#!/bin/sh

set -e

# summary of how this script can be called:
#        * <new-preinst> `install'
#        * <new-preinst> `install' <old-version>
#        * <new-preinst> `upgrade' <old-version>
#        * <old-preinst> `abort-upgrade' <new-version>
#
# For details see /usr/share/doc/packaging-manual/

# usage: divert_libGL DIR [OLDFILE]
# if OLDFILE is not empty, fixes an old diversion
divert_libGL ()
{
    if [ "$2" ]; then
        # move our libGL out of the way for a while
        mv "$1/libGL.so.1.2" "$1/fglrx-libGL.so.1.2"

        # remove the old diversion
        dpkg-divert --remove --package fglrx-driver \
            --divert "$2" \
            --rename "$1/libGL.so.1.2"
    fi

    if [ ! -d "$1/fglrx/diversions" ]; then
        mkdir -p "$1/fglrx/diversions"
    fi

    # divert the real library first to make sure that a ldconfig run
    # between the two dpkg-divert calls doesn't recreate the link
    dpkg-divert --add --package fglrx-driver \
        --divert "$1/fglrx/diversions/libGL.so.1.2" \
        --rename "$1/libGL.so.1.2"
    dpkg-divert --add --package fglrx-driver \
        --divert "$1/fglrx/diversions/libGL.so.1" \
        --rename "$1/libGL.so.1"

    if [ "$2" ]; then
        # move our libGL back in its place
        mv "$1/fglrx-libGL.so.1.2" "$1/libGL.so.1.2"
    fi
}

case "$1" in
    install)
        divert_libGL /usr/X11R6/lib

        if [ "$(dpkg --print-architecture)" = "amd64" ]; then
            divert_libGL /emul/ia32-linux/usr/X11R6/lib
        fi
    ;;

    upgrade)
        if dpkg --compare-versions "$2" lt "8.20.8"; then
            # fix old diversion
            divert_libGL /usr/X11R6/lib \
                /usr/share/fglrx/diversions/libGL.so.1.2

            if [ "$(dpkg --print-architecture)" = "amd64" ]; then
                divert_libGL /emul/ia32-linux/usr/X11R6/lib \
                    /usr/share/fglrx/diversions/libGL.so.1.2_32bit
            fi

            rmdir /usr/share/fglrx/diversions || true
            rmdir /usr/share/fglrx            || true
        fi
    ;;

    abort-upgrade)
    ;;

    *)
        echo "preinst called with unknown argument \`$1'" >&2
        exit 0
    ;;
esac

#DEBHELPER#