// A host with several routes connects through the first one that answers.
import { afterEach, describe, expect, it } from "bun:test";
import type { Server } from "bun";

import { T3Host } from "../src/t3/host.ts";

const ENVIRONMENT_ID = "env-laptop";
let server: Server<undefined> | undefined;
afterEach(() => server?.stop(true));

/** Just enough of a T3 server: the descriptor, a ticket, config, and an empty shell snapshot. */
function fakeT3() {
  server = Bun.serve({
    port: 0,
    fetch(req, srv) {
      const { pathname } = new URL(req.url);
      if (pathname === "/.well-known/t3/environment") {
        return Response.json({ environmentId: ENVIRONMENT_ID, label: "framework-gib", serverVersion: "0.1.5", orchestrationProtocolVersion: 2 });
      }
      if (pathname === "/api/auth/websocket-ticket/rpc") return Response.json({ ticket: "t" });
      if (pathname === "/ws" && srv.upgrade(req)) return undefined;
      return new Response("not found", { status: 404 });
    },
    websocket: {
      message(ws, data) {
        const frame = JSON.parse(String(data)) as { _tag: string; id: string; tag: string };
        if (frame._tag !== "Request") return;
        if (frame.tag === "server.getConfig") {
          ws.send(JSON.stringify({ _tag: "Exit", requestId: frame.id, exit: { _tag: "Success", value: {} } }));
        } else if (frame.tag === "orchestration.subscribeShell") {
          const snapshot = { snapshotSequence: 1, projects: [], threads: [] };
          ws.send(JSON.stringify({ _tag: "Chunk", requestId: frame.id, values: [{ kind: "snapshot", snapshot }] }));
        }
      },
    },
  });
  return `http://localhost:${server.port}`;
}

describe("T3Host routes", () => {
  it("falls back to the next route when the preferred one does not answer", async () => {
    const working = fakeT3();
    // Port 9 (discard) refuses connections, standing in for a LAN route that is down.
    const host = new T3Host({ id: ENVIRONMENT_ID, label: "Laptop", urls: ["http://127.0.0.1:9", working], token: "x", environmentId: ENVIRONMENT_ID });
    const online = new Promise<void>((resolve) => {
      const check = setInterval(() => {
        if (host.status === "online") {
          clearInterval(check);
          resolve();
        }
      }, 5);
    });
    host.start();
    await online;
    expect(host.url).toBe(working);
    host.stop();
  });
});