{
  pkgs,
  host,
  backupFiles ? [".config/mimeapps.list.backup"],
  ...
}: let
  backupFilesString = pkgs.lib.strings.concatStringsSep " " backupFiles;
in
  pkgs.writeShellScriptBin "ncli" ''
    #!${pkgs.bash}/bin/bash
    set -euo pipefail

    # --- Configuration ---
    PROJECT="NixOS"
    HOST="${host}"
    BACKUP_FILES_STR="${backupFilesString}"
    VERSION="2.0.0"
    FLAKE_NIX_PATH="$HOME/$PROJECT/flake.nix"

    read -r -a BACKUP_FILES <<< "$BACKUP_FILES_STR"

    # --- Helper Functions ---
    print_help() {
      echo "NixOS CLI Utility -- version $VERSION"
      echo ""
      echo "Usage: ncli [command]"
      echo ""
      echo "System Commands:"
      echo "  rebuild         - Rebuild the NixOS system configuration for current host ($HOST)."
      echo "  rebuild-boot    - Rebuild and set as boot default (activates on next restart)."
      echo "  update          - Update the flake and rebuild the system for current host."
      echo "  switch-host     - Interactive host switcher (same as ./switch-host.sh)."
      echo ""
      echo "Multi-Host Commands:"
      echo "  build [HOST]    - Build configuration for specific host (no activation)."
      echo "  deploy [HOST]   - Build and switch to specific host configuration."
      echo "  list-hosts      - List all available host configurations."
      echo ""
      echo "Maintenance Commands:"
      echo "  cleanup         - Clean up old system generations. Can specify a number to keep."
      echo "  diag            - Create a system diagnostic report (saves to ~/diag.txt)."
      echo "  list-gens       - List user and system generations."
      echo "  trim            - Trim filesystems to improve SSD performance."
      echo ""
      echo "Git Commands:"
      echo "  commit [msg]    - Add all changes and commit with message."
      echo "  push            - Push changes to origin."
      echo "  pull            - Pull latest changes from origin."
      echo "  status          - Show git status."
      echo ""
      echo "  help            - Show this help message."
      echo ""
      echo "Current Host: $HOST"
    }

    handle_backups() {
      if [ ''${#BACKUP_FILES[@]} -eq 0 ]; then
        echo "No backup files configured to check."
        return
      fi

      echo "Checking for backup files to remove..."
      for file_path in "''${BACKUP_FILES[@]}"; do
        full_path="$HOME/$file_path"
        if [ -f "$full_path" ]; then
          echo "Removing stale backup file: $full_path"
          rm "$full_path"
        fi
      done
    }

    list_available_hosts() {
      if [ ! -d "$HOME/$PROJECT/hosts" ]; then
        echo "Error: Hosts directory not found at $HOME/$PROJECT/hosts" >&2
        return 1
      fi

      echo "Available hosts:"
      for host_dir in "$HOME/$PROJECT/hosts"/*; do
        if [ -d "$host_dir" ]; then
          hostname=$(basename "$host_dir")
          if [ "$hostname" != "default" ]; then
            if [ "$hostname" = "$HOST" ]; then
              echo "  • $hostname (current)"
            else
              echo "  • $hostname"
            fi
          fi
        fi
      done
    }

    validate_host() {
      local target_host="$1"
      if [ ! -d "$HOME/$PROJECT/hosts/$target_host" ]; then
        echo "Error: Host '$target_host' not found in $HOME/$PROJECT/hosts/" >&2
        echo "Available hosts:" >&2
        list_available_hosts >&2
        return 1
      fi
      return 0
    }

    build_host() {
      local target_host="$1"
      validate_host "$target_host" || return 1

      echo "Building configuration for host: $target_host"
      cd "$HOME/$PROJECT" || { echo "Error: Could not change to $HOME/$PROJECT"; return 1; }

      if nixos-rebuild build --flake ".#$target_host"; then
        echo "✓ Build successful for $target_host"
        return 0
      else
        echo "✗ Build failed for $target_host" >&2
        return 1
      fi
    }

    deploy_host() {
      local target_host="$1"
      validate_host "$target_host" || return 1

      echo "Deploying configuration for host: $target_host"
      cd "$HOME/$PROJECT" || { echo "Error: Could not change to $HOME/$PROJECT"; return 1; }

      if sudo nixos-rebuild switch --flake ".#$target_host"; then
        echo "✓ Successfully deployed $target_host configuration"
        echo "System is now running $target_host configuration."
        return 0
      else
        echo "✗ Deployment failed for $target_host" >&2
        return 1
      fi
    }

    # --- Main Logic ---
    if [ "$#" -eq 0 ]; then
      echo "Error: No command provided." >&2
      print_help
      exit 1
    fi

    case "$1" in
      cleanup)
        echo "Warning! This will remove old generations of your system."
        read -p "How many generations to keep (default: all)? " keep_count

        if [ -z "$keep_count" ]; then
          read -p "This will remove all but the current generation. Continue (y/N)? " -n 1 -r
          echo
          if [[ $REPLY =~ ^[Yy]$ ]]; then
            nh clean all -v
          else
            echo "Cleanup cancelled."
          fi
        else
          read -p "This will keep the last $keep_count generations. Continue (y/N)? " -n 1 -r
          echo
          if [[ $REPLY =~ ^[Yy]$ ]]; then
            nh clean all -k "$keep_count" -v
          else
            echo "Cleanup cancelled."
          fi
        fi

        LOG_DIR="$HOME/ncli-cleanup-logs"
        mkdir -p "$LOG_DIR"
        LOG_FILE="$LOG_DIR/ncli-cleanup-$(date +%Y-%m-%d_%H-%M-%S).log"
        echo "Cleaning up old log files..." >> "$LOG_FILE"
        find "$LOG_DIR" -type f -mtime +3 -name "*.log" -delete >> "$LOG_FILE" 2>&1
        echo "Cleanup process logged to $LOG_FILE"
        ;;
      diag)
        echo "Generating system diagnostic report..."
        {
          echo "=== NixOS System Diagnostic Report ==="
          echo "Generated: $(date)"
          echo "Host: $HOST"
          echo "Hostname: $(hostname)"
          echo ""
          echo "=== System Information ==="
          inxi --full 2>/dev/null || echo "inxi not available"
          echo ""
          echo "=== Git Status ==="
          cd "$HOME/$PROJECT" 2>/dev/null && git status 2>/dev/null || echo "Git status not available"
          echo ""
          echo "=== Available Hosts ==="
          list_available_hosts 2>/dev/null || echo "Could not list hosts"
        } > "$HOME/diag.txt"
        echo "Diagnostic report saved to $HOME/diag.txt"
        ;;
      help)
        print_help
        ;;
      list-gens)
        echo "--- User Generations ---"
        nix-env --list-generations | cat || echo "Could not list user generations."
        echo ""
        echo "--- System Generations ---"
        nix profile history --profile /nix/var/nix/profiles/system | cat || echo "Could not list system generations."
        ;;
      list-hosts)
        list_available_hosts
        ;;
      rebuild)
        handle_backups
        echo "Starting NixOS rebuild for current host: $HOST"
        cd "$HOME/$PROJECT" || { echo "Error: Could not change to $HOME/$PROJECT"; exit 1; }
        if sudo nixos-rebuild switch --flake ".#$HOST"; then
          echo "✓ Rebuild finished successfully for $HOST"
        else
          echo "✗ Rebuild failed for $HOST" >&2
          exit 1
        fi
        ;;
      rebuild-boot)
        handle_backups
        echo "Starting NixOS rebuild with boot option for current host: $HOST"
        cd "$HOME/$PROJECT" || { echo "Error: Could not change to $HOME/$PROJECT"; exit 1; }
        if sudo nixos-rebuild boot --flake ".#$HOST"; then
          echo "✓ Rebuild with boot option finished successfully for $HOST"
          echo "Changes will activate on next restart"
        else
          echo "✗ Rebuild with boot option failed for $HOST" >&2
          exit 1
        fi
        ;;
      update)
        handle_backups
        echo "Updating flake and rebuilding system for current host: $HOST"
        cd "$HOME/$PROJECT" || { echo "Error: Could not change to $HOME/$PROJECT"; exit 1; }

        echo "Updating flake..."
        if nix flake update; then
          echo "✓ Flake updated successfully"
        else
          echo "✗ Flake update failed" >&2
          exit 1
        fi

        echo "Rebuilding system..."
        if sudo nixos-rebuild switch --flake ".#$HOST"; then
          echo "✓ Update and rebuild finished successfully for $HOST"
        else
          echo "✗ Update and rebuild failed for $HOST" >&2
          exit 1
        fi
        ;;
      build)
        if [ "$#" -lt 2 ]; then
          echo "Usage: ncli build <hostname>" >&2
          list_available_hosts
          exit 1
        fi
        build_host "$2"
        ;;
      deploy)
        if [ "$#" -lt 2 ]; then
          echo "Usage: ncli deploy <hostname>" >&2
          list_available_hosts
          exit 1
        fi
        deploy_host "$2"
        ;;
      switch-host)
        if [ -f "$HOME/$PROJECT/switch-host.sh" ]; then
          cd "$HOME/$PROJECT" && ./switch-host.sh
        else
          echo "Error: switch-host.sh not found in $HOME/$PROJECT" >&2
          exit 1
        fi
        ;;
      commit)
        cd "$HOME/$PROJECT" || { echo "Error: Could not change to $HOME/$PROJECT"; exit 1; }
        if [ "$#" -lt 2 ]; then
          read -p "Enter commit message: " commit_msg
        else
          shift
          commit_msg="$*"
        fi

        if [ -z "$commit_msg" ]; then
          echo "Error: Commit message cannot be empty" >&2
          exit 1
        fi

        git add -A && git commit -m "$commit_msg"
        ;;
      push)
        cd "$HOME/$PROJECT" || { echo "Error: Could not change to $HOME/$PROJECT"; exit 1; }
        git push origin $(git branch --show-current)
        ;;
      pull)
        cd "$HOME/$PROJECT" || { echo "Error: Could not change to $HOME/$PROJECT"; exit 1; }
        git pull origin $(git branch --show-current)
        ;;
      status)
        cd "$HOME/$PROJECT" || { echo "Error: Could not change to $HOME/$PROJECT"; exit 1; }
        git status
        ;;
      trim)
        echo "Running 'sudo fstrim -v /' may take a few minutes and impact system performance."
        read -p "Enter (y/Y) to run now or enter to exit (y/N): " -n 1 -r
        echo # move to a new line
        if [[ $REPLY =~ ^[Yy]$ ]]; then
          echo "Running fstrim..."
          sudo fstrim -v /
          echo "fstrim complete."
        else
          echo "Trim operation cancelled."
        fi
        ;;
      *)
        echo "Error: Invalid command '$1'" >&2
        print_help
        exit 1
        ;;
    esac
  ''