# The agents' toplevels as the controller's meta flake builds them, for the VM
# tests that deploy agents without network or a substituter (./full-setup.nix,
# ./semi-spread.nix). `hive-meta-flake/testdata/meta-flake-swarm.nix.in`, filled
# in with the controller's settings, is that flake: the toplevels are built from
# it here, so the builder finds them in its store. The builder's nix daemon runs
# with `max-jobs = 0`, so a missing toplevel fails the build instead of
# compiling.
{
  pkgs,
  self,
  agents,
}:
let
  inherit (pkgs) lib;

  inherit (import ./hyperhive-fixture-repo.nix { inherit pkgs self; }) hyperhiveRepo;

  metaTemplate = ../../hive-meta-flake/testdata/meta-flake-swarm.nix.in;

  # The values the fixture has a placeholder for. A swarm whose controller sends
  # another set renders another flake, so evaluation stops there.
  forwardedVars = [
    "HIVE_AGENT_BAO_ADDR"
    "HIVE_AGENT_BAO_SERVICES_PKI_MOUNT"
    "HIVE_AGENT_LOGS_QUERY_URL"
    "HIVE_AGENT_METRICS_URL"
    "HIVE_FORGE_URL"
    "HIVE_MATRIX_URL"
  ];

  # The meta flake the controller renders for `agents`, from its settings JSON
  # (`SWARM_CONTROLLER_META_FLAKE`). `hyperhive` is `self`: the agents' toplevels
  # do not depend on how the input is pinned.
  filled =
    settingsJson: pin:
    let
      settings = builtins.fromJSON settingsJson;
      names = [ "HYPERHIVE_URL" ] ++ forwardedVars;
      values = [ pin ] ++ map (name: settings.vars.${name}) forwardedVars;
    in
    assert lib.assertMsg
      (builtins.attrNames settings.vars == forwardedVars && !settings.github_disabled)
      "the controller's meta flake settings changed: update hive-meta-flake/testdata/meta-flake-swarm.nix.in";
    builtins.replaceStrings (map (name: "@${name}@") names) values (builtins.readFile metaTemplate);

  toplevels =
    settingsJson:
    let
      flake = import (builtins.toFile "meta-flake.nix" (filled settingsJson "unused"));
      evaluated = flake.outputs {
        self = null;
        hyperhive = self;
      };
    in
    map (agent: evaluated.nixosConfigurations.${agent}.config.system.build.toplevel) agents;
in
{
  inherit hyperhiveRepo metaTemplate toplevels;

  # What the builder's store needs besides the toplevels: every source tree the
  # meta flake's lock names, keyed by narHash (nix takes a locked input from the
  # store when its path is valid), and the repo the test pushes to the forge.
  sourcePaths = [
    self
    self.inputs.nixpkgs
    self.inputs.crane
    self.inputs.treefmt-nix
    hyperhiveRepo
  ];
}