# It sets up system-level configuration and integrates with home-manager.
{
  config,
  pkgs,
  lib,
  username,
  ...
}: {
  # Nix configuration
  nix = {
    settings = {
      # Enable flakes and new nix command
      experimental-features = ["nix-command" "flakes"];
      # Avoid unwanted garbage collection when using nix-direnv
      keep-outputs = true;
      keep-derivations = true;
    };
  };

  # Allow unfree packages
  nixpkgs.config.allowUnfree = true;

  system = {
    primaryUser = username;
    keyboard = {
      enableKeyMapping = true;
      remapCapsLockToControl = true;
    };
    startup.chime = false;

    defaults = {
      spaces.spans-displays = false;
      loginwindow = {
        GuestEnabled = false;
        DisableConsoleAccess = true;
      };


      dock = {
        autohide = true;
        autohide-delay = 0.0;
        autohide-time-modifier = 0.0;
        orientation = "bottom";
        dashboard-in-overlay = true;
        largesize = 85;
        tilesize = 50;
        magnification = true;
        launchanim = false;
        mru-spaces = false;
        show-recents = false;
        show-process-indicators = false;
        static-only = true;
      };

      finder = {
        AppleShowAllExtensions = true;
        AppleShowAllFiles = true;
        CreateDesktop = false;
        FXDefaultSearchScope = "SCcf"; # current folder
        QuitMenuItem = true;
      };

      NSGlobalDomain = {
        NSAutomaticSpellingCorrectionEnabled = false;
        NSAutomaticCapitalizationEnabled = false;
        NSAutomaticPeriodSubstitutionEnabled = false;
        NSAutomaticDashSubstitutionEnabled = false;
        NSAutomaticQuoteSubstitutionEnabled = false;
        NSAutomaticWindowAnimationsEnabled = false;
        NSDocumentSaveNewDocumentsToCloud = false;
        ApplePressAndHoldEnabled = false;

        KeyRepeat = 2;
        InitialKeyRepeat = 10;
        # Enable subpixel font rendering on non-Apple LCDs
        # Reference: https://github.com/kevinSuttle/macOS-Defaults/issues/17#issuecomment-266633501
        AppleFontSmoothing = 2;
        # Finder: show all filename extensions
        AppleShowAllExtensions = true;
      };
      CustomUserPreferences = {
        LaunchServices = {
          # Whether to enable quarantine for downloaded applications
          LSQuarantine = false;
        };
        trackpad = {
          Clicking = true;
          TrackpadRightClick = true;
        };
        "com.apple.systempreferences" = {
          # Disable Resume system-wide
          NSQuitAlwaysKeepsWindows = false;
        };
        "com.apple.desktopservices" = {
          # Avoid creating .DS_Store files on network or USB volumes
          DSDontWriteNetworkStores = true;
          DSDontWriteUSBStores = true;
        };
        "com.apple.screensaver" = {
          # Require password immediately after sleep or screen saver begins
          askForPassword = 1;
          askForPasswordDelay = 0;
        };
        "com.apple.AdLib" = {
          # Don't fucking track me...
          allowApplePersonalizedAdvertising = false;
        };
        "com.apple.BluetoothAudioAgent" = {
          # Increase sound quality for Bluetooth headphones/headsets
          "Apple Bitpool Min (editable)" = -40;
        };
        "com.apple.dashboard" = {
          # Disable Dashboard
          mcx-disabled = true;
        };
        alf = {
          # Enables Firewall
          globalstate = 1;
          # Enable logging of requests
          loggingenabled = 1;
          # Drops incoming requests via ICMP such as ping requests
          stealthenabled = 1;
        };
      };
    };
  };

  users.users.${username} = {
    name = username;
    home = "/Users/${username}";
    openssh.authorizedKeys.keys = [
      "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIFaIAP/ZJ7+7jeR44e1yIJjfQAB6MN351LDKJAXVF62P"
      "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAILAzuPy7D/54GxMq9Zhz0CUjaDnEQ6RkQ/yqVYl7U55k"
    ];
  };

  # Used for backwards compatibility, read the changelog before changing.
  # $ darwin-rebuild changelog
  system.stateVersion = 5;
}