// 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 "mupdf/pdf.h"

#include <assert.h>

static int

pdf_make_hash_key(fz_context *ctx, fz_store_hash *hash, void *key_)

{

  pdf_obj *key = (pdf_obj *)key_;

  if (!pdf_is_indirect(ctx, key))

    return 0;

  hash->u.pi.i = pdf_to_num(ctx, key);

  hash->u.pi.ptr = pdf_get_indirect_document(ctx, key);

  return 1;

}

static void *

pdf_keep_key(fz_context *ctx, void *key)

{

  return (void *)pdf_keep_obj(ctx, (pdf_obj *)key);

}

static void

pdf_drop_key(fz_context *ctx, void *key)

{

  pdf_drop_obj(ctx, (pdf_obj *)key);

}

static int

pdf_cmp_key(fz_context *ctx, void *k0, void *k1)

{

  pdf_obj *a = (pdf_obj *)k0;

  pdf_obj *b = (pdf_obj *)k1;

  pdf_document *adoc = pdf_get_bound_document(ctx, a);

  pdf_document *bdoc = pdf_get_bound_document(ctx, b);

  /* Avoid sharing complex objects across documents. */

  if (adoc && bdoc && adoc != bdoc)

    return 1;

  return pdf_objcmp(ctx, a, b);

}

static void

pdf_format_key(fz_context *ctx, char *s, size_t n, void *key_)

{

  pdf_obj *key = (pdf_obj *)key_;

  if (pdf_is_indirect(ctx, key))

    fz_snprintf(s, n, "(%d 0 R)", pdf_to_num(ctx, key));

  else

  {

    size_t t;

    char *p = pdf_sprint_obj(ctx, s, n, &t, key, 1, 0);

    if (p != s) {

      fz_strlcpy(s, p, n);

      fz_free(ctx, p);

    }

  }

}

static const fz_store_type pdf_obj_store_type =

{

  "pdf_obj",

  pdf_make_hash_key,

  pdf_keep_key,

  pdf_drop_key,

  pdf_cmp_key,

  pdf_format_key,

  NULL

};

void

pdf_store_item(fz_context *ctx, pdf_obj *key, void *val, size_t itemsize)

{

  void *existing;

  assert(pdf_is_name(ctx, key) || pdf_is_array(ctx, key) || pdf_is_dict(ctx, key) || pdf_is_indirect(ctx, key));

  existing = fz_store_item(ctx, key, val, itemsize, &pdf_obj_store_type);

  if (existing)

    fz_warn(ctx, "unexpectedly replacing entry in PDF store");

}

void *

pdf_find_item(fz_context *ctx, fz_store_drop_fn *drop, pdf_obj *key)

{

  return fz_find_item(ctx, drop, key, &pdf_obj_store_type);

}

void

pdf_remove_item(fz_context *ctx, fz_store_drop_fn *drop, pdf_obj *key)

{

  fz_remove_item(ctx, drop, key, &pdf_obj_store_type);

}

static int

pdf_filter_store(fz_context *ctx, void *doc_, void *key)

{

  pdf_document *doc = (pdf_document *)doc_;

  pdf_obj *obj = (pdf_obj *)key;

  pdf_document *key_doc = pdf_get_bound_document(ctx, obj);

  return (doc == key_doc);

}

void

pdf_empty_store(fz_context *ctx, pdf_document *doc)

{

  fz_filter_store(ctx, pdf_filter_store, doc, &pdf_obj_store_type);

  fz_drop_drawn_tiles_for_document(ctx, (fz_document *)doc);

}

static int

pdf_filter_locals(fz_context *ctx, void *doc_, void *key)

{

  pdf_document *doc = (pdf_document *)doc_;

  pdf_obj *obj = (pdf_obj *)key;

  pdf_document *key_doc = pdf_get_bound_document(ctx, obj);

  return (doc == key_doc && pdf_is_local_object(ctx, doc, obj));

}

void pdf_purge_locals_from_store(fz_context *ctx, pdf_document *doc)

{

  fz_filter_store(ctx, pdf_filter_locals, doc, &pdf_obj_store_type);

}

struct doc_num_info {

  pdf_document *doc;

  int num;

};

static int

pdf_filter_object_number(fz_context *ctx, void *ref_, void *key_)

{

  struct doc_num_info *ref = ref_;

  pdf_obj *key_obj = (pdf_obj *)key_;

  pdf_document *key_doc = pdf_get_bound_document(ctx, key_obj);

  return (ref->doc == key_doc && ref->num == pdf_to_num(ctx, key_obj));

}

void pdf_purge_object_from_store(fz_context *ctx, pdf_document *doc, int num)

{

  struct doc_num_info ref = { doc, num };

  fz_filter_store(ctx, pdf_filter_object_number, &ref, &pdf_obj_store_type);

}