/**
 * Unit tests for src/live/auth.ts — Cookie auth handshake.
 *
 * All Directus HTTP calls are intercepted by mocking globalThis.fetch.
 * No real network calls.
 *
 * Covers:
 *  - 200 + valid user payload → returns parsed AuthenticatedUser.
 *  - 401 → returns null and increments `unauthorized` counter.
 *  - 403 → returns null and increments `unauthorized` counter.
 *  - Non-2xx (500) → returns null and increments `error` counter.
 *  - Network error (fetch throws) → returns null and increments `error` counter.
 *  - AbortError (timeout) → returns null and increments `error` counter.
 *  - 200 but missing `data` field → returns null and increments `error` counter.
 *  - 200 with `data: null` (expired session) → returns null and increments `unauthorized`.
 *  - 200 but user object missing `id` → returns null and increments `error`.
 *  - Empty cookie header → returns null immediately (no fetch call).
 *  - Auth latency histogram is observed on success.
 */

import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
import type { Logger } from 'pino';
import type { Config } from '../src/config/load.js';
import type { Metrics } from '../src/core/types.js';
import { createAuthClient } from '../src/live/auth.js';

// ---------------------------------------------------------------------------
// Helpers
// ---------------------------------------------------------------------------

function makeSilentLogger(): Logger {
  return {
    debug: vi.fn(),
    info: vi.fn(),
    warn: vi.fn(),
    error: vi.fn(),
    fatal: vi.fn(),
    trace: vi.fn(),
    child: vi.fn().mockReturnThis(),
    level: 'silent',
    silent: vi.fn(),
  } as unknown as Logger;
}

type TestMetrics = Metrics & {
  readonly incCalls: Array<{ name: string; labels?: Record<string, string> }>;
  readonly observeCalls: Array<{ name: string; value: number }>;
};

function makeMetrics(): TestMetrics {
  const incCalls: Array<{ name: string; labels?: Record<string, string> }> = [];
  const observeCalls: Array<{ name: string; value: number }> = [];
  return {
    incCalls,
    observeCalls,
    inc(name, labels) { incCalls.push({ name, labels }); },
    observe(name, value) { observeCalls.push({ name, value }); },
  };
}

function makeConfig(overrides: Partial<Config> = {}): Config {
  return {
    NODE_ENV: 'test',
    INSTANCE_ID: 'test-1',
    LOG_LEVEL: 'silent',
    REDIS_URL: 'redis://localhost:6379',
    POSTGRES_URL: 'postgres://localhost:5432/test',
    REDIS_TELEMETRY_STREAM: 'telemetry:t',
    REDIS_CONSUMER_GROUP: 'processor',
    REDIS_CONSUMER_NAME: 'test-consumer',
    METRICS_PORT: 0,
    BATCH_SIZE: 100,
    BATCH_BLOCK_MS: 500,
    WRITE_BATCH_SIZE: 50,
    DEVICE_STATE_LRU_CAP: 10_000,
    LIVE_WS_PORT: 8081,
    LIVE_WS_HOST: '0.0.0.0',
    LIVE_WS_PING_INTERVAL_MS: 30_000,
    LIVE_WS_DRAIN_TIMEOUT_MS: 5_000,
    LIVE_WS_BACKPRESSURE_THRESHOLD_BYTES: 1_048_576,
    DIRECTUS_BASE_URL: 'http://directus.test',
    DIRECTUS_AUTH_TIMEOUT_MS: 5_000,
    DIRECTUS_AUTHZ_TIMEOUT_MS: 5_000,
    LIVE_BROADCAST_GROUP_PREFIX: 'live-broadcast',
    LIVE_BROADCAST_BATCH_SIZE: 100,
    LIVE_BROADCAST_BATCH_BLOCK_MS: 1_000,
    LIVE_DEVICE_EVENT_REFRESH_MS: 30_000,
    ...overrides,
  };
}

const VALID_USER = {
  id: 'ada60b3d-b29f-4017-b702-cd6b700f9f6c',
  email: 'driver@example.com',
  role: 'f6114c7e-1e94-488a-93c3-41060fcb06bc',
  first_name: 'Test',
  last_name: 'User',
};

function makeOkFetch(data: unknown): typeof fetch {
  return vi.fn().mockResolvedValue({
    status: 200,
    ok: true,
    json: () => Promise.resolve({ data }),
  } as unknown as Response);
}

function makeStatusFetch(status: number): typeof fetch {
  return vi.fn().mockResolvedValue({
    status,
    ok: status >= 200 && status < 300,
    json: () => Promise.resolve({}),
  } as unknown as Response);
}

// ---------------------------------------------------------------------------
// Tests
// ---------------------------------------------------------------------------

describe('createAuthClient.validate', () => {
  let metrics: TestMetrics;
  let logger: Logger;
  let originalFetch: typeof globalThis.fetch;

  beforeEach(() => {
    metrics = makeMetrics();
    logger = makeSilentLogger();
    originalFetch = globalThis.fetch;
  });

  afterEach(() => {
    globalThis.fetch = originalFetch;
    vi.restoreAllMocks();
  });

  it('returns the parsed user when Directus returns 200 with a valid user payload', async () => {
    globalThis.fetch = makeOkFetch(VALID_USER);
    const client = createAuthClient(makeConfig(), logger, metrics);
    const user = await client.validate('session=abc123');

    expect(user).not.toBeNull();
    expect(user!.id).toBe(VALID_USER.id);
    expect(user!.email).toBe(VALID_USER.email);

    const successCalls = metrics.incCalls.filter(
      (c) => c.name === 'processor_live_auth_attempts_total' && c.labels?.['result'] === 'success',
    );
    expect(successCalls).toHaveLength(1);
  });

  it('returns null and increments unauthorized counter on 401', async () => {
    globalThis.fetch = makeStatusFetch(401);
    const client = createAuthClient(makeConfig(), logger, metrics);
    const user = await client.validate('session=bad');

    expect(user).toBeNull();
    const unauthorizedCalls = metrics.incCalls.filter(
      (c) => c.name === 'processor_live_auth_attempts_total' && c.labels?.['result'] === 'unauthorized',
    );
    expect(unauthorizedCalls).toHaveLength(1);
  });

  it('returns null and increments unauthorized counter on 403', async () => {
    globalThis.fetch = makeStatusFetch(403);
    const client = createAuthClient(makeConfig(), logger, metrics);
    const user = await client.validate('session=forbidden');

    expect(user).toBeNull();
    const unauthorizedCalls = metrics.incCalls.filter(
      (c) => c.name === 'processor_live_auth_attempts_total' && c.labels?.['result'] === 'unauthorized',
    );
    expect(unauthorizedCalls).toHaveLength(1);
  });

  it('returns null and increments error counter on 500', async () => {
    globalThis.fetch = makeStatusFetch(500);
    const client = createAuthClient(makeConfig(), logger, metrics);
    const user = await client.validate('session=boom');

    expect(user).toBeNull();
    const errorCalls = metrics.incCalls.filter(
      (c) => c.name === 'processor_live_auth_attempts_total' && c.labels?.['result'] === 'error',
    );
    expect(errorCalls).toHaveLength(1);
  });

  it('returns null and increments error counter when fetch throws a network error', async () => {
    globalThis.fetch = vi.fn().mockRejectedValue(new Error('ECONNREFUSED'));
    const client = createAuthClient(makeConfig(), logger, metrics);
    const user = await client.validate('session=abc');

    expect(user).toBeNull();
    const errorCalls = metrics.incCalls.filter(
      (c) => c.name === 'processor_live_auth_attempts_total' && c.labels?.['result'] === 'error',
    );
    expect(errorCalls).toHaveLength(1);
  });

  it('returns null when fetch is aborted (simulated timeout)', async () => {
    const abortErr = new DOMException('The operation was aborted', 'AbortError');
    globalThis.fetch = vi.fn().mockRejectedValue(abortErr);
    const client = createAuthClient(makeConfig({ DIRECTUS_AUTH_TIMEOUT_MS: 50 }), logger, metrics);
    const user = await client.validate('session=slow');

    expect(user).toBeNull();
    const errorCalls = metrics.incCalls.filter(
      (c) => c.name === 'processor_live_auth_attempts_total' && c.labels?.['result'] === 'error',
    );
    expect(errorCalls).toHaveLength(1);
  });

  it('returns null and increments error counter when response body is missing data field', async () => {
    globalThis.fetch = vi.fn().mockResolvedValue({
      status: 200,
      ok: true,
      json: () => Promise.resolve({}), // no `data` key at all
    } as unknown as Response);
    const client = createAuthClient(makeConfig(), logger, metrics);
    const user = await client.validate('session=weird');

    expect(user).toBeNull();
    const errorCalls = metrics.incCalls.filter(
      (c) => c.name === 'processor_live_auth_attempts_total' && c.labels?.['result'] === 'error',
    );
    expect(errorCalls).toHaveLength(1);
  });

  it('returns null and increments unauthorized counter when data is null (expired session)', async () => {
    globalThis.fetch = makeOkFetch(null);
    const client = createAuthClient(makeConfig(), logger, metrics);
    const user = await client.validate('session=expired');

    expect(user).toBeNull();
    const unauthorizedCalls = metrics.incCalls.filter(
      (c) => c.name === 'processor_live_auth_attempts_total' && c.labels?.['result'] === 'unauthorized',
    );
    expect(unauthorizedCalls).toHaveLength(1);
  });

  it('returns null and increments error counter when user object is missing id', async () => {
    globalThis.fetch = makeOkFetch({ email: 'noId@example.com', role: null });
    const client = createAuthClient(makeConfig(), logger, metrics);
    const user = await client.validate('session=noid');

    expect(user).toBeNull();
    const errorCalls = metrics.incCalls.filter(
      (c) => c.name === 'processor_live_auth_attempts_total' && c.labels?.['result'] === 'error',
    );
    expect(errorCalls).toHaveLength(1);
  });

  it('returns null immediately for an empty cookie header without making a fetch call', async () => {
    const mockFetch = vi.fn();
    globalThis.fetch = mockFetch;
    const client = createAuthClient(makeConfig(), logger, metrics);
    const user = await client.validate('');

    expect(user).toBeNull();
    expect(mockFetch).not.toHaveBeenCalled();
  });

  it('observes auth latency on a successful call', async () => {
    globalThis.fetch = makeOkFetch(VALID_USER);
    const client = createAuthClient(makeConfig(), logger, metrics);
    await client.validate('session=ok');

    const latencyCalls = metrics.observeCalls.filter(
      (c) => c.name === 'processor_live_auth_latency_ms',
    );
    expect(latencyCalls.length).toBeGreaterThanOrEqual(1);
    expect(latencyCalls[0]!.value).toBeGreaterThanOrEqual(0);
  });
});