#!/bin/sh

set -e

if test "x$1" = "x--debug"; then
  DEBUG=yes
fi

if test "x$DEBUG" = "xyes"; then
  set -x
  set -v
fi

###############################################

#
# Configuration
#

# name of the "control" files
CONTROL="dune.module"

###############################################

#
# LIB
#

parse_control() {
  if test -f "$1"; then
	export module=$(echo $(grep Module: "$1" | cut -d ':' -f2))
    deps=$(echo $(grep Depends: "$1" | cut -d ':' -f2))
    sugs=$(echo $(grep Suggests: "$1" | cut -d ':' -f2))
	path=$(dirname "$1")
    if test "x$module" != "x"; then
      export HAVE_${module}=yes
	  export PATH_${module}="$path"
	  export DEPS_${module}="$deps"
	  export SUGS_${module}="$sugs"
    fi
  else
	echo "ERROR: could not read file $1"
	false
  fi
}

find_modules() {
  if test -d "$1"; then
    dir=$(cd "$1" && pwd)
	while read m; do
	  if test "x$m" != "x"; then
		export module=""
		parse_control "$m"
        export MODULES="$MODULES $module"
      fi
	done <<EOF
 $(find "$dir" -name $CONTROL )
EOF
  else
	echo "ERROR: could not find directory $1"
	false
  fi
}

#
# load the $CONTROL file, skip all control variables
# and run a command
#
# parameters:
# $1 command to execute
# $2 full path of the $CONTROL file
#
eval_control() {
  command=$1
  file=$2
  shift 2
  if test -f "$file"; then
	# open subshell
	(
      set -e
      # load functions defined in $file
	  # if $command is not defined in $file,
	  # then the default implementation will be executed
	  eval "$(grep -v -e '^[[:alnum:]]\+:' $file)"
	  # execute $command
      $command "$@"
    ) || false
  fi
}

_build_module() {
  command=$1
  module=$2
  shift 2
  if test "x$(eval echo \$BUILD_DONE_${command}_${module})" != "xyes"; then
    echo "--- building $module ---"
	# resolve dependencies
	for dep in $(eval "echo \$DEPS_$module"); do
      echo "--- $module depends on $dep ... calling ---"
      (set -e; _build_module $command $dep "$@") || false
    done
	# resolve suggestions
	for dep in $(eval "echo \$SUGS_$module"); do
      echo -n "--- $module suggests $dep ... "
      if test "x$(eval echo \$HAVE_$dep)" != "x"; then
		echo "calling ---"
        (set -e; _build_module $command $dep "$@") || false
	  else
		echo "skipping ---"
	  fi
    done
	# really build this module
	echo "--- calling $command for $module ---"
    export BUILD_DONE_${command}_${module}=yes
	path=$(eval "echo \$PATH_${module}")
	(
      set -e
      cd "$path"
	  eval_control $command $path/$CONTROL "$@"
    ) || exit 1
  else
    echo "--- skipping $module ---"
  fi
}

build_modules() {
  command=$1
  runcommand=run_$command
  shift
  load_opts $command
  for m in $MODULES; do
    _build_module $runcommand $m "$@"
  done
}

load_opts() {
  command=$1
  COMMAND=$(echo $command | tr '[:lower:]' '[:upper:]')
  if test "x$OPTS_FILE" != "x"; then
    echo "----- loading default flags \$${COMMAND}_FLAGS from $OPTS_FILE -----"
    CMD_PARAMS="$(. $OPTS_FILE; eval echo \$${COMMAND}_FLAGS)"
  fi
}

###############################################

#
# default implementations for commands... 
# these can be overwritten in the $CONTROL files
#

COMMANDS="autogen configure make all exec"

run_default_nothing () { echo -n; }

run_default_exec () { bash -c "eval $CMD_PARAMS"; }

run_default_update () { echo "WARNING: Doing nothing"; }

run_default_autogen () {
  PARAMS="$CMD_PARAMS"
  if test -x autogen.sh; then
	for m in $MODULES; do
	  path=$(eval "echo \$PATH_$m")
	  if test -d $path/m4; then
		ACLOCAL_FLAGS="$path $ACLOCAL_FLAGS"
	  fi
	done
	eval ./autogen.sh "$ACLOCAL_FLAGS" "$PARAMS" || exit 1
  fi
}

run_default_configure () {
  PARAMS="$CMD_PARAMS"
  if test -x configure; then
    if test "x$HAVE_dune_common" == "xyes"; then
      PARAMS="$PARAMS \"--with-dunecommon=$PATH_dune_common\""
    fi
    if test "x$HAVE_dune_grid" == "xyes"; then
      PARAMS="$PARAMS \"--with-dunegrid=$PATH_dune_grid\""
    fi
    if test "x$HAVE_dune_istl" == "xyes"; then
      PARAMS="$PARAMS \"--with-duneistl=$PATH_dune_istl\""
    fi
    if test "x$HAVE_dune_disc" == "xyes"; then
      PARAMS="$PARAMS \"--with-dunedisc=$PATH_dune_disc\""
    fi
	echo ./configure "$PARAMS"
	eval ./configure "$PARAMS" || exit 1
  else
    if test -f configure.in || test -f configure.ac; then
	  echo "ERROR: configure.[in|ac] found, but configure missing"
	  echo "did you forget to run autoconf?"
	  exit 1
	fi
  fi
}

run_default_make () {
  PARAMS="$CMD_PARAMS"
  echo make "$PARAMS"
  eval make "$PARAMS"
}

run_default_all () {
  load_opts autogen
  run_autogen "$@"
  load_opts configure
  run_configure "$@"
  load_opts make
  run_make "$@"
}

run_nothing () {
  run_default_nothing "$@"
}
run_exec () {
  run_default_exec "$@"
}
run_update () {
  run_default_update "$@"
}
run_autogen () {
  run_default_autogen "$@"
}
run_configure () {
  run_default_configure "$@"
}
run_make () {
  run_default_make "$@"
}
run_all () {
  run_default_all "$@"
}

###############################################

#
# main
#

onfailure() {
  echo Execution terminated due to errors!
  exit 1
}

usage () {
    echo "Usage: $0 [OPTIONS] COMMAND [COMMAND-OPTIONS]"
    echo ""
    echo "Execute COMMAND for all Dune modules."
    echo "Dependencies are controlled by the dune.module files."
    echo ""
	echo "Options:"
	echo "  -h, --help         show this help"
	echo "      --debug        enable debug output of this script"
	echo "      --opts=FILE    load default options from FILE (see dune-common/bin/example.opts)"
	echo "Commands:"
	echo "  \`help'"
	for i in $COMMANDS; do
      echo "  \`$i'"
    done
    echo
}

if test "x$1" == "x"; then
  usage
  exit 1
fi

trap onfailure EXIT

while test "x$1" != "x"; do
	# get option
	option=$1
	shift

	# get args
    set +e
    # stolen from configure...
    # when no option is set, this returns an error code
    arg=`expr "x$option" : 'x[^=]*=\(.*\)'`
    set -e

	# switch
    case "$option" in
	--opts=*)
	  if test "x$arg" == "x"; then
		usage
		echo "ERROR: Parameter for --opts is missing"
		echo
		exit 1;
	  fi
	  OPTS_FILE=$(cd $(dirname $arg); pwd)/$(basename $arg)
	  if ! test -r "$OPTS_FILE"; then
		usage
		echo "ERROR: could not read opts file \"$OPTS_FILE\""
		echo
		exit 1;
	  fi
	;;
	-h|--help) 
      command=help
	  break
    ;;
	--debug) true ;;
	*)
      command=$option
	  break
    ;;
    esac
done

while test "x$1" != "x"; do
  # setup paramter list
  CMD_PARAMS="$CMD_PARAMS \"$1\""
  shift
  # disable usage of opts file
  if test "x$OPTS_FILE" != "x"; then
	echo "WARNING: commandline parameters will overwrite setting in opts file \"$OPTS_FILE\""
  fi 
  OPTS_FILE=""
done

case "$command" in
  update | autogen | configure | make | all | exec | nothing)
    find_modules .
    build_modules $command "$@"
    ;;
  help)
	usage
	;;
  *)
    echo "ERROR: unknown command \"$command\""
	usage
    exit 1
	;;
esac

trap - EXIT

echo done