#!/bin/bash
################################################################################
#
# Update the id lines of the files git is currently tracking in the index and
# which are new, modified, renamed, or copied.
#
# See set-id.pl for the format of the substitution.
#
# Uaage: cd git-repo; bin_path/update-id.sh
#
################################################################################

bin_dir=$(dirname "$0")

set -e
for path in $(git status --porcelain -z  | $bin_dir/changed-wt-files.pl); do
    echo 'updating $Id:$ in '$path
    new_name="$path-new"
    old_name="$path-old"

    # make sure the temporary names we are going to use don't already exist
    if [ -e "$new_name" ]; then
        echo "$0: $new_name exists -- did a previous update run fail?"
        exit 1
    fi
    if [ -e "$new_name" ]; then
        echo "$0: $new_name exists -- did a previous update run fail?"
        exit 1
    fi

    # update the id
    "$bin_dir/set-id.pl" "$path" < "$path" > "$new_name"
    if diff -q "$path" "$new_name" >/dev/null; then
        rm "$new_name"
    else
        cp -p "$path" "$old_name"
        mv "$new_name" "$path"
        rm "$old_name"
    fi
done