#!/bin/bash
#
# Source:
# https://gitea.evolix.org/evolix/ansible-roles/src/branch/stable/nagios-nrpe
#

readonly PROGNAME=$(basename $0)
readonly VERSION="24.04.00"

# Load common functions and vars
readonly lib_dir="/usr/local/lib/monitoringctl"
if [ -r "${lib_dir}/common" ]; then
    # shellcheck source=monitoringctl_common
    source "${lib_dir}/common"
else
    >&2 echo "Error: missing ${lib_dir}/common file."
    exit 1
fi

function show_help() {
    cat <<END
$PROGNAME disables or enables NRPE alerts wrapped by the script 'alerts_wrapper' in NRPE configuration.

Usage: $PROGNAME disable [-d|--during <DURATION>] [--message '<DISABLE_MESSAGE>'] <WRAPPER_NAME|all>
       $PROGNAME enable [--message '<ENABLE_MESSAGE>'] <WRAPPER_NAME|all>
       $PROGNAME help

WRAPPER_NAME:    The name given to '--name' option of 'alerts_wrapper'.
DURATION:        Duration of alert disabling.
                 Can be '1d' for 1 day, '5m' for 5 minutes or more complex
                 expressions like '1w2d10m42s' (if no time unit is provided,
                 hour is assumed)
                 Default value: 1h
DISABLE_MESSAGE: Message that will be logged and printed by alerts_wrapper
                 when alert is disabled.
ENABLE_MESSAGE:  Message that will be logged when alert is enabled
END
}

function disable_alerts() {
    # $1: wrapper name, $2: duration_sec, $3: disable message
    now_secs=$(date +"%s")
    disable_until_secs=$(( now_secs + ${2} ))
    disable_file_path="$(get_disable_file_path "${1}")"
    echo "${disable_until_secs}" > "${disable_file_path}"
    echo "$(logname || echo unknown): \"${3}\"" >> "${disable_file_path}"
    chmod 0644 "${disable_file_path}"
    log "${1} alerts disabled by $(logname || echo unknown)"
    log "Disable message: ${3}"
}

function enable_alerts() {
    # $1: wrapper name, $2: enable message
    disable_file_path="$(get_disable_file_path "${1}")"
    if [ -e "${disable_file_path}" ]; then
        rm "${disable_file_path}"
    fi
    log "${1} alerts enabled by $(logname || echo unknown)"
    log "Enable message: ${2}"
}

function main() {
    install --mode=0755 --directory "${var_dir}"

    if [ "${action}" == 'enable' ]; then
        if [ "${wrapper_name}" == "all" ]; then
            for wrapper in $(get_wrappers_names); do
                enable_alerts "${wrapper}" "${message}"
            done
        else
            enable_alerts "${wrapper_name}" "${message}"
        fi
    elif [ "${action}" == 'disable' ]; then
        duration_sec=$(time_to_seconds "${duration}")
        if [ "${wrapper_name}" == "all" ]; then
            for wrapper in $(get_wrappers_names); do
                disable_alerts "${wrapper}" "${duration_sec}" "${message}"
            done
        else
            disable_alerts "${wrapper_name}" "${duration_sec}" "${message}"
        fi
    elif [ "${action}" == 'help' ]; then
        show_help
    fi
}


while :; do
    case "${1}" in
        enable|disable|help)
            action="${1}"
            shift;;
        -d|--during)
            if [ "$#" -gt 1 ]; then
                if filter_duration "${2}"; then
                    duration="${2}"
                else
                    usage_error "Option --during: \"${2}\" is not a valid duration."
                fi
            else
                error "Missing --during argument."
            fi
            shift; shift;;
        -m|--message)
            if [ "$#" -gt 1 ]; then
                message="${2}"
            else
                error "Missing --message argument."
            fi
            shift; shift;;
        *)
            if [ -n "${1}" ]; then
                if is_wrapper "${1}" || [ "${1}" == "all" ]; then
                    wrapper_name="${1}"
                else
                    error "Unknown argument '${1}', or NAME not defined in NRPE configuration."
                fi
            else
                if [ -z "${action}" ]; then
                    error "Missing action argument."
                elif [ -z "${1}" ]; then
                    break
                fi
            fi

            shift;;
    esac
done

if [ -z "${wrapper_name}" ] && [ "${action}" != 'help' ] ; then
    error "Missing WRAPPER_NAME."
fi

if [ -z "${duration}" ]; then
    duration="${default_disabled_time}"
fi

readonly wrapper_name duration action

main