import { expect } from '@playwright/test';
import { test, type Client } from '../../fixtures/multi-client';
import { expectDashboardReady } from '../../helpers/dashboard';
import {
  countCreatedPeerConnections,
  expectExactlyOneInitiatorPerPair,
  readPeerRoleEdges,
  type PeerRoleEdge
} from '../../helpers/peer-role';
import { installTestServerEndpoints, type SeededEndpointInput } from '../../helpers/seed-test-endpoint';
import { startTestServer } from '../../helpers/test-server';
import {
  installDeterministicVoiceSettings,
  joinRoomFromSearch,
  joinVoiceChannelUntilConnected,
  openSavedRoomByName
} from '../../helpers/voice-session';
import { waitForVoiceRosterCount } from '../../helpers/voice-roster';
import {
  dumpRtcDiagnostics,
  installAutoResumeAudioContext,
  installWebRTCTracking,
  waitForAllPeerAudioFlow,
  waitForAudioStatsPresent,
  waitForPeerConnected
} 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 SIGNAL_A_ID = 'e2e-cross-signal-a';
const SIGNAL_B_ID = 'e2e-cross-signal-b';
const VOICE_CHANNEL = 'General';
const USER_PASSWORD = 'TestPass123!';
const USER_COUNT = 4;
const EXPECTED_REMOTE_PEERS = USER_COUNT - 1;

interface TestUser {
  username: string;
  displayName: string;
  /** Signal server this human registered on - their home identity space. */
  homeSignalId: string;
}

type TestClient = Client & { user: TestUser };

test.describe('Cross-signal WebRTC identity', () => {
  test.describe.configure({ timeout: 600_000 });

  test('elects exactly one initiator per pair when peers have different home signal servers', async ({
    createClient,
    testServer
  }) => {
    const signalB = await startTestServer();

    try {
      const suffix = `cross_signal_${Date.now()}`;
      const roomName = `Cross Signal Voice ${suffix}`;
      const endpoints: SeededEndpointInput[] = [
        {
          id: SIGNAL_A_ID,
          name: 'E2E Signal A',
          url: testServer.url,
          isActive: true,
          status: 'online'
        },
        {
          id: SIGNAL_B_ID,
          name: 'E2E Signal B',
          url: signalB.url,
          isActive: true,
          status: 'online'
        }
      ];
      // The room is hosted on signal B. Two humans are at home there and two are
      // foreign guests, so most pairs must compare a foreign actor id against a
      // foreign actor id - never a home id against one.
      const users: TestUser[] = [
        { username: `host_${suffix}`, displayName: 'Cross Host', homeSignalId: SIGNAL_B_ID },
        { username: `native_${suffix}`, displayName: 'Cross Native', homeSignalId: SIGNAL_B_ID },
        { username: `guest_a_${suffix}`, displayName: 'Cross Guest A', homeSignalId: SIGNAL_A_ID },
        { username: `guest_b_${suffix}`, displayName: 'Cross Guest B', homeSignalId: SIGNAL_A_ID }
      ];
      const clients: TestClient[] = [];

      for (const user of users) {
        const client = await createClient();

        await installTestServerEndpoints(client.context, endpoints);
        await installDeterministicVoiceSettings(client.page);
        await installWebRTCTracking(client.context);
        await installAutoResumeAudioContext(client.page);

        clients.push({ ...client, user });
      }

      const [host] = clients;

      await test.step('Each human registers on their own home signal server', async () => {
        for (const client of clients) {
          const register = new RegisterPage(client.page);

          await register.goto();
          await register.serverSelect.selectOption(client.user.homeSignalId);
          await register.register(client.user.username, client.user.displayName, USER_PASSWORD);
          await expectDashboardReady(client.page);
        }
      });

      await test.step('The host creates the voice room on signal B', async () => {
        await new ServerSearchPage(host.page).createServer(roomName, {
          description: 'Cross-signal initiator election coverage',
          sourceId: SIGNAL_B_ID
        });

        await expect(host.page).toHaveURL(/\/room\//, { timeout: 20_000 });
        await new ChatRoomPage(host.page).ensureVoiceChannelExists(VOICE_CHANNEL);
      });

      await test.step('Everyone else joins the room, provisioning a foreign account when needed', async () => {
        for (const client of clients.slice(1)) {
          await joinRoomFromSearch(client.page, roomName);
        }

        await openSavedRoomByName(host.page, roomName);
      });

      // Everyone reconnects at once, so every pair elects its initiator from the same
      // roster snapshot. Staggered arrivals let one side's 1s fallback-offer timer
      // serialize negotiation, which hides a wrong comparison; a reconnect storm - a
      // signal blip, or a channel everyone piles into - does not.
      await test.step('All four reconnect simultaneously', async () => {
        await Promise.all(clients.map(async (client) => {
          await client.page.reload({ waitUntil: 'domcontentloaded' });
          await openSavedRoomByName(client.page, roomName);
        }));
      });

      await test.step('All four join the same voice channel simultaneously', async () => {
        await Promise.all(clients.map((client) =>
          joinVoiceChannelUntilConnected(client.page, VOICE_CHANNEL)
        ));

        for (const client of clients) {
          await waitForVoiceRosterCount(client.page, VOICE_CHANNEL, USER_COUNT);
        }
      });

      await test.step('Every pair carries bidirectional audio', async () => {
        await Promise.all(clients.map((client) => waitForPeerConnected(client.page, 90_000)));
        await Promise.all(clients.map((client) => waitForAudioStatsPresent(client.page, 30_000)));

        for (const client of clients) {
          try {
            await waitForAllPeerAudioFlow(client.page, EXPECTED_REMOTE_PEERS, 120_000);
          } catch (error) {
            console.log(`[${client.user.displayName} RTC]\n${await dumpRtcDiagnostics(client.page)}`);
            throw error;
          }
        }
      });

      await test.step('Exactly one side of every pair elected itself initiator', async () => {
        const edgesByClient: Record<string, PeerRoleEdge[]> = {};

        for (const client of clients) {
          edgesByClient[client.user.displayName] = (await readPeerRoleEdges(client.page))
            .filter((edge) => edge.connectionState === 'connected');
        }

        // Comparing a home id against a foreign actor id is not antisymmetric, so both
        // peers could offer (glare) or neither could until a takeover timer fired.
        expectExactlyOneInitiatorPerPair(edgesByClient);
      });

      await test.step('No peer had to be rebuilt to reach that state', async () => {
        for (const client of clients) {
          expect(
            await countCreatedPeerConnections(client.page),
            `${client.user.displayName} rebuilt a peer connection instead of connecting on the first offer`
          ).toBe(EXPECTED_REMOTE_PEERS);
        }
      });
    } finally {
      await signalB.stop();
    }
  });
});