#!/bin/sh
# find rpm provides and requires for Haskell GHC libraries

# To use add the following lines to spec file:
#   %define _use_internal_dependency_generator 0
#   %define __find_requires /usr/lib/rpm/ghc-deps.sh --requires %{buildroot}%{ghclibdir}
#   %define __find_provides /usr/lib/rpm/ghc-deps.sh --provides %{buildroot}%{ghclibdir}

[ $# -ne 2 ] && echo "Usage: `basename $0` [--provides|--requires] %{buildroot}%{ghclibdir}" && exit 1

#set -x

MODE=$1
PKGBASEDIR=$2
PKGCONFDIR=$PKGBASEDIR/package.conf.d
GHC_VER=$(basename $PKGBASEDIR | sed -e s/ghc-//)

if [ ! -x "/usr/bin/ghc-pkg-${GHC_VER}" -a -x "$PKGBASEDIR/ghc-pkg" ]; then
    GHC_PKG="$PKGBASEDIR/ghc-pkg --global-package-db=$PKGCONFDIR"
else
    GHC_PKG="/usr/bin/ghc-pkg"
fi

case $MODE in
    --provides) FIELD=id ;;
    --requires) FIELD=depends ;;
    *) echo "`basename $0`: Need --provides or --requires" ; exit 1
esac

if [ -d "$PKGBASEDIR" ]; then
  SHARED=$(find $PKGBASEDIR -type f -name '*.so')
fi

files=$(cat)

for i in $files; do
    LIB_FILE=$(echo $i | grep /libHS | egrep -v "/libHSrts")
    if [ "$LIB_FILE" ]; then
	if [ -d "$PKGCONFDIR" ]; then
	    META=""
	    SELF=""
	    case $LIB_FILE in
		*.so) META=ghc ;;
		*.a) META=ghc-devel
		    if [ "$SHARED" ]; then
			SELF=ghc
		    fi
		    ;;
	    esac
	    if [ "$META" ]; then
		PKGVER=$(echo $LIB_FILE | sed -e "s%$PKGBASEDIR/\([^/]\+\)/libHS.*%\1%")
		HASHS=$(${GHC_PKG} -f $PKGCONFDIR field $PKGVER $FIELD | sed -e "s/^$FIELD: \+//")
		for i in $HASHS; do
		    case $i in
			*-*) echo "$META($i)" ;;
			*) ;;
		    esac
		done
		if [ "$MODE" = "--requires" -a "$SELF" ]; then
		    HASHS=$(${GHC_PKG} -f $PKGCONFDIR field $PKGVER id | sed -e "s/^id: \+//")
		    for i in $HASHS; do
			echo "$SELF($i)"
		    done
		fi
	    fi
	fi
    elif [ "$MODE" = "--requires" ]; then
	if file $i | grep -q 'executable, .* dynamically linked'; then
	    BIN_DEPS=$(objdump -p $i | grep NEEDED | grep libHS | grep -v libHSrts | sed -e "s%^ *NEEDED *libHS\(.*\)-ghc${GHC_VER}.so%\1%")
	    if [ -d "$PKGCONFDIR" ]; then
		PACKAGE_CONF_OPT="--package-conf=$PKGCONFDIR"
	    fi
	    for p in ${BIN_DEPS}; do
		HASH=$(${GHC_PKG} --global $PACKAGE_CONF_OPT field $p id | sed -e "s/^id: \+//" | uniq)
		echo "ghc($HASH)"
	    done
	fi
    fi
done

echo $files | tr [:blank:] '\n' | /usr/lib/rpm/rpmdeps $MODE