home/hosts/odin/system/mergerfs.nix

{
  config,
  pkgs,
  ...
}:
{
  environment.systemPackages = with pkgs; [
    mergerfs
    mergerfs-tools
  ];

  users.groups.storage.gid = 992;

  fileSystems."/mnt/storage" = {
    device = "/mnt/data*";
    options = [
      "category.create=mfs"
      "defaults"
      "allow_other"
      "use_ino"
      "moveonenospc=true"
      "minfreespace=25G"
      "func.getattr=newest"
      "func.create=ff"
      "fsname=storage"
      "gid=${toString config.users.groups.storage.gid}"
    ];
    fsType = "fuse.mergerfs";
  };

  systemd.services."chown-storage" = {
    description = "Ensure correct group ownership on the storage pool";

    wantedBy = [ "local-fs.target" ];
    after = [ "local-fs.target" ];

    script = ''
      ${pkgs.coreutils}/bin/chown -R :storage /mnt/data*
      ${pkgs.coreutils}/bin/chmod -R 0775 /mnt/data*
      ${pkgs.coreutils}/bin/chown -R :storage /mnt/parity*
      ${pkgs.coreutils}/bin/chmod -R 0775 /mnt/parity*
    '';

    serviceConfig = {
      Type = "oneshot";
      RemainAfterExit = "yes";
    };
  };
}