# This files manage third party libraries required by GUDHI

find_package(Boost 1.56.0 REQUIRED COMPONENTS system filesystem unit_test_framework program_options thread)

if(NOT Boost_FOUND)
  message(FATAL_ERROR "NOTICE: This program requires Boost and will not be compiled.")
endif(NOT Boost_FOUND)

# cf. https://cliutils.gitlab.io/modern-cmake/chapters/packages/Boost.html
# This is needed if your Boost version is newer than your CMake version
# or if you have an old version of CMake (<3.5)
if(NOT TARGET Boost::program_options)
    add_library(Boost::program_options IMPORTED INTERFACE)
    set_property(TARGET Boost::program_options PROPERTY
        INTERFACE_INCLUDE_DIRECTORIES ${Boost_INCLUDE_DIR})
    set_property(TARGET Boost::program_options PROPERTY
        INTERFACE_LINK_LIBRARIES ${Boost_LIBRARIES})
endif()
if(NOT TARGET Boost::filesystem)
    add_library(Boost::filesystem IMPORTED INTERFACE)
    set_property(TARGET Boost::filesystem PROPERTY
        INTERFACE_INCLUDE_DIRECTORIES ${Boost_INCLUDE_DIR})
    set_property(TARGET Boost::filesystem PROPERTY
        INTERFACE_LINK_LIBRARIES ${Boost_LIBRARIES})
endif()
if(NOT TARGET Boost::unit_test_framework)
    add_library(Boost::unit_test_framework IMPORTED INTERFACE)
    set_property(TARGET Boost::unit_test_framework PROPERTY
        INTERFACE_INCLUDE_DIRECTORIES ${Boost_INCLUDE_DIR})
    set_property(TARGET Boost::unit_test_framework PROPERTY
        INTERFACE_LINK_LIBRARIES ${Boost_LIBRARIES})
endif()
if(NOT TARGET Boost::system)
    add_library(Boost::system IMPORTED INTERFACE)
    set_property(TARGET Boost::system PROPERTY
        INTERFACE_INCLUDE_DIRECTORIES ${Boost_INCLUDE_DIR})
    set_property(TARGET Boost::system PROPERTY
        INTERFACE_LINK_LIBRARIES ${Boost_LIBRARIES})
endif()

find_package(GMP)
if(GMP_FOUND)
  INCLUDE_DIRECTORIES(${GMP_INCLUDE_DIR})
  find_package(GMPXX)
  if(GMPXX_FOUND)
    INCLUDE_DIRECTORIES(${GMPXX_INCLUDE_DIR})
  endif()
endif()

# In CMakeLists.txt, when include(${CGAL_USE_FILE}), CMAKE_CXX_FLAGS are overwritten.
# cf. http://doc.cgal.org/latest/Manual/installation.html#title40
# A workaround is to include(${CGAL_USE_FILE}) before adding "-std=c++11".
# A fix would be to use https://cmake.org/cmake/help/v3.1/prop_gbl/CMAKE_CXX_KNOWN_FEATURES.html
# or even better https://cmake.org/cmake/help/v3.1/variable/CMAKE_CXX_STANDARD.html
# but it implies to use cmake version 3.1 at least.
find_package(CGAL QUIET)

# Only CGAL versions > 4.11 supports what Gudhi uses from CGAL
if (CGAL_FOUND AND CGAL_VERSION VERSION_LESS 4.11.0)
  message("++ CGAL version ${CGAL_VERSION} is considered too old to be used by Gudhi.")
  unset(CGAL_FOUND)
  unset(CGAL_VERSION)
endif()

if(CGAL_FOUND)
  message(STATUS "CGAL version: ${CGAL_VERSION}.")
  include( ${CGAL_USE_FILE} )
endif()

# For those who dislike bundled dependencies, this indicates where to find a preinstalled Hera.
set(HERA_WASSERSTEIN_INTERNAL_INCLUDE_DIR ${CMAKE_SOURCE_DIR}/ext/hera/wasserstein/include)
set(HERA_WASSERSTEIN_INCLUDE_DIR ${HERA_WASSERSTEIN_INTERNAL_INCLUDE_DIR} CACHE PATH "Directory where one can find Hera's wasserstein.h")
set(HERA_BOTTLENECK_INTERNAL_INCLUDE_DIR ${CMAKE_SOURCE_DIR}/ext/hera/bottleneck/include)
set(HERA_BOTTLENECK_INCLUDE_DIR ${HERA_BOTTLENECK_INTERNAL_INCLUDE_DIR} CACHE PATH "Directory where one can find Hera's bottleneck.h")

option(WITH_GUDHI_USE_TBB "Build with Intel TBB parallelization" ON)

# Find TBB package for parallel sort - not mandatory, just optional.
if(WITH_GUDHI_USE_TBB)
  set(TBB_FIND_QUIETLY ON)
  find_package(TBB)
  if (TBB_FOUND)
    include(${TBB_USE_FILE})
    message("TBB found in ${TBB_LIBRARY_DIRS}")
    add_definitions(-DGUDHI_USE_TBB)
  endif()
endif(WITH_GUDHI_USE_TBB)

set(CGAL_WITH_EIGEN3_VERSION 0.0.0)
find_package(Eigen3 3.1.0)
if (EIGEN3_FOUND)
  include( ${EIGEN3_USE_FILE} )
  set(CGAL_WITH_EIGEN3_VERSION ${CGAL_VERSION})
endif (EIGEN3_FOUND)

# Required programs for unitary tests purpose
FIND_PROGRAM( GCOVR_PATH gcovr )
if (GCOVR_PATH)
  message("gcovr found in ${GCOVR_PATH}")
endif()
FIND_PROGRAM( GPROF_PATH gprof )
if (GPROF_PATH)
  message("gprof found in ${GPROF_PATH}")
endif()
FIND_PROGRAM( DIFF_PATH diff )
if (DIFF_PATH)
  message("diff found in ${DIFF_PATH}")
endif()
FIND_PROGRAM( GNUPLOT_PATH gnuplot )
if (GNUPLOT_PATH)
  message("gnuplot found in ${GNUPLOT_PATH}")
endif()

# BOOST ISSUE result_of vs C++11
add_definitions(-DBOOST_RESULT_OF_USE_DECLTYPE)
# BOOST ISSUE with Libraries name resolution under Windows
add_definitions(-DBOOST_ALL_NO_LIB)
# problem with Visual Studio link on Boost program_options
add_definitions( -DBOOST_ALL_DYN_LINK )
# problem on Mac with boost_system and boost_thread
add_definitions( -DBOOST_SYSTEM_NO_DEPRECATED )

message(STATUS "boost include dirs:" ${Boost_INCLUDE_DIRS})
message(STATUS "boost library dirs:" ${Boost_LIBRARY_DIRS})

# Find the correct Python interpreter.
# Can be set with -DPYTHON_EXECUTABLE=/usr/bin/python3 or -DPython_ADDITIONAL_VERSIONS=3 for instance.
find_package( PythonInterp )

# find_python_module tries to import module in Python interpreter and to retrieve its version number
# returns ${PYTHON_MODULE_NAME_UP}_VERSION and ${PYTHON_MODULE_NAME_UP}_FOUND
function( find_python_module PYTHON_MODULE_NAME )
  string(TOUPPER ${PYTHON_MODULE_NAME} PYTHON_MODULE_NAME_UP)
  execute_process(
          COMMAND ${PYTHON_EXECUTABLE}  -c "import ${PYTHON_MODULE_NAME}; print(${PYTHON_MODULE_NAME}.__version__)"
          RESULT_VARIABLE PYTHON_MODULE_RESULT
          OUTPUT_VARIABLE PYTHON_MODULE_VERSION
          ERROR_VARIABLE PYTHON_MODULE_ERROR)
  if(PYTHON_MODULE_RESULT EQUAL 0)
    # Remove carriage return
    string(STRIP ${PYTHON_MODULE_VERSION} PYTHON_MODULE_VERSION)
    message ("++ Python module ${PYTHON_MODULE_NAME} - Version ${PYTHON_MODULE_VERSION} found")

    set(${PYTHON_MODULE_NAME_UP}_VERSION ${PYTHON_MODULE_VERSION} PARENT_SCOPE)
    set(${PYTHON_MODULE_NAME_UP}_FOUND TRUE PARENT_SCOPE)
  else()
    message ("PYTHON_MODULE_NAME = ${PYTHON_MODULE_NAME}
     - PYTHON_MODULE_RESULT = ${PYTHON_MODULE_RESULT}
     - PYTHON_MODULE_VERSION = ${PYTHON_MODULE_VERSION}
     - PYTHON_MODULE_ERROR = ${PYTHON_MODULE_ERROR}")
    unset(${PYTHON_MODULE_NAME_UP}_VERSION PARENT_SCOPE)
    set(${PYTHON_MODULE_NAME_UP}_FOUND FALSE PARENT_SCOPE)
  endif()
endfunction( find_python_module )

# For modules that do not define module.__version__
function( find_python_module_no_version PYTHON_MODULE_NAME )
  string(TOUPPER ${PYTHON_MODULE_NAME} PYTHON_MODULE_NAME_UP)
  execute_process(
          COMMAND ${PYTHON_EXECUTABLE}  -c "import ${PYTHON_MODULE_NAME}"
          RESULT_VARIABLE PYTHON_MODULE_RESULT
          ERROR_VARIABLE PYTHON_MODULE_ERROR)
  if(PYTHON_MODULE_RESULT EQUAL 0)
    # Remove carriage return
    message ("++ Python module ${PYTHON_MODULE_NAME} found")
    set(${PYTHON_MODULE_NAME_UP}_FOUND TRUE PARENT_SCOPE)
  else()
    message ("PYTHON_MODULE_NAME = ${PYTHON_MODULE_NAME}
     - PYTHON_MODULE_RESULT = ${PYTHON_MODULE_RESULT}
     - PYTHON_MODULE_ERROR = ${PYTHON_MODULE_ERROR}")
    set(${PYTHON_MODULE_NAME_UP}_FOUND FALSE PARENT_SCOPE)
  endif()
endfunction( find_python_module_no_version )

if( PYTHONINTERP_FOUND )
  find_python_module("cython")
  find_python_module("pytest")
  find_python_module("matplotlib")
  find_python_module("numpy")
  find_python_module("scipy")
  find_python_module("sphinx")
  find_python_module("sklearn")
  find_python_module("ot")
  find_python_module("pybind11")
  find_python_module("torch")
  find_python_module("pykeops")
  find_python_module("eagerpy")
  find_python_module_no_version("hnswlib")
endif()

if(NOT GUDHI_PYTHON_PATH)
  message(FATAL_ERROR "ERROR: GUDHI_PYTHON_PATH is not valid.")
endif(NOT GUDHI_PYTHON_PATH)

option(WITH_GUDHI_PYTHON_RUNTIME_LIBRARY_DIRS "Build with setting runtime_library_dirs. Usefull when setting rpath is not allowed" ON)

if(PYTHONINTERP_FOUND AND CYTHON_FOUND)
  if(SPHINX_FOUND)
    # Documentation generation is available through sphinx
    find_program( SPHINX_PATH sphinx-build )

    if(NOT SPHINX_PATH)
      if(PYTHON_VERSION_MAJOR EQUAL 3)
        # In Python3, just hack sphinx-build if it does not exist
        set(SPHINX_PATH "${PYTHON_EXECUTABLE}" "-m" "sphinx.cmd.build")
      endif(PYTHON_VERSION_MAJOR EQUAL 3)
    endif(NOT SPHINX_PATH)
  endif(SPHINX_FOUND)
endif(PYTHONINTERP_FOUND AND CYTHON_FOUND)