#!/bin/bash

# Copyright Security Onion Solutions LLC and/or licensed to Security Onion Solutions LLC under one
# or more contributor license agreements. Licensed under the Elastic License 2.0; you may not use
# this file except in compliance with the Elastic License 2.0.
{% from 'vars/globals.map.jinja' import GLOBALS %}
{% from 'elasticfleet/map.jinja' import ELASTICFLEETMERGED %}

. /usr/sbin/so-common

# Only run on Managers
if ! is_manager_node; then
    printf "Not a Manager Node... Exiting"
    exit 0
fi

function update_fleet_urls() {
	# Generate updated JSON payload
    JSON_STRING=$(jq -n --arg UPDATEDLIST $NEW_LIST_JSON '{"name":"grid-default","is_default":true,"host_urls": $UPDATEDLIST}')

    # Update Fleet Server URLs
    curl -K /opt/so/conf/elasticsearch/curl.config -L -X PUT "localhost:5601/api/fleet/fleet_server_hosts/grid-default" -H 'kbn-xsrf: true' -H 'Content-Type: application/json' -d "$JSON_STRING"
}

# Get current list of Fleet Server URLs
RAW_JSON=$(curl -K /opt/so/conf/elasticsearch/curl.config 'http://localhost:5601/api/fleet/fleet_server_hosts/grid-default' --retry 3 --retry-delay 30 --fail 2>/dev/null)

# Check to make sure that the server responded with good data - else, bail from script
CHECKSUM=$(jq -r '.item.id' <<< "$RAW_JSON")
if [ "$CHECKSUM" != "grid-default" ]; then
 printf "Failed to query for current Fleet Server URLs..."
 exit 1
fi

# Get the current list of Fleet Server URLs & hash them
CURRENT_LIST=$(jq -c -r '.item.host_urls' <<<  "$RAW_JSON")
CURRENT_HASH=$(sha1sum <<< "$CURRENT_LIST" | awk '{print $1}')

# Create array & add initial elements
if [ "{{ GLOBALS.hostname }}" = "{{ GLOBALS.url_base }}" ]; then
    NEW_LIST=("https://{{ GLOBALS.url_base }}:8220")
else
    NEW_LIST=("https://{{ GLOBALS.url_base }}:8220" "https://{{ GLOBALS.hostname }}:8220")
fi

# Query for FQDN entries & add them to the list
{% if ELASTICFLEETMERGED.config.server.custom_fqdn | length > 0 %}
CUSTOMFQDNLIST=('{{ ELASTICFLEETMERGED.config.server.custom_fqdn | join(' ') }}')
readarray -t -d ' ' CUSTOMFQDN < <(printf '%s' "$CUSTOMFQDNLIST")
for CUSTOMNAME in "${CUSTOMFQDN[@]}"
do
 NEW_LIST+=("https://$CUSTOMNAME:8220")
done
{% endif %}

# Query for the current Grid Nodes that are running Logstash (which includes Fleet Nodes)
LOGSTASHNODES=$(salt-call --out=json pillar.get logstash:nodes | jq '.local')

# Query for Fleet Nodes & add them to the list (Hostname)
if grep -q "fleet" <<< $LOGSTASHNODES; then
   readarray -t FLEETNODES < <(jq -r ' .fleet | keys_unsorted[]'  <<< $LOGSTASHNODES)
   for NODE in "${FLEETNODES[@]}"
   do
    NEW_LIST+=("https://$NODE:8220")
   done
fi

# Sort & hash the new list of Fleet Server URLs
NEW_LIST_JSON=$(jq --compact-output --null-input '$ARGS.positional' --args -- "${NEW_LIST[@]}")
NEW_HASH=$(sha1sum <<< "$NEW_LIST_JSON" | awk '{print $1}')

# Compare the current & new list of URLs - if different, update the Fleet Server URLs & regenerate the agent installer
if [ "$NEW_HASH" = "$CURRENT_HASH" ]; then
    printf "\nHashes match - no update needed.\n"
    printf "Current List: $CURRENT_LIST\nNew List: $NEW_LIST_JSON\n"
    exit 0
else
    printf "\nHashes don't match - update needed.\n"
    printf "Current List: $CURRENT_LIST\nNew List: $NEW_LIST_JSON\n"
    update_fleet_urls
    /sbin/so-elastic-agent-gen-installers >> /opt/so/log/elasticfleet/so-elastic-agent-gen-installers.log &
fi
