# Migration shim for `services.hyperhive.swarm.peers`, replaced by the
# `swarm.hives` directory in ./swarm.nix.
#
# ⚠️ This could not be a `mkRenamedOptionModule`. `hives` is not `peers`
# under a new name, it is **`peers` ∪ {self}**: the set gains a member no
# existing config has ever written down, because a host's own identity
# lived in *other* options entirely. A rename migrates a name and a
# default can re-root a meaning; neither can conjure a new member.
#
# The whole module is self-contained and deletable — one file to remove
# when the deprecation window closes, with nothing else referring to it.
#
# Deliberately a warning rather than a hard failure, with the loudness
# coming from elsewhere: a config that set only `peers` leaves `hives`
# empty, so the self-entry assertion in ./swarm.nix fails the build
# anyway. The warning is what explains it; the assertion is what stops
# it.
{
  lib,
  config,
  ...
}:
let
  peers = config.services.hyperhive.swarm.peers;
  withCaCert = lib.attrNames (lib.filterAttrs (_: p: p ? caCert && p.caCert != null) peers);
in
{
  options.services.hyperhive.swarm.peers = lib.mkOption {
    type = lib.types.attrsOf lib.types.anything;
    default = { };
    visible = false;
    internal = true;
    description = ''
      Removed — use `services.hyperhive.swarm.hives` instead, which
      describes every hive in the swarm including this one. Kept only so
      an existing definition produces a warning that says where to move
      it, rather than an "option does not exist" error that says nothing.
    '';
  };

  config.warnings =
    lib.optional (peers != { }) ''
      services.hyperhive.swarm.peers is removed and ignored. Move these
      entries to services.hyperhive.swarm.hives, keyed by hive NAME
      rather than domain, and add an entry for this hive itself
      (services.hyperhive.hiveName) — `hives` is the swarm's full
      directory, identical on every host.

        services.hyperhive.swarm.hives.<name> = {
          domain = "<the old attrset key>";
          # wireguard* carries over unchanged
        };

      Still set: ${lib.concatStringsSep ", " (lib.attrNames peers)}
    ''
    ++ lib.optional (withCaCert != [ ]) ''
      services.hyperhive.swarm.peers.<hive>.caCert is removed and
      ignored, and has no replacement in services.hyperhive.swarm.hives.

      Trust inside a swarm now derives from the swarm root CA
      (services.hyperhive.swarm.ca — see docs/swarm/ca.md): every hive
      under it chains to it, so a per-hive CA is dead weight. What this
      genuinely drops is trusting a hive whose root this swarm does NOT
      own — another swarm's, or one keeping its own CA.

      Still set on: ${lib.concatStringsSep ", " withCaCert}
    '';
}