// Copyright (C) 2004-2023 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 <math.h>

fz_link *

fz_new_link_of_size(fz_context *ctx, int size, fz_rect rect, const char *uri)

{

  fz_link *link = Memento_label(fz_calloc(ctx, 1, size), "fz_link");

  link->refs = 1;

  link->rect = rect;

  fz_try(ctx)

    link->uri = fz_strdup(ctx, uri);

  fz_catch(ctx)

  {

    fz_drop_link(ctx, link);

    fz_rethrow(ctx);

  }

  return link;

}

fz_link *

fz_keep_link(fz_context *ctx, fz_link *link)

{

  return fz_keep_imp(ctx, link, &link->refs);

}

void

fz_drop_link(fz_context *ctx, fz_link *link)

{

  while (fz_drop_imp(ctx, link, &link->refs))

  {

    fz_link *next = link->next;

    if (link->drop)

      link->drop(ctx, link);

    fz_free(ctx, link->uri);

    fz_free(ctx, link);

    link = next;

  }

}

int

fz_is_external_link(fz_context *ctx, const char *uri)

{

  const char *mark;

  /* Basically, this function returns true, if the URI starts with

   * a valid 'scheme' followed by ':'. */

   if (!uri)

     return 0;

  /* All schemes must start with a letter; exit if we don't. */

  if ((*uri < 'a' || *uri > 'z') && (*uri < 'A' || *uri > 'Z'))

    return 0;

  uri++;

  mark = uri;

  /* Subsequent characters can be letters, digits, +, -, or . */

  while ((*uri >= 'a' && *uri <= 'z') ||

    (*uri >= 'A' && *uri <= 'Z') ||

    (*uri >= '0' && *uri <= '9') ||

    (*uri == '+') ||

    (*uri == '-') ||

    (*uri == '.'))

    ++uri;

  return uri[0] == ':' && (uri - mark) > 1;

}

fz_link_dest fz_make_link_dest_none(void)

{

  fz_link_dest dest = { { -1, -1 }, FZ_LINK_DEST_XYZ, NAN, NAN, NAN, NAN, NAN };

  return dest;

}

fz_link_dest fz_make_link_dest_xyz(int chapter, int page, float x, float y, float z)

{

  fz_link_dest dest = { { chapter, page }, FZ_LINK_DEST_XYZ, x, y, NAN, NAN, z };

  return dest;

}