nixos/home/services/backup-home.nix

{ pkgs, ... }:
let
  # Backup home script
  backup-home = pkgs.writeShellScriptBin "backup-home.sh"
    ''
      export RESTIC_PASSWORD="gunter.home.2rjus.net"
      export RESTIC_REPOSITORY="rest:http://10.69.12.52:8000/gunter.home.2rjus.net"

      # Send start notification
      ${pkgs.libnotify}/bin/notify-send -e -t 3000 "Backup started" "Backup of /home/torjus started"
      retval=$?
      if [ $retval -ne 0 ]; then
          echo "Failed to send notification"
          exit 1
      fi

      # Do the backup
      SECONDS=0
      ${pkgs.restic}/bin/restic backup /home/torjus \
          --exclude '/home/torjus/.cache' \
          --exclude '/home/torjus/.local/share/Steam' \
          --exclude '/home/torjus/git/nixpkgs'
      retval=$?
      if [ $retval -ne 0 ]; then
          notify-send -u critical "Backup failed" "Backup of /home/torjus failed"
          exit 1
      fi

      # Remove old snapshots and prune
      ${pkgs.restic}/bin/restic forget -d 7 -w 4 -m 6 --keep-within 1d --prune

      # Gather statistics
      stats=$(${pkgs.restic}/bin/restic stats --json)
      stats_raw=$(${pkgs.restic}/bin/restic stats --mode=raw-data --json)

      raw_size=$(${pkgs.jq}/bin/jq -r '.total_size' <<< $stats_raw \
          | ${pkgs.coreutils}/bin/numfmt --to=iec --suffix=B --format="%.2f")
      total_size=$(${pkgs.jq}/bin/jq -r '.total_size' <<< $stats \
          | ${pkgs.coreutils}/bin/numfmt --to=iec --suffix=B --format="%.2f")
      total_files=$(${pkgs.jq}/bin/jq -r '.total_file_count' <<< $stats \
          | ${pkgs.coreutils}/bin/numfmt --to=iec)
      total_snapshots=$(${pkgs.jq}/bin/jq -r '.snapshots_count' <<< $stats)
      message="$total_files files\n$total_snapshots snapshots\n$raw_size ($total_size)"

      # Send completion notification
      ${pkgs.libnotify}/bin/notify-send -i checkmark -e -t 10000 \
          "Backup of /home/torjus completed in ''${SECONDS}s" "$message"
      retval=$?
      if [ $retval -ne 0 ]; then
          echo "Failed to send notification"
          exit 1
      fi
    '';
in
{
  systemd.user.services.backup-home = {
    Unit = {
      Description = "Backup home directory";
      After = [ "network.target" ];
    };
    Service = {
      Type = "oneshot";
      ExecStart = "${backup-home}/bin/backup-home.sh";
    };
  };
  systemd.user.timers.backup-home = {
    Unit = {
      Description = "Backup home directory";
      After = [ "network.target" ];
    };
    Timer = {
      OnCalendar = "*-*-* *:00:00";
      Persistent = true;
    };
    Install = {
      WantedBy = [ "timers.target" ];
    };
  };
}