#! /bin/sh
# $Id$
# checks for dune-headers and everything they need

# TODO
#
# - use pkg-config if --enable-localdune is not provided

#   #export PKG_CONFIG_LIBDIR=$with_dune/dune
#  #PKG_CHECK_MODULES(DUNE, dune)  

AC_DEFUN([DUNE_CHECK_MODULES],[
  AC_REQUIRE([AC_PROG_CXX])
  AC_REQUIRE([AC_PROG_CXXCPP])

  # ____DUNE_CHECK_MODULES_____ ($1)

  echo checking for $1

  AC_DEFUN([_dune_module], [$1])
  AC_DEFUN([_dune_header], [$2])
  AC_DEFUN([_dune_ldpath], [$3])
  AC_DEFUN([_dune_lib],    [$4])
  AC_DEFUN([_dune_symbol], [$5])
  AC_DEFUN([_DUNE_MODULE], [m4_toupper(_dune_module)])

  # switch tests to c++
  AC_LANG_PUSH([C++])

  # the usual option...
  AC_ARG_WITH([_dune_module],
    AC_HELP_STRING([--with-_dune_module=PATH],[_dune_module directory]))

  # backup of flags
  ac_save_CPPFLAGS="$CPPFLAGS"
  ac_save_LIBS="$LIBS"
  CPPFLAGS=""
  LIBS=""

  # is a directory set?
  if test x$withval != x ; then
    # expand tilde
    if test -d $withval ; then
      # expand tilde / other stuff
      _DUNE_MODULE[]ROOT=`cd $withval && pwd`

      # expand search path (otherwise empty CPPFLAGS)
      _DUNE_MODULE[]_CPPFLAGS="-I$_DUNE_MODULE[]ROOT"
    else
      AC_MSG_ERROR([_dune_module-directory $withval does not exist])
    fi
  fi

  CPPFLAGS="$DUNE_CPPFLAGS $_DUNE_MODULE[]_CPPFLAGS"
  # test for an arbitrary header
  AC_CHECK_HEADER([dune/[]_dune_header],
    [HAVE_[]_DUNE_MODULE=1
     _DUNE_MODULE[]_CPPFLAGS="$CPPFLAGS"],
    [HAVE_[]_DUNE_MODULE=0
     _DUNE_MODULE[]_CPPFLAGS=""
     AC_MSG_ERROR([$withval does not seem to contain a valid _dune_module (dune/[]_dune_header not found)])]
  )

  ## check for lib (if lib name was provided)
  ifelse(_dune_lib,,[echo _dune_module does not provide libs],[
    # did we find the headers?
    if test x$HAVE_[]_DUNE_MODULE = x1 ; then
      ac_save_LDFLAGS="$LDFLAGS"
      ac_save_LIBS="$LIBS"
      HAVE[]_DUNE_MODULE=0

      ## special test for a local installation
      if test x$_DUNE_MODULE[]ROOT != x ; then
        # have a look into the dune module directory
        LDFLAGS="$LDFLAGS -L$_DUNE_MODULE[]ROOT/dune/_dune_ldpath"

        # only check for a .la-file
        if test -s $_DUNE_MODULE[]ROOT/_dune_ldpath/lib[]_dune_lib[].la ; then
            _DUNE_MODULE[]_LDFLAGS="-L$_DUNE_MODULE[]ROOT/_dune_ldpath"
            echo found lib[]_dune_lib.la, setting LDFLAGS to $_DUNE_MODULE[]_LDFLAGS

            # provide arguments like normal lib-check
            _DUNE_MODULE[]_LIBS="-l[]_dune_lib"
            HAVE_[]_DUNE_MODULE=1
        else
            AC_MSG_ERROR([$withval does not seem to contain a valid _dune_module (lib[]_dune_lib[].la not found)])
        fi
      fi

      ## normal test for a systemwide install
      if test x$HAVE_[]_DUNE_MODULE = x0 ; then
         # !!! should be pkg-config later (which would save the special
         # header-check as well)

         # Beware! Untested!!!
         LIBS="-l[]_dune_lib"
         AC_TRY_LINK(,_dune_symbol,
              [HAVE_[]_DUNE_MODULE=1
               _DUNE_MODULE[]_LIBS="$LIBS"],
              [HAVE_[]_DUNE_MODULE=0
               AC_MSG_ERROR([failed to link with lib[]_dune_lib[].la])]
          )
      fi

      if test x$_DUNE_MODULE[]_LIBS = x; then
        AC_MSG_ERROR([failed to find lib[]_dune_lib[] needed of module _dune_module])
      fi

      # reset variables
      LDFLAGS="$ac_save_LDFLAGS"
      LIBS="$ac_save_LIBS"
    fi
  ])

  # did we succeed?
  if test x$HAVE_[]_DUNE_MODULE = x1 ; then
    # set variables for our modules
    AC_SUBST(_DUNE_MODULE[]_CPPFLAGS, "$_DUNE_MODULE[]_CPPFLAGS")
    AC_SUBST(_DUNE_MODULE[]_LDFLAGS, "$_DUNE_MODULE[]_LDFLAGS")
    AC_SUBST(_DUNE_MODULE[]_LIBS, "$_DUNE_MODULE[]_LIBS")
    AC_SUBST(_DUNE_MODULE[]ROOT, "$_DUNE_MODULE[]ROOT")
    AC_DEFINE(HAVE_[]_DUNE_MODULE, 1, [Define to 1 if _dune_module was found])

    # set DUNE_* variables
    AC_SUBST(DUNE_CPPFLAGS, "$DUNE_CPPFLAGS $_DUNE_MODULE[]_CPPFLAGS")
    AC_SUBST(DUNE_LDFLAGS, "$DUNE_LDFLAGS $_DUNE_MODULE[]_LDFLAGS")
    AC_SUBST(DUNE_LIBS, "$DUNE_LIBS $_DUNE_MODULE[]_LIBS")
	
    # add to global list
    DUNE_PKG_CPPFLAGS="$DUNE_PKG_CPPFLAGS $DUNE_CPPFLAGS"
    DUNE_PKG_LIBS="$DUNE_PKG_LIBS $LIBS"
    DUNE_PKG_LDFLAGS="$DUNE_PKG_LDFLAGS $DUNE_LDFLAGS"
  else
    AC_MSG_ERROR([could not find required module _dune_module])
  fi

  # reset previous flags
  CPPFLAGS="$ac_save_CPPFLAGS"
  LIBS="$ac_save_LIBS"

  # restore previous language settings (leave C++)
  AC_LANG_POP([C++])
])

AC_DEFUN([DUNE_CHECK_DISPATCH],[
  ifelse([$1], [], [],
         [$1], [dunecommon],[
           DUNE_CHECK_MODULES([dunecommon], [common/stdstreams.hh], [common], [common], [Dune::derr.active();])],
         [$1], [dunegrid],[
           DUNE_CHECK_MODULES([dunegrid], [grid/common/grid.hh], [grid], [grid], [Dune::PartitionName])],
         [$1], [duneistl],[
           DUNE_CHECK_MODULES([duneistl], [istl/allocator.hh],,,)],
         [$1], [dunedisc],[
           DUNE_CHECK_MODULES([dunedisc], [disc/functions/functions.hh], [disc], [disc], [Dune::LagrangeShapeFunctions<double, double, 3>::general])],
         [AC_MSG_ERROR([Unknown module $1])])
])

AC_DEFUN([DUNE_DEV_MODE],[
  AC_ARG_ENABLE(dunedevel,
    AC_HELP_STRING([--enable-dunedevel],[activate Dune-Developer-mode]))

  if test x"$enable_dunedevel" = xyes ; then
    AC_DEFINE(DUNE_DEVEL_MODE, 1, [Activates developer output])
  fi
])

AC_DEFUN([DUNE_MODULE_DEPENDENCIES],[
  ifelse($#, 0, , $#, 1, [DUNE_CHECK_DISPATCH($1)], [DUNE_CHECK_DISPATCH($1) DUNE_MODULE_DEPENDENCIES(m4_shift($@))])
])

AC_DEFUN([DUNE_SYMLINK],[
  # create symlink for consistent paths even when $(top_srcdir) is not
  # called dune/ (if filesystem/OS supports symlinks)
  AC_PROG_LN_S
  if test x"$LN_S" = x"ln -s" ; then
    # Symlinks possible!
 
    # Note: we are currently in the build directory which may be != the
    # source directory
 
    # does a file already exist?
    if test -e dune ; then
      # exists: is a symlink?
      if test -L dune ; then
        if ! test -r dune/$ac_unique_file ; then
          AC_MSG_ERROR([Symlink 'dune' exists but appears to be wrong! Please remove it manually])
        fi
      fi
    else
      echo Creating dune-symlink...
      # set symlink in build directory to sources
      ln -s $srcdir dune

      # sanity check
      if ! test -r dune/$ac_unique_file ; then
        AC_MSG_ERROR([Sanity check for symlink failed! Please send a bugreport to dune@hal.iwr.uni-heidelberg.de])
      fi
    fi 
  else
    # no symlinks possible... check name of directory
    AC_MSG_ERROR([No symlinks supported! You have to install dune. No inplace usage possible!])
  fi
])