# `checks.module-eval-matrix-core` — see ./lib.nix for the shared
# rationale (why this suite exists, naming convention, "evaluates
# not executes").
{
  pkgs,
  lib,
  self,
  nixosSystem,
}:
let
  inherit
    (import ./lib.nix {
      inherit
        pkgs
        lib
        self
        nixosSystem
        ;
    })
    hive
    runGroup
    ;

  # A deliberately odd `maxRequestSize`, so the number the assertion looks for
  # cannot have come from a default or from another module's literal.
  matrixBodyCap = hive {
    deploy.singleHostSwarm = true;
    deploy.matrix.maxRequestSize = 99000000;
  };

  # The same hive with the identity taken away, which separates "a homeserver
  # is deployed" from "this host can authenticate to the store".
  matrixNoBaoIdentity = hive { deploy.matrix.enable = true; };

  # A hive host that does not run the homeserver: its hive-c0re reaches the
  # homeserver across the network.
  matrixElsewhere = hive { };
  cases = [
    {
      # Absence arm, and what makes the one above able to fail: with no leaf
      # this unit would fail a TLS handshake on every boot, so it must not
      # exist at all rather than retry its way through the start limit.
      name = "a hive with no store identity renders no queue credential reader";
      ok = !(matrixNoBaoIdentity.systemd.services ? swarm-bao-queue-agent);
    }
    {
      # Two limits governed a matrix upload and nothing kept them in agreement,
      # so raising the documented one past the gateway's hardcoded cap changed
      # nothing. The second clause is the control: the old directive is gone, so
      # a pass means the value is derived rather than that `hasInfix` matched
      # something incidental. It targets the whole directive rather than the
      # bare size, because the rendered config carries the comment above it and
      # a prose mention of the old value would defeat a looser arm.
      name = "the matrix gateway's body cap is derived from maxRequestSize, not a literal";
      ok =
        let
          c = matrixBodyCap.services.nginx.virtualHosts."chat.t.local".locations."/_matrix/".extraConfig;
        in
        lib.hasInfix "client_max_body_size 100048576;" c && !(lib.hasInfix "client_max_body_size 50M" c);
    }
    {
      # Absence arm. A hive with no client identity gets no
      # store environment at all — the daemon reports a queue it cannot serve
      # rather than a handshake it cannot explain.
      name = "a hive with no client identity gives hive-c0re no store environment";
      ok =
        let
          s = matrixNoBaoIdentity.systemd.services;
        in
        s ? hive-c0re
        && !(s.hive-c0re.environment ? BAO_ADDR)
        && !(lib.any (c: lib.hasPrefix "bao-" c) s.hive-c0re.serviceConfig.LoadCredential);
    }
    {
      # hive-c0re logs in with the hive's matrix token over this URL, and on a
      # host without the homeserver that login crosses the network, so the
      # default must be TLS all the way to the daemon's environment.
      name = "hive-c0re provisions matrix over https from a hive that does not run it";
      ok =
        !matrixElsewhere.services.hyperhive.deploy.matrix.enable
        && matrixElsewhere.services.hyperhive.swarm.matrix.apiUrl == "https://chat.t.local"
        &&
          matrixElsewhere.systemd.services.hive-c0re.environment.HIVE_MATRIX_API_URL
          == "https://chat.t.local";
    }
  ];
in
runGroup "matrix-core" cases