cmake_minimum_required(VERSION 3.16)

file(STRINGS "src/btop.cpp" BTOP_VERSION_LINE REGEX "Version[ \\t\\r\\n]*=[ \\t\\r\\n]*\"[^\"]+\"")
string(REGEX REPLACE "^.*Version[ \\t\\r\\n]*=[ \\t\\r\\n]*\"([^\"]+)\".*$" "\\1" BTOP_VERSION "${BTOP_VERSION_LINE}")

message(STATUS "btop version: ${BTOP_VERSION}")

project(
        "btop"
        VERSION ${BTOP_VERSION}
        DESCRIPTION "Resource monitor that shows usage and stats for processor, memory, disks, network and processes."
        HOMEPAGE_URL "https://github.com/aristocratos/btop"
        LANGUAGES CXX
)

if (CMAKE_SYSTEM_NAME STREQUAL "Linux")
    set(PLATFORM_SRCS_GLOB "src/linux/*.cpp")
elseif (CMAKE_SYSTEM_NAME STREQUAL "FreeBSD")
    set(PLATFORM_SRCS_GLOB "src/freebsd/*.cpp")
elseif (APPLE)
    set(PLATFORM_SRCS_GLOB "src/osx/*.cpp")
else ()
    message(FATAL_ERROR "Unsupported System: ${CMAKE_SYSTEM_NAME}")
endif ()

file(GLOB SRCS CONFIGURE_DEPENDS "src/*.cpp" CONFIGURE_DEPENDS "${PLATFORM_SRCS_GLOB}")

add_executable(btop ${SRCS})

target_include_directories(btop PRIVATE include src)
target_compile_features(btop PUBLIC cxx_std_20)

set(THREADS_PREFER_PTHREAD_FLAG ON)
find_package(Threads REQUIRED)
target_link_libraries(btop PRIVATE Threads::Threads)

include(CheckCXXCompilerFlag)
include(CheckLinkerFlag.cmake)

function(target_compile_options_if_supported)
    list(SUBLIST ARGV 2 -1 COMPILE_OPTIONS)
    foreach (COMPILE_OPTION ${COMPILE_OPTIONS})
        string(MAKE_C_IDENTIFIER ${COMPILE_OPTION} OPTION_ID)
        check_cxx_compiler_flag(${COMPILE_OPTION} CXX_COMPILER_OPTION_CHECK_${OPTION_ID})
        if (CXX_COMPILER_OPTION_CHECK_${OPTION_ID})
            target_compile_options(${ARGV0} ${ARGV1} ${COMPILE_OPTION})
        endif ()
    endforeach ()
endfunction()

function(target_link_options_if_supported)
    list(SUBLIST ARGV 2 -1 LINK_OPTIONS)
    foreach (LINK_OPTION ${LINK_OPTIONS})
        string(MAKE_C_IDENTIFIER ${LINK_OPTION} OPTION_ID)
        check_linker_flag(CXX ${LINK_OPTION} CXX_LINK_OPTION_CHECK_${OPTION_ID})
        if (CXX_LINK_OPTION_CHECK_${OPTION_ID})
            target_link_options(${ARGV0} ${ARGV1} ${LINK_OPTION})
        endif ()
    endforeach ()
endfunction()

target_compile_options_if_supported(btop PRIVATE -Wall -Wextra -pedantic -fcf-protection -cfguard)
target_link_options_if_supported(btop PRIVATE -fexceptions -fstack-protector -fstack-clash-protection)

if (NOT CMAKE_BUILD_TYPE STREQUAL "Debug")
    target_compile_options_if_supported(btop PRIVATE -ftree-loop-vectorize -flto)
    target_link_options_if_supported(btop PRIVATE -flto -s)
endif ()

target_compile_definitions(btop PRIVATE _FORTIFY_SOURCE=2 _GLIBCXX_ASSERTIONS)

if (APPLE)
    target_link_options(btop PRIVATE -framework IOKit -framework CoreFoundation)
endif ()

option(STATIC "statically linked executable" OFF)

if (STATIC)
    set(CMAKE_REQUIRED_LINK_OPTIONS -static -Werror -Wl,--fatal-warnings)
    check_cxx_source_compiles("#include <pwd.h>
		                       int main() { struct passwd* x = getpwuid(0); }" STATIC_GETPWUID)
    if (NOT STATIC_GETPWUID)
        target_compile_definitions(btop PRIVATE STATIC_BUILD)
    endif ()
    target_link_options_if_supported(btop PRIVATE -static -static-libgcc -static-libstdc++)
endif ()

set(CPACK_DEBIAN_PACKAGE_MAINTAINER "Nobody <nobody@nowhere.no>")
set(CPACK_DEBIAN_PACKAGE_SECTION "utils")

include(CPack)

install(
        TARGETS btop RUNTIME
        PERMISSIONS OWNER_READ OWNER_WRITE OWNER_EXECUTE GROUP_READ GROUP_EXECUTE WORLD_READ WORLD_EXECUTE
)
install(
        FILES "README.md"
        DESTINATION "share/btop/"
        PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
)
install(
        FILES "CHANGELOG.md"
        DESTINATION "share/btop/"
        PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
)
install(
        FILES "LICENSE"
        DESTINATION "share/btop/"
        PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
)
install(
        DIRECTORY "themes"
        DESTINATION "share/btop/"
        DIRECTORY_PERMISSIONS OWNER_READ OWNER_WRITE OWNER_EXECUTE GROUP_READ GROUP_EXECUTE WORLD_READ WORLD_EXECUTE
        FILE_PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
)