#!/bin/bash

# Nagios script for LiteSpeed version check;
# Nagios status codes (Nagios expects one of these to be returned);
# OK = 0;
# WARNING = 1;
# CRITICAL = 2;
# UNKNOWN = 3;


function check_command_result() {
  if [ $? -eq 0 ]; then
    return
  else
    echo "CRITICAL: can't run command [${1}]"
    exit 2
  fi
}

VERBOSE=0
PROGNAME=${0##*/}
LITESPEED_VERSION_URL="https://update.litespeedtech.com/ws/latest.php"


print_usage() {
    echo ""
    echo "Usage: ${PROGNAME} [-v be Verbose]"
    echo "Usage: ${PROGNAME} -h | --help"
}

print_help() {
        print_usage
        echo ""
        echo "This script checks latest version of LiteSpeed "
        echo ""
        echo "-v be Verbose (should be last argument)"
        echo "--help Print this help screen"
        echo ""
        exit 3
}

while [ $# -gt 0 ]; do
        case "$1" in
        --help)
                print_help
                exit 3
                ;;
        -h)
                print_help
                exit 3
                ;;
        -v)
                VERBOSE=1; shift;shift
                ;;
        *)
                echo >&2 "Unknown argument: $1"
                print_usage
                exit 3
                ;;
        esac
        shift
done

# Get current LiteSpeed version;
CURRENT_VERSION=$(/usr/local/lsws/bin/litespeed -v)
check_command_result "/usr/local/lsws/bin/litespeed -v"

# Get available latest LiteSpeed version;
AVAILABLE_VERSION=$(curl ${LITESPEED_VERSION_URL})
check_command_result "curl ${LITESPEED_VERSION_URL}"

# Parse current LiteSpeed verion from common string;
RESULT_CURRENT_VERSION=$(awk -F" " '{print $1}' <<< ${CURRENT_VERSION})
check_command_result "awk"
RESULT_CURRENT_VERSION=$(awk -F"/" '{print $2}' <<< ${RESULT_CURRENT_VERSION})
check_command_result "awk"

# Parse latest stable LiteSpeed version from common string;
RESULT_AVAILABLE_VERSION=$(awk -F"LSWS_STABLE=" '{print $2}' <<< ${AVAILABLE_VERSION})
check_command_result "awk"
RESULT_AVAILABLE_VERSION=$(echo "${AVAILABLE_VERSION}" | grep -oP 'LSWS_STABLE=\K[^ ]+')
check_command_result "awk"


if [[ ${VERBOSE} == 1 ]]; then
  echo -e "\n\t[VERBOSE INFORMATION, begin]\n"
  echo "Current version, full string: [${CURRENT_VERSION}]"
  echo "Available version, full list (curl response): [${AVAILABLE_VERSION}]"
  echo "Parsed current version string: [${RESULT_CURRENT_VERSION}]"
  echo "Parsed all versions string: [${RESULT_AVAILABLE_VERSION}]"
  echo -e "\n\t[ VERBOSE INFORMATION, end ]\n"
fi

# Check curl data;
if [[ ${AVAILABLE_VERSION} != *"LSWS_STABLE"* ]]; then
  echo "CRITICAL: curl response didn't contain LSWS_STABLE data."
  exit 2
fi

# Final check;
if [[ "${RESULT_CURRENT_VERSION}" == "${RESULT_AVAILABLE_VERSION}" ]]; then
    echo "OK: LiteSpeed version is updated: [${RESULT_AVAILABLE_VERSION}]"
    exit 0
else
    echo "CRITICAL: LiteSpeed version is outdated, latest version: [${RESULT_AVAILABLE_VERSION}]"
    exit 2
fi