// lavinmq's provisioner — the adapter that makes lavinmq a provider of the mesh `amqp` interface.
// The reconcile loop, the contributions file, and reading the mesh's minted password are the sdk
// harness's; this writes only the per-service half: how lavinmq creates and removes a consumer's own
// broker (novox/hq ADR 0039/0040/0048).
//
// The `amqp` interface: a consumer connects as `as` with the password the mesh minted, to a vhost
// named for that same login — its own message broker, isolated from every other consumer's by the
// vhost boundary. It is a broker of its own, not a shared account on the mesh's control-plane broker.
//
// **The login and password are the mesh's, not the provisioner's (novox/hq ADR 0048).** The mesh
// derives the login and hands it to both ends so they agree, and mints the password and delivers a
// copy to each. lavinmq creates exactly that user with exactly that password — a name or password the
// provisioner invented is one the consumer could never present.
//
// Vhost-per-login is the isolation model, the exact analog of postgres's database-per-login: the
// consumer owns one vhost, named for its login, and a user with full rights on that vhost and no
// rights anywhere else. lavinmq enforces it — a user with no permission on `/` is refused the moment
// it opens that vhost (`NOT_ALLOWED`), so a login is a broker the consumer alone can reach.

import { runProvisioner, type Provision } from "@novox/mesh-sdk/provisioner";
import { emit } from "@novox/mesh-sdk/events";
import { LavinmqClient } from "../client.js";

const lavinmq = LavinmqClient.fromEnv();

/** Emit a lifecycle event without letting a broker hiccup fail the provisioning itself. */
async function announce(type: string, body: Record<string, string>): Promise<void> {
  try {
    await emit(type, body);
  } catch (err) {
    console.error(`[provisioner:amqp] emit ${type} failed: ${err}`);
  }
}

runProvisioner("amqp", {
  async create(p: Provision): Promise<void> {
    // The vhost and the user share the consumer's login, so one cannot reach another's broker.
    await lavinmq.waitReady();
    await lavinmq.createConsumer(p.as, p.password);
    await announce("module.lavinmq.amqp.provisioned", {
      consumer: p.consumer ?? "",
      user: p.as,
      vhost: p.as,
    });
  },

  async remove(p: { as: string }): Promise<void> {
    await lavinmq.removeConsumer(p.as);
    await announce("module.lavinmq.amqp.deprovisioned", { user: p.as, vhost: p.as });
  },
  // Asked every minute by the harness: whether the backend still holds this consumer exactly as
  // the mesh gave it, so a login lost behind the provisioner's back is made again (novox/hq issue 120).
  async holds(p: Provision): Promise<boolean> {
    return lavinmq.holdsConsumer(p.as, p.password);
  },
});