#!/bin/bash
# Author: Fernando Luiz Prochnow Ramme, June/30/2015
# Perspective slice plot - vertical perspective to left, version 1.0.0
# INPUT: two or three or four images (PNG format) in the same view scale (width,height) in pixels
# OUTPUT: the combined image in perspective view.
# Developer: Fernando Luiz Prochnow Ramme

# -----------------------------------------------------------------------------------------------------------------------------
# define usage function
function usage
	{
	echo "USAGE: pv-vl.sh OUTFILE INFILE1 INFILE2 [INFILE3] [INFILE4]"
	echo "               OUTFILE: path/filename.extension of output image"
	echo "               INFILE1: path/filename.extension of first input image"
	echo "               INFILE2: path/filename.extension of second input image"
	echo "               INFILE3: optional, path/filename.extension of third input image"
	echo "               INFILE4: optional, path/filename.extension of fourth input image"
	}
#
# -----------------------------------------------------------------------------------------------------------------------------
# function to report error messages, usage and exit
function errMsg
	{
	echo ""
	echo $1
	echo ""
	usage
	exit 1
	}
#
# -----------------------------------------------------------------------------------------------------------------------------
# Apply Perspective View
function processTwoInputs
	{
	echo "Starting..."
	#
	TEMP="/tmp"
	OUTFILE=$1
	OUTFILEF="${OUTFILE%%.*}"
	OUTFILEFN="${OUTFILEF##*/}"
	INFILE1=$2
	INFILE2=$3
	#
	# get Filename without extensions
	INFILE1F="${INFILE1%%.*}"
	INFILE2F="${INFILE2%%.*}"
	#
	# Remove all the prefix until the "/" character
	INFILE1FN="${INFILE1F##*/}"
	INFILE2FN="${INFILE2F##*/}"
	#
	# get Full extensions
	INFILE1E="${INFILE1#*.}"
	INFILE2E="${INFILE2#*.}"
	#
	#saves the absolute path of the current working directory to the variable cwd
	cwd="`dirname ${BASH_SOURCE[0]}`"
	#echo "$cwd"
	#
	# Apply Perspective View - vertical perspective to left
        OUTFILE1TMP=$INFILE1FN"_out."$INFILE1E
        OUTFILE2TMP=$INFILE2FN"_out."$INFILE2E
	$cwd/perspective.sh 125,0,0 $INFILE1 $OUTFILE1TMP
	# only processing second file if different from first filename
	if [ $OUTFILE1TMP != $OUTFILE2TMP ]
		then
		$cwd/perspective.sh 125,0,0 $INFILE2 $OUTFILE2TMP
	fi
	#
	# Combine images and generate OUTPUT image
	convert \( $OUTFILE1TMP -set colorspace sRGB $cwd/gray240.png $OUTFILE2TMP $cwd/gray240.png -gravity center -background 'rgb(240,240,240)' +append \) \
			-background white -gravity center -set colorspace sRGB -append $OUTFILE
	#
	# Convert OUTPUT image to PDF
	#convert -quality 100 -compress Zip $OUTFILE $OUTFILE.pdf
	#remove fist temporary file
	rm $OUTFILE1TMP
	# only remove second temporary file if created in the processing
	if [ $OUTFILE1TMP != $OUTFILE2TMP ]
		then
		rm $OUTFILE2TMP
	fi
	}
#
# -----------------------------------------------------------------------------------------------------------------------------
# Apply Perspective View
function processThreeInputs
	{
	echo "Starting..."
	#
	TEMP="/tmp"
	OUTFILE=$1
	OUTFILEF="${OUTFILE%%.*}"
	OUTFILEFN="${OUTFILEF##*/}"
	INFILE1=$2
	INFILE2=$3
	INFILE3=$4
	#
	# get Filename without extensions
	INFILE1F="${INFILE1%%.*}"
	INFILE2F="${INFILE2%%.*}"
	INFILE3F="${INFILE3%%.*}"
	#
	# Remove all the prefix until the "/" character
	INFILE1FN="${INFILE1F##*/}"
	INFILE2FN="${INFILE2F##*/}"
	INFILE3FN="${INFILE3F##*/}"
	#
	# get Full extensions
	INFILE1E="${INFILE1#*.}"
	INFILE2E="${INFILE2#*.}"
	INFILE3E="${INFILE3#*.}"
	#
	#saves the absolute path of the current working directory to the variable cwd
	cwd="`dirname ${BASH_SOURCE[0]}`"
	#echo "$cwd"
	#
	# Apply Perspective View - vertical perspective to left
        OUTFILE1TMP=$INFILE1FN"_out."$INFILE1E
        OUTFILE2TMP=$INFILE2FN"_out."$INFILE2E
        OUTFILE3TMP=$INFILE3FN"_out."$INFILE3E
	$cwd/perspective.sh 125,0,0 $INFILE1 $OUTFILE1TMP
	# only processing second file if different from first filename
	if [ $OUTFILE2TMP != $OUTFILE1TMP ]
		then
		$cwd/perspective.sh 125,0,0 $INFILE2 $OUTFILE2TMP
	fi
	# only processing third file if different from first filename
	if [ $OUTFILE3TMP != $OUTFILE1TMP ]
		then
		$cwd/perspective.sh 125,0,0 $INFILE3 $OUTFILE3TMP
	fi
	#
	# Combine images and generate OUTPUT image
	convert \( $OUTFILE1TMP -set colorspace sRGB $cwd/gray240.png $OUTFILE2TMP $cwd/gray240.png $OUTFILE3TMP $cwd/gray240.png -gravity center -background 'rgb(240,240,240)' +append \) \
			-background white -gravity center -set colorspace sRGB -append $OUTFILE
	#
	# Convert OUTPUT image to PDF
	#convert -quality 100 -compress Zip $OUTFILE $OUTFILE.pdf
	#
	# CLEAN temporary files
	#remove fist temporary file
	rm $OUTFILE1TMP
	# only remove second temporary file if created in the processing
	if [ $OUTFILE2TMP != $OUTFILE1TMP ]
		then
		rm $OUTFILE2TMP
	fi
	# only remove third temporary file if created in the processing
	if [ $OUTFILE3TMP != $OUTFILE1TMP ]
		then
		rm $OUTFILE3TMP
	fi
	}
#
# -----------------------------------------------------------------------------------------------------------------------------
# Apply Perspective View
function processFourInputs
	{
	echo "Starting..."
	#
	TEMP="/tmp"
	OUTFILE=$1
	OUTFILEF="${OUTFILE%%.*}"
	OUTFILEFN="${OUTFILEF##*/}"
	INFILE1=$2
	INFILE2=$3
	INFILE3=$4
	INFILE4=$5
	#
	# get Filename without extensions
	INFILE1F="${INFILE1%%.*}"
	INFILE2F="${INFILE2%%.*}"
	INFILE3F="${INFILE3%%.*}"
	INFILE4F="${INFILE4%%.*}"
	#
	# Remove all the prefix until the "/" character
	INFILE1FN="${INFILE1F##*/}"
	INFILE2FN="${INFILE2F##*/}"
	INFILE3FN="${INFILE3F##*/}"
	INFILE4FN="${INFILE4F##*/}"
	#
	# get Full extensions
	INFILE1E="${INFILE1#*.}"
	INFILE2E="${INFILE2#*.}"
	INFILE3E="${INFILE3#*.}"
	INFILE4E="${INFILE4#*.}"
	#
	#saves the absolute path of the current working directory to the variable cwd
	cwd="`dirname ${BASH_SOURCE[0]}`"
	#echo "$cwd"
	#
	# Apply Perspective View - vertical perspective to left
        OUTFILE1TMP=$INFILE1FN"_out."$INFILE1E
        OUTFILE2TMP=$INFILE2FN"_out."$INFILE2E
        OUTFILE3TMP=$INFILE3FN"_out."$INFILE3E
        OUTFILE4TMP=$INFILE4FN"_out."$INFILE4E
	$cwd/perspective.sh 125,0,0 $INFILE1 $OUTFILE1TMP
	# only processing second file if different from first filename
	if [ $OUTFILE2TMP != $OUTFILE1TMP ]
		then
		$cwd/perspective.sh 125,0,0 $INFILE2 $OUTFILE2TMP
	fi
	# only processing third file if different from first filename
	if [ $OUTFILE3TMP != $OUTFILE1TMP ]
		then
		$cwd/perspective.sh 125,0,0 $INFILE3 $OUTFILE3TMP
	fi
	# only processing fourth file if different from first filename
	if [ $OUTFILE4TMP != $OUTFILE1TMP ]
		then
		$cwd/perspective.sh 125,0,0 $INFILE4 $OUTFILE4TMP
	fi
	#
	# Combine images and generate OUTPUT image
	convert \( $OUTFILE1TMP -set colorspace sRGB $cwd/gray240.png $OUTFILE2TMP $cwd/gray240.png $OUTFILE3TMP $cwd/gray240.png $OUTFILE4TMP $cwd/gray240.png -gravity center -background 'rgb(240,240,240)' +append \) \
			-background white -gravity center -set colorspace sRGB -append $OUTFILE
	#
	# Convert OUTPUT image to PDF
	#convert -quality 100 -compress Zip $OUTFILE $OUTFILE.pdf
	#
	# CLEAN temporary files
	#remove fist temporary file
	rm $OUTFILE1TMP
	# only remove second temporary file if created in the processing
	if [ $OUTFILE2TMP != $OUTFILE1TMP ]
		then
		rm $OUTFILE2TMP
	fi
	# only remove third temporary file if created in the processing
	if [ $OUTFILE3TMP != $OUTFILE1TMP ]
		then
		rm $OUTFILE3TMP
	fi
	# only remove fourth temporary file if created in the processing
	if [ $OUTFILE4TMP != $OUTFILE1TMP ]
		then
		rm $OUTFILE4TMP
	fi
	}
#
# -----------------------------------------------------------------------------------------------------------------------------
# INITIALIZATION
#
# test for correct number of arguments and get values
if [ $# -eq 0 ]
	then
	# help information
	usage
	exit 0
elif [ $# -lt 3 ]
	then
	errMsg "--- NO PARAMETER VALUES WERE PROVIDED ---"	
elif [ $# -eq 3 ]
	then
	echo "processing INPUT1 and INPUT2"
	processTwoInputs $1 $2 $3
elif [ $# -eq 4 ]
	then
	echo "processing INPUT1 INPUT2 INPUT3"
	processThreeInputs $1 $2 $3 $4
elif [ $# -eq 5 ]
	then
	echo "processing INPUT1 INPUT2 INPUT 3 INPUT4"
	processFourInputs $1 $2 $3 $4 $5
elif [ $# -gt 5 ]
	then
	usage
	exit 0
fi

# -----------------------------------------------------------------------------------------------------------------------------