cmake/FindCHOLMOD.cmake

# CHOLMOD lib usually requires linking to a blas and lapack library.
# It is up to the user of this module to find a BLAS and link to it.
#
# This module first tries to find CHOLMOD via its CMake config-mode package
# (shipped with SuiteSparse >= 7.0). If that fails, it falls back to a
# manual header/library search for compatibility with older installations.
# SPDX-FileCopyrightText: The Eigen Authors
# SPDX-License-Identifier: MPL-2.0

if (CHOLMOD_INCLUDES AND CHOLMOD_LIBRARIES)
  set(CHOLMOD_FIND_QUIETLY TRUE)
endif ()

# --- Try config-mode first (SuiteSparse >= 7.0) ---
if(NOT CHOLMOD_INCLUDES OR NOT CHOLMOD_LIBRARIES)
  find_package(CHOLMOD CONFIG QUIET)
  if(CHOLMOD_FOUND AND TARGET SuiteSparse::CHOLMOD)
    # Extract include dirs and libraries from the imported target so that the
    # legacy variables expected by Eigen's build system are populated.
    get_target_property(_cholmod_inc SuiteSparse::CHOLMOD INTERFACE_INCLUDE_DIRECTORIES)
    if(_cholmod_inc)
      set(CHOLMOD_INCLUDES "${_cholmod_inc}" CACHE PATH "CHOLMOD include directory")
    endif()
    set(CHOLMOD_LIBRARIES SuiteSparse::CHOLMOD CACHE STRING "CHOLMOD libraries")
    # Mark as found and return early -- no need for the manual search below.
    mark_as_advanced(CHOLMOD_INCLUDES CHOLMOD_LIBRARIES)
    return()
  endif()
endif()

# --- Fallback: manual search (SuiteSparse < 7.0 or no config package) ---
find_path(CHOLMOD_INCLUDES
  NAMES
  cholmod.h
  PATHS
  $ENV{CHOLMODDIR}
  ${INCLUDE_INSTALL_DIR}
  PATH_SUFFIXES
  suitesparse
  ufsparse
)

find_library(CHOLMOD_LIBRARIES cholmod PATHS $ENV{CHOLMODDIR} ${LIB_INSTALL_DIR})

if(CHOLMOD_LIBRARIES)

  get_filename_component(CHOLMOD_LIBDIR ${CHOLMOD_LIBRARIES} PATH)

  find_library(AMD_LIBRARY amd PATHS ${CHOLMOD_LIBDIR} $ENV{CHOLMODDIR} ${LIB_INSTALL_DIR})
  if (AMD_LIBRARY)
    set(CHOLMOD_LIBRARIES ${CHOLMOD_LIBRARIES} ${AMD_LIBRARY})
  else ()
    set(CHOLMOD_LIBRARIES FALSE)
  endif ()

endif()

if(CHOLMOD_LIBRARIES)

  find_library(COLAMD_LIBRARY colamd PATHS ${CHOLMOD_LIBDIR} $ENV{CHOLMODDIR} ${LIB_INSTALL_DIR})
  if (COLAMD_LIBRARY)
    set(CHOLMOD_LIBRARIES ${CHOLMOD_LIBRARIES} ${COLAMD_LIBRARY})
  else ()
    set(CHOLMOD_LIBRARIES FALSE)
  endif ()

endif()

if(CHOLMOD_LIBRARIES)

  find_library(CAMD_LIBRARY camd PATHS ${CHOLMOD_LIBDIR} $ENV{CHOLMODDIR} ${LIB_INSTALL_DIR})
  if (CAMD_LIBRARY)
    set(CHOLMOD_LIBRARIES ${CHOLMOD_LIBRARIES} ${CAMD_LIBRARY})
  else ()
    set(CHOLMOD_LIBRARIES FALSE)
  endif ()

endif()

if(CHOLMOD_LIBRARIES)

  find_library(CCOLAMD_LIBRARY ccolamd PATHS ${CHOLMOD_LIBDIR} $ENV{CHOLMODDIR} ${LIB_INSTALL_DIR})
  if (CCOLAMD_LIBRARY)
    set(CHOLMOD_LIBRARIES ${CHOLMOD_LIBRARIES} ${CCOLAMD_LIBRARY})
  else ()
    set(CHOLMOD_LIBRARIES FALSE)
  endif ()

endif()

if(CHOLMOD_LIBRARIES)

  find_library(CHOLMOD_METIS_LIBRARY metis PATHS ${CHOLMOD_LIBDIR} $ENV{CHOLMODDIR} ${LIB_INSTALL_DIR})
  if (CHOLMOD_METIS_LIBRARY)
    set(CHOLMOD_LIBRARIES ${CHOLMOD_LIBRARIES} ${CHOLMOD_METIS_LIBRARY})
  endif ()

endif()

if(CHOLMOD_LIBRARIES)

  find_library(SUITESPARSE_LIBRARY SuiteSparse PATHS ${CHOLMOD_LIBDIR} $ENV{CHOLMODDIR} ${LIB_INSTALL_DIR})
  if (SUITESPARSE_LIBRARY)
    set(CHOLMOD_LIBRARIES ${CHOLMOD_LIBRARIES} ${SUITESPARSE_LIBRARY})
  endif ()

endif()

include(FindPackageHandleStandardArgs)
find_package_handle_standard_args(CHOLMOD DEFAULT_MSG
                                  CHOLMOD_INCLUDES CHOLMOD_LIBRARIES)

mark_as_advanced(CHOLMOD_INCLUDES CHOLMOD_LIBRARIES AMD_LIBRARY COLAMD_LIBRARY SUITESPARSE_LIBRARY CAMD_LIBRARY CCOLAMD_LIBRARY CHOLMOD_METIS_LIBRARY)