#!/bin/bash
# Clone a base virtual machine to create a new node
#
# Example usage:
#    vn-clonebase base node1
# uses the virtual machine called "base" to create a (linked) clone called
# "node1". 
#
# Assumptions:
# The base virtual machine MUST have a snapshot with the same name as the 
# virtual machine. For example the VM called "base" must also have a snapshot
# called "base". It is this snapshot that is cloned.
#
# Design:
#    1. Check the target VM does not already exist
#    2. Use VBoxManage to clone the base VM to produce the target VM
#
# For more info see: http://sandilands.info/sgordon/virtnet
#
# $Revision$
# $Author$
# $Date$
# $URL$

# Input parameters
# Name of the base virtual machine (to clone)
basevm=$1

# Name of the target virtual machine (the newly created VM)
vmname=$2

# Check if the vm to create already exists; do not clone if it does
VBoxManage list vms | cut -d "\"" -f 2 | grep -w ${vmname} > /dev/null
vmmatch=$?
if [ "${vmmatch}" != "1" ];
then
	# If a VM with vmname already exists, then rename the old one
	newname=`date +'%y%m%d%H%M%S'`${vmname}
	echo "vn: Virtual machine ${vmname} already exists."
	echo "vn: Will try to rename the old one to ${newname} ..."
	VBoxManage modifyvm ${vmname} --name ${newname} > /dev/null
	vmfail=$?
	if [ "${vmfail}" = "1" ];
	then
		echo "vn: Failed to rename the old ${vmname} to ${newname}"
		echo "vn: Make sure the old ${vmname} is NOT running and/or rename"
		echo "vn: it to something other then ${vmname} then try to create"
		echo "vn: the topology again."
		echo "vn: ERROR. Exiting..."
		exit 1
	fi
	echo "vn: Successfully renamed ${vmname} to ${newname}."
fi

# Check to see if any old directories for past node exists
#	defaultvmdir=`VBoxManage list systemproperties | grep "Default machine folder" | cut -d ":" -f 2`;

# Check to see if the snapshot exists; if not, take it
VBoxManage snapshot ${basevm} list 2> /dev/null
snmatch=$?
if [ "${snmatch}" = "0" ]; # Has snapshots
then
	VBoxManage snapshot ${basevm} list --machinereadable | grep "SnapshotName" | grep -w ${basevm} > /dev/null
	snmatch=$?
	if [ "${snmatch}" = "1" ]; # basvm snapshot doesn't exist
	then
		# Take snapshot
		echo "vn: VM ${basevm} does not have snapshot called ${basevm}"
		echo "vn: Taking snapshot of ${basevm} (snapshot also called ${basevm})"
		VBoxManage snapshot ${basevm} take ${basevm}
	else
		echo "vn: VM ${basevm} already has snapshot ${basevm}"
	fi
else
	# Take snapshot
	echo "vn: VM ${basevm} does not have any snapshots"
	echo "vn: Taking snapshot of ${basevm} (snapshot also called ${basevm})"
	VBoxManage snapshot ${basevm} take ${basevm}
fi

# Clone the base vm (specifically the snapshot of the base)
VBoxManage clonevm ${basevm} --name ${vmname} --snapshot ${basevm} --options link --register
echo "vn: Virtual machine ${basevm} cloned to ${vmname}"
exit 0