###
#
# @copyright (c) 2009-2014 The University of Tennessee and The University
#                          of Tennessee Research Foundation.
#                          All rights reserved.
# @copyright (c) 2012-2014 Inria. All rights reserved.
# @copyright (c) 2012-2014 Bordeaux INP, CNRS (LaBRI UMR 5800), Inria, Univ. Bordeaux. All rights reserved.
#
###
#
# - Find HWLOC include dirs and libraries
# Use this module by invoking find_package with the form:
#  find_package(HWLOC
#               [REQUIRED]) # Fail with error if hwloc is not found
#
# This module finds headers and hwloc library.
# Results are reported in variables:
#  HWLOC_FOUND           - True if headers and requested libraries were found
#  HWLOC_INCLUDE_DIRS    - hwloc include directories
#  HWLOC_LIBRARY_DIRS    - Link directories for hwloc libraries
#  HWLOC_LIBRARIES       - hwloc component libraries to be linked
#
# The user can give specific paths where to find the libraries adding cmake
# options at configure (ex: cmake path/to/project -DHWLOC_DIR=path/to/hwloc):
#  HWLOC_DIR             - Where to find the base directory of hwloc
#  HWLOC_INCDIR          - Where to find the header files
#  HWLOC_LIBDIR          - Where to find the library files
# The module can also look for the following environment variables if paths
# are not given as cmake variable: HWLOC_DIR, HWLOC_INCDIR, HWLOC_LIBDIR

#=============================================================================
# Copyright 2012-2013 Inria
# Copyright 2012-2013 Emmanuel Agullo
# Copyright 2012-2013 Mathieu Faverge
# Copyright 2012      Cedric Castagnede
# Copyright 2013      Florent Pruvost
#
# Distributed under the OSI-approved BSD License (the "License");
# see accompanying file MORSE-Copyright.txt for details.
#
# This software is distributed WITHOUT ANY WARRANTY; without even the
# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
# See the License for more information.
#=============================================================================
# (To distribute this file outside of Morse, substitute the full
#  License text for the above reference.)

include(CheckStructHasMember)
include(CheckCSourceCompiles)

if (NOT HWLOC_FOUND)
  set(HWLOC_DIR "" CACHE PATH "Installation directory of HWLOC library")
  if (NOT HWLOC_FIND_QUIETLY)
    message(STATUS "A cache variable, namely HWLOC_DIR, has been set to specify the install directory of HWLOC")
  endif()
endif()

set(ENV_HWLOC_DIR "$ENV{HWLOC_DIR}")
set(ENV_HWLOC_INCDIR "$ENV{HWLOC_INCDIR}")
set(ENV_HWLOC_LIBDIR "$ENV{HWLOC_LIBDIR}")
set(HWLOC_GIVEN_BY_USER "FALSE")
if ( HWLOC_DIR OR ( HWLOC_INCDIR AND HWLOC_LIBDIR) OR ENV_HWLOC_DIR OR (ENV_HWLOC_INCDIR AND ENV_HWLOC_LIBDIR) )
  set(HWLOC_GIVEN_BY_USER "TRUE")
endif()

# Optionally use pkg-config to detect include/library dirs (if pkg-config is available)
# -------------------------------------------------------------------------------------
find_package(PkgConfig QUIET)
if( PKG_CONFIG_EXECUTABLE AND NOT HWLOC_GIVEN_BY_USER )

  pkg_search_module(HWLOC hwloc)
  if (NOT HWLOC_FIND_QUIETLY)
    if (HWLOC_FOUND AND HWLOC_LIBRARIES)
      message(STATUS "Looking for HWLOC - found using PkgConfig")
      #if(NOT HWLOC_INCLUDE_DIRS)
      #    message("${Magenta}HWLOC_INCLUDE_DIRS is empty using PkgConfig."
      #        "Perhaps the path to hwloc headers is already present in your"
      #        "C(PLUS)_INCLUDE_PATH environment variable.${ColourReset}")
      #endif()
    else()
      message(STATUS "${Magenta}Looking for HWLOC - not found using PkgConfig."
	"\n   Perhaps you should add the directory containing hwloc.pc to"
	"\n   the PKG_CONFIG_PATH environment variable.${ColourReset}")
    endif()
  endif()

endif( PKG_CONFIG_EXECUTABLE AND NOT HWLOC_GIVEN_BY_USER )

if( (NOT PKG_CONFIG_EXECUTABLE) OR (PKG_CONFIG_EXECUTABLE AND NOT HWLOC_FOUND) OR (HWLOC_GIVEN_BY_USER) )

  if (NOT HWLOC_FIND_QUIETLY)
    message(STATUS "Looking for HWLOC - PkgConfig not used")
  endif()

  # Looking for include
  # -------------------

  # Add system include paths to search include
  # ------------------------------------------
  unset(_inc_env)
  if(ENV_HWLOC_INCDIR)
    list(APPEND _inc_env "${ENV_HWLOC_INCDIR}")
  elseif(ENV_HWLOC_DIR)
    list(APPEND _inc_env "${ENV_HWLOC_DIR}")
    list(APPEND _inc_env "${ENV_HWLOC_DIR}/include")
    list(APPEND _inc_env "${ENV_HWLOC_DIR}/include/hwloc")
  else()
    if(WIN32)
      string(REPLACE ":" ";" _inc_env "$ENV{INCLUDE}")
    else()
      string(REPLACE ":" ";" _path_env "$ENV{INCLUDE}")
      list(APPEND _inc_env "${_path_env}")
      string(REPLACE ":" ";" _path_env "$ENV{C_INCLUDE_PATH}")
      list(APPEND _inc_env "${_path_env}")
      string(REPLACE ":" ";" _path_env "$ENV{CPATH}")
      list(APPEND _inc_env "${_path_env}")
      string(REPLACE ":" ";" _path_env "$ENV{INCLUDE_PATH}")
      list(APPEND _inc_env "${_path_env}")
    endif()
  endif()
  list(APPEND _inc_env "${CMAKE_PLATFORM_IMPLICIT_INCLUDE_DIRECTORIES}")
  list(APPEND _inc_env "${CMAKE_C_IMPLICIT_INCLUDE_DIRECTORIES}")
  list(REMOVE_DUPLICATES _inc_env)

  # set paths where to look for
  set(PATH_TO_LOOK_FOR "${_inc_env}")

  # Try to find the hwloc header in the given paths
  # -------------------------------------------------
  # call cmake macro to find the header path
  if(HWLOC_INCDIR)
    set(HWLOC_hwloc.h_DIRS "HWLOC_hwloc.h_DIRS-NOTFOUND")
    find_path(HWLOC_hwloc.h_DIRS
      NAMES hwloc.h
      HINTS ${HWLOC_INCDIR})
  else()
    if(HWLOC_DIR)
      set(HWLOC_hwloc.h_DIRS "HWLOC_hwloc.h_DIRS-NOTFOUND")
      find_path(HWLOC_hwloc.h_DIRS
	NAMES hwloc.h
	HINTS ${HWLOC_DIR}
	PATH_SUFFIXES "include" "include/hwloc")
    else()
      set(HWLOC_hwloc.h_DIRS "HWLOC_hwloc.h_DIRS-NOTFOUND")
      find_path(HWLOC_hwloc.h_DIRS
	NAMES hwloc.h
	HINTS ${PATH_TO_LOOK_FOR}
	PATH_SUFFIXES "hwloc")
    endif()
  endif()
  mark_as_advanced(HWLOC_hwloc.h_DIRS)

  # Add path to cmake variable
  # ------------------------------------
  if (HWLOC_hwloc.h_DIRS)
    set(HWLOC_INCLUDE_DIRS "${HWLOC_hwloc.h_DIRS}")
  else ()
    set(HWLOC_INCLUDE_DIRS "HWLOC_INCLUDE_DIRS-NOTFOUND")
    if(NOT HWLOC_FIND_QUIETLY)
      message(STATUS "Looking for hwloc -- hwloc.h not found")
    endif()
  endif ()

  if (HWLOC_INCLUDE_DIRS)
    list(REMOVE_DUPLICATES HWLOC_INCLUDE_DIRS)
  endif ()


  # Looking for lib
  # ---------------

  # Add system library paths to search lib
  # --------------------------------------
  unset(_lib_env)
  if(ENV_HWLOC_LIBDIR)
    list(APPEND _lib_env "${ENV_HWLOC_LIBDIR}")
  elseif(ENV_HWLOC_DIR)
    list(APPEND _lib_env "${ENV_HWLOC_DIR}")
    list(APPEND _lib_env "${ENV_HWLOC_DIR}/lib")
  else()
    if(WIN32)
      string(REPLACE ":" ";" _lib_env "$ENV{LIB}")
    else()
      if(APPLE)
	string(REPLACE ":" ";" _lib_env "$ENV{DYLD_LIBRARY_PATH}")
      else()
	string(REPLACE ":" ";" _lib_env "$ENV{LD_LIBRARY_PATH}")
      endif()
      list(APPEND _lib_env "${CMAKE_PLATFORM_IMPLICIT_LINK_DIRECTORIES}")
      list(APPEND _lib_env "${CMAKE_C_IMPLICIT_LINK_DIRECTORIES}")
    endif()
  endif()
  list(REMOVE_DUPLICATES _lib_env)

  # set paths where to look for
  set(PATH_TO_LOOK_FOR "${_lib_env}")

  # Try to find the hwloc lib in the given paths
  # ----------------------------------------------

  # call cmake macro to find the lib path
  if(HWLOC_LIBDIR)
    set(HWLOC_hwloc_LIBRARY "HWLOC_hwloc_LIBRARY-NOTFOUND")
    find_library(HWLOC_hwloc_LIBRARY
      NAMES hwloc
      HINTS ${HWLOC_LIBDIR})
  else()
    if(HWLOC_DIR)
      set(HWLOC_hwloc_LIBRARY "HWLOC_hwloc_LIBRARY-NOTFOUND")
      find_library(HWLOC_hwloc_LIBRARY
	NAMES hwloc
	HINTS ${HWLOC_DIR}
	PATH_SUFFIXES lib lib32 lib64)
    else()
      set(HWLOC_hwloc_LIBRARY "HWLOC_hwloc_LIBRARY-NOTFOUND")
      find_library(HWLOC_hwloc_LIBRARY
	NAMES hwloc
	HINTS ${PATH_TO_LOOK_FOR})
    endif()
  endif()
  mark_as_advanced(HWLOC_hwloc_LIBRARY)

  # If found, add path to cmake variable
  # ------------------------------------
  if (HWLOC_hwloc_LIBRARY)
    get_filename_component(hwloc_lib_path ${HWLOC_hwloc_LIBRARY} PATH)
    # set cmake variables (respects naming convention)
    set(HWLOC_LIBRARIES    "${HWLOC_hwloc_LIBRARY}")
    set(HWLOC_LIBRARY_DIRS "${hwloc_lib_path}")
  else ()
    set(HWLOC_LIBRARIES    "HWLOC_LIBRARIES-NOTFOUND")
    set(HWLOC_LIBRARY_DIRS "HWLOC_LIBRARY_DIRS-NOTFOUND")
    if(NOT HWLOC_FIND_QUIETLY)
      message(STATUS "Looking for hwloc -- lib hwloc not found")
    endif()
  endif ()

  if (HWLOC_LIBRARY_DIRS)
    list(REMOVE_DUPLICATES HWLOC_LIBRARY_DIRS)
  endif ()

  # check a function to validate the find
  if(HWLOC_LIBRARIES)

    set(REQUIRED_INCDIRS)
    set(REQUIRED_LIBDIRS)
    set(REQUIRED_LIBS)

    # HWLOC
    if (HWLOC_INCLUDE_DIRS)
      set(REQUIRED_INCDIRS "${HWLOC_INCLUDE_DIRS}")
    endif()
    if (HWLOC_LIBRARY_DIRS)
      set(REQUIRED_LIBDIRS "${HWLOC_LIBRARY_DIRS}")
    endif()
    set(REQUIRED_LIBS "${HWLOC_LIBRARIES}")

    # set required libraries for link
    set(CMAKE_REQUIRED_INCLUDES "${REQUIRED_INCDIRS}")
    set(CMAKE_REQUIRED_LIBRARIES)
    foreach(lib_dir ${REQUIRED_LIBDIRS})
      list(APPEND CMAKE_REQUIRED_LIBRARIES "-L${lib_dir}")
    endforeach()
    list(APPEND CMAKE_REQUIRED_LIBRARIES "${REQUIRED_LIBS}")
    string(REGEX REPLACE "^ -" "-" CMAKE_REQUIRED_LIBRARIES "${CMAKE_REQUIRED_LIBRARIES}")

    # test link
    unset(HWLOC_WORKS CACHE)
    include(CheckFunctionExists)
    check_function_exists(hwloc_topology_init HWLOC_WORKS)
    mark_as_advanced(HWLOC_WORKS)

    if(NOT HWLOC_WORKS)
      if(NOT HWLOC_FIND_QUIETLY)
	message(STATUS "Looking for hwloc : test of hwloc_topology_init with hwloc library fails")
	message(STATUS "CMAKE_REQUIRED_LIBRARIES: ${CMAKE_REQUIRED_LIBRARIES}")
	message(STATUS "CMAKE_REQUIRED_INCLUDES: ${CMAKE_REQUIRED_INCLUDES}")
	message(STATUS "Check in CMakeFiles/CMakeError.log to figure out why it fails")
      endif()
    endif()
    set(CMAKE_REQUIRED_INCLUDES)
    set(CMAKE_REQUIRED_FLAGS)
    set(CMAKE_REQUIRED_LIBRARIES)
  endif(HWLOC_LIBRARIES)

endif( (NOT PKG_CONFIG_EXECUTABLE) OR (PKG_CONFIG_EXECUTABLE AND NOT HWLOC_FOUND) OR (HWLOC_GIVEN_BY_USER) )

if (HWLOC_LIBRARIES)
  if (HWLOC_LIBRARY_DIRS)
    list(GET HWLOC_LIBRARY_DIRS 0 first_lib_path)
  else()
    list(GET HWLOC_LIBRARIES 0 first_lib)
    get_filename_component(first_lib_path "${first_lib}" PATH)
  endif()
  if (${first_lib_path} MATCHES "/lib(32|64)?$")
    string(REGEX REPLACE "/lib(32|64)?$" "" not_cached_dir "${first_lib_path}")
    set(HWLOC_DIR_FOUND "${not_cached_dir}" CACHE PATH "Installation directory of HWLOC library" FORCE)
  else()
    set(HWLOC_DIR_FOUND "${first_lib_path}" CACHE PATH "Installation directory of HWLOC library" FORCE)
  endif()
endif()
mark_as_advanced(HWLOC_DIR)
mark_as_advanced(HWLOC_DIR_FOUND)

# check that HWLOC has been found
# -------------------------------
include(FindPackageHandleStandardArgs)
if (PKG_CONFIG_EXECUTABLE AND HWLOC_FOUND)
  find_package_handle_standard_args(HWLOC DEFAULT_MSG HWLOC_LIBRARIES)
else()
  find_package_handle_standard_args(HWLOC DEFAULT_MSG HWLOC_LIBRARIES HWLOC_WORKS)
endif()

if (HWLOC_FOUND)
  set(HWLOC_SAVE_CMAKE_REQUIRED_INCLUDES ${CMAKE_REQUIRED_INCLUDES})
  list(APPEND CMAKE_REQUIRED_INCLUDES ${HWLOC_INCLUDE_DIRS})

  # test headers to guess the version
  check_struct_has_member( "struct hwloc_obj" parent hwloc.h HAVE_HWLOC_PARENT_MEMBER )
  check_struct_has_member( "struct hwloc_cache_attr_s" size hwloc.h HAVE_HWLOC_CACHE_ATTR )
  check_c_source_compiles( "#include <hwloc.h>
	    int main(void) { hwloc_obj_t o; o->type = HWLOC_OBJ_PU; return 0;}" HAVE_HWLOC_OBJ_PU)
  include(CheckLibraryExists)
  check_library_exists(${HWLOC_LIBRARIES} hwloc_bitmap_free "" HAVE_HWLOC_BITMAP)

  set(CMAKE_REQUIRED_INCLUDES ${HWLOC_SAVE_CMAKE_REQUIRED_INCLUDES})
endif()
