#!/usr/bin/env python

import os
import re
from vendor.munin import MuninPlugin

class CPUPlugin(MuninPlugin):
    title = "CPU usage"
    args = "--base 1000 -r --lower-limit 0 --upper-limit 100" #" --upper-limit $graphlimit"
    vlabel = "%"
    category = "system"
    period = "second" # TODO: I think this is the default anyway
    info = "This graph shows how CPU time is spent."

    @property
    def order(self):
        return ("system user nice idle " + self.extinfo).strip()

    @property
    def extinfo(self):
        if hasattr(self, '_extinfo'):
           return self._extinfo

        fp = open("/proc/stat", "rb")
        stat = fp.read()
        fp.close()
        if bool(re.match(r"^cpu +[0-9]+ +[0-9]+ +[0-9]+ +[0-9]+ +[0-9]+ +[0-9]+ +[0-9]+", stat)):
            self._extinfo = "iowait irq softirq"
        else:
            self._extinfo = ""

        return self._extinfo

    @property
    def fields(self):
        warning = os.environ.get('load_warn', 10)
        critical = os.environ.get('load_crit', 120)
        fields = [
            ("system", dict(
                label = "system"
                draw = "AREA",
                max = max,
                min = min,
                type = "DERIVE",
                warning = syswarning,
                critical = syscritical,
                info = "CPU time spent by the kernel in system activities",
            )),
            ("user", dict(
                label = "user"
                draw = "STACK",
                max = max,
                min = "0",
                type = "DERIVE",
                warning = usrwarning,
                info = "CPU time spent by normal programs and daemons",
            ))
        ]
        return [("load", dict(
                label = "load",
                info = 'The load average of the machine describes how many processes are in the run-queue (scheduled to run "immediately").',
                type = "GAUGE",
                min = "0",
                warning = str(warning),
                critical = str(critical)))]

    def execute(self):
        if os.path.exists("/proc/loadavg"):
            loadavg = open("/proc/loadavg", "r").read().strip().split(' ')
        else:
            from subprocess import Popen, PIPE
            output = Popen(["uptime"], stdout=PIPE).communicate()[0]
            loadavg = output.rsplit(':', 1)[1].strip().split(' ')[:3]
            print loadavg
        print "load.value %s" % loadavg[1]

if __name__ == "__main__":
    CPUPlugin().run()

if (`egrep '^cpu +[0-9]+ +[0-9]+ +[0-9]+ +[0-9]+ +[0-9]+ +[0-9]+ +[0-9]+' /proc/stat 2>/dev/null >/dev/null`)
then
	extinfo="iowait irq softirq"
fi

if [ "$1" = "config" ]; then

	NCPU=$(egrep '^cpu[0-9]+ ' /proc/stat | wc -l)
	PERCENT=$(($NCPU * 100))
	MAX=$(($NCPU * 100))
	if [ "$scaleto100" = "yes" ]; then
		graphlimit=100
	else
		graphlimit=$PERCENT
	fi
	SYSWARNING=`expr $PERCENT '*' 30 / 100`
	SYSCRITICAL=`expr $PERCENT '*' 50 / 100`
	USRWARNING=`expr $PERCENT '*' 80 / 100`
	echo 'nice.label nice'
	echo 'nice.draw STACK'
	echo 'nice.min 0'
	echo "nice.max $MAX"
	echo 'nice.type DERIVE'
	echo 'nice.info CPU time spent by nice(1)d programs'
	echo 'idle.label idle'
	echo 'idle.draw STACK'
	echo 'idle.min 0'
	echo "idle.max $MAX"
	echo 'idle.type DERIVE'
	echo 'idle.info Idle CPU time'
	if [ "$scaleto100" = "yes" ]; then
		echo "system.cdef system,$NCPU,/"
		echo "user.cdef user,$NCPU,/"
		echo "nice.cdef nice,$NCPU,/"
		echo "idle.cdef idle,$NCPU,/"
	fi
	if [ ! -z "$extinfo" ]
	then
		echo 'iowait.label iowait'
		echo 'iowait.draw STACK'
		echo 'iowait.min 0'
		echo "iowait.max $MAX"
		echo 'iowait.type DERIVE'
		echo 'iowait.info CPU time spent waiting for I/O operations to finish'
		echo 'irq.label irq'
		echo 'irq.draw STACK'
		echo 'irq.min 0'
		echo "irq.max $MAX"
		echo 'irq.type DERIVE'
		echo 'irq.info CPU time spent handling interrupts'
		echo 'softirq.label softirq'
		echo 'softirq.draw STACK'
		echo 'softirq.min 0'
		echo "softirq.max $MAX"
		echo 'softirq.type DERIVE'
		echo 'softirq.info CPU time spent handling "batched" interrupts'
		if [ "$scaleto100" = "yes" ]; then
			echo "iowait.cdef iowait,$NCPU,/"
			echo "irq.cdef irq,$NCPU,/"
			echo "softirq.cdef softirq,$NCPU,/"
		fi
	fi
	exit 0
fi

HZ=`getconf CLK_TCK`

if [ ! -z "$extinfo" ]
then
	awk -v HZ=$HZ 'BEGIN { factor=100/HZ } /^cpu / { for (i=2; i<=8; i++) { $i = int($i * factor) }; print "user.value " $2 "\nnice.value " $3 "\nsystem.value " $4 "\nidle.value " $5 "\niowait.value " $6 "\nirq.value " $7 "\nsoftirq.value " $8 }' < /proc/stat

else
	awk -v HZ=$HZ 'BEGIN { factor=100/HZ } /^cpu / { for (i=2; i<=5; i++) { $i = int($i * factor) }; print "user.value " $2 "\nnice.value " $3 "\nsystem.value " $4 "\nidle.value " $5 }' < /proc/stat
fi