##### http://autoconf-archive.cryp.to/ax_boost_base.html
#
# SYNOPSIS
#
#   AX_BOOST_BASE([MINIMUM-VERSION])
#
# DESCRIPTION
#
#   Test for the Boost C++ libraries of a particular version (or newer)
#
#   If no path to the installed boost library is given the macro
#   searchs under /usr, /usr/local, /opt, and /opt/local, and evaluates the
#   $BOOST_ROOT environment variable. Further documentation is
#   available at <http://randspringer.de/boost/index.html>.
#
#   This macro calls:
#
#     AC_SUBST(BOOST_CPPFLAGS) / AC_SUBST(BOOST_LDFLAGS)
#
#   And sets:
#
#     HAVE_BOOST
#
# LAST MODIFICATION
#
#   2007-03-15
#
# COPYLEFT
#
#   Copyright (c) 2007 Thomas Porschberg <thomas@randspringer.de>
#
#   Copying and distribution of this file, with or without
#   modification, are permitted in any medium without royalty provided
#   the copyright notice and this notice are preserved.

AC_DEFUN([AX_BOOST_BASE],
[
AC_ARG_WITH([boost],
	AS_HELP_STRING([--with-boost@<:@=DIR@:>@], [use boost (default is yes) - it is possible to specify the root directory for boost (optional)]),
	[
    if test "$withval" = "no"; then
		want_boost="no"
    elif test "$withval" = "yes"; then
        want_boost="yes"
        ac_boost_path=""
    else
	    want_boost="yes"
        ac_boost_path="$withval"
	fi
    ],
    [want_boost="yes"])

if test "x$want_boost" = "xyes"; then
	boost_lib_version_req=ifelse([$1], ,1.20.0,$1)
	boost_lib_version_req_shorten=`expr $boost_lib_version_req : '\([[0-9]]*\.[[0-9]]*\)'`
	boost_lib_version_req_major=`expr $boost_lib_version_req : '\([[0-9]]*\)'`
	boost_lib_version_req_minor=`expr $boost_lib_version_req : '[[0-9]]*\.\([[0-9]]*\)'`
	boost_lib_version_req_sub_minor=`expr $boost_lib_version_req : '[[0-9]]*\.[[0-9]]*\.\([[0-9]]*\)'`
	if test "x$boost_lib_version_req_sub_minor" = "x" ; then
		boost_lib_version_req_sub_minor="0"
    	fi
	WANT_BOOST_VERSION=`expr $boost_lib_version_req_major \* 100000 \+  $boost_lib_version_req_minor \* 100 \+ $boost_lib_version_req_sub_minor`
	AC_MSG_CHECKING(for boostlib >= $boost_lib_version_req)
	succeeded=no

	dnl first we check the system location for boost libraries
	dnl this location ist chosen if boost libraries are installed with the --layout=system option
	dnl or if you install boost with RPM
	if test "$ac_boost_path" != ""; then
		BOOST_LDFLAGS="-L$ac_boost_path/lib"
		BOOST_CPPFLAGS="-I$ac_boost_path/include"
	else
		for ac_boost_path_tmp in /usr /usr/local /opt /opt/local ; do
			if test -d "$ac_boost_path_tmp/include/boost" && test -r "$ac_boost_path_tmp/include/boost"; then
				BOOST_LDFLAGS="-L$ac_boost_path_tmp/lib"
				BOOST_CPPFLAGS="-I$ac_boost_path_tmp/include"
				break;
			fi
		done
	fi

	CPPFLAGS_SAVED="$CPPFLAGS"
	CPPFLAGS="$CPPFLAGS $BOOST_CPPFLAGS"
	export CPPFLAGS

	LDFLAGS_SAVED="$LDFLAGS"
	LDFLAGS="$LDFLAGS $BOOST_LDFLAGS"
	export LDFLAGS

	AC_LANG_PUSH(C++)
     	AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
	@%:@include <boost/version.hpp>
	]], [[
	#if BOOST_VERSION >= $WANT_BOOST_VERSION
	// Everything is okay
	#else
	#  error Boost version is too old
	#endif
	]])],[
        AC_MSG_RESULT(yes)
	succeeded=yes
	found_system=yes
       	],[
       	])
	AC_LANG_POP([C++])



	dnl if we found no boost with system layout we search for boost libraries
	dnl built and installed without the --layout=system option or for a staged(not installed) version
	if test "x$succeeded" != "xyes"; then
		_version=0
		if test "$ac_boost_path" != ""; then
               		BOOST_LDFLAGS="-L$ac_boost_path/lib"
			if test -d "$ac_boost_path" && test -r "$ac_boost_path"; then
				for i in `ls -d $ac_boost_path/include/boost-* 2>/dev/null`; do
					_version_tmp=`echo $i | sed "s#$ac_boost_path##" | sed 's/\/include\/boost-//' | sed 's/_/./'`
					V_CHECK=`expr $_version_tmp \> $_version`
					if test "$V_CHECK" = "1" ; then
						_version=$_version_tmp
					fi
					VERSION_UNDERSCORE=`echo $_version | sed 's/\./_/'`
					BOOST_CPPFLAGS="-I$ac_boost_path/include/boost-$VERSION_UNDERSCORE"
				done
			fi
		else
			for ac_boost_path in /usr /usr/local /opt /opt/local ; do
				if test -d "$ac_boost_path" && test -r "$ac_boost_path"; then
					for i in `ls -d $ac_boost_path/include/boost-* 2>/dev/null`; do
						_version_tmp=`echo $i | sed "s#$ac_boost_path##" | sed 's/\/include\/boost-//' | sed 's/_/./'`
						V_CHECK=`expr $_version_tmp \> $_version`
						if test "$V_CHECK" = "1" ; then
							_version=$_version_tmp
	               					best_path=$ac_boost_path
						fi
					done
				fi
			done

			VERSION_UNDERSCORE=`echo $_version | sed 's/\./_/'`
			BOOST_CPPFLAGS="-I$best_path/include/boost-$VERSION_UNDERSCORE"
			BOOST_LDFLAGS="-L$best_path/lib"

	    		if test "x$BOOST_ROOT" != "x"; then
				if test -d "$BOOST_ROOT" && test -r "$BOOST_ROOT" && test -d "$BOOST_ROOT/stage/lib" && test -r "$BOOST_ROOT/stage/lib"; then
					version_dir=`expr //$BOOST_ROOT : '.*/\(.*\)'`
					stage_version=`echo $version_dir | sed 's/boost_//' | sed 's/_/./g'`
			        	stage_version_shorten=`expr $stage_version : '\([[0-9]]*\.[[0-9]]*\)'`
					V_CHECK=`expr $stage_version_shorten \>\= $_version`
				        if test "$V_CHECK" = "1" ; then
						AC_MSG_NOTICE(We will use a staged boost library from $BOOST_ROOT)
						BOOST_CPPFLAGS="-I$BOOST_ROOT"
						BOOST_LDFLAGS="-L$BOOST_ROOT/stage/lib"
					fi
				fi
	    		fi
		fi

		CPPFLAGS="$CPPFLAGS $BOOST_CPPFLAGS"
		export CPPFLAGS
		LDFLAGS="$LDFLAGS $BOOST_LDFLAGS"
		export LDFLAGS

		AC_LANG_PUSH(C++)
	     	AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
		@%:@include <boost/version.hpp>
		]], [[
		#if BOOST_VERSION >= $WANT_BOOST_VERSION
		// Everything is okay
		#else
		#  error Boost version is too old
		#endif
		]])],[
        	AC_MSG_RESULT(yes)
		succeeded=yes
		found_system=yes
       		],[
	       	])
		AC_LANG_POP([C++])
	fi

	if test "$succeeded" != "yes" ; then
		if test "$_version" = "0" ; then
			AC_MSG_ERROR([[We could not detect the boost libraries (version $boost_lib_version_req_shorten or higher). If you have a staged boost library (still not installed) please specify \$BOOST_ROOT in your environment and do not give a PATH to --with-boost option.  If you are sure you have boost installed, then check your version number looking in <boost/version.hpp>. See http://randspringer.de/boost for more documentation.]])
		else
			AC_MSG_NOTICE([Your boost libraries seems to old (version $_version).])
		fi
	else
		AC_SUBST(BOOST_CPPFLAGS)
		AC_SUBST(BOOST_LDFLAGS)
		AC_DEFINE(HAVE_BOOST,,[define if the Boost library is available])
	fi

        CPPFLAGS="$CPPFLAGS_SAVED"
       	LDFLAGS="$LDFLAGS_SAVED"
fi

])
