macro(ADD_TO_ALLOPTIONS _NEWNAME)
  list(APPEND ALLOPTIONS ${_NEWNAME})
  string(LENGTH ${_NEWNAME} _SLEN)
  if(${LONGESTOPTIONNAME} LESS ${_SLEN})
    set(LONGESTOPTIONNAME ${_SLEN})
  endif()
endmacro()

macro(SET_OPTION _NAME _DESC)
  add_to_alloptions(${_NAME})
  if(${ARGC} EQUAL 3)
    set(_DEFLT ${ARGV2})
  else()
    set(_DEFLT OFF)
  endif()
  option(${_NAME} ${_DESC} ${_DEFLT})
endmacro()

macro(DEP_OPTION _NAME _DESC _DEFLT _DEPTEST _FAILDFLT)
  add_to_alloptions("${_NAME}")
  cmake_dependent_option("${_NAME}" "${_DESC}" "${_DEFLT}" "${_DEPTEST}" "${_FAILDFLT}")
endmacro()

macro(OPTION_STRING _NAME _DESC _VALUE)
  add_to_alloptions(${_NAME})
  set(${_NAME} ${_VALUE} CACHE STRING "${_DESC}")
  set(HAVE_${_NAME} ${_VALUE})
ENDMACRO()

# Message Output
macro(MESSAGE_WARN _TEXT)
  message(WARNING "${_TEXT}")
endmacro()

macro(MESSAGE_ERROR _TEXT)
  message(FATAL_ERROR "*** ERROR: ${_TEXT}")
endmacro()

macro(MESSAGE_BOOL_OPTION _NAME _VALUE)
  if(${_VALUE})
    message(STATUS "  ${_NAME}:\tON")
  else()
    message(STATUS "  ${_NAME}:\tOFF")
  endif()
endmacro()

macro(MESSAGE_TESTED_OPTION _NAME)
  set(_REQVALUE ${${_NAME}})
  set(_PAD " ")
  if(${ARGC} EQUAL 2)
    set(_PAD ${ARGV1})
  endif()
  string(SUBSTRING "${_NAME}" 0 4 _NAMESTART)
  if(_NAMESTART STREQUAL "SDL_")
    string(SUBSTRING "${_NAME}" 4 -1 _STRIPPEDNAME)
  else()
    set(_STRIPPEDNAME "${_NAME}")
  endif()
  if(NOT HAVE_${_STRIPPEDNAME})
    set(HAVE_${_STRIPPEDNAME} OFF)
  elseif("${HAVE_${_STRIPPEDNAME}}" MATCHES "1|TRUE|YES|Y")
    set(HAVE_${_STRIPPEDNAME} ON)
  endif()
  message(STATUS "  ${_NAME}${_PAD}(Wanted: ${_REQVALUE}): ${HAVE_${_STRIPPEDNAME}}")
endmacro()

function(LISTTOSTR _LIST _OUTPUT)
  if(${ARGC} EQUAL 3)
    # prefix for each element
    set(_LPREFIX ${ARGV2})
  else()
    set(_LPREFIX "")
  endif()
  # Do not use string(REPLACE ";" " ") here to avoid messing up list
  # entries
  set(res)
  foreach(_ITEM ${${_LIST}})
    set(res "${res} ${_LPREFIX}${_ITEM}")
  endforeach()
  set(${_OUTPUT} "${res}" PARENT_SCOPE)
endfunction()

macro(LISTTOSTRREV _LIST _OUTPUT)
  if(${ARGC} EQUAL 3)
    # prefix for each element
    set(_LPREFIX ${ARGV2})
  else()
    set(_LPREFIX "")
  endif()
  # Do not use string(REPLACE ";" " ") here to avoid messing up list
  # entries
  foreach(_ITEM ${${_LIST}})
    set(${_OUTPUT} "${_LPREFIX}${_ITEM} ${${_OUTPUT}}")
  endforeach()
endmacro()

if(CMAKE_VERSION VERSION_LESS 3.16.0 OR SDL2_SUBPROJECT)
  # - CMake versions <3.16 do not support the OBJC language
  # - When SDL is built as a subproject and when the main project does not enable OBJC,
  #   CMake fails due to missing internal CMake variables (CMAKE_OBJC_COMPILE_OBJECT)
  #   (reproduced with CMake 3.24.2)
  macro(CHECK_OBJC_SOURCE_COMPILES SOURCE VAR)
    set(PREV_REQUIRED_DEFS "${CMAKE_REQUIRED_DEFINITIONS}")
    set(CMAKE_REQUIRED_DEFINITIONS "-x objective-c ${PREV_REQUIRED_DEFS}")
    CHECK_C_SOURCE_COMPILES("${SOURCE}" ${VAR})
    set(CMAKE_REQUIRED_DEFINITIONS "${PREV_REQUIRED_DEFS}")
  endmacro()
else()
  include(CheckOBJCSourceCompiles)
  if (APPLE)
      enable_language(OBJC)
  endif()
endif()

if(APPLE)
  check_language(OBJC)
  if(NOT CMAKE_OBJC_COMPILER)
    message(WARNING "Cannot find working OBJC compiler.")
  endif()
endif()

if(CMAKE_VERSION VERSION_LESS 3.13.0)
  macro(target_link_directories _TARGET _SCOPE)
    link_directories(${ARGN})
  endmacro()
endif()