project(rexbacklight)
cmake_minimum_required(VERSION 3.1)
include(CMakeDependentOption)
include(GNUInstallDirs)

set(SCRIPT_DIR ${CMAKE_SOURCE_DIR}/scripts)

#set project include directory
set(INCLUDE_PATH ${CMAKE_SOURCE_DIR}/include)
include_directories("${INCLUDE_PATH}")

set(GIT_VERSION_FILE ${CMAKE_SOURCE_DIR}/include/version.h)
set(GIT_VERSION_TMP_FILE ${CMAKE_SOURCE_DIR}/include/verison.h.tmp)

#require python on windows
#i know this program can't be built on windows, but i wanted to figure out how to do this
if(WIN32)
	find_package(PythonInterp 3 REQUIRED)
else()
	find_package(PythonInterp 3 QUIET)
endif()

if(PYTHONINTERP_FOUND)
	add_custom_command(
		OUTPUT ${GIT_VERSION_TMP_FILE}
		COMMAND ${CMAKE_COMMAND} -E echo "//File generated by CMake. Do not edit!" > ${GIT_VERSION_TMP_FILE}
		COMMAND ${CMAKE_COMMAND} -E echo "#define GIT_TAG_NAME \"v1.5.2\"" > ${GIT_VERSION_TMP_FILE}
		COMMAND ${CMAKE_COMMAND} -E copy_if_different ${GIT_VERSION_TMP_FILE} ${GIT_VERSION_FILE}
		COMMAND ${CMAKE_COMMAND} -E remove ${GIT_VERSION_TMP_FILE}
		WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
		COMMENT "Regenerating version.h"
		VERBATIM
	)
elseif(UNIX)
	add_custom_command(
		OUTPUT ${GIT_VERSION_TMP_FILE}
		COMMAND ${CMAKE_COMMAND} -E echo "//File generated by CMake. Do not edit!" > ${GIT_VERSION_TMP_FILE}
		COMMAND ${CMAKE_COMMAND} -E echo "#define GIT_TAG_NAME \"v1.5.2\"" > ${GIT_VERSION_TMP_FILE}
		COMMAND ${CMAKE_COMMAND} -E copy_if_different ${GIT_VERSION_TMP_FILE} ${GIT_VERSION_FILE}
		COMMAND ${CMAKE_COMMAND} -E remove ${GIT_VERSION_TMP_FILE}
		WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
		COMMENT "Regenerating version.h"
		VERBATIM
	)
endif()

#setup cmake options
option(BUILD_REXLEDCTL "Build led control program" ON)
option(BUILD_REXBACKLIGHT "Build backlight control program" ON)
option(ENABLE_RESTORE_FILE "Enable backlight restoration from generated save file" ON)
option(XBACKLIGHT_COMPAT "Use xbacklight style options (eg -get -inc -dec)" OFF)
CMAKE_DEPENDENT_OPTION(INSTALL_UDEV_LED_RULE "Install the udev rule to allow users of video group to control led devices" ON
	"BUILD_REXLEDCTL" OFF)
CMAKE_DEPENDENT_OPTION(INSTALL_UDEV_BACKLIGHT_RULE "Install the udev rule to allow users of video group to control backlight devices" ON
	"BUILD_REXBACKLIGHT" OFF)
set(UDEV_DIR "/etc/udev/rules.d" CACHE STRING "Set the output directory for udev rules")
mark_as_advanced(UDEV_DIR)

if(XBACKLIGHT_COMPAT)
	add_definitions("-DXBACKLIGHT_COMPAT_OPTIONS")
endif()

#locate rjp library requirements
if(ENABLE_RESTORE_FILE)
	find_package(PkgConfig REQUIRED)
	pkg_check_modules(RJP REQUIRED rjp)
	#temporary library (no actual library generated)
	add_library(common_srcs OBJECT src/cmd.c src/common.c src/restore.c)
	add_definitions("-DENABLE_RESTORE_FILE")
else()
	add_library(common_srcs OBJECT src/cmd.c src/common.c)
endif()
target_sources(common_srcs PUBLIC ${GIT_VERSION_TMP_FILE})

set(CMAKE_C_FLAGS_DEBUG "${CMAKE_C_FLAGS_DEBUG} -DREXBACKLIGHT_DEBUG")

#build led control program
if(BUILD_REXLEDCTL)
	add_executable (rexledctl src/rexbacklight.c)
	add_dependencies(rexledctl common_srcs)                 #force common_srcs to be built first
	target_compile_definitions(rexledctl PRIVATE REXLEDCTL) #define REXLEDCTL in C files
	target_link_libraries(rexledctl PRIVATE $<TARGET_OBJECTS:common_srcs>) #link with the common_srcs "library"
	if(ENABLE_RESTORE_FILE)
		target_link_libraries(rexledctl PRIVATE "${RJP_LIBRARIES}")   #link with rjp
		target_include_directories(rexledctl PUBLIC "${RJP_INCLUDE_DIRS}") #include rjp.h directory
		target_compile_options(rexledctl PUBLIC ${RJP_CFLAGS_OTHER})
	endif()
	install(TARGETS rexledctl RUNTIME DESTINATION bin)
	if(INSTALL_UDEV_LED_RULE)
		install(FILES ${CMAKE_SOURCE_DIR}/rules/91-leds.rules DESTINATION ${UDEV_DIR})
	endif()
endif()
#build backlight control program
if(BUILD_REXBACKLIGHT)
	add_executable (rexbacklight src/rexbacklight.c)
	add_dependencies(rexbacklight common_srcs)
	target_compile_definitions(rexbacklight PRIVATE REXBACKLIGHT)
	target_link_libraries(rexbacklight PRIVATE $<TARGET_OBJECTS:common_srcs>)
	if(ENABLE_RESTORE_FILE)
		target_link_libraries(rexbacklight PRIVATE "${RJP_LIBRARIES}")
		target_include_directories(rexbacklight PUBLIC "${RJP_INCLUDE_DIRS}")
		target_compile_options(rexbacklight PUBLIC ${RJP_CFLAGS_OTHER})
	endif()
	install(TARGETS rexbacklight RUNTIME DESTINATION bin)
	if(INSTALL_UDEV_BACKLIGHT_RULE)
		install(FILES ${CMAKE_SOURCE_DIR}/rules/91-backlight.rules DESTINATION ${UDEV_DIR})
	endif()
endif()

#uninstall target
add_custom_target(uninstall cat install_manifest.txt | xargs rm)