#!/bin/sh
# Creates a keyring from a set of changesets. Can run in incremental or
# full build mode.
set -e

incremental=
if [ "$1" = "-i" ]; then
	shift 1
	incremental=1
elif [ "$1" = "-I" ]; then
	shift 1
	incremental=1
	force=1
fi

if [ -z "$1" ] || [ -z "$2" ]; then
	echo "Usage: jetring-build [-i] keyring changesetdir" >&2
	exit 1
fi

# avoid gnupg touching ~/.gnupg
GNUPGHOME=$(mktemp -d -t jetring.XXXXXXXX)
export GNUPGHOME
trap cleanup exit
cleanup () {
	rm -rf "$GNUPGHOME"
}

keyring=$(readlink -f "$1") # gpg works better with absolute keyring paths
changesetdir="$2"

if [ ! -e "$changesetdir/index" ]; then
	echo "$changesetdir/index not found" >&2
	exit 1
fi

if [ -s "$changesetdir/index" ]; then
	jetring-checksum "$changesetdir"
fi

if [ -n "$JETRING_SIGN" ]; then
	JETRING_SIGN=$(readlink -f "$JETRING_SIGN")
	gpg --no-auto-check-trustdb --options /dev/null \
		--no-default-keyring --keyring "$JETRING_SIGN" \
		--verify "$changesetdir/index.gpg" "$changesetdir/index"
fi

if [ "$incremental" ]; then
	if [ ! -e "$keyring.lastchangeset" ]; then
		if [ ! "$force" ]; then
			echo "$keyring.lastchangeset not found, cannot do incremental update" >&2
			exit 1
		else
			incremental=
		fi
	else
		if [ ! -e "$keyring" ]; then
			if [ ! "$force" ]; then
				echo "$keyring not found, cannot do incremental update" >&2
			else
				incremental=
			fi
		else
			skiptil=$(cat $keyring.lastchangeset)
			echo "Skipping forward past changeset $skiptil ..."
		fi
	fi
else
	if [ -e "$keyring" ]; then
		echo "$keyring already exists, and not in incremental mode, not modifying" >&2
		exit 1
	fi
fi
touch "$keyring"

for changeset in $(cut -d " " -f 3 "$changesetdir/index"); do
	if [ -n "$skiptil" ]; then
		if [ "$changeset" = "$skiptil" ]; then
			skiptil=
		fi
		continue
	fi
	echo "Applying $changesetdir/$changeset ..."
	if ! jetring-apply "$keyring" "$changesetdir/$changeset"; then
		echo "Failed! Leaving keyring in $keyring.error" >&2
		mv -f "$keyring" "$keyring.error"
		exit 1
	fi
done

if [ -n "$skiptil" ]; then
	echo "Did not find last applied changeset, $skiptil, incremental update failed" >&2
	exit 1
fi

echo "$changeset" > "$keyring.lastchangeset"
echo "All changesets applied ok."