include(CheckCXXSourceCompiles)
include(CheckIncludeFileCXX)
include(CheckFunctionExists)

find_package(Boost 1.51.0 MODULE
  COMPONENTS
    context
    chrono
    date_time
    filesystem
    program_options
    regex
    system
    thread
  REQUIRED
)
list(APPEND FOLLY_LINK_LIBRARIES ${Boost_LIBRARIES})
list(APPEND FOLLY_INCLUDE_DIRECTORIES ${Boost_INCLUDE_DIRS})

find_package(DoubleConversion MODULE REQUIRED)
list(APPEND FOLLY_LINK_LIBRARIES ${DOUBLE_CONVERSION_LIBRARY})
list(APPEND FOLLY_INCLUDE_DIRECTORIES ${DOUBLE_CONVERSION_INCLUDE_DIR})

set(FOLLY_HAVE_LIBGFLAGS OFF)
find_package(GFlags CONFIG QUIET)
if (gflags_FOUND)
  message(STATUS "Found gflags from package config")
  set(FOLLY_HAVE_LIBGFLAGS ON)
  if (TARGET gflags-shared)
    list(APPEND FOLLY_SHINY_DEPENDENCIES gflags-shared)
  elseif (TARGET gflags)
    list(APPEND FOLLY_SHINY_DEPENDENCIES gflags)
  else()
    message(FATAL_ERROR "Unable to determine the target name for the GFlags package.")
  endif()
  list(APPEND CMAKE_REQUIRED_LIBRARIES ${GFLAGS_LIBRARIES})
  list(APPEND CMAKE_REQUIRED_INCLUDES ${GFLAGS_INCLUDE_DIR})
else()
  find_package(GFlags MODULE)
  set(FOLLY_HAVE_LIBGFLAGS ${LIBGFLAGS_FOUND})
  list(APPEND FOLLY_LINK_LIBRARIES ${LIBGFLAGS_LIBRARY})
  list(APPEND FOLLY_INCLUDE_DIRECTORIES ${LIBGFLAGS_INCLUDE_DIR})
  list(APPEND CMAKE_REQUIRED_LIBRARIES ${LIBGFLAGS_LIBRARY})
  list(APPEND CMAKE_REQUIRED_INCLUDES ${LIBGFLAGS_INCLUDE_DIR})
endif()

set(FOLLY_HAVE_LIBGLOG OFF)
find_package(glog CONFIG QUIET)
if (glog_FOUND)
  message(STATUS "Found glog from package config")
  set(FOLLY_HAVE_LIBGLOG ON)
  list(APPEND FOLLY_SHINY_DEPENDENCIES glog::glog)
else()
  find_package(GLog MODULE)
  set(FOLLY_HAVE_LIBGLOG ${LIBGLOG_FOUND})
  list(APPEND FOLLY_LINK_LIBRARIES ${LIBGLOG_LIBRARY})
  list(APPEND FOLLY_INCLUDE_DIRECTORIES ${LIBGLOG_INCLUDE_DIR})
endif()

find_package(Libevent CONFIG QUIET)
if(TARGET event)
  message(STATUS "Found libevent from package config")
  list(APPEND FOLLY_SHINY_DEPENDENCIES event)
else()
  find_package(LibEvent MODULE REQUIRED)
  list(APPEND FOLLY_LINK_LIBRARIES ${LIBEVENT_LIB})
  list(APPEND FOLLY_INCLUDE_DIRECTORIES ${LIBEVENT_INCLUDE_DIR})
endif()

find_package(OpenSSL MODULE REQUIRED)
list(APPEND FOLLY_LINK_LIBRARIES ${OPENSSL_LIBRARIES})
list(APPEND FOLLY_INCLUDE_DIRECTORIES ${OPENSSL_INCLUDE_DIR})
list(APPEND CMAKE_REQUIRED_LIBRARIES ${OPENSSL_LIBRARIES})
list(APPEND CMAKE_REQUIRED_INCLUDES ${OPENSSL_INCLUDE_DIR})
check_function_exists(ASN1_TIME_diff FOLLY_HAVE_OPENSSL_ASN1_TIME_DIFF)

find_package(ZLIB MODULE)
set(FOLLY_HAVE_LIBZ ${ZLIB_FOUND})
if (ZLIB_FOUND)
  list(APPEND FOLLY_INCLUDE_DIRECTORIES ${ZLIB_INCLUDE_DIRS})
  list(APPEND FOLLY_LINK_LIBRARIES ${ZLIB_LIBRARIES})
endif()

find_package(BZip2 MODULE)
set(FOLLY_HAVE_LIBBZ2 ${BZIP2_FOUND})
if (BZIP2_FOUND)
  list(APPEND FOLLY_INCLUDE_DIRECTORIES ${BZIP2_INCLUDE_DIRS})
  list(APPEND FOLLY_LINK_LIBRARIES ${BZIP2_LIBRARIES})
endif()

find_package(LibLZMA MODULE)
set(FOLLY_HAVE_LIBLZMA ${LIBLZMA_FOUND})
if (LIBLZMA_FOUND)
  list(APPEND FOLLY_INCLUDE_DIRECTORIES ${LIBLZMA_INCLUDE_DIRS})
  list(APPEND FOLLY_LINK_LIBRARIES ${LIBLZMA_LIBRARIES})
endif()

find_package(LZ4 MODULE)
set(FOLLY_HAVE_LIBLZ4 ${LZ4_FOUND})
if (LZ4_FOUND)
  list(APPEND FOLLY_INCLUDE_DIRECTORIES ${LZ4_INCLUDE_DIR})
  list(APPEND FOLLY_LINK_LIBRARIES ${LZ4_LIBRARY})
endif()

find_package(Zstd MODULE)
set(FOLLY_HAVE_LIBZSTD ${ZSTD_FOUND})
if(ZSTD_FOUND)
  list(APPEND FOLLY_INCLUDE_DIRECTORIES ${ZSTD_INCLUDE_DIR})
  list(APPEND FOLLY_LINK_LIBRARIES ${ZSTD_LIBRARY})
endif()

find_package(Snappy MODULE)
set(FOLLY_HAVE_LIBSNAPPY ${SNAPPY_FOUND})
if (SNAPPY_FOUND)
  list(APPEND FOLLY_INCLUDE_DIRECTORIES ${SNAPPY_INCLUDE_DIR})
  list(APPEND FOLLY_LINK_LIBRARIES ${SNAPPY_LIBRARY})
endif()

find_package(LibDwarf)
list(APPEND FOLLY_LINK_LIBRARIES ${LIBDWARF_LIBRARIES})
list(APPEND FOLLY_INCLUDE_DIRECTORIES ${LIBDWARF_INCLUDE_DIRS})

find_package(Libiberty)
list(APPEND FOLLY_LINK_LIBRARIES ${LIBIBERTY_LIBRARIES})
list(APPEND FOLLY_INCLUDE_DIRECTORIES ${LIBIBERTY_INCLUDE_DIRS})

find_package(LibAIO)
list(APPEND FOLLY_LINK_LIBRARIES ${LIBAIO_LIBRARIES})
list(APPEND FOLLY_INCLUDE_DIRECTORIES ${LIBAIO_INCLUDE_DIRS})

list(APPEND FOLLY_LINK_LIBRARIES ${CMAKE_DL_LIBS})
list(APPEND CMAKE_REQUIRED_LIBRARIES ${CMAKE_DL_LIBS})

set(FOLLY_USE_SYMBOLIZER OFF)
CHECK_INCLUDE_FILE_CXX(elf.h FOLLY_HAVE_ELF_H)
find_library(UNWIND_LIBRARIES NAMES unwind)
if (UNWIND_LIBRARIES)
  list(APPEND FOLLY_LINK_LIBRARIES ${UNWIND_LIBRARIES})
  list(APPEND CMAKE_REQUIRED_LIBRARIES ${UNWIND_LIBRARIES})
endif()
check_function_exists(backtrace FOLLY_HAVE_BACKTRACE)
if (FOLLY_HAVE_ELF_H AND FOLLY_HAVE_BACKTRACE AND LIBDWARF_FOUND)
  set(FOLLY_USE_SYMBOLIZER ON)
endif()
message(STATUS "Setting FOLLY_USE_SYMBOLIZER: ${FOLLY_USE_SYMBOLIZER}")

# Using clang with libstdc++ requires explicitly linking against libatomic
check_cxx_source_compiles("
  #include <atomic>
  int main(int argc, char** argv) {
    struct Test { int val; };
    std::atomic<Test> s;
    return static_cast<int>(s.is_lock_free());
  }"
  FOLLY_CPP_ATOMIC_BUILTIN
)
if(NOT FOLLY_CPP_ATOMIC_BUILTIN)
  list(APPEND CMAKE_REQUIRED_LIBRARIES atomic)
  list(APPEND FOLLY_LINK_LIBRARIES atomic)
  check_cxx_source_compiles("
    #include <atomic>
    int main(int argc, char** argv) {
      struct Test { int val; };
      std::atomic<Test> s2;
      return static_cast<int>(s2.is_lock_free());
    }"
    FOLLY_CPP_ATOMIC_WITH_LIBATOMIC
  )
  if (NOT FOLLY_CPP_ATOMIC_WITH_LIBATOMIC)
    message(
      FATAL_ERROR "unable to link C++ std::atomic code: you may need \
      to install GNU libatomic"
    )
  endif()
endif()

option(
  FOLLY_ASAN_ENABLED
  "Build folly with Address Sanitizer enabled."
  OFF
)
if (FOLLY_ASAN_ENABLED)
  if ("${CMAKE_CXX_COMPILER_ID}" MATCHES GNU)
    set(FOLLY_ASAN_ENABLED ON)
    set(FOLLY_ASAN_FLAGS -fsanitize=address,undefined)
    list(APPEND FOLLY_CXX_FLAGS ${FOLLY_ASAN_FLAGS})
    # All of the functions in folly/detail/Sse.cpp are intended to be compiled
    # with ASAN disabled.  They are marked with attributes to disable the
    # sanitizer, but even so, gcc fails to compile them for some reason when
    # sanitization is enabled on the compile line.
    set_source_files_properties(
      "${CMAKE_SOURCE_DIR}/folly/detail/Sse.cpp"
      PROPERTIES COMPILE_FLAGS -fno-sanitize=address,undefined
    )
  elseif ("${CMAKE_CXX_COMPILER_ID}" MATCHES Clang)
    set(FOLLY_ASAN_ENABLED ON)
    set(
      FOLLY_ASAN_FLAGS
      -fno-common
      -fsanitize=address,undefined,integer,nullability
      -fno-sanitize=unsigned-integer-overflow
    )
    list(APPEND FOLLY_CXX_FLAGS ${FOLLY_ASAN_FLAGS})
  endif()
endif()

add_library(folly_deps INTERFACE)
list(REMOVE_DUPLICATES FOLLY_INCLUDE_DIRECTORIES)
target_include_directories(folly_deps INTERFACE ${FOLLY_INCLUDE_DIRECTORIES})
target_link_libraries(folly_deps INTERFACE
  ${FOLLY_LINK_LIBRARIES}
  ${FOLLY_SHINY_DEPENDENCIES}
  ${FOLLY_ASAN_FLAGS}
)