#! /bin/bash

# replace {release} in a sources.list template with the value of $release
# replace {apt_cdn} with the value of $apt_cdn

# $1 is the class name used
# $2 is the path to the file copied

# check if a variable of the form {varname} was used at all
grep -q '{' $2 || exit 0

if [ -z "$release" ]; then
    echo "\$release is undefined. No substitution performed in $2."
else
    sed -i -e "s/{release}/$release/g" $2
fi

if [ -z "$apt_cdn" ]; then
    echo "\$apt_cdn not defined. not substituting in $2."
else
    sed -i -e "s#{apt_cdn}#$apt_cdn#g" $2
fi