dnl AX_CHECK_HEADER_LIB([HEADER-NAME], [LIBRARY-NAME], [FUNCTION-IN-LIB], [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND], [LIB-WEB-PAGE])
AC_DEFUN([AX_CHECK_HEADER_LIB], [
    _header_check=""
    _lib_check=""

    AC_CHECK_HEADER([$1], [_header_check="yes"], [_header_check="no"])
    AC_CHECK_LIB([$2], [$3], [_lib_check="yes"], [_lib_check="no"])
    if [test "x$_header_check" = "xyes" && test "x$_lib_check" = "xyes"] ; then
         LIBS="$LIBS -l$2"
	 $4
    else
         echo "no Support for $2"
	 $5
    fi
])



dnl AX_CHECK_REQUIRED_HEADER_LIB([HEADER-NAME], [LIBRARY-NAME], [FUNCTION-IN-LIB], [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND], [LIB-WEB-PAGE], [CFLAGS], [OTHER_LIBS])
AC_DEFUN([AX_CHECK_REQUIRED_HEADER_LIB], [
    _header_check=""
    _lib_check=""
    LAST_FOUND_LIB=""

    _lib_USED=""
    _header_USED=""

    for _header in $1
    do
      AC_CHECK_HEADER([${_header}], [_header_check="yes" ; _header_USED=${_header}], [_header_check="no"], $7)
      if  test "x${_header_check}" = "xyes" ; then
        break
      fi
    done
    for _check_library in $2
    do
      AC_CHECK_LIB([${_check_library}], [$3], [_lib_check="yes"; _lib_USED=${_check_library}], [_lib_check="no"], $8)
      if test "x${_lib_check}" = "xyes" ; then
        LAST_FOUND_LIB=${_lib_USED}
	break
      fi
    done
    if [test "x${_header_check}" = "xyes" && test "x${_lib_check}" = "xyes"] ; then
	m4_ifval([$4], [$4], [
         LIBS="${LIBS} -l${_lib_USED}"])
    else
	m4_ifval([$5], [$5], [
         echo "------------------"
         echo "LIBRARY $2 not found."
         echo "please install the $2-LIBRARY-package which can be found at $6"
         echo "------------------"
	 exit -1])
    fi
])




dnl AX_CHECK_LUA([LUA_DIR])
AC_DEFUN([AX_CHECK_LUA], [
#dnl checking for LUA.
LUA_LIBS=
dnl Check for Lua.

LUA_INCLUDE_DIRECTORY="/usr/include"
LUA_COMMON_INCLUDE_DIRECTORIES="
      `ls -dr $1                       2>/dev/null`
      /usr/include
      `ls -dr /usr/include/lua*        2>/dev/null`
      `ls -dr /usr/lib/lua/include     2>/dev/null`
      `ls -dr /usr/local/include/lua   2>/dev/null`
      `ls -dr /opt/lua*/include        2>/dev/null`
      `ls -dr /Developer/lua*/include  2>/dev/null`
    "

  for _lua_include_directory in ${LUA_COMMON_INCLUDE_DIRECTORIES}
    do
      if test -e ${_lua_include_directory}/lua.h ; then
        LUA_INCLUDE_DIRECTORY=${_lua_include_directory}
	CPPFLAGS="${CPPFLAGS} -I${LUA_INCLUDE_DIRECTORY}"
        break
      fi
  done
    if test -n ${LUA_INCLUDE_DIRECTORY} ; then
      echo "Lua-Include Directory is: ${LUA_INCLUDE_DIRECTORY}"
    else
      AC_MSG_ERROR([Lua Headers not found])
    fi


AC_CHECK_LIB([dl], [dlopen])
AX_CHECK_REQUIRED_HEADER_LIB([lua.h], [lua lua50], [lua_open],
dnl libLUA found
     [LUA_LIBS="${LUA_LIBS} -l${LAST_FOUND_LIB}"  AX_CHECK_REQUIRED_HEADER_LIB([lualib.h], [lualib lualib50], [luaopen_base], 
dnl liblualib found
      [LUA_LIBS="${LUA_LIBS} -l${LAST_FOUND_LIB}"],,
      [http://www.lua.org],, [${LUA_LIBS} -ldl -lm])],
dnl liblua not found (download it)
       [AX_GET_INSTALL_NECESSARY_LIB([http://www.lua.org/ftp], [lua-5.0.tar.gz], [lua-5.0], [lib/lua], [include/*.h lib/*.a])
       LUA_LIBS="lib/lua/liblualib.a lib/lua/liblua.a"  CPPFLAGS="${CPPFLAGS} -Ilib/lua" ], [http://www.lua.org])


AC_SUBST([LUA_LIBS])
])





dnl AX_GET_INSTALL_NECESSARY_LIB([FTP-DIR], [DIST-FILE], [DIST-DIR], [INSTALL-DIR], [INSTALL-FILES], [CONFIG-FLAGS], [MAKE-OPTS])
AC_DEFUN([AX_GET_INSTALL_NECESSARY_LIB], [

   _get_install_FTP=$1
   _get_install_DISTFILE=$2
   _get_install_DISTDIR=$3
   _get_install_INSTALLDIR=$4
   dnl $5 is left out (inegrated bellow)
   _get_install_CONFIGFLAGS=$6
   _get_install_MAKEOPTS=$7

dnl DOWNLOADING THE FILE
   if test -f "${_get_install_DISTFILE}" ; then
     echo "${_get_install_DISTFILE} already downloaded"
   else
     echo "Getting ${_get_install_DISTFILE} from ${_get_install_FTP}/${_get_install_DISTFILE}"
     echo `wget ${_get_install_FTP}/${_get_install_DISTFILE}`
   fi

dnl UNCOMPRESS STAGE
   echo "Uncompressing ${_get_install_DISTFILE}"
   echo `tar xzvf ${_get_install_DISTFILE}`

dnl ENTER DIRECTORY AND EXECUTE CONFIGURE AND MAKE
   _get_install_PWD=`pwd`
   cd ${_get_install_DISTDIR}
dnl configure
   if test -x "configure" ; then
    ./configure ${_get_install_CONFIGFLAGS}
   fi
   make ${_get_install_MAKEOPTS}
   cd ${_get_install_PWD}

dnl INSTALL STAGE
   echo "Installing Libraries and Headers into ${_get_install_INSTALLDIR} local directory"
  
   mkdir -p ${_get_install_INSTALLDIR}
   for _get_install_installfile in $5
    do
     echo "copy  ${_get_install_DISTDIR}/${_get_install_installfile} to ${_get_install_INSTALLDIR}/"
     cp `ls -dr ${_get_install_DISTDIR}/${_get_install_installfile}` "${_get_install_INSTALLDIR}/"
    done

#cleaning up
  echo "rm -rf ${_get_install_DISTDIR}"
  rm -rf ${_get_install_DISTDIR}
  echo "rm ${_get_install_DISTFILE}"
  rm ${_get_install_DISTFILE}
])