import { afterEach, describe, expect, it, vi } from "vitest";

import { TeamsHttpStream } from "./streaming-message.js";

async function flushStreamTimer(): Promise<void> {

await vi.advanceTimersByTimeAsync(1);

}

describe("TeamsHttpStream", () => {

afterEach(() => {

vi.useRealTimers();

});

it("sends first chunk as typing activity with streaminfo", async () => {

vi.useFakeTimers();

const sent: unknown[] = [];

const stream = new TeamsHttpStream({

sendActivity: vi.fn(async (activity) => {

sent.push(activity);

return { id: "stream-1" };

}),

throttleMs: 1,

});

// Enough text to pass MIN_INITIAL_CHARS threshold

stream.update("Hello, this is a test response that is long enough.");

// Wait for throttle to flush

await new Promise((r) => setTimeout(r, 700));

await flushStreamTimer();

expect(sent.length).toBeGreaterThanOrEqual(1);

const firstActivity = sent[0] as Record<string, unknown>;

});

it("sends final message activity on finalize", async () => {

vi.useFakeTimers();

const sent: unknown[] = [];

const stream = new TeamsHttpStream({

sendActivity: vi.fn(async (activity) => {

sent.push(activity);

return { id: "stream-1" };

}),

throttleMs: 1,

});

stream.update("Hello, this is a complete response for finalization testing.");

await new Promise((r) => setTimeout(r, 700));

await flushStreamTimer();

await stream.finalize();

});

it("does not send below MIN_INITIAL_CHARS", async () => {

vi.useFakeTimers();

const sendActivity = vi.fn(async () => ({ id: "x" }));

const stream = new TeamsHttpStream({ sendActivity });

const stream = new TeamsHttpStream({ sendActivity, throttleMs: 1 });

stream.update("Hi");

await new Promise((r) => setTimeout(r, 700));

await flushStreamTimer();

expect(sendActivity).not.toHaveBeenCalled();

});

});

it("sets feedbackLoopEnabled on final message", async () => {

vi.useFakeTimers();

const sent: unknown[] = [];

const stream = new TeamsHttpStream({

sendActivity: vi.fn(async (activity) => {

sent.push(activity);

return { id: "stream-1" };

}),

feedbackLoopEnabled: true,

throttleMs: 1,

});

stream.update("A response long enough to pass the minimum character threshold for streaming.");

await new Promise((r) => setTimeout(r, 700));

await flushStreamTimer();

await stream.finalize();

const finalActivity = sent.find(

});

it("informative update establishes streamId for subsequent chunks", async () => {

vi.useFakeTimers();

const sent: unknown[] = [];

const stream = new TeamsHttpStream({

sendActivity: vi.fn(async (activity) => {

sent.push(activity);

return { id: "stream-1" };

}),

throttleMs: 1,

});

await stream.sendInformativeUpdate("Working...");

stream.update("Hello, this is a long enough response for streaming to begin.");

await new Promise((r) => setTimeout(r, 1600));

await flushStreamTimer();

// Second activity (streaming chunk) should have the streamId from the informative update

expect(sent.length).toBeGreaterThanOrEqual(2);