PHP_ARG_ENABLE(arma,           for armadillo support,
[  --enable-arma            Enable armadillo support])

PHP_ARG_ENABLE(arma-operators, for operator overloading support in armadillo,
[  --enable-arma-operators  Enable operator overloading for armadillo ], no, no)

PHP_ARG_ENABLE(arma-pch,       build PCH header of armadillo,
[  --enable-arma-pch        Enable building PCH header of armadillo ], no, no)

if test "$PHP_ARMA" != "no"; then
  PHP_REQUIRE_CXX()

  # If enabled, try building pre-compiled header for armadillo.
  if test "$PHP_ARMA_PCH" != "no"; then
    CXX_INCLEDE_PATHS=($(echo | $CXX -xc++ -E -v - 2>&1 | grep -p '^ /'))
    PHP_INCLUDES=`php-config --includes`
    PCH_FILE='./build/armadillo.gch'
    # Note that '-D' option is valid when compiling PCH header, but not when using it.
    CXX_TMP_COMPILE_FLAGS="-std=c++17 -x c++-header $PHP_INCLUDES -DARMA_DONT_PRINT_ERRORS"
    if test -z "$PHP_DEBUG"; then
      CXX_TMP_COMPILE_FLAGS+=' -O2'
    else
      CXX_TMP_COMPILE_FLAGS+=' -g -O0'
    fi
  fi
  for TEMP_INCLUDE_DIR in "$CXX_INCLEDE_PATHS"; do
    ARMADILLO_HEADER_FILE=$TEMP_INCLUDE_DIR/armadillo
    if test -f "$ARMADILLO_HEADER_FILE"; then
      $CXX $CXX_TMP_COMPILE_FLAGS $TEMP_INCLUDE_DIR/armadillo -o $PCH_FILE
      break
    fi
  done

  # Include PCH file if valid.
  EXTRA_CXXFLAGS="-std=c++17 -DARMA_DONT_PRINT_ERRORS"
  CLANG_TEST_STR=`$CXX --version | grep clang`
  if test -f "$PCH_FILE"; then
    if test -n "$CLANG_TEST_STR"; then
      EXTRA_CXXFLAGS+=" -include-pch $PCH_FILE"
      # Define this only for clang, in gcc we still need the include directive.
      AC_DEFINE(PHP_ARMA_ENABLE_PCH, 1, [ Defined if using pre-compiled armadillo header. ])
    else
      EXTRA_CXXFLAGS+=' -I./build'
    fi
  fi

  # Disable some clang warnings we don't care.
  if test -n "$CLANG_TEST_STR"; then
    EXTRA_CXXFLAGS+=' -Wno-undefined-var-template -Wno-deprecated-declarations'
  fi

  # Enable/disable operator overloading support.
  OPERATORS_SRC="src/operators.cc"
  ARMA_SRC=`ls -1d src/*.cc | grep -v $OPERATORS_SRC`
  if test "$PHP_ARMA_OPERATORS" != "no"; then
    AC_DEFINE(PHP_ARMA_OPERATORS, 1, [ Defined if operator overloading is enabled for armadillo. ])
    ARMA_SRC+=" $OPERATORS_SRC"
  fi

  PHP_NEW_EXTENSION(arma, $ARMA_SRC, $ext_shared, , $EXTRA_CXXFLAGS)

  PHP_ADD_LIBRARY(armadillo, 1, ARMA_SHARED_LIBADD)
  PHP_SUBST(ARMA_SHARED_LIBADD)
fi