import { AuthStorage, type ExtensionAPI } from "@earendil-works/pi-coding-agent";
import { fetchInceptronModels } from "./discovery.js";
import { INCEPTRON_FALLBACK_MODELS } from "./models.js";

const DEFAULT_BASE_URL = "https://api.inceptron.io/v1";
const PROVIDER_ID = "inceptron";

/**
 * Resolve the discovery key from the same sources pi uses at request time,
 * in pi's precedence order: a stored credential (what `/login` writes to
 * auth.json, supporting `$env` / `!command` forms) wins over the plain
 * `INCEPTRON_API_KEY` env var.
 *
 * We can't simply call `AuthStorage.getApiKey(PROVIDER_ID)` and stop there: a
 * standalone AuthStorage only knows pi's built-in provider→env map (which has
 * no entry for our custom `inceptron` id) and lacks the model-registry fallback
 * resolver, so it would never see `INCEPTRON_API_KEY`. Hence the explicit env
 * fallback. Never throws — discovery is best-effort and must not block startup.
 */
async function resolveDiscoveryKey(): Promise<string | undefined> {
  try {
    const stored = await AuthStorage.create().getApiKey(PROVIDER_ID);
    if (stored) return stored;
  } catch {
    // Bad auth.json / failing `!command` — fall through to the env var.
  }
  return process.env.INCEPTRON_API_KEY?.trim() || undefined;
}

/**
 * pi extension: registers Inceptron (https://www.inceptron.io) as an LLM
 * provider. Inceptron exposes an OpenAI-compatible chat API, so we use pi's
 * built-in `openai-completions` transport and only supply registration,
 * credentials, and model metadata.
 *
 * The factory is async: when a key is resolvable (see {@link resolveDiscoveryKey})
 * we try to discover the live model list from `GET /v1/models`, falling back to
 * the curated catalog. pi awaits the async factory before provider registration,
 * so discovered models are available immediately without `/reload`.
 */
export default async function inceptron(pi: ExtensionAPI): Promise<void> {
  const baseUrl = process.env.INCEPTRON_BASE_URL?.trim() || DEFAULT_BASE_URL;

  // Resolve a key only to decide whether to attempt discovery. The provider is
  // always registered with the `$INCEPTRON_API_KEY` reference so pi's own
  // credential hierarchy (CLI flag → auth.json → env → models.json) still
  // applies at request time even if no key is resolvable right now. Resolving
  // from auth.json here (not just the env var) means a key saved via `/login`
  // also feeds discovery — including for `pi --list-models`, which runs this
  // factory but never starts an interactive session.
  const apiKey = await resolveDiscoveryKey();

  const discovered = apiKey ? await fetchInceptronModels(baseUrl, apiKey) : null;
  const models = discovered ?? INCEPTRON_FALLBACK_MODELS;

  pi.registerProvider(PROVIDER_ID, {
    name: "Inceptron",
    baseUrl,
    apiKey: "$INCEPTRON_API_KEY",
    api: "openai-completions",
    authHeader: true,
    models,
  });
}