# This file is meant to be included at the project level,
# in order to generate executables compatible with old macOS versions.
# See our `macos-static` CMake preset for how it's meant to be used.

# Note that targeting old enough versions of Mac OS X on recent enough versions of macOS
# triggers some poorly-tested code paths within Apple's linker, which then crashes.
# This can be worked around by using LLVM's LLD linker and passing `-fuse-ld=lld` when linking.

# The `-mmacosx-version-min=10.4` flag ensures that the binary only uses APIs available on Mac OS X 10.4 Tiger.
# The `-arch` flags build a "fat binary" that works on both Apple architectures:
# older Intel x64 Macs and newer ARM "Apple Silicon" ones.
set(secret_sauce -mmacosx-version-min=10.4 "SHELL:-arch x86_64" "SHELL:-arch arm64") # Avoid `-arch` being dedup'd.
add_compile_options(${secret_sauce})
add_link_options(${secret_sauce})
set(PNG_HARDWARE_OPTIMIZATIONS OFF) # These do not play well with a dual-arch build.

# Mac OS X has always provided zlib, so we can safely link dynamically against it.
# However, libpng is *not* provided by default, so we link it statically, which requires downloading and building it from source.
set(PNG_SHARED OFF)
set(PNG_STATIC ON)
# If libpng is already available (e.g. via Homebrew), we ignore that and still build our own.
set(FETCHCONTENT_TRY_FIND_PACKAGE_MODE NEVER)
# But we still want to attempt linking against the system's zlib.
function(rgbds_provide_dependency method dep_name)
  if(dep_name STREQUAL "ZLIB")
    find_package(ZLIB)
    if(ZLIB_FOUND)
      FetchContent_SetPopulated(ZLIB)
    endif()
  endif()
endfunction(rgbds_provide_dependency)
cmake_language(SET_DEPENDENCY_PROVIDER rgbds_provide_dependency
               SUPPORTED_METHODS FETCHCONTENT_MAKEAVAILABLE_SERIAL)
