/* Copyright (C) 2001-2023 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 the license contained in the file LICENSE in this distribution.

   Refer to licensing information at http://www.artifex.com or contact
   Artifex Software, Inc.,  39 Mesa Street, Suite 108A, San Francisco,
   CA 94129, USA, for further information.
*/


/* ImageType 1 initialization */
#include "gx.h"
#include "gserrors.h"
#include "gxiparam.h"
#include "gximage.h"
#include "stream.h"
#include "memory_.h"

/* Structure descriptor */
public_st_gs_image1();

/*
 * Define the image types for ImageType 1 images.
 * Note that opaque images and masks have different types, although
 * they have the same ImageType.
 */
static image_proc_sput(gx_image1_sput);
static image_proc_sget(gx_image1_sget);
static image_proc_release(gx_image1_release);
const gx_image_type_t gs_image_type_1 = {
    &st_gs_image1, gx_begin_image1,
    gx_image1_sput, gx_image1_sget, gx_image1_release, 1
};
static image_proc_sput(gx_image1_mask_sput);
static image_proc_sget(gx_image1_mask_sget);
/*
 * Image masks are not actually pixel images, so they don't need to
 * worry about releasing the color space.
 */
const gx_image_type_t gs_image_type_mask1 = {
    &st_gs_image1, gx_begin_image1,
    gx_image1_mask_sput, gx_image1_mask_sget, gx_image_default_release, 1
};

/* Define the procedures for initializing gs_image_ts to default values. */
void
gs_image_t_init_adjust(gs_image_t * pim, gs_color_space * color_space,
                       bool adjust)
{
    gs_pixel_image_t_init((gs_pixel_image_t *) pim, color_space);
    pim->ImageMask = (color_space == NULL);
    pim->adjust = adjust;
    pim->type = (pim->ImageMask ? &gs_image_type_mask1 : &gs_image_type_1);
    pim->Alpha = gs_image_alpha_none;
    pim->image_parent_type = gs_image_type1;
    pim->imagematrices_are_untrustworthy = 0;
}
void
gs_image_t_init_mask_adjust(gs_image_t * pim, bool write_1s, bool adjust)
{
    gs_image_t_init(pim, NULL);
    if (write_1s)
        pim->Decode[0] = 1, pim->Decode[1] = 0;
    else
        pim->Decode[0] = 0, pim->Decode[1] = 1;
    pim->adjust = adjust;
}

/* Start processing an ImageType 1 image. */
int
gx_begin_image1(gx_device * dev,
                const gs_gstate * pgs, const gs_matrix * pmat,
                const gs_image_common_t * pic, const gs_int_rect * prect,
                const gx_drawing_color * pdcolor, const gx_clip_path * pcpath,
                gs_memory_t * mem, gx_image_enum_common_t ** pinfo)
{
    gx_image_enum *penum;
    const gs_image_t *pim = (const gs_image_t *)pic;
    int code = gx_image_enum_alloc(pic, prect, mem, &penum);

    if (code < 0)
        return code;
    penum->alpha = pim->Alpha;
    penum->use_mask_color = false;
    penum->image_parent_type = pim->image_parent_type;
    penum->masked = pim->ImageMask;
    penum->adjust =
        (pim->ImageMask && pim->adjust ? float2fixed(0.25) : fixed_0);
    code = gx_image_enum_begin(dev, pgs, pmat, pic, pdcolor, pcpath, mem,
                               penum);
    if (code >= 0)
        *pinfo = (gx_image_enum_common_t *)penum;
    else {
        /* penum is freed in by gx_image_enum_begin */
        *pinfo = NULL;
    }
    return code;
}

/* Serialization */

/*
 * We add the Alpha value to the control word.
 */

static int
gx_image1_sput(const gs_image_common_t *pic, stream *s,
               const gs_color_space **ppcs)
{
    const gs_image_t *const pim = (const gs_image_t *)pic;

    return gx_pixel_image_sput((const gs_pixel_image_t *)pic, s, ppcs,
                               (int)pim->Alpha);
}

static int
gx_image1_sget(gs_image_common_t *pic, stream *s,
               gs_color_space *pcs)
{
    gs_image1_t *const pim = (gs_image1_t *)pic;
    int code = gx_pixel_image_sget((gs_pixel_image_t *)pim, s, pcs);

    if (code < 0)
        return code;
    pim->type = &gs_image_type_1;
    pim->ImageMask = false;
    pim->Alpha = code;
    pim->image_parent_type = gs_image_type1;
    return 0;
}

/*
 * Masks have different parameters, so we use a different encoding:
 *	FFFFEEDCBA
 *	    A = 0 if standard ImageMatrix, 1 if explicit ImageMatrix
 *	    B = 0 if Decode=[0 1], 1 if Decode=[1 0]
 *	    C = Interpolate
 *	    D = adjust
 *	    EE = Alpha
 *	    FFFF = BitsPerComponent - 1 (only needed for soft masks)
 *	Width, encoded as a variable-length uint
 *	Height, encoded like Width
 *	ImageMatrix (if A = 1), per gs_matrix_store/fetch
 */
#define MI_ImageMatrix 0x01
#define MI_Decode 0x02
#define MI_Interpolate 0x04
#define MI_adjust 0x08
#define MI_Alpha_SHIFT 4
#define MI_Alpha_MASK 0x3
#define MI_BPC_SHIFT 6
#define MI_BPC_MASK 0xf
#define MI_BITS 10

static int
gx_image1_mask_sput(const gs_image_common_t *pic, stream *s,
                    const gs_color_space **ignore_ppcs)
{
    const gs_image_t *pim = (const gs_image_t *)pic;
    uint control =
        (gx_image_matrix_is_default((const gs_data_image_t *)pim) ? 0 :
         MI_ImageMatrix) |
        (pim->Decode[0] != 0 ? MI_Decode : 0) |
        (pim->Interpolate ? MI_Interpolate : 0) |
        (pim->adjust ? MI_adjust : 0) |
        (pim->Alpha << MI_Alpha_SHIFT) |
        ((pim->BitsPerComponent - 1) << MI_BPC_SHIFT);

    sput_variable_uint(s, control);
    sput_variable_uint(s, (uint)pim->Width);
    sput_variable_uint(s, (uint)pim->Height);
    if (control & MI_ImageMatrix)
        sput_matrix(s, &pim->ImageMatrix);
    return 0;
}

static int
gx_image1_mask_sget(gs_image_common_t *pic, stream *s,
                    gs_color_space *ignore_pcs)
{
    gs_image1_t *const pim = (gs_image1_t *)pic;
    int code;
    uint control;

    if ((code = sget_variable_uint(s, &control)) < 0)
        return code;
    gs_image_t_init_mask(pim, (control & MI_Decode) != 0);
    if ((code = sget_variable_uint(s, (uint *)&pim->Width)) < 0 ||
        (code = sget_variable_uint(s, (uint *)&pim->Height)) < 0
        )
        return code;
    if (control & MI_ImageMatrix) {
        if ((code = sget_matrix(s, &pim->ImageMatrix)) < 0)
            return code;
    } else
        gx_image_matrix_set_default((gs_data_image_t *)pim);
    pim->Interpolate = (control & MI_Interpolate) != 0;
    pim->adjust = (control & MI_adjust) != 0;
    pim->Alpha = (control >> MI_Alpha_SHIFT) & MI_Alpha_MASK;
    pim->BitsPerComponent = ((control >> MI_BPC_SHIFT) & MI_BPC_MASK) + 1;
    return 0;
}

static void
gx_image1_release(gs_image_common_t *pic, gs_memory_t *mem)
{
    gx_pixel_image_release((gs_pixel_image_t *)pic, mem);
}

/* Free the image enumerator. */
void
gx_image_free_enum(gx_image_enum_common_t **ppenum)
{
    gx_image_enum_common_t  * penum = *ppenum;
    gs_memory_t *mem = penum->memory;

     /* Bug 688845 comment #38 :
        Adobe Illustrator creates a Postscript document,
        in which an image data procedure executes 'save',
        and the corresponding 'restore' appears after the image end.
        It causes this procedure is called at a higher save level than
        at which the enumerator was allocated, so that gs_free_object below
        works idle. Nevertheless we can't leave pointers in the structure,
        because they may point to blocks already released
        by the client's subclass method for end_image.
        Leaving them uncleaned caused a real crash in the garbager - see bug 688845.
        So we clean the entire subclassed enumerator here,
        rather this is a generic function for base class.
        Note the cleaning is neccessaryfor Postscript only,
        because other languaged don't implement save-restore.
     */
    memset(penum, 0, gs_object_size(mem, penum));
    gs_free_object(mem, penum, "gx_image_free_enum");
    *ppenum = NULL;
}