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

{
  options = {
    systemSettings = {
      dotfilesDir = lib.mkOption {
        default = "/etc/nixos";
        description = "Absolute path to the dotfiles directory";
        type = lib.types.path;
      };
      secretsFlakeDir = lib.mkOption {
        default = "/etc/nixos.secrets";
        description = "Absolute path to my secrets flake";
        type = lib.types.path;
      };
      systemBuilder.enable = lib.mkEnableOption "Enable automatic config updater and builder";
      systemBuilder.buildCronExpression = lib.mkOption {
        default = "Sat *-*-* 02:00:00"; # Sat morning at 2am
        description = "Cron expression for when the system should auto build config";
        type = lib.types.str;
      };
    };
  };
  config = {
    environment.systemPackages = with pkgs; [
      attic-client
      git
      nix-output-monitor
      (pkgs.writeScriptBin "phoenix" ''
        if [[ $EUID -ne 0 ]]; then
          echo "Error: This script must be run as root" 1>&2
          exit 1
        fi
        if [ "$1" = "sync" ]; then
          if [ "$#" -gt 1 ]; then
            echo "Warning: The 'sync' command has no subcommands (no $2 subcommand)";
          fi
          chown -R 0:0 ${config.systemSettings.dotfilesDir};
          chown -R 0:0 ${config.systemSettings.secretsFlakeDir};
          pushd ${config.systemSettings.dotfilesDir} &> /dev/null;
          nixos-rebuild switch;
          popd &> /dev/null;
          exit 0;
        elif [ "$1" = "update" ]; then
          pushd ${config.systemSettings.dotfilesDir} &> /dev/null;
          nix flake update "''${@:2}";
          popd &> /dev/null;
          #if [ "$#" -eq 1 ]; then
          #  pushd ${config.systemSettings.secretsFlakeDir} &> /dev/null;
          #  nix flake update;
          #  popd &> /dev/null;
          #fi
          exit 0;
        elif [ "$1" = "pull" ]; then
          if [ "$#" -gt 1 ]; then
            echo "Warning: The 'pull' command has no subcommands (no $2 subcommand)";
          fi
          chown -R $DOAS_USER:users ${config.systemSettings.dotfilesDir};
          chown -R $DOAS_USER:users ${config.systemSettings.secretsFlakeDir};
          pushd ${config.systemSettings.dotfilesDir} &> /dev/null;
          sudo -u $DOAS_USER git stash;
          sudo -u $DOAS_USER git pull;
          sudo -u $DOAS_USER git stash apply;
          popd &> /dev/null;
          pushd ${config.systemSettings.secretsFlakeDir} &> /dev/null;
          sudo -u $DOAS_USER git stash;
          sudo -u $DOAS_USER git pull;
          sudo -u $DOAS_USER git stash apply;
          popd &> /dev/null;
          chown -R 0:0 ${config.systemSettings.dotfilesDir};
          chown -R 0:0 ${config.systemSettings.secretsFlakeDir};
          exit 0;
        # TODO allow specifying host with $2 in build subcommand
        elif [ "$1" = "build" ]; then
          if [ "$#" -gt 1 ]; then
            echo "Warning: The 'build' command has no subcommands (no $2 subcommand)";
          fi
          chown -R 0:0 ${config.systemSettings.dotfilesDir};
          chown -R 0:0 ${config.systemSettings.secretsFlakeDir};
          pushd ${config.systemSettings.dotfilesDir} &> /dev/null;
          nixos-rebuild build --flake .#snowfire;
          attic push emmet ./result;
          rm ./result;
          nixos-rebuild build --flake .#duskfall;
          attic push emmet ./result;
          rm ./result;
          nixos-rebuild build --flake .#zenith;
          attic push emmet ./result;
          rm ./result;
          nixos-rebuild build --flake .#stardust;
          attic push emmet ./result;
          rm ./result;
          nixos-rebuild build --flake .#ori;
          attic push emmet ./result;
          rm ./result;
          exit 0;
        elif [ "$1" = "lock" ]; then
          if [ "$#" -gt 1 ]; then
            echo "Warning: The 'lock' command has no subcommands (no $2 subcommand)";
          fi
          chown -R 0:0 ${config.systemSettings.dotfilesDir};
          chown -R 0:0 ${config.systemSettings.secretsFlakeDir};
          exit 0;
        elif [ "$1" = "unlock" ]; then
          if [ "$#" -gt 1 ]; then
            echo "Warning: The 'unlock' command has no subcommands (no $2 subcommand)";
          fi
          chown -R $DOAS_USER:users ${config.systemSettings.dotfilesDir};
          chown -R $DOAS_USER:users ${config.systemSettings.secretsFlakeDir};
          exit 0;
        elif [ "$1" = "gc" ]; then
          if [ "$#" -gt 2 ]; then
            echo "Warning: The 'gc' command only accepts one argument (collect_older_than)";
          fi
          if [ "$2" = "full" ]; then
            nix-collect-garbage --delete-old;
          elif [ "$2" ]; then
            nix-collect-garbage --delete-older-than $2;
          else
            nix-collect-garbage --delete-older-than 30d;
          fi
          exit 0;
        fi
      '')
    ];
    systemd.services."phoenix-system-builder" = lib.mkIf config.systemSettings.systemBuilder.enable {
      path = with pkgs; [
        openssh git nix nixos-rebuild
      ];
      script = ''
        set -euo pipefail
	export NIX_PATH="nixpkgs=/nix/var/nix/profiles/per-user/root/channels/nixos:nixos-config=/etc/nixos/configuration.nix"
        echo "navigating to /etc/nixos";
        cd ${config.systemSettings.dotfilesDir};
        echo "running git pull";
        ${pkgs.git}/bin/git pull;
        echo "running nix flake update";
        nix flake update;
        ${pkgs.git}/bin/git stage *;
        ${pkgs.git}/bin/git commit -m "Updated system" || true;
        ${pkgs.git}/bin/git push || true;
        cd ${config.systemSettings.secretsFlakeDir};
        ${pkgs.git}/bin/git pull;
        chown -R 0:0 ${config.systemSettings.dotfilesDir};
        chown -R 0:0 ${config.systemSettings.secretsFlakeDir};
        cd ${config.systemSettings.dotfilesDir};
        ${config.system.build.nixos-rebuild}/bin/nixos-rebuild build --flake .#snowfire;
        ${pkgs.attic-client}/bin/attic push emmet ./result;
        rm ./result;
        ${config.system.build.nixos-rebuild}/bin/nixos-rebuild build --flake .#duskfall;
        ${pkgs.attic-client}/bin/attic push emmet ./result;
        rm ./result;
        ${config.system.build.nixos-rebuild}/bin/nixos-rebuild build --flake .#zenith;
        ${pkgs.attic-client}/bin/attic push emmet ./result;
        rm ./result;
        ${config.system.build.nixos-rebuild}/bin/nixos-rebuild build --flake .#stardust;
        ${pkgs.attic-client}/bin/attic push emmet ./result;
        rm ./result;
        ${config.system.build.nixos-rebuild}/bin/nixos-rebuild build --flake .#ori;
        ${pkgs.attic-client}/bin/attic push emmet ./result;
        rm ./result;
      '';
      serviceConfig = {
        Type = "simple";
        User = "root";
      };
    };
    systemd.timers."phoenix-system-builder-auto" = lib.mkIf config.systemSettings.systemBuilder.enable {
      wantedBy = [ "timers.target" ];
      timerConfig = {
        OnCalendar = config.systemSettings.systemBuilder.buildCronExpression;
        Unit = "phoenix-system-builder.service";
      };
    };
  };
}