#!/bin/bash
#==============================================================================
# This script is intended to automatically set up a schroot environment ready
# to compile the kernel.
# The arguments are the same as for the debootstrap command. The entry for
# the schroot configuration will be automatically appended (if it does not
# exist) and the remaining packages will get installed.
#==============================================================================
RC=0
USER="$SUDO_USER"
if [ "$USER" = "" ]; then
	echo "ERROR: You must run this command under sudo!" >&2
	RC=1
fi
if [ $(id -u) -ne 0 ]; then
	echo "ERROR: You must be root to run this command!" >&2
	RC=1
fi
for i in debootstrap schroot; do
	if [ "$(type -p $i)" = "" ]; then
		echo "ERROR: $i is required!" >&2
		RC=1
	fi
done

if [ $RC -ne 0 ]; then
	exit $RC
fi

#------------------------------------------------------------------------------
# Command line evaluation
#------------------------------------------------------------------------------
OPTIONS=""
SUITE=""
TARGET=""
MIRROR=""
while [ $# -ne 0 ]; do
	case $1 in
		--arch=*)
			ARCH=$(echo $1|cut -d= -f2)
			OPTIONS="$OPTIONS $1"
			;;
		-*|--*)
			OPTIONS="$OPTIONS $1"
			;;
		*)
			if [ "$SUITE" = "" ]; then
				SUITE="$1"
			elif [ "$TARGET" = "" ]; then
				TARGET="$1"
			elif [ "$MIRROR" = "" ]; then
				MIRROR="$1"
			else
				echo "Too many arguments <$1>!" >&2
				exit 1
			fi
			;;
	esac
	shift
done

if [ "$SUITE" = "" -o "$TARGET" = "" ]; then
	echo "$(basename $0) <suite> <target> [mirror]"
	exit 1
fi

#------------------------------------------------------------------------------
# Make a list of package we additionally need (depending on suite).
#------------------------------------------------------------------------------
ADDPKG="vim fakeroot git-core kernel-wedge build-essential ccache"
case $SUITE in
	dapper)
		ADDPKG="$ADDPKG kernel-package"
		;;
	feisty)
		ADDPKG="$ADDPKG kernel-package"
		;;
	gutsy)
		;;
	hardy)
		;;
	intrepid)
		ADDPKG="$ADDPKG makedumpfile"
		;;
	jaunty)
		ADDPKG="$ADDPKG makedumpfile"
		;;
	*)
		if [ "$SUITE" != "" ]; then
			echo "Unknown suite <$SUITE>!" >&2
			exit 1
		fi
		;;
esac

HOSTARCH=$(dpkg --print-architecture)
if [ "$ARCH" = "" ]; then
	NAME="$SUITE"
else
	NAME="$SUITE-$ARCH"
fi

CFGFILE="/etc/schroot/schroot.conf"
CFGEXISTS=false
if [ "$(fgrep "[$NAME]" $CFGFILE 2>/dev/null)" != "" ]; then
	echo "WARNING: An entry for $NAME already exists in $CFGFILE!" >&2
	CFGEXISTS=true
fi

DOINSTALL=true
if [ ! -d "$TARGET" ]; then
	mkdir "$TARGET"
	if [ $? -ne 0 ]; then
		echo "Failed to create <$TARGET>!" >&2
		exit 1
	fi
else
	if $CFGEXISTS; then
		echo "WARNING: Target directory exists as well. " \
		     "Skipping installation" >&2
		DOINSTALL=false
	fi
fi

if $DOINSTALL; then
	echo debootstrap $OPTIONS $SUITE "$TARGET" $MIRROR
	debootstrap $OPTIONS $SUITE "$TARGET" $MIRROR || exit 1
	if [ -d "$TARGET/etc" ]; then
		cp /etc/hosts /etc/sudoers "$TARGET/etc"
	fi
fi

function UpdateConfig()
{
	echo "INFO: Updating configuration file..." >&2
	USER=$SUDO_USER
	cat <<-EOD >>$CFGFILE

	[$NAME]
	description=Ubuntu $SUITE ($ARCH)
	type=directory
	location=$TARGET
	users=$USER
	run-setup-scripts=true
	EOD
	case $ARCH in
		i386|lpia)
			case $HOSTARCH in
				amd64)
					echo "personality=linux32" >>$CFGFILE
					;;
			esac
			;;
	esac
}
if ! $CFGEXISTS; then
	UpdateConfig
fi
schroot -uroot -c$NAME -q apt-get -- install -y --force-yes $ADDPKG