// Copyright (C) 2004-2021 Artifex Software, Inc.

//

// This file is part of MuPDF.

//

// MuPDF is free software: you can redistribute it and/or modify it under the

// terms of the GNU Affero General Public License as published by the Free

// Software Foundation, either version 3 of the License, or (at your option)

// any later version.

//

// MuPDF 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 Affero General Public License for more

// details.

//

// You should have received a copy of the GNU Affero General Public License

// along with MuPDF. If not, see <https://www.gnu.org/licenses/agpl-3.0.en.html>

//

// Alternative licensing terms are available from the licensor.

// For commercial licensing, see <https://www.artifex.com/> or contact

// Artifex Software, Inc., 39 Mesa Street, Suite 108A, San Francisco,

// CA 94129, USA, for further information.

#include "mupdf/fitz.h"

#include <string.h>

#include <limits.h>

const char *fz_pclm_write_options_usage =

  "PCLm output options:\n"

  "\tcompression=none: No compression (default)\n"

  "\tcompression=flate: Flate compression\n"

  "\tstrip-height=N: Strip height (default 16)\n"

  "\n";

fz_pclm_options *

fz_parse_pclm_options(fz_context *ctx, fz_pclm_options *opts, const char *args)

{

  const char *val;

  memset(opts, 0, sizeof *opts);

  if (fz_has_option(ctx, args, "compression", &val))

  {

    if (fz_option_eq(val, "none"))

      opts->compress = 0;

    else if (fz_option_eq(val, "flate"))

      opts->compress = 1;

    else

      fz_throw(ctx, FZ_ERROR_ARGUMENT, "Unsupported PCLm compression %s (none, or flate only)", val);

  }

  if (fz_has_option(ctx, args, "strip-height", &val))

  {

    int i = fz_atoi(val);

    if (i <= 0)

      fz_throw(ctx, FZ_ERROR_ARGUMENT, "Unsupported PCLm strip height %d (suggest 16)", i);

    opts->strip_height = i;

  }

  return opts;

}

void

fz_write_pixmap_as_pclm(fz_context *ctx, fz_output *out, const fz_pixmap *pixmap, const fz_pclm_options *pclm)

{

  fz_band_writer *writer;

  if (!pixmap || !out)

    return;

  writer = fz_new_pclm_band_writer(ctx, out, pclm);

  fz_try(ctx)

  {

    fz_write_header(ctx, writer, pixmap->w, pixmap->h, pixmap->n, pixmap->alpha, pixmap->xres, pixmap->yres, 0, pixmap->colorspace, pixmap->seps);

    fz_write_band(ctx, writer, pixmap->stride, pixmap->h, pixmap->samples);

    fz_close_band_writer(ctx, writer);

  }

  fz_always(ctx)

    fz_drop_band_writer(ctx, writer);

  fz_catch(ctx)

    fz_rethrow(ctx);

}

typedef struct pclm_band_writer_s

{

  fz_band_writer super;

  fz_pclm_options options;

  int obj_num;

  int xref_max;

  int64_t *xref;

  int pages;

  int page_max;

  int *page_obj;

  unsigned char *stripbuf;

  unsigned char *compbuf;

  size_t complen;

} pclm_band_writer;

static int

new_obj(fz_context *ctx, pclm_band_writer *writer)

{

  int64_t pos = fz_tell_output(ctx, writer->super.out);

  if (writer->obj_num >= writer->xref_max)

  {

    int new_max = writer->xref_max * 2;

    if (new_max < writer->obj_num + 8)

      new_max = writer->obj_num + 8;

    writer->xref = fz_realloc_array(ctx, writer->xref, new_max, int64_t);

    writer->xref_max = new_max;

  }

  writer->xref[writer->obj_num] = pos;

  return writer->obj_num++;

}

static void

pclm_write_header(fz_context *ctx, fz_band_writer *writer_, fz_colorspace *cs)

{

  pclm_band_writer *writer = (pclm_band_writer *)writer_;

  fz_output *out = writer->super.out;

  int w = writer->super.w;

  int h = writer->super.h;

  int n = writer->super.n;

  int s = writer->super.s;

  int a = writer->super.alpha;

  int xres = writer->super.xres;

  int yres = writer->super.yres;

  int sh = writer->options.strip_height;

  int strips = (h + sh-1)/sh;

  int i;

  size_t len;

  unsigned char *data;

  fz_buffer *buf = NULL;

  if (a != 0)

    fz_throw(ctx, FZ_ERROR_ARGUMENT, "PCLm cannot write alpha channel");

  if (s != 0)

    fz_throw(ctx, FZ_ERROR_ARGUMENT, "PCLm cannot write spot colors");

  if (n != 3 && n != 1)

    fz_throw(ctx, FZ_ERROR_ARGUMENT, "PCLm expected to be Grayscale or RGB");

  fz_free(ctx, writer->stripbuf);

  writer->stripbuf = NULL;

  fz_free(ctx, writer->compbuf);

  writer->compbuf = NULL;

  writer->stripbuf = Memento_label(fz_malloc(ctx, (size_t)w * sh * n), "pclm_stripbuf");

  writer->complen = fz_deflate_bound(ctx, (size_t)w * sh * n);

  writer->compbuf = Memento_label(fz_malloc(ctx, writer->complen), "pclm_compbuf");

  /* Send the file header on the first page */

  if (writer->pages == 0)

    fz_write_string(ctx, out, "%PDF-1.4\n%PCLm-1.0\n");

  if (writer->page_max <= writer->pages)

  {

    int new_max = writer->page_max * 2;

    if (new_max == 0)

      new_max = writer->pages + 8;

    writer->page_obj = fz_realloc_array(ctx, writer->page_obj, new_max, int);

    writer->page_max = new_max;

  }

  writer->page_obj[writer->pages] = writer->obj_num;

  writer->pages++;

  /* Send the Page Object */

  fz_write_printf(ctx, out, "%d 0 obj\n<<\n/Type /Page\n/Parent 2 0 R\n/Resources <<\n/XObject <<\n", new_obj(ctx, writer));

  for (i = 0; i < strips; i++)

    fz_write_printf(ctx, out, "/Image%d %d 0 R\n", i, writer->obj_num + 1 + i);

  fz_write_printf(ctx, out, ">>\n>>\n/MediaBox[ 0 0 %g %g ]\n/Contents [ %d 0 R ]\n>>\nendobj\n",

    w * 72.0f / xres, h * 72.0f / yres, writer->obj_num);

  /* And the Page contents */

  /* We need the length to this, so write to a buffer first */

  fz_var(buf);

  fz_try(ctx)

  {

    buf = fz_new_buffer(ctx, 0);

    fz_append_printf(ctx, buf, "%g 0 0 %g 0 0 cm\n", 72.0f/xres, 72.0f/yres);

    for (i = 0; i < strips; i++)

    {

      int at = h - (i+1)*sh;

      int this_sh = sh;

      if (at < 0)

      {

        this_sh += at;

        at = 0;

      }

      fz_append_printf(ctx, buf, "/P <</MCID 0>> BDC q\n%d 0 0 %d 0 %d cm\n/Image%d Do Q\n",

        w, this_sh, at, i);

    }

    len = fz_buffer_storage(ctx, buf, &data);

    fz_write_printf(ctx, out, "%d 0 obj\n<<\n/Length %zd\n>>\nstream\n", new_obj(ctx, writer), len);

    fz_write_data(ctx, out, data, len);

    fz_drop_buffer(ctx, buf);

    buf = NULL;

    fz_write_string(ctx, out, "\nendstream\nendobj\n");

  }

  fz_catch(ctx)

  {

    fz_drop_buffer(ctx, buf);

    fz_rethrow(ctx);

  }

}

static void

flush_strip(fz_context *ctx, pclm_band_writer *writer, int fill)

{

  unsigned char *data = writer->stripbuf;

  fz_output *out = writer->super.out;

  int w = writer->super.w;

  int n = writer->super.n;

  size_t len = (size_t)w*n*fill;

  /* Buffer is full, compress it and write it. */

  if (writer->options.compress)

  {

    size_t destLen = writer->complen;

    fz_deflate(ctx, writer->compbuf, &destLen, data, len, FZ_DEFLATE_DEFAULT);

    len = destLen;

    data = writer->compbuf;

  }

  fz_write_printf(ctx, out, "%d 0 obj\n<<\n/Width %d\n/ColorSpace /Device%s\n/Height %d\n%s/Subtype /Image\n",

    new_obj(ctx, writer), w, n == 1 ? "Gray" : "RGB", fill, writer->options.compress ? "/Filter /FlateDecode\n" : "");

  fz_write_printf(ctx, out, "/Length %zd\n/Type /XObject\n/BitsPerComponent 8\n>>\nstream\n", len);

  fz_write_data(ctx, out, data, len);

  fz_write_string(ctx, out, "\nendstream\nendobj\n");

}

static void

pclm_write_band(fz_context *ctx, fz_band_writer *writer_, int stride, int band_start, int band_height, const unsigned char *sp)

{

  pclm_band_writer *writer = (pclm_band_writer *)writer_;

  fz_output *out = writer->super.out;

  int w = writer->super.w;

  int h = writer->super.h;

  int n = writer->super.n;

  int sh = writer->options.strip_height;

  int line;

  if (!out)

    return;

  for (line = 0; line < band_height; line++)

  {

    int dstline = (band_start+line) % sh;

    memcpy(writer->stripbuf + (size_t)w*n*dstline,

         sp + (size_t)line * w * n,

         (size_t)w * n);

    if (dstline+1 == sh)

      flush_strip(ctx, writer, dstline+1);

  }

  if (band_start + band_height == h && h % sh != 0)

    flush_strip(ctx, writer, h % sh);

}

static void

pclm_write_trailer(fz_context *ctx, fz_band_writer *writer_)

{

}

static void

pclm_close_band_writer(fz_context *ctx, fz_band_writer *writer_)

{

  pclm_band_writer *writer = (pclm_band_writer *)writer_;

  fz_output *out = writer->super.out;

  int i;

  /* We actually do the trailer writing in the close */

  if (writer->xref_max > 2)

  {

    int64_t t_pos;

    /* Catalog */

    writer->xref[1] = fz_tell_output(ctx, out);

    fz_write_printf(ctx, out, "1 0 obj\n<<\n/Type /Catalog\n/Pages 2 0 R\n>>\nendobj\n");

    /* Page table */

    writer->xref[2] = fz_tell_output(ctx, out);

    fz_write_printf(ctx, out, "2 0 obj\n<<\n/Count %d\n/Kids [ ", writer->pages);

    for (i = 0; i < writer->pages; i++)

      fz_write_printf(ctx, out, "%d 0 R ", writer->page_obj[i]);

    fz_write_string(ctx, out, "]\n/Type /Pages\n>>\nendobj\n");

    /* Xref */

    t_pos = fz_tell_output(ctx, out);

    fz_write_printf(ctx, out, "xref\n0 %d\n0000000000 65535 f \n", writer->obj_num);

    for (i = 1; i < writer->obj_num; i++)

      fz_write_printf(ctx, out, "%010zd 00000 n \n", writer->xref[i]);

    fz_write_printf(ctx, out, "trailer\n<<\n/Size %d\n/Root 1 0 R\n>>\nstartxref\n%ld\n%%%%EOF\n", writer->obj_num, t_pos);

  }

}

static void

pclm_drop_band_writer(fz_context *ctx, fz_band_writer *writer_)

{

  pclm_band_writer *writer = (pclm_band_writer *)writer_;

  fz_free(ctx, writer->stripbuf);

  fz_free(ctx, writer->compbuf);

  fz_free(ctx, writer->page_obj);

  fz_free(ctx, writer->xref);

}

fz_band_writer *fz_new_pclm_band_writer(fz_context *ctx, fz_output *out, const fz_pclm_options *options)

{

  pclm_band_writer *writer = fz_new_band_writer(ctx, pclm_band_writer, out);

  writer->super.header = pclm_write_header;

  writer->super.band = pclm_write_band;

  writer->super.trailer = pclm_write_trailer;

  writer->super.close = pclm_close_band_writer;

  writer->super.drop = pclm_drop_band_writer;

  if (options)

    writer->options = *options;

  else

    memset(&writer->options, 0, sizeof(writer->options));

  if (writer->options.strip_height == 0)

    writer->options.strip_height = 16;

  writer->obj_num = 3; /* 1 reserved for catalog, 2 for pages tree. */

  return &writer->super;

}

void

fz_save_pixmap_as_pclm(fz_context *ctx, fz_pixmap *pixmap, char *filename, int append, const fz_pclm_options *pclm)

{

  fz_output *out = fz_new_output_with_path(ctx, filename, append);

  fz_try(ctx)

  {

    fz_write_pixmap_as_pclm(ctx, out, pixmap, pclm);

    fz_close_output(ctx, out);

  }

  fz_always(ctx)

    fz_drop_output(ctx, out);

  fz_catch(ctx)

    fz_rethrow(ctx);

}

/* High-level document writer interface */

typedef struct

{

  fz_document_writer super;

  fz_draw_options draw;

  fz_pclm_options pclm;

  fz_pixmap *pixmap;

  fz_band_writer *bander;

  fz_output *out;

  int pagenum;

} fz_pclm_writer;

static fz_device *

pclm_begin_page(fz_context *ctx, fz_document_writer *wri_, fz_rect mediabox)

{

  fz_pclm_writer *wri = (fz_pclm_writer*)wri_;

  return fz_new_draw_device_with_options(ctx, &wri->draw, mediabox, &wri->pixmap);

}

static void

pclm_end_page(fz_context *ctx, fz_document_writer *wri_, fz_device *dev)

{

  fz_pclm_writer *wri = (fz_pclm_writer*)wri_;

  fz_pixmap *pix = wri->pixmap;

  fz_try(ctx)

  {

    fz_close_device(ctx, dev);

    fz_write_header(ctx, wri->bander, pix->w, pix->h, pix->n, pix->alpha, pix->xres, pix->yres, wri->pagenum++, pix->colorspace, pix->seps);

    fz_write_band(ctx, wri->bander, pix->stride, pix->h, pix->samples);

  }

  fz_always(ctx)

  {

    fz_drop_device(ctx, dev);

    fz_drop_pixmap(ctx, pix);

    wri->pixmap = NULL;

  }

  fz_catch(ctx)

    fz_rethrow(ctx);

}

static void

pclm_close_writer(fz_context *ctx, fz_document_writer *wri_)

{

  fz_pclm_writer *wri = (fz_pclm_writer*)wri_;

  fz_close_band_writer(ctx, wri->bander);

  fz_close_output(ctx, wri->out);

}

static void

pclm_drop_writer(fz_context *ctx, fz_document_writer *wri_)

{

  fz_pclm_writer *wri = (fz_pclm_writer*)wri_;

  fz_drop_pixmap(ctx, wri->pixmap);

  fz_drop_output(ctx, wri->out);

  fz_drop_band_writer(ctx, wri->bander);

}

fz_document_writer *

fz_new_pclm_writer_with_output(fz_context *ctx, fz_output *out, const char *options)

{

  fz_pclm_writer *wri = NULL;

  fz_var(wri);

  fz_try(ctx)

  {

    wri = fz_new_derived_document_writer(ctx, fz_pclm_writer, pclm_begin_page, pclm_end_page, pclm_close_writer, pclm_drop_writer);

    fz_parse_draw_options(ctx, &wri->draw, options);

    fz_parse_pclm_options(ctx, &wri->pclm, options);

    wri->out = out;

    wri->bander = fz_new_pclm_band_writer(ctx, wri->out, &wri->pclm);

  }

  fz_catch(ctx)

  {

    fz_drop_output(ctx, out);

    fz_free(ctx, wri);

    fz_rethrow(ctx);

  }

  return (fz_document_writer*)wri;

}

fz_document_writer *

fz_new_pclm_writer(fz_context *ctx, const char *path, const char *options)

{

  fz_output *out = fz_new_output_with_path(ctx, path ? path : "out.pclm", 0);

  return fz_new_pclm_writer_with_output(ctx, out, options);

}