# treefmt config, evaluated per-system in flake.nix and exposed as
# `nix fmt` (the formatter) plus a `nix flake check` formatting gate.
{ ... }:
{
  projectRootFile = "flake.nix";

  programs = {
    nixfmt.enable = true;
    prettier.enable = true;
    yamlfmt.enable = true;
    shfmt.enable = true;
  };

  settings = {
    on-unmatched = "fatal";
    global.excludes = [
      # Secrets and clan-managed state — never reformat.
      "sops/*"
      "vars/*"
      "inventory.json"

      # Generated — don't reformat (regeneration would churn the diff).
      "*facter.json"

      # No formatter, or reformatting would corrupt them.
      "*.zone" # Knot zone files
      "flake.lock"
      ".envrc"
      ".gitignore"
    ];
  };
}