#!/bin/bash
#
# Makes thumbnails (a jpeg image) from a given set of input files.
# Supported input file types are those supported by 'convert',
# plus PDF.
# Requires convert(1), gs(1) and file(1)
#
# Usage:      make_thumbs [options] [ file1 file2 ... ]
# Author:     Emiliano Gabrielli
# License:    GPL
# Latest Version at http://SuperAlberT.it/download/command_line_scripts/elog/
#
# $Id: make_thumbs,v 1.7 2005/04/14 10:01:37 albert Exp $

function parse_cmdline()
{
	export OPTERR=1
	while getopts "s:q:Vh" "option" ; do
		case "$option" in
		s)
			MAXSIZE=$OPTARG
			;;
		q)
			QUALITY=$OPTARG
			;;
		V)
			echo "$0 version $VERSION by $AUTHOR"
			exit 1
			;;
		h|*)
			echo -e "\nUsage: make_thumb [options] [ file1 file2 ... ]"
			echo -e "Options:\n"\
			        " -s MAXSIZE  the size of the thumbnail to be created\n"\
			        " -q QUALITY  the quality of the JPEG image created\n"\
				    " -V          print version and exit\n"\
				    " -h          print this help and exit\n"
			exit 1
			;;
		esac
	done
}

function make_thumb()
{
	[ ! -z "$1" ] || exit 1
	FILE="$1"

	# Test if file is readable
	if ! [ -r "$FILE" ] ; then
		echo "ERROR in $0: $FILE is not readable."
		exit 1
	fi
	THUMBFILE="$FILE.thumb"
	EXTENSION="`echo \"$FILE\" | sed 's/.*\.\([^.]*\)$/\1/'`"

	# we need this extension in order to instruct 'convert'
	# will be renamed at the end of the job
	JPEGFILE="$THUMBFILE.jpg"
	ROTATE=""

	# PDF needs special handling
	if [[ `file $FILE | grep "PDF document"` ]] ||
	   [[ `file $FILE | grep "PostScript document"` ]]
	then
	    # look if we should rotate
		DEG=`head -200 $FILE | strings | grep "/Rotate " | head -1 | sed -e 's#.*/Rotate \([0-9]\+\).*#\1#'`
		[ ! -z "$DEG" ] && ROTATE="-rotate $DEG"
		# Extract first page and convert: PDF -> PS -> JPEG (needs 'gs' and 'convert')
		gs -q -dNOPAUSE -dBATCH -r75 -dLastPage=1 -sDEVICE=jpeg -sOutputFile=\|cat "$FILE" | \
		convert - $ROTATE -size ${MAXSIZE}x${MAXSIZE} -resize ${MAXSIZE}x${MAXSIZE} -quality $QUALITY +profile "*" "$JPEGFILE" &&
		mv "$JPEGFILE" "$THUMBFILE" &

	# Else it must be one of the following: postscript, JPEG, GIF, TIFF, RS
	elif [[ `file $FILE | grep "\(JPEG\|GIF\|PNG\|TIFF\) image data"` ]] ||
		 [[ "$EXTENSION" == "rs" ]]   || [[ "$EXTENSION" == "RS" ]]
	then
		convert -size ${MAXSIZE}x${MAXSIZE} "$FILE" -resize ${MAXSIZE}x${MAXSIZE} -quality $QUALITY +profile "*" "$JPEGFILE" &&
		mv "$JPEGFILE" "$THUMBFILE" &
	fi
}


AUTHOR="Emiliano 'AlberT' Gabrielli"
VERSION="0.2.0"
MAXSIZE=600   # default value
QUALITY=70    # default value

parse_cmdline $@
shift `expr $OPTIND - 1`

for file in "$@" ; do
	make_thumb $file
done

# vim:ai:ts=4:sw=4: