{ config, lib, ... }:

# File-based override system for Nomarchy.
#
# When `nomarchy.overrides.enable = true` (default), every entry in
# `nomarchy.overrides.paths` substitutes the `xdg.configFile.<key>.source`
# Nomarchy ships by default. The substitution is done with `lib.mkForce`
# so it wins over Nomarchy's own `lib.mkDefault` writes. Other fields on
# the original entry (e.g. `recursive`) survive the merge.
#
# Usage in a downstream home.nix:
#
#   nomarchy.overrides.paths = {
#     "nomarchy/default/hypr/looknfeel.conf" = ./mine/looknfeel.conf;
#     "waybar/style.css"                     = ./mine/waybar.css;
#   };
#
# The keys are xdg.configFile paths (i.e. relative to ~/.config/). Drop-
# in-a-dir discovery is intentionally not supported — Nix needs every
# managed file declared at evaluation time, and the attrset is the
# explicit-config shape the rest of the Nomarchy module surface uses.

let
  cfg = config.nomarchy.overrides;
in
{
  options.nomarchy.overrides = {
    enable = lib.mkOption {
      type = lib.types.bool;
      default = true;
      description = ''
        Whether file-based overrides in nomarchy.overrides.paths are
        applied. Defaults to true so an empty `paths` is a no-op and
        a populated one Just Works without a second toggle.
      '';
    };

    paths = lib.mkOption {
      type = lib.types.attrsOf lib.types.path;
      default = {};
      example = lib.literalExpression ''
        {
          "nomarchy/default/hypr/looknfeel.conf" = ./looknfeel.conf;
          "waybar/style.css" = ./waybar.css;
        }
      '';
      description = ''
        Attribute set mapping xdg.configFile paths (relative to
        ~/.config/) to Nix paths whose contents should replace the
        Nomarchy-shipped source. Each entry deploys at lib.mkForce
        priority so it overrides Nomarchy's lib.mkDefault writes;
        recursive flags and other fields on the original entry are
        preserved. Pointing at a path Nomarchy doesn't manage just
        creates a new xdg.configFile entry.
      '';
    };
  };

  config = lib.mkIf cfg.enable {
    xdg.configFile = lib.mapAttrs (_path: src: {
      source = lib.mkForce src;
    }) cfg.paths;
  };
}