#!/bin/bash

# Todo: This should go into a yaml file
query_imds() {
  MAC=$(imds meta-data/mac)
  AVAILABILITY_ZONE=$(imds meta-data/placement/availability-zone)
  REGION=$(echo ${AVAILABILITY_ZONE} | sed "s/[a-z]$//")
  INSTANCE_ID=$(imds meta-data/instance-id)

  cat <<EOF >> /var/lib/cloud/meta-data
AVAILABILITY_ZONE=$AVAILABILITY_ZONE
REGION=$REGION
INSTANCE_ID=$INSTANCE_ID
IP_ADDRESS=$(imds meta-data/local-ipv4)
PUBLIC_IP_ADDRESS=$(imds meta-data/public-ipv4 || true)
DEFAULT_GW_INTERFACE=$(ip -o route get 8.8.8.8 | awk '{print $5}')
MAC=$MAC
VPC_CIDR_RANGE=$(imds meta-data/network/interfaces/macs/${MAC}/vpc-ipv4-cidr-block)
SUBNET=$(imds meta-data/network/interfaces/macs/${MAC}/subnet-ipv4-cidr-block)
_META_HOSTNAME=$(imds meta-data/hostname)
DOMAIN_NAME=\${_META_HOSTNAME#*.}
AWS_ACCOUNT_ID=$(imds meta-data/network/interfaces/macs/${MAC}/owner-id)
INSTANCE_LIFE_CYCLE=$(imds meta-data/instance-life-cycle)
INSTANCE_TYPE=$(imds meta-data/instance-type)
EOF
}

# Todo: This should go into a yaml file
get_tags() {
  # via metadata AWS restricts tags to NOT have " " or "/" ;-(
  # Replace all /:.- with _ for valid variable names
  for key in $(imds meta-data/tags/instance); do
    value="$(imds meta-data/tags/instance/$key)"
    key=$(echo ${key//[\/:.-]/_} | tr '[:lower:]' '[:upper:]')
    echo "$key=\"$value\"" >> /var/lib/cloud/meta-data
  done
  #while read _key value; do
  #  key=$(echo ${_key//[\/:.-]/_} | tr '[:lower:]' '[:upper:]')
  #  echo "$key=\"$value\"" >> /var/lib/cloud/meta-data
  #done < <(aws ec2 describe-tags --filters "Name=resource-id,Values=${INSTANCE_ID}" --query 'Tags[*].[Key,Value]' --region $REGION --output text)
}

# extract user-data args and cloud meta-data into /var/lib/cloud/meta-data
get_meta_data() {
  if [ ! -f /var/lib/cloud/meta-data ]; then
    echo '#!/bin/bash' > /var/lib/cloud/meta-data

    query_imds
    get_tags
  fi

  if [ ! -f /etc/cloudbender.conf ]; then
    bash /var/lib/cloud/user-data extract_parameters
  fi
}

import_meta_data() {
  . /etc/cloudbender.conf
  . /var/lib/cloud/meta-data

  export AWS_DEFAULT_REGION=$REGION
  export AWS_DEFAULT_OUTPUT=text

  # Enabled LaunchHooks if not DEBUG
  is_enabled $ZDT_CLOUDBENDER_DEBUG || LAUNCH_HOOK="CloudBenderLaunchHook"

  # Workaround for current CFN ASG_<parameter> hack
  _key=$(echo $AWS_CLOUDFORMATION_LOGICAL_ID | tr '[:lower:]' '[:upper:]')
  [ -n "$(eval echo \$${_key}_CUSTOMHOSTNAME)" ] && CUSTOMHOSTNAME="$(eval echo \$${_key}_CUSTOMHOSTNAME)"
  [ -n "$(eval echo \$${_key}_VOLUMES)" ] && VOLUMES="$(eval echo \$${_key}_VOLUMES)"

  return 0
}

# various early volume functions
attach_ebs() {
  local volId="$1"
  local device="$2"

  local tries=30
  while true; do
    _json="$(aws ec2 describe-volumes --volume-ids $volId --region $REGION --output json)"
    rc=$?; [ $rc -ne 0 ] && return $rc

    vol_status=$(echo "$_json" | jq -r .Volumes[].State)
    attachedId=$(echo "$_json" | jq -r .Volumes[].Attachments[].InstanceId)

    [ "$attachedId" = "$INSTANCE_ID" ] && break

    if [ "$vol_status" = "available" ]; then
      aws ec2 attach-volume --volume-id "$volId" --instance-id "$INSTANCE_ID" --region "$REGION" --device "$device" > /dev/null
      rc=$?; [ $rc -ne 0 ] && return $rc
      break
    fi

    # if attached but not to us -> detach
    if [ "$vol_status" = "in-use" ]; then
      aws ec2 detach-volume --volume-id "$volId" --region "$REGION" --force
      rc=$?; [ $rc -ne 0 ] && return $rc
    fi

    ((tries=tries-1))
    [ $tries -eq 0 ] && return 1
    sleep 5
  done
}

asg_heartbeat() {
  [ -n "$LAUNCH_HOOK" ] && aws autoscaling record-lifecycle-action-heartbeat --instance-id $INSTANCE_ID --lifecycle-hook-name $LAUNCH_HOOK --auto-scaling-group-name $AWS_AUTOSCALING_GROUPNAME || true
}

setup_sns_alarms() {
  # store SNS message json template
  cat <<EOF > /var/lib/cloud/sns_alarm.json
{
  "Source": "CloudBender",
  "AWSAccountId": "$AWS_ACCOUNT_ID",
  "Region": "$REGION",
  "Artifact": "$ARTIFACT",
  "Asg": "$AWS_AUTOSCALING_GROUPNAME",
  "Instance": "$INSTANCE_ID",
  "ip": "$IP_ADDRESS"
}
EOF

  cat <<'EOF' > /var/lib/cloud/sns_alarm.sh
#!/bin/bash

SUBJECT=$1
MSG=$2
LEVEL=${3:-Info}
ATTACHMENT=${4:-""}
EMOJI=${5:-""}
EOF
  if [ -n "$ALARMSNSARN" ]; then
    cat <<EOF >> /var/lib/cloud/sns_alarm.sh
jq -M --arg subject "\$SUBJECT" --arg level "\$LEVEL" --arg msg "\$MSG" --arg attachment "\$ATTACHMENT" --arg emoji "\$EMOJI" --arg hostname "\$HOSTNAME" '.Subject = \$subject | .Level = \$level | .Message = \$msg | .Attachment = \$attachment | .Emoji = \$emoji | .Hostname = \$hostname' < /var/lib/cloud/sns_alarm.json | sed -e 's/\\\\\\\\/\\\\/g' > /tmp/sns.json
aws sns publish --region ${REGION} --target-arn $ALARMSNSARN --message file:///tmp/sns.json
EOF
  fi

  chmod +x /var/lib/cloud/sns_alarm.sh
}

# associate EIP
# return 0 if we attached an EIP
# return 1 if we the public IP did NOT change or other error
associate_eip() {
  local instance_id=$1
  local eip=$(echo $2 | sed -e 's/\/32//' | grep -E -o "(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)") || true
  local current_instance

  if [ -n "$eip" ]; then
    if [ "$eip" != "0.0.0.0" ]; then
      read eip_alloc_id eip_assoc_id current_instance  < <(aws ec2 describe-addresses --public-ips $eip --query 'Addresses[*].[AllocationId,AssociationId,InstanceId]' || true)

      # If we already own and have the EIP attached -> done
      [ "$instance_id" == "$current_instance" ] && return

      if [ ! -z "$eip_alloc_id" ]; then
        if [[ "$eip_assoc_id" =~ ^eipassoc- ]]; then
          log -t user-data info "EIP $eip already associated via Association ID ${eip_assoc_id}. Disassociating."
          retry 3 10 aws ec2 disassociate-address --association-id $eip_assoc_id
        fi

        log -t user-data info "Associating Elastic IP $eip via Allocation ID $eip_alloc_id with Instance $instance_id"
        aws ec2 associate-address --no-allow-reassociation --instance-id $instance_id --allocation-id $eip_alloc_id
        return

      else
        log -t user-data warn "Elastic IP $eip address not found."
      fi
    else
      log -t user-data info "0.0.0.0 requested, keeping AWS assigned IP."
    fi
  else
    log -t user-data debug "Invalid or no ElasticIP defined. Skip"
  fi

  return 1
}

# Accept incoming traffic for everything
disable_source_dest_check() {
  aws ec2 modify-instance-attribute --instance-id ${INSTANCE_ID} --source-dest-check "{\"Value\": false}"
}

# Register ourself at route tables
register_routes() {
  local rtb_id_list="$1"
  local route_cidr="$2"

  for cidr in ${route_cidr//,/ }; do
    if [ "$cidr" != "$VPC_CIDR_RANGE" ]; then
      for rt in ${rtb_id_list//,/ }; do
        if [[ "$rt" =~ ^rtb-[a-f0-9]*$ ]]; then
          aws ec2 create-route --route-table-id $rt --destination-cidr-block "${cidr}" --instance-id ${INSTANCE_ID} || \
          aws ec2 replace-route --route-table-id $rt --destination-cidr-block "${cidr}" --instance-id ${INSTANCE_ID}
        else
          log -t user-data warn "Invalid Route Table ID: $rt"
        fi
      done
    fi
  done
}