setup.sh

#!/usr/bin/env bash
set -euo pipefail

REPO_DIR="$(cd "$(dirname "$0")" && pwd)"

# --- Get hostname ---
if [ -n "${1:-}" ]; then
  HOSTNAME="$1"
else
  read -rp "Hostname for this machine: " HOSTNAME
fi

if [ -z "$HOSTNAME" ]; then
  echo "Error: hostname cannot be empty"
  exit 1
fi

HOST_DIR="$REPO_DIR/hosts/$HOSTNAME"

if [ -d "$HOST_DIR" ]; then
  echo "Error: hosts/$HOSTNAME already exists"
  exit 1
fi

# --- Detect architecture ---
ARCH="$(uname -m)"
case "$ARCH" in
  x86_64)  SYSTEM="x86_64-linux" ;;
  aarch64) SYSTEM="aarch64-linux" ;;
  *)
    echo "Error: unsupported architecture: $ARCH"
    exit 1
    ;;
esac

echo "Detected architecture: $SYSTEM"

# --- Detect bootloader type ---
if [ -d /sys/firmware/efi ]; then
  BOOT_MODE="efi"
  echo "Detected boot mode: EFI (systemd-boot)"
else
  BOOT_MODE="bios"
  echo "Detected boot mode: Legacy BIOS (GRUB)"
fi

# --- Pick home-manager config ---
echo ""
echo "Which home-manager config?"
echo "  1) home.nix              (full — desktop with i3, kitty, pywal, etc.)"
echo "  2) hosts/aarch64/home.nix (arm — aarch64/UTM VM setup)"
read -rp "Choice [1/2]: " HOME_CHOICE

case "${HOME_CHOICE:-1}" in
  1) HOME_MODULE="./home.nix" ;;
  2) HOME_MODULE="./hosts/aarch64/home.nix" ;;
  *)
    echo "Error: invalid choice"
    exit 1
    ;;
esac

# --- Generate hardware configuration ---
echo ""
echo "Generating hardware configuration (requires sudo)..."
mkdir -p "$HOST_DIR"
sudo nixos-generate-config --show-hardware-config > "$HOST_DIR/hardware-configuration.nix"
echo "Wrote hosts/$HOSTNAME/hardware-configuration.nix"

# --- Create configuration.nix ---
cat > "$HOST_DIR/configuration.nix" << 'NIXEOF'
{ config, lib, pkgs, ... }:

{
  imports = [
    ./hardware-configuration.nix
  ];

  # Bootloader
  BOOTLOADER_PLACEHOLDER

  # Networking
  networking.hostName = "HOSTNAME_PLACEHOLDER";
  networking.networkmanager.enable = true;

  # Time and locale
  time.timeZone = "Europe/London";

  # Security
  security.rtkit.enable = true;

  # Audio (PipeWire)
  services.pipewire = {
    enable = true;
    alsa.enable = true;
    pulse.enable = true;
    wireplumber.enable = true;
  };

  # Display and desktop
  services.xserver.enable = true;
  services.xserver.xkb.layout = "gb";
  services.displayManager.defaultSession = "none+i3";
  services.displayManager.sddm = {
    enable = true;
    theme = "sddm-astronaut-theme";
    extraPackages = [
      (pkgs.sddm-astronaut.override { embeddedTheme = "astronaut"; })
    ];
  };

  services.xserver.windowManager.i3 = {
    enable = true;
    package = pkgs.i3;
    extraPackages = with pkgs; [
      rofi
      i3lock
      kitty
      dex
      xss-lock
      networkmanagerapplet
    ];
  };

  # Services
  services.tailscale.enable = false;

  # Users
  users.users.sage = {
    isNormalUser = true;
    shell = pkgs.zsh;
    extraGroups = [ "wheel" "networkmanager" "audio" ];
    initialPassword = "changeme";
  };

  # System-wide programs
  programs.zsh.enable = true;

  programs.firefox = {
    enable = true;
    policies = {
      ExtensionSettings = {
        "tridactyl.vim@cmcaine.co.uk" = {
          install_url = "https://addons.mozilla.org/firefox/downloads/latest/tridactyl-vim/latest.xpi";
          installation_mode = "force_installed";
        };
      };
    };
  };

  # System packages
  environment.systemPackages = with pkgs; [
    vim
    wget
    git
    pamixer
    playerctl
    pavucontrol
    brightnessctl
    (sddm-astronaut.override { embeddedTheme = "astronaut"; })
  ];

  # Environment variables
  environment.sessionVariables = {
    TERMINAL = "kitty";
  };

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

  # Enable flakes
  nix.settings.experimental-features = [ "nix-command" "flakes" ];

  system.stateVersion = "25.05";
}
NIXEOF

sed -i "s/HOSTNAME_PLACEHOLDER/$HOSTNAME/" "$HOST_DIR/configuration.nix"

if [ "$BOOT_MODE" = "efi" ]; then
  BOOT_CONFIG="boot.loader.systemd-boot.enable = true;\n  boot.loader.efi.canTouchEfiVariables = true;"
else
  BOOT_CONFIG="boot.loader.grub.enable = true;\n  boot.loader.grub.device = \"/dev/sda\"; # adjust to your disk"
fi
sed -i "s|BOOTLOADER_PLACEHOLDER|$BOOT_CONFIG|" "$HOST_DIR/configuration.nix"

echo "Wrote hosts/$HOSTNAME/configuration.nix"

# --- Add entry to flake.nix ---
# Insert new host block before the final two closing braces
LAST_CONFIG_LINE=$(grep -n '    };' "$REPO_DIR/flake.nix" | tail -1 | cut -d: -f1)
FLAKE="$REPO_DIR/flake.nix"
TMPFLAKE="$FLAKE.tmp"

{
  head -n "$LAST_CONFIG_LINE" "$FLAKE"
  cat <<EOF

    # $HOSTNAME
    nixosConfigurations.$HOSTNAME = nixpkgs.lib.nixosSystem {
      system = "$SYSTEM";
      modules = [
        ./hosts/$HOSTNAME/configuration.nix
        home-manager.nixosModules.home-manager
        {
          home-manager.useGlobalPkgs = true;
          home-manager.useUserPackages = true;
          home-manager.users.sage = import $HOME_MODULE;
        }
      ];
    };
EOF
  tail -n +"$((LAST_CONFIG_LINE + 1))" "$FLAKE"
} > "$TMPFLAKE"

mv "$TMPFLAKE" "$FLAKE"
echo "Added $HOSTNAME to flake.nix"

# --- Summary ---
echo ""
echo "Setup complete! To build:"
echo "  sudo nixos-rebuild switch --flake ~/nixos-config#$HOSTNAME"
echo ""
echo "Review and customize hosts/$HOSTNAME/configuration.nix as needed."