival, sizeof(p->hival), &n);
    if (code < 0)
	return code;
    code = sputs(s, (const byte *)&p->use_proc, sizeof(p->use_proc), &n);
    if (code < 0)
	return code;
    if (p->use_proc) {
	code = sputs(s, (const byte *)&p->lookup.map->num_values, 
		sizeof(p->lookup.map->num_values), &n);
	if (code < 0)
	    return code;
	code = sputs(s, (const byte *)&p->lookup.map->values[0], 
		sizeof(p->lookup.map->values[0]) * p->lookup.map->num_values, &n);
    } else {
	code = sputs(s, (const byte *)&p->lookup.table.size, 
			sizeof(p->lookup.table.size), &n);
	if (code < 0)
	    return code;
	code = sputs(s, p->lookup.table.data, p->lookup.table.size, &n);
    }
    return code;
}

/* ---------------- High level device support -------------------------------- */

/*
 * This special function forces a device to include the current
 * color space into the output. Returns 'rangecheck' if the device can't handle it.
 * The primary reason is to include DefaultGray, DefaultRGB, DefaultCMYK into PDF.
 * Should be called for each page that requires the resource.
 * Redundant calls per page with same cspace id are allowed.
 * Redundant calls per page with different cspace id are are allowed but 
 * highly undesirable.
 * No need to call it with color spaces explicitly referred by the document,
 * because they are included automatically.
 * res_name and name_length passes the resource name.
 */
int
gs_includecolorspace(gs_state * pgs, const byte *res_name, int name_length)
{
    return (*dev_proc(pgs->device, include_color_space))(pgs->device, pgs->color_space, res_name, name_length);
}