#!/bin/bash

VERBOSE=0

if [ "$1" = "-v" ] ; then
    VERBOSE=1
    shift
fi

cd $1

if [ "$2"x != ""x ] ; then
    EXT="$2"
fi

if [ "$CHECKSUMS"x = ""x ] ; then
    CHECKSUMS="sha1 md5 sha512 sha256"
fi

for SUM in $CHECKSUMS; do
	UPSUM=$(echo $SUM | tr 'a-z' 'A-Z')
	FILE=$UPSUM"SUMS"$EXT
	if [ $VERBOSE -eq 1 ] ; then
	    echo "Clearing $PWD/$FILE"
	fi
	:> $FILE
done

# Ordering is important in the "find" call here - we *really* want to
# get the jigdo files before the iso files, so we can use the
# checksums there first instead of re-calculating them
for file in $(find * \
                   -name '*.jigdo' -o -name '*.template' \
                   -o -name '*.iso' -o -name '*.torrent'); do
    iso=""
    case $file in
        *.jigdo)
            iso=${file%%.jigdo}.iso
            JIGDO=1
            ;;
        *.iso)
            iso=$file
            JIGDO=0
            ;;
        *.template|*.torrent)
            ;;
        *)
            echo "Found unexpected file $file!"
            exit 1
            ;;
    esac

	for SUM in $CHECKSUMS; do
		UPSUM=$(echo $SUM | tr 'a-z' 'A-Z')
		FILE=$UPSUM"SUMS"$EXT
		CMD="$SUM"sum

		if [ "$iso"x != ""x ]; then
		    grep -q $iso $FILE
		    if [ $? -ne 0 ] ; then
			CKSUM=""
			if [ "$JIGDO" == 1 ] ; then
			    CKSUM=$(zcat -f $file | \
					grep -i "Image Hex $CMD" | \
			                awk '{print $5}')
			fi
			if [ "$CKSUM"x != ""x ] ; then
			    echo "$CKSUM  $iso" >> $FILE
			    grep $iso $FILE
			else
			    echo "No Jigdo help for $SUM, doing it the long way with $CMD"
			    $CMD $iso >> $FILE
			    grep $iso $FILE
			fi
		    fi
		fi

        # Also add the template, jigdo and torrent files to the SUMS,
        # if they exist
        case $file in
            *.template|*.jigdo|*.torrent)
                $CMD $file >> $FILE
                grep $file $FILE
                ;;
        esac
    done
done