cmake_minimum_required(VERSION 3.16)

# =========== SETUP THE PROJECT =============

# Initialize the CMake project.
project(Trexio
	VERSION 2.5.0
	DESCRIPTION "TREX I/O library"
	LANGUAGES C Fortran
	)

# Request the C99 standard.
set(CMAKE_C_STANDARD 99)
set(CMAKE_C_STANDARD_REQUIRED ON)

# Optional configure for developer mode to generate source code from org-mode files.
option(TREXIO_DEVEL "TREXIO developer mode (for code generation)." OFF)
option(TREXIO_TESTS "Whether to perform tests for TREXIO" ON)

if(EXISTS "${PROJECT_SOURCE_DIR}/.devel")
  set(TREXIO_DEVEL ON)
  find_package(Python3 REQUIRED)
  if(Python3_FOUND)
    if(Python3_VERSION_MINOR LESS 6)
      message(FATAL_ERROR "Required Python3 version :: >= 3.6; Found :: ${Python3_VERSION}")
    else()
      message(STATUS "Python3 version :: ${Python3_VERSION}")
    endif()
  endif()
  find_program(EMACS NAMES emacs REQUIRED)
  if(NOT EMACS-NOTFOUND)
    message(STATUS "EMACS detected :: ${EMACS}")
  else()
    message(FATAL_ERROR "EMACS not found. It is required to produce TREXIO source code from org-mode files.")
  endif()
  # in case Git is not available, we default to "unknown"
  set(GIT_HASH "unknown")
  # find Git and if available set GIT_HASH variable
  find_package(Git QUIET)
  if(GIT_FOUND)
    execute_process(
	    COMMAND ${GIT_EXECUTABLE} --no-pager show -s --pretty=format:%H -n 1
	    OUTPUT_VARIABLE GIT_HASH
	    OUTPUT_STRIP_TRAILING_WHITESPACE
	    WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
	    ERROR_QUIET)
  endif()
  # get the user name from the ${USER} env variable
  set(TREXIO_USER_NAME $ENV{USER})
  # replace placeholders in the templace config.h.in file to produce config.h
  # config.h is needed to insert TREXIO_PACKAGE_VERSION and TREXIO_GIT_HASH into trexio.h
  configure_file(${PROJECT_SOURCE_DIR}/include/cmake_config.h.in
                 ${PROJECT_SOURCE_DIR}/include/config.h
		 @ONLY)
endif()

# Set directories to be included at build time.
include_directories(include)

# Add subdirectory with add_library(trexio) specifications.
add_subdirectory(src)

# Add subdirectory with unit tests.
if(TREXIO_TESTS)
  enable_testing()
  add_subdirectory(tests)
endif()