#!/bin/bash

# Copyright (C) 2008 Richard G. Heck, Jr.

# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

# Updates etc should be available from:
# http://frege.brown.edu/heck/linux/programs/bash.php

# Change log

# Version 0.1: First public release

# TODO
# Implement losslevel
# convert input files to bitonal

PROG=`basename $0`;

function printUsage {
cat <<EOF
USAGE: $PROG [-abcdefhklpqrR] PREFIX
$PROG takes a set of tiff images---say, scans of pages---and creates a 
DJVU file from them. It will also create a PDF, if requested. PREFIX is the
prefix of files to use: We'll convert PREFIX*.tiff.

Input files must be bitonal.

Options:
-a: Make a PDF, too.
-A: Also make a PDF with split pages.
-b: Batch mode: Make a separate file for each page.
-c: Crop both first and last page.
-C: Crop all pages to WxH+X+Y (as ImageMagick).
    Note that this is done before rotation, if rotation is done.
-d: Don't do anything, just say what we'd do.
-D: Don't create DJVU.
-f: Crop top half of first page.
-h: Print this message.
-k: Keep intermediate files.
-l: Crop bottom half of last page.
-q: Be quiet.
-r: Rotate pages ARG degrees.
-R: Don't rotate pages.

Prerequisite:
- We use convert, from ImageMagick, for page manipulation.
EOF
}

function crop {
	FILE=$1;
	SIDE=$2;
	if [ -z "$SIDE" ]; then
		echo "Function crop must be given three arguments.";
		exit 1;
	fi

	# get image size data, and figure out how to crop
	DATA=`identify $FILE | cut -d' ' -f 3`;
	WIDTH=${DATA%x*};
	HEIGHT=${DATA#*x};
	NEWHT=$(($HEIGHT / 2));
	NEWDT=$(($WIDTH / 2));
	if [ "$SIDE" = "N" ]; then
		RECT="0,0 $WIDTH,$NEWHT";
	elif [ "$SIDE" = "S" ]; then
		RECT="0,$NEWHT $WIDTH,$HEIGHT";
	elif [ "$SIDE" = "W" ]; then
		RECT="0,0 $NEWDT,$HEIGHT";
	elif [ "$SIDE" = "E" ]; then
		RECT="$NEWDT,0 $WIDTH,$HEIGHT";
	else
		echo "Missing directional argument in crop()";
		exit 1;
	fi

	TMP=$FILE.$$.tiff;
	cp $FILE $TMP;
	# crop it
	#$DEBUG convert $TMP -fill white -draw "rectangle $RECT" -type Bilevel -colors 2 -threshold 127,127,127 $FILE;
	$DEBUG convert $TMP -fill white -draw "rectangle $RECT" -type Grayscale $FILE;
}


DEBUG="";

BATCH="";
PDF="";
EXT="tiff"; # this could be generalized, but it can lead to problems
            # with cropping, because the djvu programs expect the files
            # in a very particular format.
KEEP="";
QUIET="";
ROTATE="270";
MKDJVU="YES";
CROPFIRST="";
CROPLAST="";
CROPDIMS="";

while getopts ":aAbcC:dDfklqr:R" opt; do
	case $opt in
		a )   PDF="YES";;
		A )   PDFSPLIT="YES";;
		b )   BATCH="YES";;
		c )   CROPFIRST="TRUE"; CROPLAST="TRUE";;
		C )   CROPDIMS="$OPTARG";;
		d )   DEBUG="echo ";;
		D )   MKDJVU="";;
		f )   CROPFIRST="TRUE";;
		k )   KEEP="echo ";;
		l )   CROPLAST="TRUE";;
		q )   QUIET="TRUE";;
		r )   ROTATE="$OPTARG";;
		R )   ROTATE="";;
		\? )  printUsage; exit 1;;
	esac
done

shift $(($OPTIND - 1));

CVT=`which convert 2>/dev/null`;
if [ -z "$CVT" ]; then 
	echo "This script uses the convert utility from the ImageMagick package. It does not appear to be in your path.";
	exit 1;
fi

# Get filename we're looking for
if [ -n "$1" ]; then
	FILENAME="$1";
else
	FILENAME="pages";
fi

OLDFILES=$(ls -1 $FILENAME*.$EXT 2>/dev/null);
if [ -z "$OLDFILES" ]; then
	echo "No files found matching $FILENAME*.$EXT";
	exit 1;
fi

FIRSTFILE="";
LASTFILE="";
FILES="";
echo "Copying original files";
for fil in $OLDFILES; do
	echo -n ".";
	NEWFILE="tiff2djvu-$$-$fil";
	$DEBUG cp $fil $NEWFILE;
	if [ -z "$FILES" ]; then 
		FILES="$NEWFILE"; 
	else
		FILES="$FILES
$NEWFILE";
	fi
	if [ -z "$FIRSTFILE" ]; then FIRSTFILE="$NEWFILE"; fi;
	LASTFILE="$NEWFILE";
done
echo "done.";

# Crop pages if requested
if [ -n "$CROPDIMS" ]; then
	echo "Cropping to $CROPDIMS";
	for fil in $FILES; do
		echo -n ".";
		CFIL="precrop-$fil";
		if [ -z "$DEBUG" ]; then mv $fil $CFIL; fi
		$DEBUG convert $CFIL -crop $CROPDIMS +repage $fil;
		$DEBUG $KEEP rm $CFIL;
	done
	echo "done.";
fi

# Rotate pages if requested
if [ -n "$ROTATE" ]; then
	echo "Rotating pages";
	for fil in $FILES; do
		echo -n ".";
		RFIL="prerot-$fil";
		if [ -z "$DEBUG" ]; then mv $fil $RFIL; fi
		$DEBUG convert -rotate $ROTATE $RFIL $fil;
		$DEBUG $KEEP rm $RFIL;
	done
	echo "done.";
fi

# Crop first and last pages if requested
if [ -n "$CROPFIRST$CROPLAST" ]; then
	echo -n "Cropping";
	if [ -n "$CROPFIRST" ]; then 
		echo -n " first page";
		crop $FIRSTFILE "W";
	fi
	if [ -n "$CROPLAST" ]; then
		if [ -n "$CROPFIRST" ]; then echo -n " and"; fi
		if [ -z "$QUIET" ]; then echo " last page."; fi
		crop $LASTFILE "E";
	else
		echo ".";
	fi
fi

echo "Converting";
for i in $FILES; do 
	echo -n ".";
	if [ -n "$MKDJVU" ]; then
		DJVUFIL="djvu-$$-$i";
		if identify $i | grep -q Bilevel; then
			ln -s $i $DJVUFIL;
		else
			$DEBUG convert $i -depth 1 $DJVUFIL;
		fi
		$DEBUG cjb2 $DJVUFIL ${i%$EXT}djvu; 
		$DEBUG $KEEP rm $DJVUFIL;
	fi

	if [ -n "$PDF" ]; then
		PNGFIL="${i%$EXT}png";
		PDFFIL="${i%$EXT}pdf";
		$DEBUG convert $i -resize ${NEWDT}x$NEWHT +repage -type Grayscale -depth 4 +compress $PNGFIL;
		if [ -n "$BATCH" ]; then
			$DEBUG convert $PNGFIL $PDFFIL;
			$DEBUG $KEEP rm $PNGFIL;
		fi
	fi

	if [ -n "$PDFSPLIT" ]; then
		DATA=`identify $i | cut -d' ' -f 3`;
		WIDTH=${DATA%x*};
		HEIGHT=${DATA#*x};
		NEWDT=$(($WIDTH / 2));
		NEWHT=$(($HEIGHT / 2));
		if [ "$i" != "$FIRSTFILE" -o -z "$CROPFIRST" ]; then
			#$DEBUG convert $i -resize ${NEWDT}x$NEWHT +repage -type Grayscale +compress $i;
			#NEWDT=$(($NEWDT / 2));
			$DEBUG convert $i -crop ${NEWDT}x$HEIGHT+0+0 +repage -type Grayscale -depth 4 +compress SPLIT-$$-$i.1.png;
		fi
		if [ "$i" != "$LASTFILE" -o -z "$CROPLAST" ]; then
			#$DEBUG convert $i -resize ${NEWDT}x$NEWHT +repage -type Grayscale +compress $i;
			#NEWDT=$(($NEWDT / 2));
			$DEBUG convert $i -crop ${NEWDT}x$HEIGHT+${NEWDT}+0 +repage -type Grayscale -depth 4 +compress SPLIT-$$-$i.2.png;
		fi
	fi
done
echo "done.";

if [ -z "$BATCH" ]; then
	if [ -n "$MKDJVU" ]; then
		echo "Creating DJVU.";
		$DEBUG djvm -c x$FILENAME.djvu tiff2djvu-$$-$FILENAME*djvu;
		rm tiff2djvu-$$-$FILENAME*djvu;
		mv x$FILENAME.djvu $FILENAME.djvu
	fi
	if [ -n "$PDF" ]; then
		echo "Creating PDF.";
		$DEBUG convert $FILENAME*png $FILENAME.pdf
		$DEBUG $KEEP rm $FILENAME*tiff;
	fi
	if [ -n "$PDFSPLIT" ]; then
		echo "Creating single-page PDF.";
		if [ -z "$PDF" ]; then 
			PDFNAME=$FILENAME.pdf; 
		else 
			PDFNAME=$FILENAME-split.pdf;
		fi
		$DEBUG convert SPLIT-$$-*.png $PDFNAME;
		$DEBUG $KEEP rm SPLIT-$$-*.png;
	fi
fi

$DEBUG $KEEP rm tiff2djvu-$$-$FILENAME*.tiff;