#!/bin/sh -e

. /usr/share/debconf/confmodule

NAME=apt-cacher-ng
CONFIGFILE=/etc/$NAME/zz_debconf.conf
LDIR=/var/log/$NAME 
SLIST=/etc/apt/sources.list
CFG=/etc/apt-cacher-ng
DDIR=/usr/lib/apt-cacher-ng
VDIR=/var/lib/apt-cacher-ng
udefault=$VDIR/backends_ubuntu.default
ddefault=$VDIR/backends_debian.default
BINPATH=/usr/sbin/$NAME
TOOL=$DDIR/acngtool

gen_mirror_list_from_sources_list() {

   tmpfile="$1.dpkg-new"

   case "$2" in
      *gz)
      pickcmd=zgrep
      ;;
      *)
      pickcmd=grep
      ;;
   esac;

   (
   grep -h '^deb'  $SLIST.d/* $SLIST 2>/dev/null | sed -e "s,ftp:/,http:/," | \
   (
   while read a b c ; do
      case "$b" in http*) $pickcmd "$b" "$2" || true ;; esac
   done
   ) # but don't add duplicates
   ) | ( while read a ; do grep -q "$a" "$tmpfile" 2>/dev/null || echo "$a" >> "$tmpfile" ; done)

   # replace only if it got contents
   if test -s "$tmpfile" ; then
      cat "$tmpfile" > "$1"
   fi

   rm -f "$tmpfile"

}

sig='#09f369bf9c82a2210934e82213360226'

def_file_header="# This is a configuration file. All lines starting with # will be ignored.
#
# WARNING: this file is maintained by configuration scripts of the apt-cacher-ng
# package. All manual changes WILL BE LOST after the next package upgrade as
# long as a line looking exactly like $sig
# is found inside. Remove or modify that line to stop auto-updates of this file.
$sig

"

# .default files specify a set of fallback configuration for the cases where
# it's not possible to construct something useful in the regular backends files

set_def_files() {

   # if not readable or still has the signature
   if ! test -r $ddefault  || grep -q "^[[:space:]]*$sig[[:space:]]*$" $ddefault ; then
      echo "$def_file_header" > $ddefault
      # ftp.debian.org is a geodns mapped location, should be good as-is
      echo http://ftp.debian.org/debian/ >> $ddefault
   fi

   if ! test -r $udefault || grep -q "^[[:space:]]*$sig[[:space:]]*$" $udefault ; then

      guess_ubuntu_mirrors

      # silent fix of the broken file generated by the first versions of the mirror picking code
      if grep -q "^http://archive.ubuntu.com/?$" $udefault ; then
         sed "s,http://archive.ubuntu.com,http://archive.ubuntu.com/ubuntu," -i $udefault
      fi
   fi
}

get_umirrors_txt() {
   # mirror suggestions from Ubuntu's service might be a good candidate
   if ! $check_sane_data ; then
      mirurl=http://mirrors.ubuntu.com/mirrors.txt
      if which wget > /dev/null 2>&1 ; then
         timeout 15 wget --timeout=10 -q -O- $mirurl >> $tmpfile 2>/dev/null || true
      elif which curl > /dev/null 2>&1 ; then
         timeout 15 curl -m 10 --fail -s $mirurl >> $tmpfile 2>/dev/null || true
      else
         timeout 15 $TOOL NetworkTimeout=10 curl $mirurl $BINPATH >> $tmpfile 2>/dev/null || true
      fi
   fi
}

guess_ubuntu_mirrors() {
   
   tmpfile="`mktemp`"

   if [ ! "$http_proxy" ] ; then
      prx=$(apt-config dump | grep Acquire::http::Proxy | cut -f2 -d'"') || true
      if [ "$prx" ] ; then
         http_proxy="$prx"
         export http_proxy
      fi
   fi

   check_sane_data="grep -q http:// $tmpfile"

   # may hit a local mirror which also hosts Debian, use it then
   sed -e 's,\([a-z]\)/.*,\1,' < $CFG/backends_debian | xargs -I{} grep "{}" $DDIR/ubuntu_mirrors > $tmpfile || true

   get_umirrors_txt

   # maybe try without a proxy too, in case the proxy entry points at a broken apt-cacher-ng
   if ! $check_sane_data && test "$http_proxy" ; then
           unset http_proxy
           get_umirrors_txt
   fi

   # still nothing. Sneak more information from Debian backend configuration?
   if ! $check_sane_data ; then # ok, go by Debian TLD
      grep debian.org/ /etc/apt-cacher-ng/backends_debian | \
         sed -e 's,^http://ftp[2-3]\?\.\([a-z][a-z]\).*,http://\1.archive.ubuntu.com/,' | \
         sort -u | xargs -I{} grep "{}" $DDIR/ubuntu_mirrors > $tmpfile || true
   fi

   if ! $check_sane_data ; then # ok, then try just any TLD
      sed -e 's,^http://\([^\/]\+\).*,\1,;s,.*\.\(.*\),http://\1.archive.ubuntu.com/,' < $CFG/backends_debian | \
         sort -u | xargs -I{} grep "{}" $DDIR/ubuntu_mirrors > $tmpfile || true
   fi

   if ! $check_sane_data ; then
      echo http://archive.ubuntu.com/ubuntu/ > $tmpfile || true
   fi

   if $check_sane_data ; then
      echo "$def_file_header" > $udefault
      cat $tmpfile >> $udefault
   fi

   rm -f "$tmpfile" 2>/dev/null

}

gen_lists() {
   gen_mirror_list_from_sources_list $CFG/backends_debian $DDIR/deb_mirrors.gz
   gen_mirror_list_from_sources_list $CFG/backends_ubuntu $DDIR/ubuntu_mirrors
   gen_mirror_list_from_sources_list $CFG/backends_debvol $DDIR/debvol_mirrors.gz
}

if [ "$1" = "configure" ]; then

   db_get $NAME/cachedir
   case "$RET" in
      keep|"")
         # maybe never displayed to user
         CDIRCONF='# CacheDir set to "keep", not overriding here'
         ;;
      *)
         # ok, configured by debconf, will be created as needed
         CDIR="$RET"
         CDIRCONF="CacheDir: $RET"
         ;;
   esac

   if test -z "$CDIR" ; then
      CDIR=$($TOOL printvar CacheDir -c $CFG 2>/dev/null)
      if test -z "$CDIR" ; then
         # unlikely... but even if PEBCAK, prepare the correct folder now
         CDIR=/var/cache/$NAME
      fi
   fi

   # user should exist. adduser sometimes fails (system range issue) but that's ok
   adduser --quiet --system --group --no-create-home --home "$CDIR" $NAME || id $NAME
   # also setup permissions ASAP
   if [ -z "$(dpkg-statoverride --list $CFG/security.conf)" ] ; then
      dpkg-statoverride --update --add root $NAME 640 $CFG/security.conf
   fi

   for x in "$CDIR" $LDIR ; do 
      if [ ! -d "$x" ]; then
         install -d -g $NAME -o $NAME -m2755 "$x"
      fi
   done

   # creating some stubs
   # least invasive cooperation with the old style behavior for now
   for cfn in backends_debvol backends_ubuntu backends_debian ; do
      if ! test -e $CFG/$cfn ; then
         if test -e $CFG/oldconffiles/$cfn ; then
            mv -f $CFG/oldconffiles/$cfn $CFG/$cfn
         else
            install -m644 /dev/null $CFG/$cfn
         fi
      fi
   done
   rm -rf $CFG/oldconffiles

   db_get apt-cacher-ng/gentargetmode || true

   case "$RET" in
      "Create once"|"Set up once")
      gen_lists

      db_set apt-cacher-ng/gentargetmode "No automated setup"
      db_go
      ;;
      "Create now and update later"|"Set up now and update later")
      gen_lists
      ;;
      "No automated setup")
      ;;
   esac

   db_get $NAME/bindaddress
   BINDADDRESS="$RET"
   if [ x"$BINDADDRESS" = x"all" ] ; then # just for backwards compatibility
      BINDADDRESS='BindAddress: '
   elif [ x"$BINDADDRESS" = x"keep" ] ; then
      BINDADDRESS='# BindAddress set to "keep", not overriding here'
   else
      BINDADDRESS="BindAddress: $BINDADDRESS"
   fi

   db_get $NAME/port
   PORT="$RET"
   if [ x"$PORT" = x"keep" ] || [ x"$PORT" = x ] ; then
      PORT='# Port set to "keep", not overriding here'
   else
      PORT="Port: $PORT"
   fi

   db_get $NAME/proxy
   PROXY="$RET"
   if [ x"$PROXY" = x ] ; then
      PROXY='Proxy:'
   elif [ x"$PROXY" = x"keep" ] ; then
      PROXY='# Proxy set to "keep", not overriding here'
   else
      if echo "$PROXY" |grep -q '@' ; then
         # well, there are credentials which is bad. This better goes into a file with restricted permissions.
         install -m 640 -o root -g $NAME /dev/null $CFG/zz_debconf_security.conf
         cat << HERESEC >$CFG/zz_debconf_security.conf
# This file is created if the proxy contains user/password data
# and is removed otherwise.
Proxy: $PROXY        
HERESEC
         PROXY=
      else
         PROXY="Proxy: $PROXY"
         rm -rf $CFG/zz_debconf_security.conf
      fi
   fi

   PTENABLE='# PassThroughPattern: setting is not configured by debconf'
   db_get $NAME/tunnelenable
   if [ x"$RET" = x"true" ] ; then
      PTENABLE='PassThroughPattern: .*'
   fi

   cat << HERE > $CONFIGFILE
# This is a configuration generated file managed by the package configuration
# scripts of apt-cacher-ng. All manual changes here will be overriden.
# To reconfigure particular settings, please run:
# dpkg-reconfigure apt-cacher-ng -plow

# See acng.conf and apt-cacher-ng documentation for more details.
# To override this values permanently, put the assignments into a file
# like /etc/apt-cacher-ng/zzz_override.conf .

$PROXY
$PORT
$BINDADDRESS
$CDIRCONF
$PTENABLE

HERE

   db_stop || true

   rm -f $CFG/in.acng $CFG/mount.acng

   set_def_files
fi

# Automatically added by dh_systemd_enable/13.7.1
if [ "$1" = "configure" ] || [ "$1" = "abort-upgrade" ] || [ "$1" = "abort-deconfigure" ] || [ "$1" = "abort-remove" ] ; then
	# This will only remove masks created by d-s-h on package removal.
	deb-systemd-helper unmask 'apt-cacher-ng.service' >/dev/null || true

	# was-enabled defaults to true, so new installations run enable.
	if deb-systemd-helper --quiet was-enabled 'apt-cacher-ng.service'; then
		# Enables the unit on first installation, creates new
		# symlinks on upgrades if the unit file has changed.
		deb-systemd-helper enable 'apt-cacher-ng.service' >/dev/null || true
	else
		# Update the statefile to add new symlinks (if any), which need to be
		# cleaned up on purge. Also remove old symlinks.
		deb-systemd-helper update-state 'apt-cacher-ng.service' >/dev/null || true
	fi
fi
# End automatically added section
# Automatically added by dh_installinit/13.7.1
if [ "$1" = "configure" ] || [ "$1" = "abort-upgrade" ] || [ "$1" = "abort-deconfigure" ] || [ "$1" = "abort-remove" ] ; then
	# In case this system is running systemd, we need to ensure that all
	# necessary tmpfiles (if any) are created before starting.
	if [ -z "${DPKG_ROOT:-}" ] && [ -d /run/systemd/system ] ; then
		systemd-tmpfiles --create apt-cacher-ng.conf >/dev/null || true
	fi
fi
# End automatically added section
# Automatically added by dh_installinit/13.7.1
if [ "$1" = "configure" ] || [ "$1" = "abort-upgrade" ] || [ "$1" = "abort-deconfigure" ] || [ "$1" = "abort-remove" ] ; then
	if [ -z "${DPKG_ROOT:-}" ] && [ -x "/etc/init.d/apt-cacher-ng" ]; then
		update-rc.d apt-cacher-ng defaults 18 >/dev/null
		if [ -n "$2" ]; then
			_dh_action=restart
		else
			_dh_action=start
		fi
		invoke-rc.d apt-cacher-ng $_dh_action || exit 1
	fi
fi
# End automatically added section