/*

 * Compression functions

 *

 * Copyright (C) 2018-2024, Joachim Metz <joachim.metz@gmail.com>

 *

 * Refer to AUTHORS for acknowledgements.

 *

 * This program is free software: you can redistribute it and/or modify

 * it under the terms of the GNU Lesser General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 *

 * This program 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 General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with this program.  If not, see <https://www.gnu.org/licenses/>.

 */

#include <common.h>

#include <memory.h>

#include <types.h>

#if defined( HAVE_STDLIB_H ) || defined( WINAPI )

#include <stdlib.h>

#endif

#if defined( HAVE_ZLIB ) || defined( ZLIB_DLL )

#include <zlib.h>

#endif

#include "libfsapfs_compression.h"

#include "libfsapfs_definitions.h"

#include "libfsapfs_deflate.h"

#include "libfsapfs_libcerror.h"

#include "libfsapfs_libcnotify.h"

#include "libfsapfs_libfmos.h"

/* Decompresses data using the compression method

 * Returns 1 on success, 0 on failure or -1 on error

 */

int libfsapfs_decompress_data(

     const uint8_t *compressed_data,

     size_t compressed_data_size,

     int compression_method,

     uint8_t *uncompressed_data,

     size_t *uncompressed_data_size,

     libcerror_error_t **error )

{

  static char *function              = "libfsapfs_decompress_data";

  int result                         = 0;

#if ( defined( HAVE_ZLIB ) && defined( HAVE_ZLIB_UNCOMPRESS ) ) || defined( ZLIB_DLL )

  uLongf zlib_uncompressed_data_size = 0;

#endif

  if( compressed_data == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid compressed data buffer.",

     function );

    return( -1 );

  }

  if( uncompressed_data == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid uncompressed data buffer.",

     function );

    return( -1 );

  }

  if( uncompressed_data == compressed_data )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid compressed data buffer equals uncompressed data buffer.",

     function );

    return( -1 );

  }

  if( uncompressed_data_size == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid uncompressed data size.",

     function );

    return( -1 );

  }

  if( compression_method == LIBFSAPFS_COMPRESSION_METHOD_DEFLATE )

  {

    if( ( compressed_data_size >= 1 )

     && ( compressed_data[ 0 ] == 0xff ) )

    {

      if( compressed_data_size > (size_t) SSIZE_MAX )

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

         LIBCERROR_ARGUMENT_ERROR_VALUE_EXCEEDS_MAXIMUM,

         "%s: invalid compressed data size value exceeds maximum.",

         function );

        return( -1 );

      }

      if( *uncompressed_data_size > (size_t) SSIZE_MAX )

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

         LIBCERROR_ARGUMENT_ERROR_VALUE_EXCEEDS_MAXIMUM,

         "%s: invalid uncompressed data size value exceeds maximum.",

         function );

        return( -1 );

      }

      if( ( compressed_data_size - 1 ) > *uncompressed_data_size )

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_RUNTIME,

         LIBCERROR_RUNTIME_ERROR_VALUE_OUT_OF_BOUNDS,

         "%s: compressed data size value exceeds uncompressed data size.",

         function );

        return( -1 );

      }

      *uncompressed_data_size = compressed_data_size - 1;

      if( memory_copy(

           uncompressed_data,

           &( compressed_data[ 1 ] ),

           *uncompressed_data_size ) == NULL )

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_MEMORY,

         LIBCERROR_MEMORY_ERROR_COPY_FAILED,

         "%s: unable to compressed to uncompressed data.",

         function );

        return( -1 );

      }

      result = 1;

    }

    else

    {

#if ( defined( HAVE_ZLIB ) && defined( HAVE_ZLIB_UNCOMPRESS ) ) || defined( ZLIB_DLL )

      if( compressed_data_size > (size_t) ULONG_MAX )

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

         LIBCERROR_ARGUMENT_ERROR_VALUE_EXCEEDS_MAXIMUM,

         "%s: invalid compressed data size value exceeds maximum.",

         function );

        return( -1 );

      }

      if( *uncompressed_data_size > (size_t) ULONG_MAX )

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

         LIBCERROR_ARGUMENT_ERROR_VALUE_EXCEEDS_MAXIMUM,

         "%s: invalid uncompressed data size value exceeds maximum.",

         function );

        return( -1 );

      }

      zlib_uncompressed_data_size = (uLongf) *uncompressed_data_size;

      result = uncompress(

          (Bytef *) uncompressed_data,

          &zlib_uncompressed_data_size,

          (Bytef *) compressed_data,

          (uLong) compressed_data_size );

      if( result == Z_OK )

      {

        *uncompressed_data_size = (size_t) zlib_uncompressed_data_size;

        result = 1;

      }

      else if( result == Z_DATA_ERROR )

      {

#if defined( HAVE_DEBUG_OUTPUT )

        if( libcnotify_verbose != 0 )

        {

          libcnotify_printf(

           "%s: unable to read compressed data: data error.\n",

           function );

        }

#endif

        *uncompressed_data_size = 0;

        result = -1;

      }

      else if( result == Z_BUF_ERROR )

      {

#if defined( HAVE_DEBUG_OUTPUT )

        if( libcnotify_verbose != 0 )

        {

          libcnotify_printf(

          "%s: unable to read compressed data: target buffer too small.\n",

           function );

        }

#endif

        /* Estimate that a factor 2 enlargement should suffice

         */

        *uncompressed_data_size *= 2;

        result = 0;

      }

      else if( result == Z_MEM_ERROR )

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_MEMORY,

         LIBCERROR_MEMORY_ERROR_INSUFFICIENT,

         "%s: unable to read compressed data: insufficient memory.",

         function );

        *uncompressed_data_size = 0;

        result = -1;

      }

      else

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_COMPRESSION,

         LIBCERROR_COMPRESSION_ERROR_DECOMPRESS_FAILED,

         "%s: zlib returned undefined error: %d.",

         function,

         result );

        *uncompressed_data_size = 0;

        result = -1;

      }

#else

      result = libfsapfs_deflate_decompress_zlib(

                compressed_data,

                compressed_data_size,

                uncompressed_data,

                uncompressed_data_size,

                error );

      if( result != 1 )

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_ENCRYPTION,

         LIBCERROR_ENCRYPTION_ERROR_GENERIC,

         "%s: unable to decompress DEFLATE compressed data.",

         function );

        return( -1 );

      }

#endif /* ( defined( HAVE_ZLIB ) && defined( HAVE_ZLIB_UNCOMPRESS ) ) || defined( ZLIB_DLL ) */

    }

  }

#ifdef TODO

/* TODO need sample data */

  else if( compression_method == LIBFSAPFS_COMPRESSION_METHOD_LZFSE )

  {

    result = libfmos_lzfse_decompress(

              compressed_data,

              compressed_data_size,

              uncompressed_data,

              uncompressed_data_size,

              error );

    if( result != 1 )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_ENCRYPTION,

       LIBCERROR_ENCRYPTION_ERROR_GENERIC,

       "%s: unable to decompress LZFSE compressed data.",

       function );

      return( -1 );

    }

  }

#endif /* TODO */

  else if( compression_method == LIBFSAPFS_COMPRESSION_METHOD_LZVN )

  {

    if( ( compressed_data_size >= 1 )

     && ( compressed_data[ 0 ] == 0x06 ) )

    {

      if( compressed_data_size > (size_t) SSIZE_MAX )

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

         LIBCERROR_ARGUMENT_ERROR_VALUE_EXCEEDS_MAXIMUM,

         "%s: invalid compressed data size value exceeds maximum.",

         function );

        return( -1 );

      }

      if( *uncompressed_data_size > (size_t) SSIZE_MAX )

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

         LIBCERROR_ARGUMENT_ERROR_VALUE_EXCEEDS_MAXIMUM,

         "%s: invalid uncompressed data size value exceeds maximum.",

         function );

        return( -1 );

      }

      if( ( compressed_data_size - 1 ) > *uncompressed_data_size )

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_RUNTIME,

         LIBCERROR_RUNTIME_ERROR_VALUE_OUT_OF_BOUNDS,

         "%s: compressed data size value exceeds uncompressed data size.",

         function );

        return( -1 );

      }

      *uncompressed_data_size = compressed_data_size - 1;

      if( memory_copy(

           uncompressed_data,

           &( compressed_data[ 1 ] ),

           *uncompressed_data_size ) == NULL )

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_MEMORY,

         LIBCERROR_MEMORY_ERROR_COPY_FAILED,

         "%s: unable to compressed to uncompressed data.",

         function );

        return( -1 );

      }

      result = 1;

    }

    else

    {

      result = libfmos_lzvn_decompress(

                compressed_data,

                compressed_data_size,

                uncompressed_data,

                uncompressed_data_size,

                error );

      if( result != 1 )

      {

        libcerror_error_set(

         error,

         LIBCERROR_ERROR_DOMAIN_ENCRYPTION,

         LIBCERROR_ENCRYPTION_ERROR_GENERIC,

         "%s: unable to decompress LZVN compressed data.",

         function );

        return( -1 );

      }

    }

  }

  else

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_UNSUPPORTED_VALUE,

     "%s: unsupported compression method.",

     function );

    return( -1 );

  }

  return( result );

}