Removes annoying watermark links from it-ebooks pdfs

unwatermark.sh

#!/usr/bin/env bash
set -euf -o pipefail
# Usage
# ./unwatermark.sh it-ebooks.info sharefactory.com somefile.pdf

TARGET_PDF=${@: -1}
TARGET_PATH=$(dirname $TARGET_PDF)
BACKUP_PDF=$(echo $TARGET_PDF | sed "s/.pdf$/.pdf.bak/g")
TMP_PDF=$TARGET_PDF.tmp
NEEDLES=${@:1:$(($#-1))}

if [[ ! -f $TARGET_PDF ]]; then
    echo 'bad file'
    exit 1
fi

cp -pr $TARGET_PDF $TMP_PDF
cp -pr $TARGET_PDF $BACKUP_PDF
for NEEDLE in $NEEDLES; do
    sed -i -e "s/\/URI (.*$NEEDLE.*/I,-5 d /g"  -e "s/.*$NEEDLE.*//g" $TMP_PDF
done
pdftk $TMP_PDF output $TARGET_PDF
rm -fr $TMP_PDF