import { describe, test, expect, vi, beforeEach, afterEach } from 'vitest';
import { AudioEngine } from '../src/lib/audio/AudioEngine.svelte';
import { UserSettingsStore } from '../src/lib/stores/UserSettingsStore.svelte';
import type { Scenario } from '../types';

describe('AudioEngine Reactive Controller', () => {
  const mockScenario: Scenario = {
    id: 'test-s1',
    title: 'Silent Friend',
    description: 'Friend has not replied to your text',
    category: 'Relationships',
    difficulty: 'Beginner',
    systemInstruction: 'INTERNAL CBT LOGIC: You were just busy.',
    initialMessage: 'Hey, sorry I was swamped yesterday.',
    cbtFocus: ['Mind Reading'],
    characterName: 'Sam'
  };

  let mockAudioContext: any;
  let mockUserMediaStream: any;

  beforeEach(() => {
    mockAudioContext = {
      state: 'running',
      destination: {},
      createAnalyser: () => ({
        fftSize: 256,
        frequencyBinCount: 128,
        getByteFrequencyData: (arr: Uint8Array) => arr.fill(50)
      }),
      createMediaStreamSource: () => ({
        connect: vi.fn()
      }),
      createBufferSource: () => ({
        buffer: null,
        connect: vi.fn(),
        start: vi.fn(),
        stop: vi.fn(),
        onended: null
      }),
      decodeAudioData: async () => ({
        duration: 2.0
      }),
      resume: vi.fn(),
      close: vi.fn()
    };

    mockUserMediaStream = {
      getTracks: () => [
        {
          stop: vi.fn()
        }
      ]
    };

    vi.stubGlobal('AudioContext', function () {
      return mockAudioContext;
    });

    vi.stubGlobal('navigator', {
      mediaDevices: {
        getUserMedia: async () => mockUserMediaStream,
        enumerateDevices: async () => []
      }
    });

    vi.stubGlobal('requestAnimationFrame', (cb: FrameRequestCallback) => 1);
    vi.stubGlobal('cancelAnimationFrame', vi.fn());
  });

  afterEach(() => {
    vi.restoreAllMocks();
  });

  test('AudioEngine reports error if OpenRouter API key is missing', async () => {
    const userSettings = new UserSettingsStore();
    userSettings.openRouterApiKey = '';

    const originalEnv = process.env.OPENROUTER_API_KEY;
    try {
      process.env.OPENROUTER_API_KEY = '';
      const engine = new AudioEngine(mockScenario, userSettings);
      await engine.start();

      expect(engine.status).toBe('error');
      expect(engine.errorMessage).toContain('OpenRouter API Key is missing');
    } finally {
      if (originalEnv !== undefined) process.env.OPENROUTER_API_KEY = originalEnv;
    }
  });

  test('AudioEngine initializes, starts, and loads initial greeting when API key is present', async () => {
    const userSettings = new UserSettingsStore();
    userSettings.openRouterApiKey = 'sk-or-v1-mock-valid-key';

    const engine = new AudioEngine(mockScenario, userSettings);
    // Mock speakText to avoid real network call
    engine.speakText = vi.fn();

    await engine.start();

    expect(engine.status).toBe('active');
    expect(engine.errorMessage).toBe(null);
    expect(engine.messages.length).toBe(1);
    expect(engine.messages[0].text).toBe(mockScenario.initialMessage);
    expect(engine.speakText).toHaveBeenCalledWith(mockScenario.initialMessage);

    engine.destroy();
  });

  test('toggleMute toggles isMuted state and stops audio', async () => {
    const userSettings = new UserSettingsStore();
    const engine = new AudioEngine(mockScenario, userSettings);

    expect(engine.isMuted).toBe(false);
    engine.toggleMute();
    expect(engine.isMuted).toBe(true);

    engine.toggleMute();
    expect(engine.isMuted).toBe(false);

    engine.destroy();
  });

  test('stopAllAudio resets AI speaking flags and cancels speech synthesis', () => {
    const cancelMock = vi.fn();
    vi.stubGlobal('speechSynthesis', {
      cancel: cancelMock,
      speak: vi.fn()
    });

    const userSettings = new UserSettingsStore();
    const engine = new AudioEngine(mockScenario, userSettings);
    engine.isAiSpeaking = true;
    engine.aiAudioLevel = 45;

    engine.stopAllAudio();

    expect(engine.isAiSpeaking).toBe(false);
    expect(engine.aiAudioLevel).toBe(0);
    expect(cancelMock).toHaveBeenCalled();

    engine.destroy();
  });

  test('activeLevel derived property reflects active speaker volume', () => {
    const userSettings = new UserSettingsStore();
    const engine = new AudioEngine(mockScenario, userSettings);

    engine.micLevel = 25;
    engine.aiAudioLevel = 60;

    engine.isAiSpeaking = false;
    expect(engine.activeLevel).toBe(25);

    engine.isAiSpeaking = true;
    expect(engine.activeLevel).toBe(60);

    engine.destroy();
  });
});