#/bin/bash -x

usage() {
    echo "Depends on: xpdf-utils, xpdf-reader, netpbm and djvulibre-bin " 2>&1
    echo "Usage: $(basename $0) [-f first_page] [-l last_page] [-r90|-r180|-r270] [-d dpi] input.pdf output.djvu" 2>&1
    echo "Whether it results in different size pages force resolution (-d)" 2>&1
}

while getopts "r:f:l:d:" flag; do
    case "$flag" in
      r)
	case "$OPTARG" in
	  90)  FLIPOPT=-rotate90;;
	  180) FLIPOPT=-rotate180;;
	  270) FLIPOPT=-rotate270;;
	  *)   usage; echo "Option -r incorrect" 1>&2; exit;;
	esac;;
      f) PDFOPT="$PDFOPT -f $OPTARG";;
      l) PDFOPT="$PDFOPT -l $OPTARG";;
      d) RESOPT="-r $OPTARG";;
      *) usage; exit;;
    esac
done
shift $((OPTIND - 1))

if [[ $# != 2 ]]; then
    usage; exit
fi

INPUT="$1"
OUTPUT="$2"

TMPDIR=$(mktemp -t -d pms2d.XXXXXXXXXX)
trap "rm -rf \"$TMPDIR\"; exit" INT TERM EXIT

if [[ -n "$RESOPT" ]]; then
    pdftoppm $PDFOPT $RESOPT -mono "$INPUT" "$TMPDIR"/img
else
    pdfimages $PDFOPT "$INPUT" "$TMPDIR"/img
fi
for img in $(ls "$TMPDIR"/img*.pbm); do
    if [[ ! -z $FLIPOPT ]]; then
	pnmflip $FLIPOPT "$img" > "$TMPDIR"/tmp
	mv "$TMPDIR"/tmp "$img"
    fi

    cjb2 "$img" "$TMPDIR"/$(basename "$img" .pbm).djvu
    rm "$img"
done
djvm -c "$OUTPUT" "$TMPDIR"/*.djvu