#!/bin/bash
if [ "$#" -ne 2 ]; then
    echo "Illegal number of parameters! Pass the new instance type and instance id..."
else

type=$1
instance=$2

aws ec2 stop-instances --instance-ids $instance
while [ "`aws ec2 describe-instances --instance-ids $instance --output text --query 'Reservations[*].Instances[*].State.Name'`" != "stopped" ]
do
 echo "Instance is stopping..."
 sleep 1
done

echo -e  "Instance is stopped \n Changing instance type..."
aws ec2 modify-instance-attribute --instance-id $instance --instance-type "{\"Value\": \"$type\"}"
sleep 4
echo "Start the instance..."
aws ec2 start-instances --instance-ids $instance
while [ "`aws ec2 describe-instances --instance-ids $instance --output text --query 'Reservations[*].Instances[*].State.Name'`" != "running" ]
do
 echo "Instance is starting..."
 sleep 1
done

echo "Instance is started..."
fi