#!/bin/sh
#
# managing our work at the cryptobox
#
# development actions:
#   chroot	- run first tests in a chroot environment
#   qemu	- run the qemu emulation
#   upload	- copy your local files to tmpfs on a running cryptobox
#   diff	- compare tmpfs-files on a running cryptobox with the original
#   merge	- apply the diff to the local copy
#
# problems of this script:
#  - chroot has to run as root
#

set -ue

# get the path of a configuration file - local configuration files
# supersede default files
# parameter: base name of the configuration file
function get_config_file()
{
	[ -e "$LOCALCONF_DIR/$1" ] && echo "$LOCALCONF_DIR/$1" && return 0
	[ -e "$DEFAULTCONF_DIR/$1" ] && echo "$DEFAULTCONF_DIR/$1" && return 0
	echo "configuration file ($1) not found!" >&2
	exit 1
}


# the base directory of your local development files
ROOT_DIR=$(dirname "$0")

# the template (default) configuration directory
DEFAULTCONF_DIR="$ROOT_DIR/etc-defaults.d"

# your local configuration directory (existing files supersede the defaults)
LOCALCONF_DIR="$ROOT_DIR/etc-local.d"

# local configuration directory - contains scripts to be executed after
# 'configure'
CUSTOM_CONFIGURE_DIR="$ROOT_DIR/configure-local.d"

# template directory for cryptobox specific configuration
TEMPLATE_DIR="cbox-tree.d"

# the chroot-wrapper within the cryptobox
CHROOT_START="/usr/lib/cryptobox/chroot-start.sh"

# qemu network configuration file
QEMU_IFUP_FILE=$(get_config_file qemu-ifup)

# to connect to a development cryptobox with ssh
SSH_CONFIG_FILE=$(get_config_file ssh_config)

# extract the hostname of the cryptobox from the ssh_config file
SSH_HOST=$(grep "^Host " "$SSH_CONFIG_FILE" | head -1 | sed 's/^Host *\(.*\)$/\1/')


############# include local configuration ##############

if [ -e "$(get_config_file cbox-dev.conf)" ]
	then	source "$(get_config_file cbox-dev.conf)"
	else	echo "local cbox-dev.conf ($(get_config_file cbox-dev.conf)) does not exist!" >&2
		exit 1
  fi

# image directory created by dfsbuild
# the BUILD_DIR is defined in the local cbox-dev.conf
IMAGE_DIR="$BUILD_DIR/image"

# read some cryptobox settings (especially "DEV_FEATURES_SCRIPT")
if [ -e "$TEMPLATE_DIR/etc/cryptobox/cryptobox.conf" ]
	then	source "$TEMPLATE_DIR/etc/cryptobox/cryptobox.conf"
	else	echo "cryptobox.conf ($TEMPLATE_DIR/etc/cryptobox/cryptobox.conf) does not exist!" >&2
  fi

####################### functions ######################


function qemu_boot()
{
	# create a virtual harddisk image file
	if [ ! -e "$HD_IMAGE" ]
		then	echo "Creating temporary harddisk image ..."
			dd if=/dev/zero of="$HD_IMAGE" bs=1M count=20
	  fi
	echo "Starting qemu ..."
	qemu -cdrom "$IMAGE_FILE" -m 96 -hda "$IMAGE_FILE" -boot d -n "$QEMU_IFUP_FILE" || true
	# remove iptables rules
	"$QEMU_IFUP_FILE" stop
}


function upload2box()
# upload local files to a development cryptobox
# this is necessary to use an "old" development cd with
# new code - this affects only the web-interface and the
# cbox-manage.sh-script (the boot behaviour stays the same)
#
# of course, only the directories that are mapped to tmpfs can
# be updated this way
{
	local DIRS="var/www usr/share/cryptobox usr/lib/cryptobox"
	[ -e "$TMP_DIR" ] || mkdir -p "$TMP_DIR"
	for a in $DIRS
		do	mkdir -p "$TMP_DIR/$a"
			cp -r "$TEMPLATE_DIR/$a/." "$TMP_DIR/$a"
	  done
	find "$TMP_DIR" -type d -name '\.svn' | while read a
		do	rm -rf "$a"
	  done
	echo "Copying local files to the cryptobox ... "
	if scp -F "$SSH_CONFIG_FILE" -rpq "$TMP_DIR/." cryptobox:/tmp/mirror 
		then	echo "Set the base for future diffs to current state ..."
			ssh -F "$SSH_CONFIG_FILE" "$SSH_HOST" "$DEV_FEATURES_SCRIPT" set_diff_base
		else	echo 'ERROR: copying failed!'
	  fi
	rm -rf "$TMP_DIR"
}
 

function merge_from_box()
# merge a diff from a running development cryptobox into
# your local copy
{
	echo "Check for collisions ... (dry-run)"
	if box_diff | patch --dry-run -p1 -d "$TEMPLATE_DIR"
	  then	echo
	  	echo "Applying diff ..."
		box_diff | patch -p1 -d "$TEMPLATE_DIR"
		echo
		echo "Set the base for future diffs to current state ..."
		ssh -F "$SSH_CONFIG_FILE" "$SSH_HOST" "$DEV_FEATURES_SCRIPT" set_diff_base
	  else	echo "Merging will fail - do it manually!"
	 fi
}


# get the diff of a running cryptobox system between its current state
# and its original content
function box_diff()
{
	ssh -F "$SSH_CONFIG_FILE" "$SSH_HOST" "$DEV_FEATURES_SCRIPT" diff
}


############################# main #####################################

[ $# -eq 0 ] && echo "[`basename $0`] - no arguments supplied - maybe you want to use '--help'"

ACTION=--help
[ $# -gt 0 ] && ACTION=$1

case "$1" in
	diff )
		# get a diff from a running development cryptobox
		box_diff
		;;
	merge )
		merge_from_box
		;;
	upload )
		upload2box
		;;
	chroot )
		# chroot may only be called as root
		[ "$(id -u)" -ne 0 ] && echo "the action 'chroot' may only be called as root!" >&2 && exit 1
		if [ ! -x "$IMAGE_DIR/$CHROOT_START" ]
		   then	echo "the chroot init script ("$IMAGE_DIR/$CHROOT_START") is not executable"
			echo "maybe you should run '`basename $0` cb-config' first"
		   else	chroot "$IMAGE_DIR" "$CHROOT_START"
		  fi
		;;
	qemu )
		qemu_boot
		;;
	ssh )
		ssh -F "$SSH_CONFIG_FILE" "$SSH_HOST" 
		;;
	help|--help )
		echo "Syntax: `basename $0` ( qemu | chroot | upload | diff | merge | ssh | help )"
		echo
		;;
	* )
		echo -e "unknown action: $1"
		echo
		$0 help
		exit 1
		;;
  esac