#!/bin/sh
#
# An example hook script to store metadata information using
# metastore on each commit.
#
# WARNING:
#
# If the commit is aborted (e.g. by not entering any synopsis),
# then updated metastore file (.metadata by default) is not reverted,
# so its new version remains in the index.
# To undo any changes in metastore file written since HEAD commit,
# you may want to reset and checkout HEAD version of the file:
#
#     git reset HEAD -- .metadata
#     git checkout HEAD -- .metadata

MSFILE=".metadata"

exit_on_fail() {
	"$@"
	if [ $? -ne 0 ]; then
		echo "Failed to execute: $@" >&2
		exit 1
	fi
}

if git rev-parse MERGE_HEAD >/dev/null 2>&1 \
		&& [ -e "$MSFILE" ] \
		&& ! metastore -c -q -f "$MSFILE"; then
	echo "In git Conflict resolution, and saved metadata does not match filesystem"
	echo "metadata. Unable to fix automatically. Try:"
	echo "  metastore -cf \"$MSFILE\"    -- Shows where the differences are"
	echo "  metastore -df \"$MSFILE\"    -- Shows the stored metadata"
	echo "  metastore -sf \"$MSFILE\"    -- Save current filesystem metadata as-is"
	echo "  metastore -af \"$MSFILE\"    -- Apply saved metadata to filesystem"
	exit 1
fi

exit_on_fail \
	metastore -s -f "$MSFILE"

# If it's first metastore commit, store again to include $MSFILE in $MSFILE.
if ! git-ls-tree --name-only HEAD 2>/dev/null | grep -Fqx "$MSFILE"; then
	exit_on_fail \
		metastore -s -f "$MSFILE"
fi

if [ ! -e "$MSFILE" ]; then
	echo "\"$MSFILE\" missing" >&2
	exit 1
fi

exit_on_fail \
	git-add "$MSFILE"

exit 0