CMakeLists.txt

PROJECT(kstars CXX C)
set (KStars_VERSION_MAJOR 3)
set (KStars_VERSION_MINOR 5)
set (KStars_VERSION_REVISION 4)
set (KSTARS_BUILD_RELEASE "Beta")
set (CMAKE_CXX_STANDARD 11)

# Build KStars Lite with -DBUILD_KSTARS_LITE=ON
option(BUILD_KSTARS_LITE "Build KStars Lite" OFF)

# Build KStars documentation
option(BUILD_DOC "Build Documentation" ON)

# Fetch translations with -DFETCH_TRANSLATIONS=ON
option(FETCH_TRANSLATIONS "Fetch Translations" OFF)

# minimal requirements
cmake_minimum_required (VERSION 3.4.0 FATAL_ERROR)

# KStars Timestap build
string(TIMESTAMP KSTARS_BUILD_TS UTC)

# For KStars Lite, we ALWAYS need to fetch translations
if(BUILD_KSTARS_LITE)
    SET(FETCH_TRANSLATIONS ON)
endif()

# Set options for fetching translations
if (FETCH_TRANSLATIONS)
SET(KDE_L10N_AUTO_TRANSLATIONS ON)
SET(KDE_L10N_BRANCH "trunk")
endif()

if(BUILD_KSTARS_LITE)
    set (QT_MIN_VERSION "5.7.0") #QtQuickControls 2 is available only in the Qt 5.7.0
else()
    set (QT_MIN_VERSION "5.4.0")
endif()

# Find includes in corresponding build directories
set(CMAKE_INCLUDE_CURRENT_DIR ON)
# Instruct CMake to run moc automatically when needed.
set(CMAKE_AUTOMOC ON)

# Ccache support
IF (ANDROID OR UNIX OR APPLE)
    FIND_PROGRAM(CCACHE_FOUND ccache)
    SET(CCACHE_SUPPORT OFF CACHE BOOL "Enable ccache support")
    IF ((CCACHE_FOUND OR ANDROID) AND CCACHE_SUPPORT MATCHES ON)
        SET_PROPERTY(GLOBAL PROPERTY RULE_LAUNCH_COMPILE ccache)
        SET_PROPERTY(GLOBAL PROPERTY RULE_LAUNCH_LINK ccache)
    ENDIF ()
ENDIF ()

if(CMAKE_SYSTEM_NAME STREQUAL Android)
    add_definitions(-DANDROID -D__STDC_LIMIT_MACROS)
    set(ANDROID TRUE)
endif()

if("${CMAKE_TOOLCHAIN_FILE}" MATCHES "android.toolchain.cmake$")
    include(${CMAKE_BINARY_DIR}/kf5/kde/install/share/ECM/cmake/ECMConfig.cmake)
endif()

find_package(ECM 1.7.0 REQUIRED NO_MODULE)
set(CMAKE_MODULE_PATH ${ECM_MODULE_PATH})
set(CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake/modules" ${CMAKE_MODULE_PATH})

if(BUILD_KSTARS_LITE)
    if("${CMAKE_TOOLCHAIN_FILE}" MATCHES "android.toolchain.cmake$")
        set(QT_ANDROID $ENV{QT_ANDROID})
        set(Qt5Core_DIR "${QT_ANDROID}/lib/cmake/Qt5Core")
        set(Qt5Gui_DIR "${QT_ANDROID}/lib/cmake/Qt5Gui")
        set(Qt5Network_DIR "${QT_ANDROID}/lib/cmake/Qt5Network")
        set(Qt5Positioning_DIR "${QT_ANDROID}/lib/cmake/Qt5Positioning")
        set(Qt5Qml_DIR "${QT_ANDROID}/lib/cmake/Qt5Qml")
        set(Qt5Quick_DIR "${QT_ANDROID}/lib/cmake/Qt5Quick")
        set(Qt5Widgets_DIR "${QT_ANDROID}/lib/cmake/Qt5Widgets")
        include(${QT_ANDROID}/lib/cmake/Qt5/Qt5Config.cmake)
        include(${QT_ANDROID}/lib/cmake/Qt5Core/Qt5CoreConfig.cmake)
        include(${QT_ANDROID}/lib/cmake/Qt5Gui/Qt5GuiConfig.cmake)
        include(${QT_ANDROID}/lib/cmake/Qt5Qml/Qt5QmlConfig.cmake)
        include(${QT_ANDROID}/lib/cmake/Qt5Quick/Qt5QuickConfig.cmake)
        include(${QT_ANDROID}/lib/cmake/Qt5QuickControls2/Qt5QuickControls2Config.cmake)
        include(${QT_ANDROID}/lib/cmake/Qt5Xml/Qt5XmlConfig.cmake)
        include(${QT_ANDROID}/lib/cmake/Qt5Svg/Qt5SvgConfig.cmake)
        include(${QT_ANDROID}/lib/cmake/Qt5Sql/Qt5SqlConfig.cmake)
        include(${QT_ANDROID}/lib/cmake/Qt5Network/Qt5NetworkConfig.cmake)
        include(${QT_ANDROID}/lib/cmake/Qt5Positioning/Qt5PositioningConfig.cmake)
        include(${QT_ANDROID}/lib/cmake/Qt5PositioningQuick/Qt5PositioningQuickConfig.cmake)
        include(${QT_ANDROID}/lib/cmake/Qt5Concurrent/Qt5ConcurrentConfig.cmake)
        include(${QT_ANDROID}/lib/cmake/Qt5AndroidExtras/Qt5AndroidExtrasConfig.cmake)
    else()
        if(ANDROID)
            list(APPEND QT_EXTRA_COMPONENTS AndroidExtras)
        else()
            list(APPEND QT_EXTRA_COMPONENTS PrintSupport)
        endif()
        find_package(Qt5 5.7 REQUIRED COMPONENTS Gui Qml Quick QuickControls2 Xml Svg Sql Network Positioning PositioningQuick Concurrent WebSockets ${QT_EXTRA_COMPONENTS})
    endif()
else()
    #find_package(Qt5 5.4 REQUIRED COMPONENTS Gui Qml Quick Xml Sql Svg Network PrintSupport Positioning Concurrent)
    find_package(Qt5 5.4 REQUIRED COMPONENTS Gui Qml Quick Xml Sql Svg Network PrintSupport Concurrent WebSockets)
endif()
include(ExternalProject)
include(ECMInstallIcons)
include(ECMAddAppIcon)
include(KDEInstallDirs)
include(MacroBoolTo01)
include(ECMQtDeclareLoggingCategory)
include(KDECompilerSettings NO_POLICY_SCOPE)
include(KDECMakeSettings)
include(FeatureSummary)

# Load the frameworks we need
if(BUILD_KSTARS_LITE)
    if("${CMAKE_TOOLCHAIN_FILE}" MATCHES "android.toolchain.cmake$")
        set(KF5_VERSION 5.28.0)
        set(KF5_HOST_TOOLING /usr/lib/x86_64-linux-gnu/cmake/)
        include(${CMAKE_BINARY_DIR}/kf5/kde/install/lib/cmake/KF5Config/KF5ConfigConfig.cmake)
        include(${CMAKE_BINARY_DIR}/kf5/kde/install/lib/cmake/KF5I18n/KF5I18nConfig.cmake)
        include(${CMAKE_BINARY_DIR}/kf5/kde/install/lib/cmake/KF5Plotting/KF5PlottingConfig.cmake)
    else()
        # Find Optional package NotifyConfig for desktop notifications
        find_package(KF5 COMPONENTS NotifyConfig)
        MACRO_BOOL_TO_01(KF5NotifyConfig_FOUND HAVE_NOTIFYCONFIG)

        find_package(KF5 REQUIRED COMPONENTS Auth Config Crash WidgetsAddons NewStuff I18n KIO XmlGui Plotting Notifications)
    endif()
else(BUILD_KSTARS_LITE)
    # Find Optional package NotifyConfig for desktop notifications
    find_package(KF5 COMPONENTS NotifyConfig)
    MACRO_BOOL_TO_01(KF5NotifyConfig_FOUND HAVE_NOTIFYCONFIG)

    find_package(KF5 REQUIRED COMPONENTS
      Auth
      Config
      Crash
      DocTools
      WidgetsAddons
      NewStuff
      I18n
      KIO
      XmlGui
      Plotting
      Notifications
    )
endif(BUILD_KSTARS_LITE)

## Eigen3 Library
find_package(Eigen3 REQUIRED)
add_definitions(${EIGEN_DEFINITIONS})
include_directories(SYSTEM ${EIGEN3_INCLUDE_DIR})

## CFITSIO Library
if(ANDROID)
    if("${CMAKE_TOOLCHAIN_FILE}" MATCHES "android.toolchain.cmake$")
        set(extra_cmake "-DM_LIB=-lm")
    endif()

    find_program(DOS2UNIX dos2unix)
    if (NOT DOS2UNIX)
        message(FATAL_ERROR "Could not find dos2unix")
    endif()

    externalproject_add(cfitsio SOURCE_DIR "${CMAKE_BINARY_DIR}/packaging/android/3rdparty/cfitsio"
        URL https://heasarc.gsfc.nasa.gov/FTP/software/fitsio/c/cfitsio3370.tar.gz
        PATCH_COMMAND bash -c "cd ${CMAKE_BINARY_DIR}/packaging/android/3rdparty/cfitsio && ${DOS2UNIX} ${CMAKE_BINARY_DIR}/packaging/android/3rdparty/cfitsio/CMakeLists.txt && patch -p1 < ${CMAKE_SOURCE_DIR}/packaging/android/3rdparty/cfitsio.patch"
        CMAKE_ARGS -DCMAKE_TOOLCHAIN_FILE=${CMAKE_TOOLCHAIN_FILE} -DBUILD_SHARED_LIBS=OFF -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE} ${extra_cmake}
        BUILD_COMMAND make cfitsio
        BUILD_IN_SOURCE 1
        INSTALL_COMMAND "")

    set(CFITSIO_FOUND TRUE)
    set(CFITSIO_INCLUDE_DIR PUBLIC ${CMAKE_BINARY_DIR}/packaging/android/3rdparty/cfitsio)
    set(CFITSIO_LIBRARIES ${CMAKE_BINARY_DIR}/packaging/android/3rdparty/cfitsio/libcfitsio.a)
else()
    if(BUILD_KSTARS_LITE)
        find_package(CFitsio REQUIRED)
    else()
        find_package(CFitsio)
    endif()
endif()
MACRO_BOOL_TO_01(CFITSIO_FOUND HAVE_CFITSIO)
set_package_properties(CFitsio PROPERTIES DESCRIPTION "FITS IO Library" URL "https://heasarc.gsfc.nasa.gov/fitsio/fitsio.html" TYPE OPTIONAL PURPOSE "Support for the FITS (Flexible Image Transport System) data format in KStars.")

## INDI Library
if (ANDROID)
    set(QT_ANDROID $ENV{QT_ANDROID})
    if("${CMAKE_TOOLCHAIN_FILE}" MATCHES "android.toolchain.cmake$")
        set(extra_cmake -DCMAKE_AR=${ANDROID_NDK}/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-ar)
    endif()
    externalproject_add(indi SOURCE_DIR "${CMAKE_BINARY_DIR}/packaging/android/indi"
        URL https://github.com/indilib/indi/archive/master.zip
        CONFIGURE_COMMAND cmake . -DCMAKE_TOOLCHAIN_FILE=${CMAKE_TOOLCHAIN_FILE} -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE} \\
             -DINDI_BUILD_POSIX_CLIENT=OFF -DINDI_BUILD_SERVER=OFF -DINDI_BUILD_DRIVERS=OFF -DINDI_BUILD_UNITTESTS=OFF \\
             -DINDI_BUILD_DRIVERS=OFF -DINDI_BUILD_QT5_CLIENT=ON -DINDI_CALCULATE_MINMAX=ON \\
             -DCFITSIO_DIR=${CMAKE_BINARY_DIR}/packaging/android/3rdparty/cfitsio -DQT_ANDROID=${QT_ANDROID} -DCMAKE_PREFIX_PATH=${QT_ANDROID} ${extra_cmake}
        BUILD_COMMAND make
        BUILD_IN_SOURCE 1
        INSTALL_COMMAND "")

    set(INDI_FOUND TRUE)
    set(INDI_INCLUDE_DIR ${CMAKE_BINARY_DIR}/packaging/android/indi/libs/indibase ${CMAKE_BINARY_DIR}/packaging/android/indi ${CMAKE_BINARY_DIR}/packaging/android/indi/libs)
    set(INDI_CLIENT_ANDROID_LIBRARIES ${CMAKE_BINARY_DIR}/packaging/android/indi/libindiclientqt.a)
else ()
    find_package(INDI 1.9.0)
endif ()
MACRO_BOOL_TO_01(INDI_FOUND HAVE_INDI)
set_package_properties(INDI PROPERTIES DESCRIPTION "Astronomical instrumentation control" URL "https://www.indilib.org" TYPE OPTIONAL PURPOSE "Support for controlling astronomical devices on Linux with KStars.")

if (INDI_FOUND AND NOT ANDROID)
    find_package(StellarSolver REQUIRED)
endif(INDI_FOUND AND NOT ANDROID)
MACRO_BOOL_TO_01(StellarSolver_FOUND HAVE_STELLARSOLVER)

find_package(Nova)
MACRO_BOOL_TO_01(NOVA_FOUND HAVE_LIBNOVA)
if (NOVA_FOUND)
    include_directories(${NOVA_INCLUDE_DIR})
endif()

## Libraw
if(BUILD_KSTARS_LITE AND ANDROID)
    # OpenMP needed for LibRaw
    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fopenmp -DLIBRAW_USE_OPENMP")
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fopenmp -DLIBRAW_USE_OPENMP")
    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -lgomp")

    externalproject_add(raw SOURCE_DIR "${CMAKE_BINARY_DIR}/packaging/android/3rdparty/libraw"
        URL https://www.libraw.org/data/LibRaw-0.17.2.tar.gz
        PATCH_COMMAND bash -c "cd ${CMAKE_BINARY_DIR}/packaging/android/3rdparty/libraw && wget -qO- https://github.com/LibRaw/LibRaw-cmake/archive/master.zip | jar xvf /dev/stdin && rm -rf cmake && mv -f LibRaw-cmake-master/CMakeLists.txt LibRaw-cmake-master/cmake . && patch -p1 < ${CMAKE_SOURCE_DIR}/packaging/android/3rdparty/libraw.patch"
        CMAKE_ARGS -DCMAKE_TOOLCHAIN_FILE=${CMAKE_TOOLCHAIN_FILE} -DBUILD_SHARED_LIBS=OFF -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE} -DENABLE_OPENMP=OFF -DENABLE_LCMS=OFF
        BUILD_COMMAND make raw
        BUILD_IN_SOURCE 1
        INSTALL_COMMAND "")
    include_directories(${CMAKE_BINARY_DIR}/packaging/android/3rdparty/libraw)
    set(LIBRAW_LIBRARIES ${CMAKE_BINARY_DIR}/packaging/android/3rdparty/libraw/libraw.a)
    set(LibRaw_FOUND true)
else()
    find_package(LibRaw)
endif()
MACRO_BOOL_TO_01(LibRaw_FOUND HAVE_LIBRAW)
set_package_properties(LibRaw PROPERTIES DESCRIPTION "Library for reading RAW files" URL "https://www.libraw.org/" TYPE OPTIONAL PURPOSE "Support for reading and displaying RAW files in KStars.")

## WCS Library
find_package(WCSLIB)
MACRO_BOOL_TO_01(WCSLIB_FOUND HAVE_WCSLIB)
set_package_properties(WCSLIB PROPERTIES DESCRIPTION "World Coordinate System library" URL "https://www.atnf.csiro.au/people/mcalabre/WCS" TYPE OPTIONAL PURPOSE "WCS enables KStars to read and process world coordinate systems in FITS header.")

## XPlanet
find_package(Xplanet)
set_package_properties(Xplanet PROPERTIES DESCRIPTION "Renders an image of all the major planets and most satellites" URL "http://xplanet.sourceforge.net" TYPE RUNTIME PURPOSE "Gives KStars support for xplanet.")

# Qt5 Data Visualization
find_package(Qt5DataVisualization)
MACRO_BOOL_TO_01(Qt5DataVisualization_FOUND HAVE_DATAVISUALIZATION)

## Astrometry.net
#find_package(AstrometryNet)
#set_package_properties(AstrometryNet PROPERTIES DESCRIPTION "Astrometrics Library" URL "http://www.astrometry.net" TYPE RUNTIME PURPOSE "Support for plate solving in KStars.")

## Key Chain
find_package(Qt5Keychain)
MACRO_BOOL_TO_01(Qt5Keychain_FOUND HAVE_KEYCHAIN)

## OpenGL
find_package(OpenGL)
set_package_properties(OpenGL PROPERTIES DESCRIPTION "Open Graphics Library" URL "https://www.opengl.org/" TYPE OPTIONAL PURPOSE "Support for hardware rendering in KStars.")

if (${KF5_VERSION} VERSION_GREATER 5.17.0)
SET(HAVE_KF5WIT 1)
else()
SET(HAVE_KF5WIT 0)
endif()

add_definitions(-DQT_USE_FAST_CONCATENATION -DQT_USE_FAST_OPERATOR_PLUS)
add_definitions(-DQT_NO_URL_CAST_FROM_STRING)
if (CMAKE_BUILD_TYPE STREQUAL "Debug" AND NOT WIN32)
  add_definitions(-DQT_STRICT_ITERATORS)
endif()
add_definitions(-DQT_NO_CAST_TO_ASCII)

# Needed for htmesh, and libraw
kde_enable_exceptions()

if (UNIX)

  # TEMPORARY: To disable QCustomPlot warning until 2.0.0 is released which fixes these warnings
  SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-non-virtual-dtor")

  # Optimize binary size by dropping unneeded symbols at linking stage
  if (${CMAKE_SYSTEM_NAME} MATCHES "Linux")
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fdata-sections -ffunction-sections")
    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--gc-sections")
  endif()
endif(UNIX)

# Optimize binary size by dropping unneeded symbols at linking stage
if (ANDROID)
    SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fdata-sections -ffunction-sections -fvisibility=hidden -fvisibility-inlines-hidden")
    SET(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--gc-sections")
endif ()

# Add security (hardening flags)
IF (UNIX OR APPLE OR ANDROID)
    SET(SEC_COMP_FLAGS "-D_FORTIFY_SOURCE=2 -fstack-protector-all -Wcast-align -fPIE")
    IF (NOT ANDROID AND NOT CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND NOT APPLE)
        SET(SEC_COMP_FLAGS "${SEC_COMP_FLAGS} -Wa,--noexecstack")
    ENDIF ()
    SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${SEC_COMP_FLAGS}")
    SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${SEC_COMP_FLAGS}")
    SET(SEC_LINK_FLAGS "")

    include("${CMAKE_CURRENT_SOURCE_DIR}/cmake/modules/CheckNodump.cmake")
    check_nodump(NODUMP_FLAGS)

    IF (NOT APPLE)
        SET(SEC_LINK_FLAGS "${SEC_LINK_FLAGS} ${NODUMP_FLAGS} -Wl,-z,noexecstack -Wl,-z,relro -Wl,-z,now")
    ENDIF ()
    IF (NOT ANDROID AND NOT APPLE)
        SET(SEC_LINK_FLAGS "${SEC_LINK_FLAGS} -pie")
    ENDIF ()
    SET(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${SEC_LINK_FLAGS}")
    SET(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} ${SEC_LINK_FLAGS}")
ENDIF ()

# Clang Format support
IF (UNIX OR APPLE)
    SET(FORMAT_CODE OFF CACHE BOOL "Enable Clang Format")
    IF (FORMAT_CODE MATCHES ON)
        FILE(GLOB_RECURSE ALL_SOURCE_FILES *.c *.cpp *.h)

        FOREACH(SOURCE_FILE ${ALL_SOURCE_FILES})
            STRING(FIND ${SOURCE_FILE} ${CMAKE_SOURCE_DIR} DIR_FOUND)
            IF (NOT ${DIR_FOUND} EQUAL 0)
                LIST(REMOVE_ITEM ALL_SOURCE_FILES ${SOURCE_FILE})
            ENDIF ()
        ENDFOREACH ()

        FIND_PROGRAM(CLANGFORMAT_EXE NAMES clang-format-5.0)
        IF (CLANGFORMAT_EXE)
            ADD_CUSTOM_TARGET(clang-format COMMAND ${CLANGFORMAT_EXE} -style=file -i ${ALL_SOURCE_FILES})
        ENDIF ()
    ENDIF ()
ENDIF ()

SET(FIX_WARNINGS OFF CACHE BOOL "Enable strict compilation mode to turn compiler warnings to errors")
# Warning, debug and linker flags
IF (UNIX OR APPLE)
    SET(COMP_FLAGS "")
    SET(LINKER_FLAGS "")
    # Verbose warnings and turns all to errors
    SET(COMP_FLAGS "${COMP_FLAGS} -Wall -Wextra")
    IF (FIX_WARNINGS)
        SET(COMP_FLAGS "${COMP_FLAGS} -Werror")
    ENDIF ()
    # Omit problematic warnings
    IF (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
        SET(COMP_FLAGS "${COMP_FLAGS} -Wno-unused-but-set-variable")
    ENDIF ()
    IF (CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 6.9.9)
        SET(COMP_FLAGS "${COMP_FLAGS} -Wno-format-truncation")
    ENDIF ()
    IF (CMAKE_CXX_COMPILER_ID STREQUAL "AppleClang")
        SET(COMP_FLAGS "${COMP_FLAGS} -Wno-nonnull -Wno-deprecated-declarations")
    ENDIF ()
    IF (BUILD_KSTARS_LITE AND "${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
        SET(COMP_FLAGS "${COMP_FLAGS} -Wno-overloaded-virtual")
    ENDIF ()

    SET(COMP_FLAGS "${COMP_FLAGS} -g")

    # Note: The following flags are problematic on older systems with gcc 4.8
    IF (CMAKE_CXX_COMPILER_ID STREQUAL "Clang" OR (CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 4.9.9))
        IF (CMAKE_CXX_COMPILER_ID STREQUAL "Clang" OR CMAKE_CXX_COMPILER_ID STREQUAL "AppleClang")
            SET(COMP_FLAGS "${COMP_FLAGS} -Wno-unused-command-line-argument")
        ENDIF ()
        FIND_PROGRAM(LDGOLD_FOUND ld.gold)
        SET(LDGOLD_SUPPORT OFF CACHE BOOL "Enable ld.gold support")
        # Optional ld.gold is 2x faster than normal ld
        IF (LDGOLD_FOUND AND LDGOLD_SUPPORT MATCHES ON AND NOT APPLE AND NOT CMAKE_SYSTEM_PROCESSOR MATCHES arm)
            SET(LINKER_FLAGS "${LINKER_FLAGS} -fuse-ld=gold")
            # We have Gsl library what is a special case for linking:
            # The gsl library must be linked with cblas. There are two alternatives for this: libcblas or libgslcblas.
            # For example, CMake gets the GSL_LIBRARIES linking flags from the pkgconfig (gsl.pc) file on Ubuntu.
            # This file defines -lgsl -lglscblas for linking flags and if KStars is compiled with Clang, the linker
            # finds out magically that KStars must be linked against glscblas library, but gslcblas is omitted in linking
            # stage if KStars is built with gcc. The linker must be instructed explicitly to link against all libraries
            # passed on command line by -Wl,--no-as-needed.
            SET(LINKER_FLAGS "${LINKER_FLAGS} -Wl,--no-as-needed")
            # Use Identical Code Folding
            SET(COMP_FLAGS "${COMP_FLAGS} -ffunction-sections")
            SET(LINKER_FLAGS "${LINKER_FLAGS} -Wl,--icf=safe")
            # Compress the debug sections
            # Note: Before valgrind 3.12.0, patch should be applied for valgrind (https://bugs.kde.org/show_bug.cgi?id=303877)
            IF (NOT APPLE AND NOT ANDROID AND NOT CMAKE_SYSTEM_PROCESSOR MATCHES arm AND NOT CMAKE_CXX_CLANG_TIDY)
                SET(COMP_FLAGS "${COMP_FLAGS} -Wa,--compress-debug-sections")
                SET(LINKER_FLAGS "${LINKER_FLAGS} -Wl,--compress-debug-sections=zlib")
            ENDIF ()
        ENDIF ()
    ENDIF ()

    # Apply the flags
    SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${COMP_FLAGS}")
    SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${COMP_FLAGS}")
    SET(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${LINKER_FLAGS}")
    SET(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} ${LINKER_FLAGS}")
ENDIF ()

# Sanitizer support
SET(SANITIZERS OFF CACHE BOOL "Sanitizer support for gcc and Clang")
IF (SANITIZERS AND
    ((UNIX AND (CMAKE_CXX_COMPILER_ID STREQUAL "Clang") OR CMAKE_COMPILER_IS_GNUCXX) OR
     (APPLE AND (CMAKE_CXX_COMPILER_ID STREQUAL "AppleClang" OR CMAKE_COMPILER_IS_GNUCXX))))
    SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fsanitize=address,undefined -fno-omit-frame-pointer")
    SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=address,undefined -fno-omit-frame-pointer")
    SET(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -fsanitize=address,undefined -fno-omit-frame-pointer")
    SET(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -fsanitize=address,undefined -fno-omit-frame-pointer")
ENDIF ()

# Unity build support
SET(UNITY_BUILD OFF CACHE BOOL "Enable Unity Build")
INCLUDE(UnityBuild)

configure_file(
    ${CMAKE_CURRENT_SOURCE_DIR}/config-kstars.h.cmake
    ${CMAKE_CURRENT_BINARY_DIR}/config-kstars.h
)

configure_file(${CMAKE_CURRENT_SOURCE_DIR}/kstars/version.h.cmake
               ${CMAKE_CURRENT_BINARY_DIR}/kstars/version.h )

# let our config.h be found first in any case
include_directories (BEFORE ${CMAKE_CURRENT_BINARY_DIR})

if (BUILD_DOC)
    add_subdirectory(doc)
endif()

add_subdirectory(kstars)
add_subdirectory(datahandlers)

IF (NOT ANDROID)
    IF (BUILD_TESTING)
    enable_testing(true)
    add_subdirectory(Tests)
    ENDIF()
    # Make it possible to use the po files fetched by the fetch-translations step
    if (FETCH_TRANSLATIONS)
        ki18n_install("${CMAKE_CURRENT_BINARY_DIR}/po")
    else()
        ki18n_install(po)
        find_package(KF5DocTools CONFIG)
        if(KF5DocTools_FOUND)
            kdoctools_install(po)
        endif()
    endif()
ENDIF ()

install(FILES org.kde.kstars.appdata.xml DESTINATION ${KDE_INSTALL_METAINFODIR})

feature_summary(WHAT ALL FATAL_ON_MISSING_REQUIRED_PACKAGES)

# Only build k5auth for Linux
# JM 2018-09-26: KAuth is disabled due to reliability issues.
#if (${CMAKE_SYSTEM_NAME} MATCHES "Linux")
#    # This helper file is generated to download astrometry.net index files.
#    add_executable(kauth_kstars_helper kstars/auxiliary/downloadhelper.cpp  ${helper_mocs})
#    target_link_libraries(kauth_kstars_helper Qt5::Core)
#    target_link_libraries(kauth_kstars_helper Qt5::Widgets)
#    target_link_libraries(kauth_kstars_helper KF5::Auth)
#    install(TARGETS kauth_kstars_helper DESTINATION ${KAUTH_HELPER_INSTALL_DIR})
#    kauth_install_helper_files(kauth_kstars_helper org.kde.kf5auth.kstars root)
#    kauth_install_actions(org.kde.kf5auth.kstars org.kde.kf5auth.kstars.actions)
#ENDIF ()

# Final package generation
if ("${CMAKE_TOOLCHAIN_FILE}" MATCHES "android.toolchain.cmake$")
    set(EXPORT_DIR "${CMAKE_BINARY_DIR}/packaging/android/kstars_build_apk/")
    set(ANDROID_APK_DIR "${CMAKE_SOURCE_DIR}/packaging/android/apk/")
    set(EXECUTABLE_DESTINATION_PATH "${EXPORT_DIR}/libs/armeabi-v7a/libkstars.so")
    set(ANDROID_NDK $ENV{CMAKE_ANDROID_NDK})
    set(ANDROID_SDK_ROOT $ENV{ANDROID_SDK_ROOT})
    set(ANDROID_API_LEVEL $ENV{ANDROID_API_LEVEL})
    set(ANDROID_TOOLCHAIN arm-linux-androideabi)
    set(ANDROID_GCC_VERSION 4.9)
    set(ANDROID_ABI armeabi-v7a)
    set(_HOST "${CMAKE_HOST_SYSTEM_NAME}-${CMAKE_HOST_SYSTEM_PROCESSOR}")
    string(TOLOWER "${_HOST}" _HOST)
    set(ANDROID_SDK_BUILD_TOOLS_REVISION 21.1.1)
    set(ANDROID_KEYSTORE $ENV{ANDROID_KEYSTORE})
    set(ANDROID_KEYSTORE_ALIAS $ENV{ANDROID_KEYSTORE_ALIAS})
    configure_file("${CMAKE_SOURCE_DIR}/packaging/android/deployment-file.json.in" "${CMAKE_BINARY_DIR}/packaging/android/kstars-deployment.json.in")


    add_custom_target(create-apk-debug-kstars
        COMMAND cmake -E echo "Generating $<TARGET_NAME:kstars> with $<TARGET_FILE_DIR:Qt5::qmake>/androiddeployqt"
        COMMAND cmake -E remove_directory "${EXPORT_DIR}"
        COMMAND cmake -E copy_directory "${CMAKE_SOURCE_DIR}/packaging/android/apk" "${EXPORT_DIR}"
        COMMAND cmake -E copy "$<TARGET_FILE:kstars>" "${EXECUTABLE_DESTINATION_PATH}"
        COMMAND cmake -DINPUT_FILE="${CMAKE_BINARY_DIR}/packaging/android/kstars-deployment.json.in" -DOUTPUT_FILE="${CMAKE_BINARY_DIR}/packaging/android/kstars-deployment.json" "-DTARGET_DIR=${CMAKE_BINARY_DIR}/kstars" "-DTARGET_NAME=kstars" "-DEXPORT_DIR=${CMAKE_INSTALL_PREFIX}" -P ${CMAKE_SOURCE_DIR}/packaging/android/specifydependencies.cmake
        COMMAND $<TARGET_FILE_DIR:Qt5::qmake>/androiddeployqt --input "${CMAKE_BINARY_DIR}/packaging/android/kstars-deployment.json" --output "${EXPORT_DIR}" --android-platform android-${ANDROID_API_LEVEL} --debug --deployment bundled "\\$(ARGS)"
        )
    add_custom_target(create-apk-release-kstars
        COMMAND cmake -E echo "Generating $<TARGET_NAME:kstars> with $<TARGET_FILE_DIR:Qt5::qmake>/androiddeployqt"
        COMMAND cmake -E remove_directory "${EXPORT_DIR}"
        COMMAND cmake -E copy_directory "${CMAKE_SOURCE_DIR}/packaging/android/apk" "${EXPORT_DIR}"
        COMMAND cmake -E copy "$<TARGET_FILE:kstars>" "${EXECUTABLE_DESTINATION_PATH}"
        COMMAND cmake -DINPUT_FILE="${CMAKE_BINARY_DIR}/packaging/android/kstars-deployment.json.in" -DOUTPUT_FILE="${CMAKE_BINARY_DIR}/packaging/android/kstars-deployment.json" "-DTARGET_DIR=${CMAKE_BINARY_DIR}/kstars" "-DTARGET_NAME=kstars" "-DEXPORT_DIR=${CMAKE_INSTALL_PREFIX}" -P ${CMAKE_SOURCE_DIR}/packaging/android/specifydependencies.cmake
        COMMAND $<TARGET_FILE_DIR:Qt5::qmake>/androiddeployqt --input "${CMAKE_BINARY_DIR}/packaging/android/kstars-deployment.json" --output "${EXPORT_DIR}" --android-platform android-${ANDROID_API_LEVEL} --release --deployment bundled "\\$(ARGS)"
        )
    add_custom_target(install-apk-debug-kstars
        COMMAND adb install -r ${CMAKE_BINARY_DIR}/packaging/android/kstars_build_apk//bin/QtApp-debug.apk
        )

    if (ANDROID_KEYSTORE AND ANDROID_KEYSTORE_ALIAS)
        add_custom_target(sign-apk-kstars
            COMMAND jarsigner -verbose -sigalg SHA1withRSA -digestalg SHA1 -keystore ${ANDROID_KEYSTORE} ${CMAKE_BINARY_DIR}/packaging/android/kstars_build_apk/bin/QtApp-release-unsigned.apk ${ANDROID_KEYSTORE_ALIAS}
            COMMAND rm -rf ${CMAKE_BINARY_DIR}/packaging/android/kstars_build_apk/bin/kstars-signed.apk
            COMMAND zipalign -v 4 ${CMAKE_BINARY_DIR}/packaging/android/kstars_build_apk/bin/QtApp-release-unsigned.apk ${CMAKE_BINARY_DIR}/packaging/android/kstars_build_apk/bin/kstars-signed.apk
            )
    endif ()
endif ()