#!/bin/bash
set -euo pipefail


cat << EOF | tee /usr/bin/zfs-system-snapshot-apt &> /dev/null
#!/bin/bash
set -euo pipefail


TIMESTAMP="\$(date +%Y_%m_%d-%H_%M_%S)"


if [[ -z "\$(zfs list -t snapshot | grep 'apt-\${TIMESTAMP}')" ]]; then
    zfs snapshot \$(zfs mount | grep 'ROOT' | sed 's| .*||')@apt-\${TIMESTAMP} && printf "\n- Snapshot taken\n\n"
fi
EOF

chmod \
	+x \
	/usr/bin/zfs-system-snapshot-apt

printf \
	'DPkg::Pre-Install-Pkgs {"/usr/bin/zfs-system-snapshot-apt";};\n' | \
	tee /etc/apt/apt.conf.d/90-zfs_system-snapshot &> /dev/null

printf \
	'DPkg::Post-Invoke {"apt moo";};\n' | \
	tee /etc/apt/apt.conf.d/99-apt_moo &> /dev/null