# first we can indicate the documentation build as an option and set it to ON by default
option(BUILD_DOC "Build documentation" ON)

# check if Doxygen is installed
find_package(Doxygen)
if (DOXYGEN_FOUND)
    include(FetchContent)
    
    FetchContent_Declare(doxygen-awesome
        GIT_REPOSITORY  https://github.com/jothepro/doxygen-awesome-css.git
        GIT_TAG         v1.5.0
    )
    
    FetchContent_GetProperties(doxygen-awesome)
    if(NOT doxygen-awesome_POPULATED)
      FetchContent_Populate(doxygen-awesome)
    endif()

    
    # set input and output files
    set(DOXYGEN_IN ${CMAKE_CURRENT_SOURCE_DIR}/docs/Doxyfile.in)
    set(DOXYGEN_OUT ${CMAKE_CURRENT_BINARY_DIR}/Doxyfile)

    # request to configure the file
    configure_file(${DOXYGEN_IN} ${DOXYGEN_OUT} @ONLY)
    message("Doxygen build started")

    # note the option ALL which allows to build the docs together with the application
    add_custom_target( doc_doxygen ALL
            COMMAND ${DOXYGEN_EXECUTABLE} ${DOXYGEN_OUT}
            WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
            COMMENT "Generating API documentation with Doxygen"
            VERBATIM )
else (DOXYGEN_FOUND)
    message("Doxygen need to be installed to generate the doxygen documentation")
endif (DOXYGEN_FOUND)
