#!/bin/sh
#
# Copyright 1994 Patrick Volkerding, Moorhead, Minnesota USA
# All rights reserved.
#
# Redistribution and use of this script, with or without modification, is 
# permitted provided that the following conditions are met:
#
# 1. Redistributions of this script must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
#
#  THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
#  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
#  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
#  EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
#  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
#  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
#  OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 
#  WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 
#  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 
#  ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#

TARGET_DIR=/
TMP=/tmp
ADM_DIR=$TARGET_DIR/var/log

keep_files() {
 while read FILE ; do
  if [ -r "$TARGET_DIR/$FILE" -a ! -d "$TARGET_DIR/$FILE" ]; then
    echo "  --> $FILE was found in another package. Skipping."
  fi
 done
}

keep_links() {
 while read LINK ; do
  echo "Duplicate link. Not executing: $LINK"
 done
}

delete_files() {
 while read FILE ; do
  if [ -r "$TARGET_DIR/$FILE" -a ! -d "$TARGET_DIR/$FILE" ]; then
    if [ ! "$WARN" = "true" ]; then
     echo "  --> Deleting $FILE"
     rm -f $TARGET_DIR/$FILE
    else
     echo "  --> $FILE would be deleted"
    fi
  fi
 done
}

delete_links() {
 while read LINK ; do
  if [ ! "$WARN" = "true" ]; then
   echo "Unique link. Executing: $LINK"
  else
   echo "Unique link. Would execute: $LINK"
  fi
 done
}

# Conversion to 'comm' utility by Mark Wisdom.
# is pretty nifty! :^)
remove_packages() {
 for package_name in $* 
 do
  echo
  if [ -r $ADM_DIR/packages/$package_name ]; then
   if [ ! "$WARN" = true ]; then
    echo "Removing package $package_name..."
   fi
   if fgrep "./" $ADM_DIR/packages/$package_name 1> /dev/null 2>&1; then
    TRIGGER=".\/"
   else
    TRIGGER="FILE LIST:"
   fi
   if [ ! "$WARN" = true ]; then
    echo "Removing files:"
   fi
   sed -n "/$TRIGGER/,/^$/p" < $ADM_DIR/packages/$package_name | sort -u > $TMP/delete_list
   # Pat's new-new && improved pre-removal routine.
   for DIR in $ADM_DIR/removed_packages $ADM_DIR/removed_scripts ; do
    if [ ! -d $DIR ] ; then mkdir -p $DIR ; chmod 755 $DIR ; fi
   done
   if [ "$WARN" = "true" ]; then
    mv $ADM_DIR/packages/$package_name $TMP/$package_name 1> /dev/null 2>&1
   else
    mv $ADM_DIR/packages/$package_name $ADM_DIR/removed_packages 1> /dev/null 2>&1
   fi
   if [ -r $ADM_DIR/scripts/$package_name ]; then
    cat $ADM_DIR/scripts/$package_name | fgrep 'rm -rf' | sort -u > $TMP/del_link_list
    if [ "$WARN" = "true" ]; then
     mv $ADM_DIR/scripts/$package_name $TMP/$package_name.script
    else
     mv $ADM_DIR/scripts/$package_name $ADM_DIR/removed_scripts 1> /dev/null 2>&1
    fi
    cat $ADM_DIR/scripts/* | fgrep 'rm -rf' | sort -u > $TMP/required_links
    comm -12 $TMP/del_link_list $TMP/required_links | keep_links
    comm -23 $TMP/del_link_list $TMP/required_links | delete_links
    comm -23 $TMP/del_link_list $TMP/required_links > $TMP/delscript
    if [ ! "$WARN" = "true" ]; then
     ( cd $TARGET_DIR ; sh $TMP/delscript )
    fi
    rm -f $TMP/del_link_list $TMP/required_links $TMP/delscript
   fi
   cat $ADM_DIR/packages/* | sort -u > $TMP/required_files
   comm -12 $TMP/delete_list $TMP/required_files | keep_files
   comm -23 $TMP/delete_list $TMP/required_files | delete_files
   rm -f $TMP/delete_list $TMP/required_files
   if [ "$WARN" = "true" ]; then
    mv $TMP/$package_name $ADM_DIR/packages/$package_name
    if [ -r $TMP/$package_name.script ]; then
     mv $TMP/$package_name.script $ADM_DIR/scripts/$package_name
    fi
   fi
  else
   echo "No such package: $package_name. Can't remove."
  fi
 done
}

if [ "$1" = "-warn" ]; then
 echo "Only warning... not actually removing any files."
 echo "Here's what would be removed (and left behind) if you"
 echo "removed the package(s):"
 echo
 WARN=true
 shift 1
fi

remove_packages $*