#! /bin/bash
# average the PRESENT_POWER_READING values that are in a log file

count=0
sum=0

cat logs/getpower.log | while read line ; do
	if [ "${line:0:29}" != "<PRESENT_POWER_READING VALUE=" ]; then
		continue
	fi
	value=${line:29}
	##echo "value0:$value"
	value=`echo $value | tr -d \\"/\\>`
	##echo "value1:$value"
	len=${#value}
	##echo "len=$len"
	if [ ${value:$((len - 11)):10} != "UNIT=Watts" ]; then
		echo "UNIT not in Watts, ignored: $value"
		continue
	fi
	value=${value:0:$((len - 11))}
	##echo "value2:$value:"
	len=${#value}
	##echo "len2=$len"
	if [ "${value:$((len - 1)):1}" == " " ]; then
		value=${value:0:$((len - 1))}
	fi
	echo "value3:$value:"
	##count=`expr $count + 1`

	count=$((count++))
	sum=$((sum + value))
done

echo "count: $count, sum: $sum"