if [[ -f '/etc/apt/sources.list.d/voco-focal-stable-main.list' ]]; then exit 0; fi
if [[ -n "$(ls /etc/apt/sources.list.d/voco-*.list &>/dev/null)" ]]; then echo "A conflicting Voco repo has already been added. Aborting." >&2; exit 1; fi
wget -qO- 'http://sources.vocowire.com/public.key' | sudo apt-key add - \
&& echo 'deb [arch=amd64] http://sources.vocowire.com focal/stable main' | sudo tee '/etc/apt/sources.list.d/voco-focal-stable-main.list' \
&& apt-get -o DPkg::Lock::Timeout=3600 update