used_bibliography_biber

#!/bin/bash

# Usage:
# used_bibliography file_without_extension
# or
# used_bibliography file_without_extension.bcf

# Parse the arguments
if [ ! $# = 1 ]; then
	echo "Usage: $(basename $0) file.bcf"
	exit
fi

# Search the bcf-file
file=$1

if ! [ -e $file ] & [ -e $file.bcf ]; then
	file=$file.bcf
fi

if ! [ -e $file ]; then
	echo "Can't find $file."
	exit 1
fi

# Search for "<bcf:citekey>.*</bcf:citekey>" in the bcf-file => these are the cited references
cites=$(grep -Po '<bcf:citekey( order="\d*")>\K[^<]*' $file | sort -u )

# Search for "<bcf:datasource type="file" datatype="bibtex">.*</bcf:datasource>" in the bcf-file => these are the used bib-files.
    
bibs=$(grep -Po '<bcf:datasource type="file" datatype="bibtex">\K[^<]*' $file | sort -u | xargs kpsewhich)

# Extract the citations from the bib-files.
for cite in $cites; do
	# echo "% Search for $cite"
	for bib in $bibs; do
		# echo "% Search in file $bib"
		awk "BEGIN {RS=\"\n@\"} /{$cite,/{sub(\"^@?\",\"@\");print \"% Search for $cite, Found in file $bib:\n\" \$0 ;}" $bib
	done
done