// Sound service for chess UI

// Define sound types
type SoundType = 'move' | 'capture' | 'check' | 'castle' | 'game-end' | 'promote';

// Map of sound files
const SOUND_FILES: Record<SoundType, string> = {
  'move': '/assets/sounds/move.mp3',
  'capture': '/assets/sounds/capture.mp3',
  'check': '/assets/sounds/check.mp3',
  'castle': '/assets/sounds/castle.mp3',
  'game-end': '/assets/sounds/game-end.mp3',
  'promote': '/assets/sounds/move.mp3'  // Reusing move sound for promote
};

// Audio objects for preloading
const audioCache: Record<SoundType, HTMLAudioElement> = {} as Record<SoundType, HTMLAudioElement>;

// Sound enabled flag (can be toggled by user)
let soundEnabled = true;

// Create fallback sounds using the Web Audio API if sound files are not available
const audioContext = typeof AudioContext !== 'undefined' ? new AudioContext() : null;

// Function to create a simple beep sound
const createBeepSound = (frequency: number, duration: number): AudioBuffer | null => {
  if (!audioContext) return null;
  
  const sampleRate = audioContext.sampleRate;
  const buffer = audioContext.createBuffer(1, sampleRate * duration, sampleRate);
  const data = buffer.getChannelData(0);
  
  for (let i = 0; i < buffer.length; i++) {
    data[i] = Math.sin(2 * Math.PI * frequency * i / sampleRate) * 
              (i < buffer.length * 0.1 ? i / (buffer.length * 0.1) : 
               i > buffer.length * 0.9 ? (buffer.length - i) / (buffer.length * 0.1) : 1);
  }
  
  return buffer;
};

// Create fallback sounds
const fallbackSounds: Record<SoundType, AudioBuffer | null> = {
  'move': audioContext ? createBeepSound(440, 0.1) : null,  // A4 note
  'capture': audioContext ? createBeepSound(330, 0.2) : null, // E4 note
  'check': audioContext ? createBeepSound(587, 0.3) : null,  // D5 note
  'castle': audioContext ? createBeepSound(261, 0.3) : null, // C4 note
  'game-end': audioContext ? createBeepSound(196, 0.5) : null, // G3 note
  'promote': audioContext ? createBeepSound(523, 0.2) : null  // C5 note
};

/**
 * Preload all sound files
 */
export const preloadSounds = (): void => {
  Object.entries(SOUND_FILES).forEach(([key, file]) => {
    try {
      const audio = new Audio();
      audio.src = file;
      audio.preload = 'auto';
      audioCache[key as SoundType] = audio;
    } catch (error) {
      console.error(`Failed to preload sound: ${file}`, error);
    }
  });
};

/**
 * Play a sound effect
 * @param type The type of sound to play
 */
export const playSound = (type: SoundType): void => {
  if (!soundEnabled) return;
  
  try {
    // Try to play the audio file
    const audio = audioCache[type];
    if (audio) {
      audio.currentTime = 0;
      audio.play().catch(err => {
        console.warn('Error playing sound file, using fallback:', err);
        playFallbackSound(type);
      });
    } else {
      // Try to create a new audio element
      const newAudio = new Audio(SOUND_FILES[type]);
      newAudio.play().catch(err => {
        console.warn('Error playing sound file, using fallback:', err);
        playFallbackSound(type);
      });
    }
  } catch (error) {
    console.error(`Failed to play sound: ${type}`, error);
    playFallbackSound(type);
  }
};

/**
 * Play a fallback sound using Web Audio API
 * @param type The type of sound to play
 */
const playFallbackSound = (type: SoundType): void => {
  if (!audioContext) return;
  
  try {
    const buffer = fallbackSounds[type];
    if (buffer) {
      const source = audioContext.createBufferSource();
      source.buffer = buffer;
      source.connect(audioContext.destination);
      source.start();
    } else {
      // Create a simple beep as last resort
      const oscillator = audioContext.createOscillator();
      const gainNode = audioContext.createGain();
      
      oscillator.connect(gainNode);
      gainNode.connect(audioContext.destination);
      
      // Set properties based on sound type
      switch (type) {
        case 'move':
          oscillator.frequency.value = 440; // A4
          gainNode.gain.value = 0.1;
          break;
        case 'capture':
          oscillator.frequency.value = 330; // E4
          gainNode.gain.value = 0.2;
          break;
        case 'check':
          oscillator.frequency.value = 587; // D5
          gainNode.gain.value = 0.3;
          break;
        case 'castle':
          oscillator.frequency.value = 261; // C4
          gainNode.gain.value = 0.2;
          break;
        case 'game-end':
          oscillator.frequency.value = 196; // G3
          gainNode.gain.value = 0.3;
          break;
        case 'promote':
          oscillator.frequency.value = 523; // C5
          gainNode.gain.value = 0.2;
          break;
      }
      
      // Start and stop the oscillator
      oscillator.start();
      oscillator.stop(audioContext.currentTime + 0.2);
    }
  } catch (error) {
    console.error('Failed to play fallback sound:', error);
  }
};

/**
 * Play a sound if sound is enabled
 * @param type The type of sound to play
 */
export const playSoundIfEnabled = (type: SoundType): void => {
  if (soundEnabled) {
    playSound(type);
  }
};

/**
 * Toggle sound on/off
 * @param enabled Whether sound should be enabled
 */
export const toggleSound = (enabled?: boolean): boolean => {
  if (enabled !== undefined) {
    soundEnabled = enabled;
  } else {
    soundEnabled = !soundEnabled;
  }
  return soundEnabled;
};

/**
 * Set sound enabled state
 * @param enabled Whether sound should be enabled
 */
export const setSoundEnabled = (enabled: boolean): void => {
  soundEnabled = enabled;
};

/**
 * Check if sound is enabled
 */
export const isSoundEnabled = (): boolean => {
  return soundEnabled;
};