#!/bin/sh
# Copyright (C) 2007 Adalbert Prokop, adalbert.prokop(%)web.de

# 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 St, Fifth Floor, Boston, MA  02110-1301  USA

# Last change: 2007-07-29

#set -x #debug
LOGODIR=with_logo
LOGOIMG="$(mktemp)"
LOGOMASK="$(mktemp)"
LOGOFILE=
OPACITY=0.5
LOGOSDIR=$HOME/homepage-src/logos

function usage() {
	cat >&2 <<EOF
Usage:
$(basename $0) {-l|--logo} logofile [{-x|--xsize} width] [{-y|--ysize} height]
	[{-t|--text} text] [{-o|--opacity} opacity] [-f|--force] [files...]

Inserts the give logo as an (possibly translucent) PNG image into a JPEG image.
If there are no JPEG images given, this script will work as an PNM filter on
standard input.

Options:
--cXXX
Default copyright note in XXX resolution

--XXX
Default note (without ©) in XXX resolution

-f, --force
Force overwriting.

-l, --logo
This is the logo file which will be pasted over the image. You must specify
this.

-o, --opacity
Opacity of the logo. A value of 1.0 will make your logo completely opaq and a
value of 0.0 will make it completely translucent.
Default is $OPACITY

-t, --text
A text which will be inserted into the JPEG comment block. Does not work in
filter mode.

-x, --xsize
-y, --ysize
The output image will be resized to this measures. If you give only one
argument (either width or height) the other dimension will be scaled to
preserve the aspect ratio. Default is no resizing.
EOF
}

# parse command line args
eval set -- $(getopt -o fl:o:t:x:y: -l force,logo:,xsize:,ysize:,text:,opacity:,c100,c200,c400,c600,c800,100,200,400,600,800,mg200,mg400,mg600,mg800 -- "$@")
if [ "$?" -ne 0 ]; then
	usage
	echo "Exiting because of previous errors." >&2
	exit 1
fi

while [ "$1" != "--" ]; do
	case "$1" in
		-l|--logo)
			LOGOFILE="$2"
			shift 2
			;;
		-x|--xsize)
			XSIZE="$2"
			shift 2
			;;
		-y|--ysize)
			YSIZE="$2"
			shift 2
			;;
		-t|--text)
			TEXT="$2"
			shift 2
			;;
		-o|--opacity)
			OPACITY="$2"
			shift 2
			;;
		-f|--force)
			FORCEOVERWRITING=1
			shift
			;;
		--c?00)
			LOGOFILE=$LOGOSDIR/familie-prokop_c-${1#--c}.png
			TEXT="(C) http://www.familie-prokop.de/"
			shift
			;;
		--?00)
			LOGOFILE=$LOGOSDIR/familie-prokop-${1#--}.png
			TEXT="from http://www.familie-prokop.de/"
			shift
			;;
		--mg?00)
			LOGOFILE=$LOGOSDIR/mg-${1#--mg}.png
			TEXT="http://www.mojageneracja.pl/6414902/"
			shift
			;;
		*)
			echo "Unknown option $1. (You shouldn't be here!)"
			exit 1
			;;
	esac
done
shift # get rid of "--"

if [ ! -f "$LOGOFILE" ]; then
	echo "You have to specify a logo file."
	usage
	exit 1
fi

if [ -n "$XSIZE" -a -n "$YSIZE" ]; then
	RESIZECMD="pnmscale -xysize $XSIZE $YSIZE"
elif [ -n "$XSIZE" ]; then
	RESIZECMD="pnmscale -xsize $XSIZE"
elif [ -n "$YSIZE" ]; then
	RESIZECMD="pnmscale -ysize $YSIZE"
else
	RESIZECMD=cat
fi

pngtopnm "$LOGOFILE" > "$LOGOIMG"
RETVAL=$?
if [ $RETVAL -ne 0 ]; then
	echo "Logofile cannot be read" >&2
	exit 1
fi
pngtopnm -alpha "$LOGOFILE" > "$LOGOMASK"

if [ "$#" -gt 0 ]; then # we have some files to work on
	mkdir -p "$LOGODIR"
	for file in "$@"; do
		if [ ! -f  "$file" ]; then
			echo "File $file does not exist. Skipping."
			continue
		fi
		echo -n "Inserting $LOGOFILE into $file... "
		if [ -f "$LOGODIR/$file" -a -z "$FORCEOVERWRITING" ]; then
			echo
			echo "$LOGODIR/$file exists, won't overwrite" >&2
			continue
		fi
		djpeg "$file" | $RESIZECMD | pamcomp -xoff 1 -yoff -1 -opacity="$OPACITY" -valign=bottom -alpha "$LOGOMASK" "$LOGOIMG" | cjpeg -opt -pro > "$LOGODIR/$file"
		if [ -s "$LOGODIR/$file" ]; then
			jhead ${TEXT:+-cl "$TEXT"} -te "$file" "$LOGODIR/$file" > /dev/null
			touch -r "$file" "$LOGODIR/$file"
		else
			rm -f "$LOGODIR/$file"
		fi
		echo "done."
	done
	rmdir with_logo >& /dev/null
else # we have no files. in this case we work as an PNM-Filter
	$RESIZECMD | pamcomp -xoff 1 -yoff -1 -opacity="$OPACITY" -valign=bottom -alpha "$LOGOMASK" "$LOGOIMG"
fi

rm -f "$LOGOIMG" "$LOGOMASK"