# Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
# file Copyright.txt or https://cmake.org/licensing for details.

#[=======================================================================[.rst:
FindGnuTLS
----------

Find the GNU Transport Layer Security library (gnutls)

IMPORTED Targets
^^^^^^^^^^^^^^^^

.. versionadded:: 3.16

This module defines :prop_tgt:`IMPORTED` target ``GnuTLS::GnuTLS``, if
gnutls has been found.

Result Variables
^^^^^^^^^^^^^^^^

``GNUTLS_FOUND``
  System has gnutls
``GNUTLS_INCLUDE_DIR``
  The gnutls include directory
``GNUTLS_LIBRARIES``
  The libraries needed to use gnutls
``GNUTLS_DEFINITIONS``
  Compiler switches required for using gnutls
``GNUTLS_VERSION``
  version of gnutls.
#]=======================================================================]

# Note that this doesn't try to find the gnutls-extra package.


if (GNUTLS_INCLUDE_DIR AND GNUTLS_LIBRARY)
  # in cache already
  set(gnutls_FIND_QUIETLY TRUE)
endif ()

if (NOT WIN32)
  # try using pkg-config to get the directories and then use these values
  # in the find_path() and find_library() calls
  # also fills in GNUTLS_DEFINITIONS, although that isn't normally useful
  find_package(PkgConfig QUIET)
  PKG_CHECK_MODULES(PC_GNUTLS QUIET gnutls)
  set(GNUTLS_DEFINITIONS ${PC_GNUTLS_CFLAGS_OTHER})
  set(GNUTLS_VERSION ${PC_GNUTLS_VERSION})
  # keep for backward compatibility
  set(GNUTLS_VERSION_STRING ${PC_GNUTLS_VERSION})
endif ()

find_path(GNUTLS_INCLUDE_DIR gnutls/gnutls.h
  HINTS
    ${PC_GNUTLS_INCLUDEDIR}
    ${PC_GNUTLS_INCLUDE_DIRS}
  )

find_library(GNUTLS_LIBRARY NAMES gnutls libgnutls
  HINTS
    ${PC_GNUTLS_LIBDIR}
    ${PC_GNUTLS_LIBRARY_DIRS}
  )

mark_as_advanced(GNUTLS_INCLUDE_DIR GNUTLS_LIBRARY)

include(${CMAKE_CURRENT_LIST_DIR}/FindPackageHandleStandardArgs.cmake)
FIND_PACKAGE_HANDLE_STANDARD_ARGS(GnuTLS
                                  REQUIRED_VARS GNUTLS_LIBRARY GNUTLS_INCLUDE_DIR
                                  VERSION_VAR GNUTLS_VERSION_STRING)

if(GNUTLS_FOUND)
  set(GNUTLS_LIBRARIES    ${GNUTLS_LIBRARY})
  set(GNUTLS_INCLUDE_DIRS ${GNUTLS_INCLUDE_DIR})

  if(NOT TARGET GnuTLS::GnuTLS)
    add_library(GnuTLS::GnuTLS UNKNOWN IMPORTED)
    set_target_properties(GnuTLS::GnuTLS PROPERTIES
      INTERFACE_INCLUDE_DIRECTORIES "${GNUTLS_INCLUDE_DIRS}"
      INTERFACE_COMPILE_DEFINITIONS "${GNUTLS_DEFINITIONS}"
      IMPORTED_LINK_INTERFACE_LANGUAGES "C"
      IMPORTED_LOCATION "${GNUTLS_LIBRARIES}")
  endif()
endif()
