#!/bin/sh

set -eu

if [ "$#" -lt "2" ]; then
  echo >&2 "Usage: h-ssh <ENV> <APP> [SSH_ARGS]"
  exit 1
fi

ENV=$1
APP=$2
shift 2

pickhost() {
  local app=$1
  local env=$2
  aws ec2 describe-instances \
    --filters "Name=tag:application,Values=${app}" \
              "Name=tag:environment,Values=${env}" \
              "Name=instance-state-name,Values=running" \
    --query "Reservations[0].Instances[0].PublicDnsName" \
    --output text
}

if ! HOSTNAME=$(pickhost "$APP" "$ENV"); then
  echo >&2 "Error running awscli! Aborting."
  exit 1
elif [ "$HOSTNAME" = "None" ]; then
  echo >&2 "Couldn't find any matching hosts! Is that the right application name?"
  exit 1
fi

ssh \
  -l ec2-user \
  -o UserKnownHostsFile=/dev/null \
  -o StrictHostKeychecking=no \
  "$HOSTNAME" \
  "$@"