nixos-config/profiles/servers/minecraft.nix

{ config, pkgs, lib, inputs, ... }:
let
  jre17 = pkgs.temurin-bin-17;
  jvmOpts = lib.concatStringsSep " " [
    "-XX:+UseG1GC"
    "-XX:+ParallelRefProcEnabled"
    "-XX:MaxGCPauseMillis=200"
    "-XX:+UnlockExperimentalVMOptions"
    "-XX:+DisableExplicitGC"
    "-XX:+AlwaysPreTouch"
    "-XX:G1NewSizePercent=40"
    "-XX:G1MaxNewSizePercent=50"
    "-XX:G1HeapRegionSize=16M"
    "-XX:G1ReservePercent=15"
    "-XX:G1HeapWastePercent=5"
    "-XX:G1MixedGCCountTarget=4"
    "-XX:InitiatingHeapOccupancyPercent=20"
    "-XX:G1MixedGCLiveThresholdPercent=90"
    "-XX:G1RSetUpdatingPauseTimePercent=5"
    "-XX:SurvivorRatio=32"
    "-XX:+PerfDisableSharedMem"
    "-XX:MaxTenuringThreshold=1"
  ];

  rsyncSSHKeys = config.users.users.${config.mainuser}.openssh.authorizedKeys.keys;

  defaults = {
    allow-flight = true;
    difficulty = 2;
    # 5 minutes tick timeout, for heavy packs
    max-tick-time = 5 * 60 * 1000;
    online-mode = false;
    spawn-protection = 0;
  };
in {
  imports = [ inputs.mms.module ];
  services.modded-minecraft-servers = {
    eula = true;
    instances = {
      statech = {
        enable = false;
        inherit rsyncSSHKeys jvmOpts;
        jvmMaxAllocation = "6144m";
        jvmInitialAllocation = "6144m";
        jvmPackage = jre17;
        serverConfig = defaults // {
          server-port = 25565;
          rcon-port = 25566;
          motd = "StaTech";
          max-world-size = 50000;
          level-seed = "-4411466874705470064";
        };
      };
    };
  };
  persist.state.directories = [ "/var/lib/mc-statech" ];

  # secrets.restic-mc-pass.services = [ "restic-backups-mc-servers.service" ];
  # secrets.restic-mc-repo.services = [ "restic-backups-mc-servers.service" ];
  # services.restic.backups.mc-servers = {
  #   initialize = true;
  #   passwordFile = config.secrets.restic-mc-pass.decrypted;
  #   repositoryFile = config.secrets.restic-mc-repo.decrypted;
  #   paths = [ "/var/lib/mc-statech" ];
  #   exclude = [ "/var/lib/mc-statech/backups" ];
  #   environmentFile = "${pkgs.writeText "restic.env" ''
  #     GOMAXPROCS=1
  #     MCRCON_PORT=25566
  #     MCRCON_PASS=whatisloveohbabydonthurtmedonthurtmenomore
  #   ''}";
  #   extraBackupArgs = [ "--no-scan" ];
  #   backupPrepareCommand = ''
  #     if ! systemctl is-active --quiet mc-statech.service; then
  #       echo "Minecraft server is not active. Skipping restic backup."
  #       exit 1
  #     fi
  #     ${pkgs.mcrcon}/bin/mcrcon "say Restic backup is started!" save-off "save-all"
  #     sleep 3
  #   '';
  #   backupCleanupCommand = ''
  #     systemctl is-active --quiet mc-statech.service && ${pkgs.mcrcon}/bin/mcrcon "say Restic backup is done!" save-on
  #   '';
  #   timerConfig = {
  #     OnCalendar = "*:0/15";
  #   };
  #   pruneOpts = [
  #     "--keep-last 12"
  #     "--keep-hourly 12"
  #     "--keep-daily 5"
  #     "--keep-weekly 2"
  #     "--keep-monthly 0"
  #     "--keep-yearly 0"
  #   ];
  # };
}