import { expect } from '@playwright/test';
import { test, type Client } from '../../fixtures/multi-client';
import {
  forceRelayOnlyIce,
  getRelayIceConfigs,
  seedTurnOnlyIceServers,
  waitForRelayedCandidatePairs,
  type TurnCredentials
} from '../../helpers/turn-relay';
import {
  isDockerAvailable,
  startTurnServer,
  type TurnServerHandle
} from '../../helpers/turn-server';
import { installDeterministicVoiceSettings } from '../../helpers/voice-session';
import {
  installAutoResumeAudioContext,
  installWebRTCTracking,
  waitForAllPeerAudioFlow,
  waitForAudioStatsPresent,
  waitForConnectedPeerCount,
  waitForOpenDataChannelCount
} from '../../helpers/webrtc-helpers';
import { ChatRoomPage } from '../../pages/chat-room.page';
import { RegisterPage } from '../../pages/register.page';
import { ServerSearchPage } from '../../pages/server-search.page';

const USER_PASSWORD = 'TestPass123!';
const VOICE_CHANNEL = 'General';

/**
 * Symmetric NAT gives a browser no usable direct path, so the whole call has to
 * ride a TURN relay. `iceTransportPolicy: 'relay'` reproduces that without any
 * network trickery: host and server-reflexive candidates are thrown away, and
 * only the TURN server the app was configured with is left.
 */
test.describe('Relay-only voice', () => {
  let turnServer: TurnServerHandle | null = null;

  test.beforeAll(async () => {
    if (!await isDockerAvailable()) {
      return;
    }

    turnServer = await startTurnServer();
  });

  test.afterAll(async () => {
    await turnServer?.stop();
    turnServer = null;
  });

  test('two users hear each other with every direct path removed', async ({ createClient }) => {
    test.skip(!turnServer, 'Relay-only voice needs Docker to run a local coturn.');
    test.setTimeout(240_000);

    const turn = turnServer as TurnServerHandle;
    const clients = await createRelayOnlyVoicePair(createClient, turn, `Relay Only Voice ${Date.now()}`);

    await test.step('Both ends settled on a TURN relay, not a direct path', async () => {
      for (const client of clients) {
        const pairs = await waitForRelayedCandidatePairs(client.page, 1, 60_000);

        // A direct pair here would mean the policy leaked and the test proved nothing.
        for (const pair of pairs) {
          expect(pair.localCandidateType, 'a peer connection escaped the relay-only policy').toBe('relay');
        }
      }
    });

    await test.step('Audio flows both ways through the relay', async () => {
      for (const client of clients) {
        await waitForAllPeerAudioFlow(client.page, 1, 60_000);
      }
    });
  });
});

async function createRelayOnlyVoicePair(
  createClient: () => Promise<Client>,
  turn: TurnCredentials,
  serverName: string
): Promise<Client[]> {
  const clients: Client[] = [];
  const credentials: { username: string; displayName: string }[] = [];

  for (let index = 0; index < 2; index++) {
    const client = await createClient();

    await installDeterministicVoiceSettings(client.page);
    await installWebRTCTracking(client.page);
    await forceRelayOnlyIce(client.page);
    await seedTurnOnlyIceServers(client.page, turn);
    await installAutoResumeAudioContext(client.page);

    clients.push(client);
    credentials.push({
      displayName: `Relay Voice ${index + 1}`,
      username: `relay_voice_${Date.now()}_${index + 1}`
    });
  }

  await test.step('Register both clients', async () => {
    for (const [index, client] of clients.entries()) {
      const registerPage = new RegisterPage(client.page);

      await registerPage.goto();
      await registerPage.register(
        credentials[index].username,
        credentials[index].displayName,
        USER_PASSWORD
      );

      await expect(client.page).toHaveURL(/\/dashboard/, { timeout: 20_000 });
    }
  });

  await test.step('Create and join the server', async () => {
    await new ServerSearchPage(clients[0].page).createServer(serverName, {
      description: 'Relay-only voice test'
    });

    await expect(clients[0].page).toHaveURL(/\/room\//, { timeout: 20_000 });

    await new ServerSearchPage(clients[1].page).joinServerFromSearch(serverName);
    await expect(clients[1].page).toHaveURL(/\/room\//, { timeout: 20_000 });
  });

  await test.step('Join both clients to voice', async () => {
    await new ChatRoomPage(clients[0].page).ensureVoiceChannelExists(VOICE_CHANNEL);

    for (const client of clients) {
      const room = new ChatRoomPage(client.page);

      await room.joinVoiceChannel(VOICE_CHANNEL);
      await expect(room.voiceControls).toBeVisible({ timeout: 20_000 });
    }

    for (const [index, client] of clients.entries()) {
      try {
        await waitForConnectedPeerCount(client.page, 1, 90_000);
        await waitForOpenDataChannelCount(client.page, 1, 90_000);
        await waitForAudioStatsPresent(client.page, 30_000);
      } catch (error) {
        // No TURN server in the config looks exactly like a failed relay from the
        // outside, so show what the app actually handed to WebRTC.
        const configs = await getRelayIceConfigs(client.page);

        console.log(`[relay client ${index + 1} ice configs] ${JSON.stringify(configs.slice(0, 3))}`);
        throw error;
      }
    }
  });

  return clients;
}