#!/bin/bash
#
# Simple bash script for parsing and evaluating a CSV file
# (C) 2006 Jan Altenberg <tb10alj@tglx.de>
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License Version
# 2 as published by the Free Software Foundation.

GNUPLOT=`which gnuplot`

split_values ()
{
	if [ "$2" = "save_old_state" ]
	then
		OLD_TIME=$TIME
		OLD_CH1=$CH1
		OLD_CH2=$CH2
		TIME=`echo $1 | cut -f1 -d,`
		CH1=`echo $1  | cut -f2 -d,`
		CH2=`echo $1  | cut -f3 -d,`
	else
		TIME=`echo $1 | cut -f1 -d,`
		CH1=`echo $1  | cut -f2 -d,`
		CH2=`echo $1  | cut -f3 -d,`
	fi
}

# We need to convert the TIME value in a format which is readable by bc ;-(
# 1e-04 -> 1 / (10^4)
# 1e+04 -> 1 * (10^4)
convert_time_value ()
{
	VALUE=`echo $1 | sed 's/e-\(.*\)$/\/(10\^\1)/g' | sed 's/e+\(.*\)$/*(10^\1)/'`
	echo $VALUE
}

print_help ()
{
	echo "Usage: $0 -f CSV-file -p PLOT-file"
	echo "  -f CSV-file  (where your data is stored)"
	echo "  -p PLOT-file (where the plot image will be stored)"
}

# Parsing command line options
while getopts "f:p:v" OPTION
do
	case $OPTION in 
		f	) FILE=$OPTARG;;
		p	) PLOT_FILE=$OPTARG;;
		v	) VERBOSE="ON";;
		*	) print_help; exit 1;;
	esac
done

if [ ! "$FILE" ]
then
	print_help
	exit 1
fi

if [ ! -e $FILE ]
then
	echo "Input file does not exist!"
	exit 1
fi

if [ ! "$PLOT_FILE" ]
then
	print_help
	exit 1
fi

if [ ! "$GNUPLOT" ]
then
	echo "Please install gnuplot ! !"
	exit 1
fi

TMPFILE=/tmp/latencies_$$
RESULT_TMPFILE=/tmp/latencies_results_$$

echo "Parsing CSV file..."
echo "  Removing table head..."
cat $FILE | sed '/.*TIME.*/d' > $TMPFILE

echo "  Seperating values..."
for LINE in $(cat $TMPFILE)
do
	if [ ! "$TIME_START" ]
	then
		if [ ! "$TIME" ]
		then
			split_values $LINE
			continue
		else
			split_values $LINE "save_old_state"
			if [ "`echo "scale=2; $CH1 - $OLD_CH1" | bc`" != "0" ]
			then
				TIME_START=`convert_time_value $TIME`
				TIME=""
			else
				continue
			fi
		fi
	else
		split_values $LINE "save_old_state"
		if [ "`echo "scale=2; $CH2 - $OLD_CH2" | bc`" != "0" ]
		then
			TIME_END=`convert_time_value $TIME`
			[ "$VERBOSE" = "ON" ] && echo "    Found latency -> $TIME_END - $TIME_START"
			echo "scale=10; ($TIME_END - $TIME_START)" | bc | sed 's/^\./0\./' >> $RESULT_TMPFILE
			TIME_START=""
			TIME_END=""
			TIME=""
		else
			continue
		fi
	fi
done

echo "Generating plot..."
cat $RESULT_TMPFILE | sort -n | uniq -c | sed 's/^ *//' | sed s'/0*$//'> $TMPFILE
cp $TMPFILE $RESULT_TMPFILE

XMAX=`cat $RESULT_TMPFILE | cut -f2 -d' ' | sort -rn | head -n1`
YMAX=`cat $RESULT_TMPFILE | cut -f1 -d' ' | sort -rn | uniq | head -n1`
XRANGE=`expr "$XMAX * 2"`
YRANGE=`expr "$YMAX * 2"`

echo "  XMAX $XMAX"
echo "  YMAX $YMAX"

echo -e "set title \"Latency test\"\n\
set terminal pbm color\n\
set xrange [0:$XRANGE]\n\
set yrange [0:$YRANGE]\n\
set ylabel\"n\"\n\
set style fill solid 0.250000 border\n\
set output \"$PLOT_FILE\"
plot \"$RESULT_TMPFILE\" using 2:1 \"%lf%lf\" notitle with boxes" | gnuplot -persist

display $PLOT_FILE