# Places operator-selected skills into Claude Code's skills directory, one per
# skill, for every project.
{
  config,
  lib,
  ...
}:
let
  cfg = config.programs.agents;
  claudeCode = config.programs.claude-code;
in
{
  options.programs.agents.skills = lib.mkOption {
    type = lib.types.listOf lib.types.package;
    default = [ ];
    example = lib.literalExpression "[ inputs.skills.packages.\${system}.some-skill ]";
    description = ''
      Skills to install globally, into the `skills/` subdirectory of
      {option}`programs.claude-code.configDir`, so they are active in every
      project.

      Selection is by derivation: pass skill derivations from the skills flake's
      `packages.<system>`, each of which carries its placement name as an
      eval-time attribute. An empty list installs nothing.

      Every skill is written as its own recursive {option}`home.file`, so this
      option composes with an operator's own {option}`programs.claude-code.skills`
      and with other modules placing skills under the same directory rather than
      claiming the tree. Placement is gated on
      {option}`programs.claude-code.enable`.
    '';
  };

  # `agents` is an umbrella namespace with no shared enable, so the skills
  # feature self-gates.
  # An empty list writes nothing, and files land only when Claude Code is
  # enabled.
  # Reading each skill's source realises its derivation, so gating on
  # `claude-code.enable` also keeps that realisation off a host that installs
  # nothing.
  config = lib.mkIf claudeCode.enable {
    # `configDir` comes from the Claude Code module, so skills land beside its
    # own wherever the operator points it.
    # Each name is the derivation's eval-time `skillName`, so placement reads no
    # `$out` and needs no import-from-derivation.
    # `recursive = true` materialises `skills/<name>/` as a directory of per-file
    # symlinks, which is what lets this module, the operator's own skills, and
    # self-placing tool modules share one `skills/` tree.
    #
    # This deliberately does not feed the single-valued
    # `programs.claude-code.skills`, which would collide with an operator already
    # setting it.
    home.file = lib.listToAttrs (
      map (skill: {
        name = "${claudeCode.configDir}/skills/${skill.skillName}";
        value = {
          source = skill;
          recursive = true;
        };
      }) cfg.skills
    );
  };
}