cmake_minimum_required(VERSION 3.8)

option(LEGACY_OPENGL_LIBS "Use legacy OpenGL libraries instead of glvnd library (Default: off)" OFF)

# Plain and keyword target_link_libraries() signatures cannot be mixed
if (POLICY CMP0023)
  cmake_policy(SET CMP0023 NEW)
endif()

# Honor link flags in try_compile()
if (POLICY CMP0056)
  cmake_policy(SET CMP0056 NEW)
endif()

# only use the additional link flags when linking executables if the
# ENABLE_EXPORTS target property is set to True
if(POLICY CMP0065)
  cmake_policy(SET CMP0065 NEW)
endif()

# Honor language standard (CMAKE_CXX_STANDARD) in try_compile()
if(POLICY CMP0067)
  cmake_policy(SET CMP0067 NEW)
endif()

# Ignore generated source files in AUTOMOC and AUTOUIC
if(POLICY CMP0071)
  cmake_policy(SET CMP0071 OLD)
endif()

# Prefer GLVND or "legacy" OpenGL library (libOpenGL.so vs libGL.so)
if(POLICY CMP0072)
  if(LEGACY_OPENGL_LIBS)
    cmake_policy(SET CMP0072 OLD)
  else()
    cmake_policy(SET CMP0072 NEW)
  endif()
endif()

# Remove leading and trailing whitespace from libraries linked
if(POLICY CMP0004)
  cmake_policy(SET CMP0004 NEW)
endif()

project(celestia VERSION 1.7.0 LANGUAGES C CXX)
set(DISPLAY_NAME "Celestia")
#
#
#
option(ENABLE_CELX    "Enable celx scripting, requires Lua library? (Default: on)" ON)
option(ENABLE_SPICE   "Use spice library? (Default: off)" OFF)
option(ENABLE_NLS     "Enable interface translation? (Default: on)" ON)
option(ENABLE_GLUT    "Build simple Glut frontend? (Default: off)" OFF)
option(ENABLE_GTK     "Build GTK2 frontend (Unix only)? (Default: off)" OFF)
option(ENABLE_QT      "Build Qt frontend? (Default: on)" ON)
option(ENABLE_SDL     "Build SDL frontend? (Default: off)" OFF)
option(ENABLE_WIN     "Build Windows native frontend? (Default: on)" ON)
option(ENABLE_FFMPEG  "Support video capture using FFMPEG (Default: off)" OFF)
option(ENABLE_TOOLS   "Build different tools? (Default: off)" OFF)
option(NATIVE_OSX_APP "Support native OSX paths read data from (Default: off)" OFF)
option(FAST_MATH      "Build with unsafe fast-math compiller option (Default: off)" OFF)
option(ENABLE_TESTS   "Enable unit tests? (Default: off)" OFF)
option(ENABLE_GLES    "Build for OpenGL ES 2.0 instead of OpenGL 2.1 (Default: off)" OFF)
option(USE_GTKGLEXT   "Use libgtkglext1 for GTK2 frontend (Default: on)" ON)
option(USE_QT6        "Use Qt6 in Qt frontend (Default: off)" OFF)
option(USE_GTK3       "Use Gtk3 in GTK2 frontend (Default: off)" OFF)

if(ENABLE_GLES)
  add_definitions(-DGL_ES)
  # Disable USE_GTKGLEXT if using OpenGL ES
  set(USE_GTKGLEXT OFF)
endif()

if(USE_GTK3)
  # Disable USE_GTKGLEXT if using Gtk+3
  set(USE_GTKGLEXT OFF)
endif()

if(NOT CMAKE_BUILD_TYPE)
  set(CMAKE_BUILD_TYPE "Release" CACHE STRING "Build type." FORCE)
endif()

set(CMAKE_INCLUDE_CURRENT_DIR ON)

if(UNIX AND (NOT CYGWIN))
  set(_UNIX true)
endif()

# _USE_MATH_DEFINES enables use of math constants like M_PI,
# which are by default disabled in standard C++ mode (like std=c++11 instead of std=gnu11)
add_definitions(-D_USE_MATH_DEFINES)

# Let CMake handle setting C++11 (since 3.1)
if(NOT CMAKE_CXX_STANDARD)
  set(CMAKE_CXX_STANDARD 17)
endif()
set(CMAKE_C_STANDARD 11)

# Use our cmake files
list(INSERT CMAKE_MODULE_PATH 0 "${CMAKE_CURRENT_SOURCE_DIR}/cmake")

if((NOT WIN32) AND (NOT NATIVE_OSX_APP))
  include(GNUInstallDirs)
  include(rpath)
endif()
include(CheckIncludeFiles)
include(CheckIncludeFileCXX)
include(FastMath)

#
# Compile options
#
if(MSVC)
  # CMake 3.14 and below set warning flags by default, remove them to prevent conflicts
  string(REGEX REPLACE "/W[3|4]" "" CMAKE_C_FLAGS "${CMAKE_C_FLAGS}")
  string(REGEX REPLACE "/W[3|4]" "" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")

  # Disabled warnings
  # C4244, C4267, C4503: implicit type conversion to a smaller type
  # C4786: long names in templates
  # C4800: forcing value to bool
  # C4455: reserved literals (no undescore at the beginning)
  # C5030: not recognized attribute
  # C5105: macro expansion producing 'defined' has undefined behavior
  # Additional options
  # bigobj: generate more object sections than allowed by default
  # Promoted to errors
  # C4316: object allocated on the heap may not be aligned 16
  add_compile_options("/wd4244" "/wd4267" "/wd4503" "/wd4800" "/wd4455" "/wd5030" "/wd5105" "/bigobj" "/we4316")

  if(MSVC_VERSION GREATER_EQUAL 1914)
    # /Zc:__cplusplus: correctly set __cplusplus macro value
    add_compile_options("/Zc:__cplusplus")
  endif()
endif()

if(NOT WIN32)
  # Qt requires -fPIC, so build all code with it
  # It's always set on windows
  add_compile_options(-fPIC)
endif()

if(MINGW)
  # MinGW has a bug which causes too many false-positive warnings
  # for 'operator!='
  add_compile_options(-Wno-attributes)
endif()

EnableFastMath(${FAST_MATH})

#
# NLS (Gettext) support
#
if(ENABLE_NLS)
  find_package(Gettext)
  if(NOT GETTEXT_FOUND)
    message(WARNING "Gettext is not found, traslations won't be created.")
  endif()
  include(FixGettext)

  find_package(Intl REQUIRED)
  include_directories(${Intl_INCLUDE_DIRS})
  link_libraries(${Intl_LIBRARIES})
  add_definitions(-DENABLE_NLS)
else()
  message(STATUS "NLS is disabled. Not looking for gettext and libintl.")
endif()

if(ENABLE_SPICE)
  find_package(CSPICE)
  if(NOT CSPICE_FOUND)
    message(STATUS "Using cspice submodule")
    add_subdirectory("${CMAKE_SOURCE_DIR}/thirdparty/Spice")
    get_target_property(SPICE_INCLUDE_DIR spice INCLUDE_DIRECTORIES)
    include_directories(${SPICE_INCLUDE_DIR})
    message(STATUS "Spice include directories: ${SPICE_INCLUDE_DIR}")
    add_library(CSPICE::CSPICE ALIAS spice)
  else()
    include_directories(${CSPICE_INCLUDE_DIR})
  endif()
  add_definitions(-DUSE_SPICE)
else()
  message(STATUS "NAIF SPICE is disabled. Not looking for cspice library.")
endif()

if(ENABLE_FFMPEG)
  include(FindFFMPEG)
  find_package(FFMPEG REQUIRED COMPONENTS avcodec avutil avformat swscale)
  include_directories(${FFMPEG_INCLUDE_DIRS})
  add_definitions(-DUSE_FFMPEG)
endif()

if(ENABLE_LIBAVIF)
  find_package(Libavif REQUIRED)
  link_libraries(libavif::libavif)
  include_directories(${LIBAVIF_INCLUDE_DIR})
  add_definitions(-DUSE_LIBAVIF)
endif()

if(_UNIX)
  find_package(PkgConfig)
endif()

if(WIN32)
  link_libraries("vfw32" "comctl32" "winmm")
endif()

if(NOT ENABLE_GLES)
  find_package(OpenGL REQUIRED)
  include_directories(${OPENGL_INCLUDE_DIRS})
  link_libraries(${OPENGL_LIBRARIES})
endif()

find_package(Libepoxy REQUIRED)
link_libraries(libepoxy::libepoxy)
include_directories(${LIBEPOXY_INCLUDE_DIR})

find_package(Eigen3 3.3 REQUIRED NO_MODULE) # -DEigen3_DIR=...
message(STATUS "Found Eigen3 ${EIGEN3_VERSION_STRING}")
link_libraries(Eigen3::Eigen)

find_package(fmt 6.1.0 CONFIG QUIET)
if(NOT fmt_FOUND)
  message(STATUS "Using fmt submodule")
  add_subdirectory("${CMAKE_SOURCE_DIR}/thirdparty/fmt")
endif()
link_libraries(fmt::fmt)

find_package(PNG REQUIRED)
add_definitions(${PNG_DEFINITIONS})
link_libraries(PNG::PNG)

find_package(JPEG REQUIRED) # -DJPEG_LIBRARY=...
include_directories(${JPEG_INCLUDE_DIRS})
link_libraries(${JPEG_LIBRARIES})

if(ENABLE_CELX)
  add_definitions(-DCELX)

  find_package(LuaJIT)
  if(NOT LUAJIT_FOUND)
    find_package(Lua REQUIRED)
  endif()
  include_directories(${LUA_INCLUDE_DIR})
  link_libraries(${LUA_LIBRARIES})
else()
  message(STATUS "CELX is disabled. Not looking for LUA libraries.")
endif()

find_package(Freetype REQUIRED)
link_libraries(Freetype::Freetype)

find_package(meshoptimizer CONFIG QUIET)
if(meshoptimizer_FOUND)
  message(STATUS "Found meshoptimizer library")
  set(HAVE_MESHOPTIMIZER 1)
else()
  message(STATUS "meshoptimizer library is missing")
endif()

#[[
get_cmake_property(_variableNames VARIABLES)
list (SORT _variableNames)
foreach (_variableName ${_variableNames})
    message(STATUS "${_variableName}=${${_variableName}}")
endforeach()
]]#

# macOS Bundling
if(NATIVE_OSX_APP)
  message(STATUS "Generating Info.plist for macOS Bundle")
  configure_file(${CMAKE_SOURCE_DIR}/Info.plist.in ${CMAKE_BINARY_DIR}/Info.plist @ONLY)
endif()

if(NATIVE_OSX_APP)
  set(CMAKE_INSTALL_PREFIX "${PROJECT_BINARY_DIR}/${PROJECT_NAME}.app/Contents")
  set(CMAKE_INSTALL_FULL_LOCALEDIR "${CMAKE_INSTALL_PREFIX}/Resources/locale")
  set(CMAKE_INSTALL_BINDIR "MacOS")
  set(DATADIR "${CMAKE_INSTALL_PREFIX}/Resources")
  set(FULL_DATADIR "${CMAKE_INSTALL_PREFIX}/Resources")
elseif(WIN32)
  set(CMAKE_INSTALL_BINDIR ".")
  set(CMAKE_INSTALL_DATAROOTDIR ".")
  set(CMAKE_INSTALL_DATADIR ".")
  set(CMAKE_INSTALL_FULL_LOCALEDIR "locale")
  set(DATADIR "${CMAKE_INSTALL_DATADIR}")
  set(FULL_DATADIR ".")
else()
  set(DATADIR "${CMAKE_INSTALL_DATADIR}/${PROJECT_NAME}")
  set(FULL_DATADIR "${CMAKE_INSTALL_FULL_DATADIR}/${PROJECT_NAME}")
endif()

if(NOT GIT_COMMIT)
  find_program(GIT_FOUND git)
  if(GIT_FOUND)
    execute_process(
      COMMAND git log --pretty=format:%h -1
      WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}"
      OUTPUT_VARIABLE GIT_COMMIT
    )
    if("${GIT_COMMIT}" STREQUAL "")
      set(GIT_COMMIT "unknown")
    endif()
  else()
    set(GIT_COMMIT "unknown")
  endif()
endif()

#
# Compile definitions
#
add_definitions(
  -DVERSION="${PROJECT_VERSION}"
  -DPACKAGE="celestia"
  -DGIT_COMMIT="${GIT_COMMIT}"
)

if(NOT NATIVE_OSX_APP)
  add_definitions(
    -DLOCALEDIR="${CMAKE_INSTALL_FULL_LOCALEDIR}"
    -DCONFIG_DATA_DIR="${FULL_DATADIR}"
    -DHIP_DATA_DIR="${FULL_DATADIR}"
    -DSPLASH_DIR="${FULL_DATADIR}/splash"
  )
endif()

if(WIN32)
  add_definitions(
    -D_CRT_SECURE_NO_WARNINGS
    -D_SCL_SECURE_NO_WARNINGS
    -DNOMINMAX
    -DWIN32_LEAN_AND_MEAN
    -DWINVER=0x0601
    -D_WIN32_WINNT=0x0601
  )
  # Fix the issue: https://github.com/CelestiaProject/Celestia/issues/364
  add_definitions(-D_ENABLE_EXTENDED_ALIGNED_STORAGE)
endif()

if(APPLE)
  if(NATIVE_OSX_APP)
    add_definitions(-DNATIVE_OSX_APP)
  endif()
  add_definitions(-DGL_SILENCE_DEPRECATION)
endif()

string(TOLOWER "${CMAKE_BUILD_TYPE}" build_type_lc)
if("${build_type_lc}" STREQUAL "debug")
  add_definitions(-D_DEBUG -DDEBUG)
else()
  add_definitions(-DNO_DEBUG -DEIGEN_NO_DEBUG)
  if(NOT MSVC)
    add_compile_options(
      $<$<COMPILE_LANGUAGE:CXX>:-fno-rtti>
      $<$<COMPILE_LANGUAGE:CXX>:-fno-exceptions>
    )
  endif()
endif()

# Turning all debug on dramatically decreases performance
if(OCTREE_DEBUG)
  add_definitions(-DOCTREE_DEBUG)
endif()

include_directories("${CMAKE_SOURCE_DIR}/src" ${CMAKE_BINARY_DIR})

# configure a header file to pass some of the CMake settings
# to the source code
include(CheckSymbolExists)
check_symbol_exists(wordexp wordexp.h HAVE_WORDEXP)
check_include_files(byteswap.h HAVE_BYTESWAP_H)

find_package(Filesystem REQUIRED COMPONENTS Final Experimental)
if(CXX_FILESYSTEM_IS_EXPERIMENTAL)
  message(WARNING "C++ lacks header <filesystem>, using <experimental/filesystem> instead.")
else()
  set(HAVE_STD_FILESYSTEM ON)
endif()
link_libraries(std::filesystem)

try_compile(HAVE_CHARCONV ${CMAKE_BINARY_DIR} "${CMAKE_SOURCE_DIR}/checks/cxxccint.cpp")
if(HAVE_CHARCONV)
  try_compile(HAVE_FLOAT_CHARCONV ${CMAKE_BINARY_DIR} "${CMAKE_SOURCE_DIR}/checks/cxxccfloat.cpp")
  if(NOT HAVE_FLOAT_CHARCONV)
    message(WARNING "C++ charconv lacks floating point support!\nWill use own implementation.")
  endif()
else()
  message(WARNING "C++ charconv is unusable!\nWill use own implementation.")
endif()

include(TestBigEndian)
test_big_endian(WORDS_BIGENDIAN)

configure_file("config.h.in" "config.h")

set(BASE_DATA_SOURCES
  demo.cel
  guide.cel
  start.cel
  celestia.cfg
  controls.txt
)
install(FILES ${BASE_DATA_SOURCES} DESTINATION ${DATADIR})
install(FILES "splash.png" DESTINATION "${DATADIR}/splash")

if(NATIVE_OSX_APP)
  install(FILES ${CMAKE_BINARY_DIR}/Info.plist DESTINATION .)
endif()

add_subdirectory(src)
add_subdirectory(po)
add_subdirectory(fonts)
add_subdirectory(images)
add_subdirectory(locale)
add_subdirectory(scripts)
add_subdirectory(shaders)

if(ENABLE_TESTS)
  enable_testing()
  add_subdirectory(test)
endif()