#!/bin/bash
# makerdf.sh - Update an RDF File In-Place
# Author: Sean B. Palmer, inamidst.com

# Make a backup of the input
[[ -d ~/.makerdf ]] || mkdir ~/.makerdf
MD5=$(md5sum $1 | cut -d' ' -f 1)
cp -p $1 ~/.makerdf/$MD5.rdf

if [[ ! -f ~/.makerdf/$MD5.rdf ]]
then echo "Error! Couldn't create backup"
     exit 1
fi

# Put the Notation3 in a temporary file
N3TMP=$$.makerdf.n3.tmp
sed -n '/<!-- Notation3 Source:/,/-->/ p' $1 | \
   sed '1 s/^/# /; $ s/^/# /' > $N3TMP

# Check that we got some output
grep . $N3TMP &> /dev/null
if (( $? ))
then echo 'Error! Got zero triples'
     rm -f $N3TMP
     exit 1
fi

# Update the file in-place
cwm --n3 $N3TMP --rdf | \
   egrep -v '<!-- *using base' > $1
STATUS=$?

# Check that the above worked
if (( ! $STATUS ))
then sed '1 s/^# /\n/; $ s/^# //' $N3TMP >> $1
     echo "Updated: $1"
else echo "Error! Restoring backup from ~/.makerdf/$MD5.rdf"
     cp -p ~/.makerdf/$MD5.rdf $1 || \
        echo "Error! Can't restore the backup!" # d'oh
fi

# Delete the temporary file and exit
rm -f $N3TMP
exit $STATUS

# [EOF]