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

# XXX: Copied from CMake, but includes vtkDetectLibraryType.
# See https://gitlab.kitware.com/cmake/cmake/issues/18564

#[=======================================================================[.rst:
FindEXPAT
---------

Find the native Expat headers and library.

Imported Targets
^^^^^^^^^^^^^^^^

This module defines the following :prop_tgt:`IMPORTED` targets:

``EXPAT::EXPAT``
  The Expat ``expat`` library, if found.

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

This module will set the following variables in your project:

``EXPAT_INCLUDE_DIRS``
  where to find expat.h, etc.
``EXPAT_LIBRARIES``
  the libraries to link against to use Expat.
``EXPAT_FOUND``
  true if the Expat headers and libraries were found.

#]=======================================================================]

find_package(PkgConfig QUIET)

pkg_check_modules(PC_EXPAT QUIET expat)

# Look for the header file.
find_path(EXPAT_INCLUDE_DIR NAMES expat.h HINTS ${PC_EXPAT_INCLUDE_DIRS})

# Look for the library.
find_library(EXPAT_LIBRARY NAMES expat libexpat HINTS ${PC_EXPAT_LIBRARY_DIRS})

if (EXPAT_INCLUDE_DIR AND EXISTS "${EXPAT_INCLUDE_DIR}/expat.h")
    file(STRINGS "${EXPAT_INCLUDE_DIR}/expat.h" expat_version_str
         REGEX "^#[\t ]*define[\t ]+XML_(MAJOR|MINOR|MICRO)_VERSION[\t ]+[0-9]+$")

    unset(EXPAT_VERSION_STRING)
    foreach(VPART MAJOR MINOR MICRO)
        foreach(VLINE ${expat_version_str})
            if(VLINE MATCHES "^#[\t ]*define[\t ]+XML_${VPART}_VERSION[\t ]+([0-9]+)$")
                set(EXPAT_VERSION_PART "${CMAKE_MATCH_1}")
                if(EXPAT_VERSION_STRING)
                    string(APPEND EXPAT_VERSION_STRING ".${EXPAT_VERSION_PART}")
                else()
                    set(EXPAT_VERSION_STRING "${EXPAT_VERSION_PART}")
                endif()
            endif()
        endforeach()
    endforeach()
endif ()

include(FindPackageHandleStandardArgs)
FIND_PACKAGE_HANDLE_STANDARD_ARGS(EXPAT
                                  REQUIRED_VARS EXPAT_LIBRARY EXPAT_INCLUDE_DIR
                                  VERSION_VAR EXPAT_VERSION_STRING)

# Copy the results to the output variables and target.
if(EXPAT_FOUND)
  set(EXPAT_LIBRARIES ${EXPAT_LIBRARY})
  set(EXPAT_INCLUDE_DIRS ${EXPAT_INCLUDE_DIR})

  if(NOT TARGET EXPAT::EXPAT)
    include(vtkDetectLibraryType)
    vtk_detect_library_type(expat_library_type
      PATH "${EXPAT_LIBRARY}")
    add_library(EXPAT::EXPAT "${expat_library_type}" IMPORTED)
    unset(expat_library_type)
    set_target_properties(EXPAT::EXPAT PROPERTIES
      IMPORTED_LINK_INTERFACE_LANGUAGES "C"
      IMPORTED_LOCATION "${EXPAT_LIBRARY}"
      IMPORTED_IMPLIB "${EXPAT_LIBRARY}"
      INTERFACE_INCLUDE_DIRECTORIES "${EXPAT_INCLUDE_DIRS}")
  endif()
endif()

mark_as_advanced(EXPAT_INCLUDE_DIR EXPAT_LIBRARY)