{ config, pkgs, lib, ... }:

let
  minecraft-server-args = [
    "-Xms2G"
    "-Xmx2G"
    "-Dsun.rmi.dgc.server.gcInterval=2157583646"
    "-XX:+UseG1GC"
    "-XX:+ParallelRefProcEnabled"
    "-XX:MaxGCPauseMillis=200"
    "-XX:+UnlockExperimentalVMOptions"
    "-XX:+DisableExplicitGC"
    "-XX:+AlwaysPreTouch"
    "-XX:G1NewSizePercent=30"
    "-XX:G1MaxNewSizePercent=40"
    "-XX:G1HeapRegionSize=8M"
    "-XX:G1ReservePercent=20"
    "-XX:G1HeapWastePercent=5"
    "-XX:G1MixedGCCountTarget=4"
    "-XX:InitiatingHeapOccupancyPercent=15"
    "-XX:G1MixedGCLiveThresholdPercent=90"
    "-XX:G1RSetUpdatingPauseTimePercent=5"
    "-XX:SurvivorRatio=32"
    "-XX:+PerfDisableSharedMem"
    "-XX:MaxTenuringThreshold=1"
  ];
  ops = pkgs.writeText "ops.json" (builtins.toJSON [{
    uuid = "140d177a-966f-41b8-a4c0-e305babd291b";
    name = "TLATER";
    level = 4;
    bypassesPlayerLimit = true;
  }]);
  whitelist = pkgs.writeText "whitelist.json" (builtins.toJSON [
    {
      uuid = "59cd1648-14a4-4bcf-8f5a-2e1bde678f2c";
      name = "romino25";
    }
    {
      uuid = "0ab6e3d1-544a-47e7-8538-2e6c248e49a4";
      name = "lasi25";
    }
    {
      uuid = "01c9e737-fc9d-4d55-b8c2-610ca80eb4be";
      name = "Nampeyo25";
    }
    {
      uuid = "140d177a-966f-41b8-a4c0-e305babd291b";
      name = "tlater";
    }
  ]);
  eula = pkgs.writeText "eula.txt" "eula=true";

in {
  nixpkgs.config.allowUnfreePredicate = pkg:
    builtins.elem (lib.getName pkg) [ "forge-server" ];

  users = {
    extraUsers.minecraft = {
      uid = config.ids.uids.minecraft;
      group = config.users.extraGroups.minecraft.name;
      isSystemUser = true;
      description = "Minecraft server user";
    };
    extraGroups.minecraft = { gid = config.ids.gids.minecraft; };
  };

  virtualisation.oci-containers.containers.minecraft-voor-kia = let
    properties = ./configs/minecraft/voor-kia/server.properties;
    icon = ./configs/minecraft/voor-kia/server-icon.png;
  in {
    image = "tlaternet/minecraft-voor-kia";

    imageFile = pkgs.dockerTools.buildImage {
      name = "tlaternet/minecraft-voor-kia";
      tag = "latest";
      contents = [
        (pkgs.local.forge-server.override {
          jre_headless = pkgs.jdk11_headless;
          mods = pkgs.local.voor-kia;
          modConfig = ./configs/minecraft/voor-kia/config;
          defaultconfigs = ./configs/minecraft/voor-kia/defaultconfigs;
        })
      ];

      config = let
        uid = toString config.users.extraUsers.minecraft.uid;
        gid = toString config.users.extraGroups.minecraft.gid;
      in {
        Cmd = [ "forge-server" ] ++ minecraft-server-args;
        WorkingDir = "/var/lib/minecraft";
        Volumes = {
          "/var/lib/minecraft" = { };
          # Required because some things will try to write to /tmp,
          # which doesn't exist if it's not defined as a volume.
          "/tmp" = { };
        };
        ExposedPorts = { "25565" = { }; };
        User = "${uid}:${gid}";
      };
    };

    extraOptions = [ "--cpus=1.0" ];
    autoStart = false;
    ports = [ "25565:25565" ];
    volumes = [
      "minecraft:/var/lib/minecraft"
      "${eula}:/var/lib/minecraft/eula.txt:ro"
      "${icon}:/var/lib/minecraft/server-icon.png:ro"
      "${ops}:/var/lib/minecraft/ops.json:ro"
      "${properties}:/var/lib/minecraft/server.properties:ro"
      "${whitelist}:/var/lib/minecraft/whitelist.json:ro"
    ];
  };

  systemd.timers.podman-minecraft-voor-kia-off = {
    description = "Turns off the minecraft server every day at 4 am";
    wantedBy = [ "podman-minecraft-voor-kia.service" ];
    timerConfig = {
      Unit = "podman-minecraft-voor-kia-starter@stop.service";
      OnCalendar = "04:00:00";
    };
  };

  systemd.timers.podman-minecraft-voor-kia-on = {
    description = "Turns on the minecraft server every day at 2 pm";
    wantedBy = [ "podman-minecraft-voor-kia.service" ];
    timerConfig = {
      Unit = "podman-minecraft-voor-kia-starter@start.service";
      OnCalendar = "14:00:00";
    };
  };

  systemd.services."podman-minecraft-voor-kia-starter@" = {
    description = "Unit to stop/start the minecraft server";
    serviceConfig = {
      ExecStart =
        "${pkgs.systemd}/bin/systemctl %i podman-minecraft-voor-kia.service";
      Type = "oneshot";
    };
  };
}