#!/bin/bash
# -*- sh -*-

set -e

: << =cut

=head1 NAME

turbostat_ - Multigraph plugin that monitors processor statistics using the turbostat tool

=head1 DESCRIPTION

turbostat reports processor topology, frequency, idle power-state statistics, temperature
and power on X86 processors. This plugin monitors those statistics with munin

STATUS: as most statistics reported by turbostat can also already be monitored by other munin 
plugins, currently only monitoring package watts is implemented.

NOTE: turbostat is a live monitoring tool and does not provide a way to aggregate statistics
between measurements. So similar to other munin plugins, note that values monitored using
turbostat are only snapshots on the moment that this plugin runs and might not tell you
anything about what happened between two measurements.

=head1 INSTALLATION

On debian systems turbostat is provided by either the linux-tools-generic or linux-cpupower package.
If you are running a custom kernel, you can also build turbostat as follows:

$ apt-get install build-essential git libcap-dev 
$ cd /usr/local/src
$ git clone --depth=1 -b "v$(uname -r | cut -d- -f1)" git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
$ cd linux-stable/tools/power/x86/turbostat
$ make
$ ./turbostat

=head1 CONFIGURATION

Turbostat needs to be run as root

The following environment variables are used by this plugin

  TURBOSTAT_PATH	- Path to the turbostat executable if not in PATH

[turbostat_*]
user root
env.TURBOSTAT_PATH /usr/local/src/linux-stable/tools/power/x86/turbostat/turbostat

=head1 REQUIREMENTS

- turbostat utility (see INSTALLATION)

=head1 AUTHOR

Copyright (C) 2025 pimlie

=head1 LICENSE

MIT

=head1 MAGIC MARKERS

 #%# family=auto
 #%# capabilities=autoconf,suggest

=cut

if [ -n "$MUNIN_LIBDIR" ]; then
	. "$MUNIN_LIBDIR/plugins/plugin.sh"
fi

PLUGIN_BASE="$(basename "$0")"

SUPPORTED_GRAPH_TYPES=("watt")

WATT_COLS=("PkgWatt" "CorWatt" "GFXWatt" "RAMWatt")
WATT_COL_LABELS=("Whole" "Core part" "Graphics" "RAM")

# Check if turbostat exists
function turbostat_exists {
	if [ -n "$TURBOSTAT_PATH" ]; then
		if [ ! -f "$TURBOSTAT_PATH" ] || [ ! -x "$TURBOSTAT_PATH" ]; then
			return 1
		fi
	elif command -v turbostat >/dev/null; then
		TURBOSTAT_PATH="turbostat"
	else
		return 1
	fi

	# Check if we can really run turbostat, because the command might be
	# executable but only return a WARNING that it needs to be installed
	$TURBOSTAT_PATH --help >/dev/null 2>&1
	if [ $? -gt 1 ]; then
		return 1
	fi

	return 0
}

# Emit config for package watt graph
function emit_watt_graph {
	local col label

	cat <<EOS
graph_title Package watts
graph_args --base 1000 -l 0
graph_vlabel Watt
graph_category sensors
graph_info Shows watts consumed by hw package
update_rate 60
EOS
	for key in ${!WATT_COLS[*]}; do
		col="${WATT_COLS[$key]}"
		label=${WATT_COL_LABELS[$key]}

		cat <<EOS
$col.label $label
$col.min 0
EOS
	done
}

# Emit package watt values from turbostat
function emit_watt_values {
	IFS=' ' read -ra watts < <($TURBOSTAT_PATH --Summary --quiet --show "$(join , "${WATT_COLS[@]}")" -n 1 | tail -n 1 | xargs)
	unset IFS
	for key in ${!WATT_COLS[*]}; do
		emit_value "${WATT_COLS[$key]}" "${watts[$key]}"
	done
}

# Emit multigraph header
function emit_multigraph_base {
	if [ -z "$1" ]; then
		echo "multigraph $PLUGIN_BASE"
	else
		echo "multigraph ${PLUGIN_BASE}${1//-/_}"
	fi
}

# Emit value for process
function emit_value {
	local graph_name
	graph_name="$1"

	echo "${graph_name}.value $2"
}

# Check if string equals config
function is_config {
	if [ "$1" == "config" ]; then
		return 0
	fi

	return 1
}

# Check if element exists in array
function in_array {
	local e match
	match="$1"
	shift
	for e; do [[ "$e" == "$match" ]] && return 0; done
	return 1
}

# Join array elements by separator
function join {
	local IFS="$1"
	shift
	echo "$*"
}

# Check if graph was requested
function is_requested_graph {
	if [ -z "$1" ] || [ "$1" == "$2" ] ; then
		return 0
	fi

	return 1
}

case $1 in
	autoconf)
		if turbostat_exists; then
			echo "yes"
		else
			echo "no (turbostat command not found)"
		fi
		;;
	suggest)
		if turbostat_exists; then
			echo "watt"
		fi
		;;
	*)
		if ! turbostat_exists; then
			exit 1
		fi

		GRAPH_TYPE=${0##*turbostat_}

		for TYPE in "${SUPPORTED_GRAPH_TYPES[@]}"; do
			if ! is_requested_graph "$GRAPH_TYPE" "$TYPE"; then
				continue
			fi

			emit_multigraph_base "$TYPE"

			case "$TYPE" in
				watt)
					if is_config "$1"; then
						emit_watt_graph
					else
						emit_watt_values
					fi
			esac
		done
		;;
esac