#!/bin/bash

# get read-only API key from http://EM.ON.CMS.IP/emoncms/feed/api
# put read-only API key below 
APIKEY=abc123_PUT_YOUR_API_KEY_HERE_abc123

# get feed id from http://EM.ON.CMS.IP/emoncms/feed/list
# put feed id below
feed_temp=15
feed_pwr1=1
feed_pwr2=17

WATCHDOG_LIMIT=300 # 5 minutes

###########################################
### NO CHANGES REQUIRED BELOW THIS LINE ###
###########################################
LOGDIR=/home/pi/watchlog
TRIGGER=/tmp/watchdog-triggered

###
### save logfiles and relevant debug information
###
function watchdog_log {
	now=$(date '+%s')
	timestamp=$(date +%Y%m%d-%H%M%S%z -d@$now)

	# create trigger file to indicate watchdog has been triggered
	touch $TRIGGER

	rpi-rw >/dev/null

	# make sure the LOGDIR exists
	mkdir -p $LOGDIR/$timestamp/
	
	# write collected data
	file=$LOGDIR/$timestamp/data.txt
	date +%s > $file
	echo $output_temp >> $file
	echo $output_pwr1 >> $file
	echo $output_pwr2 >> $file

	# make a copy of log files
	cp -prv /var/log/syslog $LOGDIR/$timestamp/
	cp -prv /var/log/emoncms.log $LOGDIR/$timestamp/

	# save output of multiple commands
	ps -AHf > $LOGDIR/$timestamp/cmd-ps.txt
	service --status-all 2>&1 > $LOGDIR/$timestamp/cmd-service.txt
	top -bn1 > $LOGDIR/$timestamp/cmd-top.txt
	
	# create a tar archive for easy upload to https://community.openenergymonitor.org forum
	TARFILE=$LOGDIR/watchdog-$timestamp.tar.gz
	tar -czvf $TARFILE $LOGDIR/$timestamp
	
	ls -l $LOGDIR/$timestamp/
	echo
	echo "You can now upload $TARFILE to the forum"
	echo "Alternatively, upload specific files from $LOGDIR/$timestamp/"

	rpi-ro >/dev/null
}

###
### probe EmonCMS API and, if needed, collect logs
###
function watchdog_probe {
	###
	### COLLECT data from EmonCMS
	###
	output_temp=`wget -qO- "http://127.0.0.1/emoncms/feed/timevalue.json?id=${feed_temp}&apikey=$APIKEY"`
	output_pwr1=`wget -qO- "http://127.0.0.1/emoncms/feed/timevalue.json?id=${feed_pwr1}&apikey=$APIKEY"`
	output_pwr2=`wget -qO- "http://127.0.0.1/emoncms/feed/timevalue.json?id=${feed_pwr2}&apikey=$APIKEY"`


	###
	### EVALUATE the measurements and take action if needed
	###
	now=`date +%s`

	# get time of feed
	time_temp=$(echo $output_temp | sed 's/.*"time":\([^,]*\).*/\1/')
	time_pwr1=$(echo $output_pwr1 | sed 's/.*"time":\([^,]*\).*/\1/')
	time_pwr2=$(echo $output_pwr2 | sed 's/.*"time":\([^,]*\).*/\1/')

	# calculate difference between last measurement and current timestamp
	diff_temp=$(($now-$time_temp))
	diff_pwr1=$(($now-$time_pwr1))
	diff_pwr2=$(($now-$time_pwr2))

	# $WATCHDOG_LIMIT stayalive timer exceeded?
	if [ $diff_temp -gt $WATCHDOG_LIMIT ] || [ $diff_pwr1 -gt $WATCHDOG_LIMIT ] || [ $diff_pwr2 -gt $WATCHDOG_LIMIT ]; then
		# if the trigger file already exists, don't trigger the watchdog anymore
		if [ -f $TRIGGER ]; then
			echo "Watchdog detected anomaly but it was triggered before. Not collecting logs again." | logger -it watchdog
			exit 0
		fi
		echo "Watchdog detected anomaly and was not triggered before. Collecting logs." | logger -it watchdog
		watchdog_log
		#sudo reboot
		exit 0
	fi
}

###
### check if CRON calls the watchdog
###
function watchdog_status {
	crontab -l | grep watchdog
}
###
### install in CRON (requires rpi-rw, run as sudo)
###
function watchdog_install {
	crontab -l | grep watchdog
	if [ $? -ne 0 ]; then
		echo '*/1 * * * * /home/pi/watchdog.sh' | tee -a /var/spool/cron/crontabs/pi
		crontab -l | grep watchdog
	fi
}
###
### uninstall from CRON (requires rpi-rw, run as sudo)
###
function watchdog_uninstall {
	awk '! /.*watchdog.sh$/' /var/spool/cron/crontabs/pi > /var/spool/cron/crontabs/pi
}

#grep ^PPid /proc/$$/status | sed 's/.*:[ \t]*\([0-9]*\)/\1/'
#PPID=`ps -p $$ -o ppid=`
PCOM=`ps -p $PPID -o comm=`
if [ "$PCOM" == "bash" ]; then
	echo 'called from bash. Just collecting logs.'
	watchdog_log
else
	#echo 'called from ['$PPID'] '$PCOM > /tmp/watchdog
	#ps -AHf > /tmp/watchps
	watchdog_probe
fi