SciFi-XZBT/js/audio.js

class AudioManager {
  constructor() {
    this.ctx = null;
    this.isInitialized = false;
    this.isPlaying = false;
    this.masterGain = null;
    this.compressor = null;
    this.analyser = null;

    this.currentVolume = 0.75;
    this.isMuted = false;

    // Sleep Timer
    this.timerId = null;
    this.timerRemainingSeconds = 0;
    this.onTimerTick = null;
    this.onTimerComplete = null;
  }

  init() {
    if (this.isInitialized) return;

    const AudioContextClass = window.AudioContext || window.webkitAudioContext;
    this.ctx = new AudioContextClass();

    // Master Dynamics Compressor / Limiter for studio-quality mastering & anti-clipping
    this.compressor = this.ctx.createDynamicsCompressor();
    this.compressor.threshold.setValueAtTime(-12, this.ctx.currentTime);
    this.compressor.knee.setValueAtTime(8, this.ctx.currentTime);
    this.compressor.ratio.setValueAtTime(4, this.ctx.currentTime);
    this.compressor.attack.setValueAtTime(0.003, this.ctx.currentTime);
    this.compressor.release.setValueAtTime(0.25, this.ctx.currentTime);

    // Master Gain
    this.masterGain = this.ctx.createGain();
    this.masterGain.gain.setValueAtTime(this.isMuted ? 0 : this.currentVolume, this.ctx.currentTime);

    // Master Analyser Node for Visualizers
    this.analyser = this.ctx.createAnalyser();
    this.analyser.fftSize = 512;
    this.analyser.smoothingTimeConstant = 0.82;

    // Route: Nodes -> Compressor -> MasterGain -> Analyser -> Destination
    this.compressor.connect(this.masterGain);
    this.masterGain.connect(this.analyser);
    this.analyser.connect(this.ctx.destination);

    this.isInitialized = true;
  }

  async resume() {
    if (!this.isInitialized) this.init();
    if (this.ctx.state === 'suspended') {
      await this.ctx.resume();
    }
  }

  setMasterVolume(val, smoothTime = 0.05) {
    const clamped = Math.max(0, Math.min(1, val));
    this.currentVolume = clamped;
    if (this.masterGain && this.ctx) {
      const target = this.isMuted ? 0 : clamped;
      const now = this.ctx.currentTime;
      this.masterGain.gain.cancelScheduledValues(now);
      this.masterGain.gain.linearRampToValueAtTime(target, now + smoothTime);
    }
  }

  getMasterVolume() {
    return this.currentVolume;
  }

  toggleMute() {
    return this.setMute(!this.isMuted);
  }

  setMute(muted) {
    this.isMuted = !!muted;
    if (this.masterGain && this.ctx) {
      const target = this.isMuted ? 0 : this.currentVolume;
      const now = this.ctx.currentTime;
      this.masterGain.gain.cancelScheduledValues(now);
      this.masterGain.gain.linearRampToValueAtTime(target, now + 0.05);
    }
    return this.isMuted;
  }

  // Noise Buffer Helper (White, Pink, Brown)
  createNoiseBuffer(type = 'pink', durationSeconds = 5) {
    if (!this.ctx) this.init();
    const sampleRate = this.ctx.sampleRate;
    const bufferSize = sampleRate * durationSeconds;
    const buffer = this.ctx.createBuffer(2, bufferSize, sampleRate);
    const left = buffer.getChannelData(0);
    const right = buffer.getChannelData(1);

    if (type === 'white') {
      for (let i = 0; i < bufferSize; i++) {
        left[i] = Math.random() * 2 - 1;
        right[i] = Math.random() * 2 - 1;
      }
    } else if (type === 'pink') {
      let b0L = 0, b1L = 0, b2L = 0, b3L = 0, b4L = 0, b5L = 0, b6L = 0;
      let b0R = 0, b1R = 0, b2R = 0, b3R = 0, b4R = 0, b5R = 0, b6R = 0;
      for (let i = 0; i < bufferSize; i++) {
        const whiteL = Math.random() * 2 - 1;
        b0L = 0.99886 * b0L + whiteL * 0.0555179;
        b1L = 0.99332 * b1L + whiteL * 0.0750759;
        b2L = 0.96900 * b2L + whiteL * 0.1538520;
        b3L = 0.86650 * b3L + whiteL * 0.3104856;
        b4L = 0.55000 * b4L + whiteL * 0.5329522;
        b5L = -0.7616 * b5L - whiteL * 0.0168980;
        left[i] = (b0L + b1L + b2L + b3L + b4L + b5L + b6L + whiteL * 0.5362) * 0.11;
        b6L = whiteL * 0.115926;

        const whiteR = Math.random() * 2 - 1;
        b0R = 0.99886 * b0R + whiteR * 0.0555179;
        b1R = 0.99332 * b1R + whiteR * 0.0750759;
        b2R = 0.96900 * b2R + whiteR * 0.1538520;
        b3R = 0.86650 * b3R + whiteR * 0.3104856;
        b4R = 0.55000 * b4R + whiteR * 0.5329522;
        b5R = -0.7616 * b5R - whiteR * 0.0168980;
        right[i] = (b0R + b1R + b2R + b3R + b4R + b5R + b6R + whiteR * 0.5362) * 0.11;
        b6R = whiteR * 0.115926;
      }
    } else if (type === 'brown') {
      let lastOutL = 0.0;
      let lastOutR = 0.0;
      for (let i = 0; i < bufferSize; i++) {
        const whiteL = Math.random() * 2 - 1;
        lastOutL = (lastOutL + 0.02 * whiteL) / 1.02;
        left[i] = lastOutL * 3.5;

        const whiteR = Math.random() * 2 - 1;
        lastOutR = (lastOutR + 0.02 * whiteR) / 1.02;
        right[i] = lastOutR * 3.5;
      }
    }

    return buffer;
  }

  // Sleep Timer System
  startSleepTimer(minutes, onTick, onComplete) {
    this.stopSleepTimer();
    this.timerRemainingSeconds = Math.round(minutes * 60);
    this.onTimerTick = onTick;
    this.onTimerComplete = onComplete;

    if (this.onTimerTick) this.onTimerTick(this.timerRemainingSeconds);

    this.timerId = setInterval(() => {
      this.timerRemainingSeconds--;
      if (this.onTimerTick) this.onTimerTick(this.timerRemainingSeconds);

      // Begin exponential smooth fadeout during final 30 seconds
      if (this.timerRemainingSeconds <= 30 && this.timerRemainingSeconds > 0) {
        const factor = this.timerRemainingSeconds / 30;
        if (this.masterGain && this.ctx) {
          const targetVol = this.getMasterVolume() * factor;
          this.masterGain.gain.setValueAtTime(Math.max(0, targetVol), this.ctx.currentTime);
        }
      }

      if (this.timerRemainingSeconds <= 0) {
        this.stopSleepTimer();
        if (this.onTimerComplete) this.onTimerComplete();
      }
    }, 1000);
  }

  stopSleepTimer() {
    if (this.timerId) {
      clearInterval(this.timerId);
      this.timerId = null;
      this.timerRemainingSeconds = 0;
    }
  }
}

window.AudioManager = AudioManager;


/**
 * Hull Drone & Environmental Sub-Bass Synthesizer
 * Generates organic, continuous low-frequency starship structural vibration & room tone.
 */

class HullDroneSynth {
  constructor(audioManager) {
    this.am = audioManager;
    this.nodes = [];
    this.gainNode = null;
    this.filterNode = null;
    this.subOsc1 = null;
    this.subOsc2 = null;
    this.noiseSource = null;
    this.isMuted = false;

    // Default configuration parameters
    this.params = {
      volume: 0.7,
      baseFreq: 50,      // Fundamental frequency (e.g. 50Hz for TNG bridge)
      filterCutoff: 110,  // Lowpass filter cutoff
      resonance: 2.5,    // Filter Q / resonance peak
      noiseMix: 0.45,    // Brown noise texture mix
      harmonicSpread: 1.02 // Slight frequency detune between sub-oscillators for phasing
    };
  }

  start(rampDuration = 0) {
    this.stop();
    const ctx = this.am.ctx;
    if (!ctx) return;

    // Channel Gain Node
    this.gainNode = ctx.createGain();
    const targetVol = this.isMuted ? 0 : this.params.volume;
    if (rampDuration > 0) {
      this.gainNode.gain.setValueAtTime(0.0001, ctx.currentTime);
      this.gainNode.gain.linearRampToValueAtTime(targetVol, ctx.currentTime + rampDuration);
    } else {
      this.gainNode.gain.setValueAtTime(targetVol, ctx.currentTime);
    }

    // Steep Lowpass Filter (24dB/oct via 2 cascading biquads)
    this.filterNode = ctx.createBiquadFilter();
    this.filterNode.type = 'lowpass';
    this.filterNode.frequency.setValueAtTime(this.params.filterCutoff, ctx.currentTime);
    this.filterNode.Q.setValueAtTime(this.params.resonance, ctx.currentTime);

    const filterStage2 = ctx.createBiquadFilter();
    filterStage2.type = 'lowpass';
    filterStage2.frequency.setValueAtTime(this.params.filterCutoff * 1.5, ctx.currentTime);
    filterStage2.Q.setValueAtTime(1.0, ctx.currentTime);

    // Sub-bass Oscillator 1 (Sine)
    this.subOsc1 = ctx.createOscillator();
    this.subOsc1.type = 'sine';
    this.subOsc1.frequency.setValueAtTime(this.params.baseFreq, ctx.currentTime);

    const osc1Gain = ctx.createGain();
    osc1Gain.gain.setValueAtTime(0.5, ctx.currentTime);
    this.subOsc1.connect(osc1Gain);
    osc1Gain.connect(this.filterNode);

    // Sub-bass Oscillator 2 (Triangle/Sine detuned for slow, natural phase beating)
    this.subOsc2 = ctx.createOscillator();
    this.subOsc2.type = 'triangle';
    this.subOsc2.frequency.setValueAtTime(this.params.baseFreq * this.params.harmonicSpread, ctx.currentTime);

    const osc2Gain = ctx.createGain();
    osc2Gain.gain.setValueAtTime(0.3, ctx.currentTime);
    this.subOsc2.connect(osc2Gain);
    osc2Gain.connect(this.filterNode);

    // Brown Noise Structural Rumble Layer
    const brownBuffer = this.am.createNoiseBuffer('brown', 6);
    this.noiseSource = ctx.createBufferSource();
    this.noiseSource.buffer = brownBuffer;
    this.noiseSource.loop = true;

    const noiseGain = ctx.createGain();
    noiseGain.gain.setValueAtTime(this.params.noiseMix * 0.7, ctx.currentTime);
    this.noiseSource.connect(noiseGain);
    noiseGain.connect(this.filterNode);

    // Slow LFO for organic drifting movement
    const lfo = ctx.createOscillator();
    lfo.type = 'sine';
    lfo.frequency.setValueAtTime(0.1, ctx.currentTime); // 10 second cycle

    const lfoGain = ctx.createGain();
    lfoGain.gain.setValueAtTime(12, ctx.currentTime); // Modulate cutoff by ±12Hz
    lfo.connect(lfoGain);
    lfoGain.connect(this.filterNode.frequency);

    // Connect Graph
    this.filterNode.connect(filterStage2);
    filterStage2.connect(this.gainNode);
    this.gainNode.connect(this.am.compressor);

    // Start Sources
    this.subOsc1.start();
    this.subOsc2.start();
    this.noiseSource.start();
    lfo.start();

    this.nodes = [this.subOsc1, this.subOsc2, this.noiseSource, lfo, osc1Gain, osc2Gain, noiseGain, lfoGain, this.filterNode, filterStage2, this.gainNode];
  }

  stop(fadeDuration = 0) {
    if (fadeDuration > 0 && this.nodes.length > 0 && this.gainNode && this.am.ctx) {
      const now = this.am.ctx.currentTime;
      this.gainNode.gain.cancelScheduledValues(now);
      this.gainNode.gain.setValueAtTime(Math.max(0.0001, this.gainNode.gain.value), now);
      this.gainNode.gain.linearRampToValueAtTime(0.0001, now + fadeDuration);
      if (this.stoppingTimeout) clearTimeout(this.stoppingTimeout);
      this.stoppingTimeout = setTimeout(() => {
        this.stop(0);
      }, fadeDuration * 1000);
      return;
    }
    if (this.stoppingTimeout) {
      clearTimeout(this.stoppingTimeout);
      this.stoppingTimeout = null;
    }
    if (this.nodes.length > 0) {
      try {
        if (this.subOsc1) this.subOsc1.stop();
        if (this.subOsc2) this.subOsc2.stop();
        if (this.noiseSource) this.noiseSource.stop();
      } catch (e) {
        // Ignore if already stopped
      }
      this.nodes.forEach(node => {
        try { node.disconnect(); } catch (e) {}
      });
      this.nodes = [];
      this.subOsc1 = null;
      this.subOsc2 = null;
      this.noiseSource = null;
      this.gainNode = null;
    }
  }

  setVolume(val) {
    this.params.volume = Math.max(0, Math.min(1, val));
    if (this.gainNode && this.am.ctx && !this.isMuted) {
      const now = this.am.ctx.currentTime;
      this.gainNode.gain.cancelScheduledValues(now);
      this.gainNode.gain.linearRampToValueAtTime(this.params.volume, now + 0.05);
    }
  }

  setBaseFreq(freq) {
    this.params.baseFreq = freq;
    if (this.subOsc1 && this.subOsc2 && this.am.ctx) {
      const now = this.am.ctx.currentTime;
      this.subOsc1.frequency.linearRampToValueAtTime(freq, now + 0.1);
      this.subOsc2.frequency.linearRampToValueAtTime(freq * this.params.harmonicSpread, now + 0.1);
    }
  }

  setFilterCutoff(cutoff) {
    this.params.filterCutoff = cutoff;
    if (this.filterNode && this.am.ctx) {
      const now = this.am.ctx.currentTime;
      this.filterNode.frequency.linearRampToValueAtTime(cutoff, now + 0.1);
    }
  }

  applyPreset(config) {
    if (config.volume !== undefined) this.params.volume = config.volume;
    if (config.baseFreq !== undefined) this.setBaseFreq(config.baseFreq);
    if (config.filterCutoff !== undefined) this.setFilterCutoff(config.filterCutoff);
    if (config.resonance !== undefined) this.params.resonance = config.resonance;
    if (config.noiseMix !== undefined) this.params.noiseMix = config.noiseMix;
    if (config.harmonicSpread !== undefined) this.params.harmonicSpread = config.harmonicSpread;
    this.setVolume(this.params.volume);
  }
}

window.HullDroneSynth = HullDroneSynth;


/**
 * Warp Core & Reactor Pulse Synthesizer
 * Generates the iconic pulsating magnetic intermix thrum of Star Trek warp cores.
 */

class WarpCoreSynth {
  constructor(audioManager) {
    this.am = audioManager;
    this.nodes = [];
    this.gainNode = null;
    this.isMuted = false;

    // Pulse parameters
    this.params = {
      volume: 0.8,
      bpm: 48,             // Pulse rate (TNG is ~46-52 BPM, Voyager is ~68-75 BPM)
      carrierFreq: 58,     // Fundamental carrier pitch (Hz)
      modFreqRatio: 2.0,   // FM modulation frequency multiplier
      modIndex: 40,        // FM modulation depth
      filterCutoff: 180,   // Lowpass filter cutoff
      pulseShape: 'tng',   // 'tng', 'voyager', 'tos', 'defiant', 'nx'
      resonance: 3.0,
      swirlMix: 0.35       // Stereo phase swirl
    };

    this.pulseInterval = null;
    this.pulsePhase = 0;
    this.onPulse = null; // Callback for UI visualizer pulse animation!
  }

  start(rampDuration = 0) {
    this.stop();
    const ctx = this.am.ctx;
    if (!ctx) return;

    this.gainNode = ctx.createGain();
    const targetVol = this.isMuted ? 0 : this.params.volume;
    if (rampDuration > 0) {
      this.gainNode.gain.setValueAtTime(0.0001, ctx.currentTime);
      this.gainNode.gain.linearRampToValueAtTime(targetVol, ctx.currentTime + rampDuration);
    } else {
      this.gainNode.gain.setValueAtTime(targetVol, ctx.currentTime);
    }

    // Filter Node
    this.filterNode = ctx.createBiquadFilter();
    this.filterNode.type = 'lowpass';
    this.filterNode.frequency.setValueAtTime(this.params.filterCutoff, ctx.currentTime);
    this.filterNode.Q.setValueAtTime(this.params.resonance, ctx.currentTime);

    // Stereo Panner for magnetic swirl
    this.panner = ctx.createStereoPanner ? ctx.createStereoPanner() : null;

    // Carrier & Modulator Oscillators (FM Engine)
    this.carrier = ctx.createOscillator();
    this.carrier.type = this.params.pulseShape === 'tos' ? 'sawtooth' : (this.params.pulseShape === 'nx' ? 'triangle' : 'sine');
    if (rampDuration > 0) {
      this.carrier.frequency.setValueAtTime(Math.max(20, this.params.carrierFreq * 0.45), ctx.currentTime);
      this.carrier.frequency.exponentialRampToValueAtTime(this.params.carrierFreq, ctx.currentTime + rampDuration);
    } else {
      this.carrier.frequency.setValueAtTime(this.params.carrierFreq, ctx.currentTime);
    }

    // Sub-harmonic oscillator for massive bottom end
    this.subOsc = ctx.createOscillator();
    this.subOsc.type = 'sine';
    if (rampDuration > 0) {
      this.subOsc.frequency.setValueAtTime(Math.max(12, this.params.carrierFreq * 0.22), ctx.currentTime);
      this.subOsc.frequency.exponentialRampToValueAtTime(this.params.carrierFreq * 0.5, ctx.currentTime + rampDuration);
    } else {
      this.subOsc.frequency.setValueAtTime(this.params.carrierFreq * 0.5, ctx.currentTime);
    }

    const subGain = ctx.createGain();
    subGain.gain.setValueAtTime(0.6, ctx.currentTime);
    this.subOsc.connect(subGain);
    subGain.connect(this.filterNode);

    // Pulse Envelope Modulator Gain Node
    this.pulseGain = ctx.createGain();
    this.pulseGain.gain.setValueAtTime(0.2, ctx.currentTime);

    // Connect Carrier -> PulseGain -> Filter -> Panner -> ChannelGain -> Master
    this.carrier.connect(this.pulseGain);
    this.pulseGain.connect(this.filterNode);

    if (this.panner) {
      this.filterNode.connect(this.panner);
      this.panner.connect(this.gainNode);
    } else {
      this.filterNode.connect(this.gainNode);
    }

    this.gainNode.connect(this.am.compressor);

    this.carrier.start();
    this.subOsc.start();

    this.nodes = [this.carrier, this.subOsc, subGain, this.pulseGain, this.filterNode, this.gainNode];
    if (this.panner) this.nodes.push(this.panner);

    // Start precision pulse scheduler
    this.startPulseLoop();
  }

  startPulseLoop() {
    if (this.pulseInterval) clearInterval(this.pulseInterval);

    const intervalMs = (60 / this.params.bpm) * 1000;
    this.scheduleNextPulse();

    this.pulseInterval = setInterval(() => {
      this.scheduleNextPulse();
    }, intervalMs);
  }

  scheduleNextPulse() {
    const ctx = this.am.ctx;
    if (!ctx || !this.pulseGain || !this.filterNode) return;

    const now = ctx.currentTime;
    const pulseDuration = (60 / this.params.bpm);

    this.pulsePhase = (this.pulsePhase + 1) % 4;

    // Trigger visualizer callback
    if (this.onPulse) {
      this.onPulse(this.pulsePhase, pulseDuration);
    }

    // Dynamic envelope shaping based on ship era
    if (this.params.pulseShape === 'tng') {
      // Iconic 4-stage Galaxy-class magnetic warp pulse
      // Soft attack, deep swelling peak, secondary reverberant harmonic bloom, smooth decay
      const peakTime = now + pulseDuration * 0.28;
      const secondPeak = now + pulseDuration * 0.58;

      this.pulseGain.gain.cancelScheduledValues(now);
      this.pulseGain.gain.setValueAtTime(0.18, now);
      this.pulseGain.gain.linearRampToValueAtTime(0.95, peakTime);
      this.pulseGain.gain.exponentialRampToValueAtTime(0.45, now + pulseDuration * 0.42);
      this.pulseGain.gain.linearRampToValueAtTime(0.65, secondPeak);
      this.pulseGain.gain.exponentialRampToValueAtTime(0.18, now + pulseDuration * 0.95);

      // Modulate filter cutoff in sync with the pulse
      this.filterNode.frequency.cancelScheduledValues(now);
      this.filterNode.frequency.setValueAtTime(this.params.filterCutoff * 0.7, now);
      this.filterNode.frequency.exponentialRampToValueAtTime(this.params.filterCutoff * 1.6, peakTime);
      this.filterNode.frequency.exponentialRampToValueAtTime(this.params.filterCutoff * 0.7, now + pulseDuration * 0.95);

    } else if (this.params.pulseShape === 'voyager') {
      // Faster, sharper, higher-resonance Class 9 warp core
      const peakTime = now + pulseDuration * 0.2;
      this.pulseGain.gain.cancelScheduledValues(now);
      this.pulseGain.gain.setValueAtTime(0.25, now);
      this.pulseGain.gain.linearRampToValueAtTime(1.0, peakTime);
      this.pulseGain.gain.exponentialRampToValueAtTime(0.25, now + pulseDuration * 0.85);

      this.filterNode.frequency.cancelScheduledValues(now);
      this.filterNode.frequency.linearRampToValueAtTime(this.params.filterCutoff * 1.8, peakTime);
      this.filterNode.frequency.linearRampToValueAtTime(this.params.filterCutoff * 0.8, now + pulseDuration * 0.85);

    } else if (this.params.pulseShape === 'tos') {
      // TOS Electromechanical oscillating engine thrum
      const halfTime = now + pulseDuration * 0.5;
      this.pulseGain.gain.cancelScheduledValues(now);
      this.pulseGain.gain.setValueAtTime(0.4, now);
      this.pulseGain.gain.linearRampToValueAtTime(0.9, halfTime);
      this.pulseGain.gain.linearRampToValueAtTime(0.4, now + pulseDuration);

    } else if (this.params.pulseShape === 'defiant') {
      // Defiant: tight, aggressive pulse with rapid decay
      const peakTime = now + pulseDuration * 0.15;
      this.pulseGain.gain.cancelScheduledValues(now);
      this.pulseGain.gain.setValueAtTime(0.3, now);
      this.pulseGain.gain.linearRampToValueAtTime(1.0, peakTime);
      this.pulseGain.gain.exponentialRampToValueAtTime(0.3, now + pulseDuration * 0.75);

    } else {
      // NX / Industrial reactor chug
      const peakTime = now + pulseDuration * 0.35;
      this.pulseGain.gain.cancelScheduledValues(now);
      this.pulseGain.gain.setValueAtTime(0.2, now);
      this.pulseGain.gain.linearRampToValueAtTime(0.85, peakTime);
      this.pulseGain.gain.linearRampToValueAtTime(0.2, now + pulseDuration);
    }

    // Subtle stereo panning drift
    if (this.panner && this.params.swirlMix > 0) {
      const panTarget = Math.sin(this.pulsePhase * Math.PI * 0.5) * this.params.swirlMix;
      this.panner.pan.linearRampToValueAtTime(panTarget, now + pulseDuration * 0.5);
    }
  }

  setBpm(bpm) {
    this.params.bpm = Math.max(20, Math.min(160, bpm));
    if (this.nodes.length > 0) {
      this.startPulseLoop();
    }
  }

  setVolume(val) {
    this.params.volume = Math.max(0, Math.min(1, val));
    if (this.gainNode && this.am.ctx && !this.isMuted) {
      const now = this.am.ctx.currentTime;
      this.gainNode.gain.cancelScheduledValues(now);
      this.gainNode.gain.linearRampToValueAtTime(this.params.volume, now + 0.05);
    }
  }

  setCarrierFreq(freq) {
    this.params.carrierFreq = freq;
    if (this.carrier && this.subOsc && this.am.ctx) {
      const now = this.am.ctx.currentTime;
      this.carrier.frequency.linearRampToValueAtTime(freq, now + 0.1);
      this.subOsc.frequency.linearRampToValueAtTime(freq * 0.5, now + 0.1);
    }
  }

  stop(fadeDuration = 0) {
    if (fadeDuration > 0 && this.nodes.length > 0 && this.gainNode && this.am.ctx) {
      const now = this.am.ctx.currentTime;
      this.gainNode.gain.cancelScheduledValues(now);
      this.gainNode.gain.setValueAtTime(Math.max(0.0001, this.gainNode.gain.value), now);
      this.gainNode.gain.linearRampToValueAtTime(0.0001, now + fadeDuration);
      if (this.carrier) {
        try {
          this.carrier.frequency.cancelScheduledValues(now);
          this.carrier.frequency.setValueAtTime(this.carrier.frequency.value, now);
          this.carrier.frequency.linearRampToValueAtTime(Math.max(20, this.params.carrierFreq * 0.35), now + fadeDuration);
        } catch (e) {}
      }
      if (this.stoppingTimeout) clearTimeout(this.stoppingTimeout);
      this.stoppingTimeout = setTimeout(() => {
        this.stop(0);
      }, fadeDuration * 1000);
      return;
    }
    if (this.stoppingTimeout) {
      clearTimeout(this.stoppingTimeout);
      this.stoppingTimeout = null;
    }
    if (this.pulseInterval) {
      clearInterval(this.pulseInterval);
      this.pulseInterval = null;
    }
    if (this.nodes.length > 0) {
      try {
        if (this.carrier) this.carrier.stop();
        if (this.subOsc) this.subOsc.stop();
      } catch (e) {}
      this.nodes.forEach(node => {
        try { node.disconnect(); } catch (e) {}
      });
      this.nodes = [];
      this.carrier = null;
      this.subOsc = null;
      this.gainNode = null;
    }
  }

  applyPreset(config) {
    if (config.volume !== undefined) this.params.volume = config.volume;
    if (config.bpm !== undefined) this.setBpm(config.bpm);
    if (config.carrierFreq !== undefined) this.setCarrierFreq(config.carrierFreq);
    if (config.filterCutoff !== undefined) this.params.filterCutoff = config.filterCutoff;
    if (config.pulseShape !== undefined) this.params.pulseShape = config.pulseShape;
    if (config.resonance !== undefined) this.params.resonance = config.resonance;
    if (config.swirlMix !== undefined) this.params.swirlMix = config.swirlMix;
    this.setVolume(this.params.volume);
  }
}

window.WarpCoreSynth = WarpCoreSynth;


/**
 * Environmental Life Support & Airflow Synthesizer
 * Generates continuous ventilation airflow, atmospheric hiss, and room acoustic damping.
 */

class LifeSupportSynth {
  constructor(audioManager) {
    this.am = audioManager;
    this.nodes = [];
    this.gainNode = null;
    this.isMuted = false;

    this.params = {
      volume: 0.5,
      noiseType: 'pink',     // 'pink' (warm TNG), 'white' (crisp Voyager), 'brown' (heavy NX-01)
      highpassFreq: 180,     // Cuts extreme sub rumble to isolate air movement
      lowpassFreq: 1800,     // Gentle top-end rolloff
      airflowModSpeed: 0.15, // Subtle breathing movement of the environmental airflow
      airflowModDepth: 0.12  // Depth of airflow intensity modulation
    };
  }

  start(rampDuration = 0) {
    this.stop();
    const ctx = this.am.ctx;
    if (!ctx) return;

    this.gainNode = ctx.createGain();
    const targetVol = this.isMuted ? 0 : this.params.volume;
    if (rampDuration > 0) {
      this.gainNode.gain.setValueAtTime(0.0001, ctx.currentTime);
      this.gainNode.gain.linearRampToValueAtTime(targetVol, ctx.currentTime + rampDuration);
    } else {
      this.gainNode.gain.setValueAtTime(targetVol, ctx.currentTime);
    }

    // Highpass filter (cuts muddy lows)
    const hpFilter = ctx.createBiquadFilter();
    hpFilter.type = 'highpass';
    hpFilter.frequency.setValueAtTime(this.params.highpassFreq, ctx.currentTime);

    // Lowpass filter (shapes the crispness vs warmth of the air)
    this.lpFilter = ctx.createBiquadFilter();
    this.lpFilter.type = 'lowpass';
    this.lpFilter.frequency.setValueAtTime(this.params.lowpassFreq, ctx.currentTime);
    this.lpFilter.Q.setValueAtTime(0.7, ctx.currentTime);

    // Noise buffer source
    const noiseBuffer = this.am.createNoiseBuffer(this.params.noiseType, 6);
    this.noiseSource = ctx.createBufferSource();
    this.noiseSource.buffer = noiseBuffer;
    this.noiseSource.loop = true;

    // Slow airflow modulation LFO for organic breath
    const airflowLfo = ctx.createOscillator();
    airflowLfo.type = 'sine';
    airflowLfo.frequency.setValueAtTime(this.params.airflowModSpeed, ctx.currentTime);

    const lfoGain = ctx.createGain();
    lfoGain.gain.setValueAtTime(this.params.airflowModDepth, ctx.currentTime);

    const modGain = ctx.createGain();
    modGain.gain.setValueAtTime(0.8, ctx.currentTime);

    airflowLfo.connect(lfoGain);
    lfoGain.connect(modGain.gain);

    // Stereo widener using delay
    const splitter = ctx.createChannelSplitter(2);
    const merger = ctx.createChannelMerger(2);
    const delayRight = ctx.createDelay();
    delayRight.delayTime.setValueAtTime(0.018, ctx.currentTime); // 18ms Haas effect widening

    // Graph: Noise -> ModGain -> HP -> LP -> Splitter -> (Left direct, Right delay) -> Merger -> Gain -> Compressor
    this.noiseSource.connect(modGain);
    modGain.connect(hpFilter);
    hpFilter.connect(this.lpFilter);
    this.lpFilter.connect(splitter);

    splitter.connect(merger, 0, 0); // Left channel
    splitter.connect(delayRight, 1);
    delayRight.connect(merger, 0, 1); // Right delayed channel

    merger.connect(this.gainNode);
    this.gainNode.connect(this.am.compressor);

    this.noiseSource.start();
    airflowLfo.start();

    this.nodes = [
      this.noiseSource, airflowLfo, lfoGain, modGain,
      hpFilter, this.lpFilter, splitter, delayRight, merger, this.gainNode
    ];
  }

  stop(fadeDuration = 0) {
    if (fadeDuration > 0 && this.nodes.length > 0 && this.gainNode && this.am.ctx) {
      const now = this.am.ctx.currentTime;
      this.gainNode.gain.cancelScheduledValues(now);
      this.gainNode.gain.setValueAtTime(Math.max(0.0001, this.gainNode.gain.value), now);
      this.gainNode.gain.linearRampToValueAtTime(0.0001, now + fadeDuration);
      if (this.stoppingTimeout) clearTimeout(this.stoppingTimeout);
      this.stoppingTimeout = setTimeout(() => {
        this.stop(0);
      }, fadeDuration * 1000);
      return;
    }
    if (this.stoppingTimeout) {
      clearTimeout(this.stoppingTimeout);
      this.stoppingTimeout = null;
    }
    if (this.nodes.length > 0) {
      try {
        if (this.noiseSource) this.noiseSource.stop();
      } catch (e) {}
      this.nodes.forEach(node => {
        try { node.disconnect(); } catch (e) {}
      });
      this.nodes = [];
      this.noiseSource = null;
      this.gainNode = null;
    }
  }

  setVolume(val) {
    this.params.volume = Math.max(0, Math.min(1, val));
    if (this.gainNode && this.am.ctx && !this.isMuted) {
      const now = this.am.ctx.currentTime;
      this.gainNode.gain.cancelScheduledValues(now);
      this.gainNode.gain.linearRampToValueAtTime(this.params.volume, now + 0.05);
    }
  }

  setFilterCutoff(freq) {
    this.params.lowpassFreq = freq;
    if (this.lpFilter && this.am.ctx) {
      const now = this.am.ctx.currentTime;
      this.lpFilter.frequency.linearRampToValueAtTime(freq, now + 0.1);
    }
  }

  applyPreset(config) {
    if (config.volume !== undefined) this.params.volume = config.volume;
    if (config.noiseType !== undefined) this.params.noiseType = config.noiseType;
    if (config.highpassFreq !== undefined) this.params.highpassFreq = config.highpassFreq;
    if (config.lowpassFreq !== undefined) this.setFilterCutoff(config.lowpassFreq);
    if (config.airflowModSpeed !== undefined) this.params.airflowModSpeed = config.airflowModSpeed;
    if (config.airflowModDepth !== undefined) this.params.airflowModDepth = config.airflowModDepth;
    this.setVolume(this.params.volume);
  }
}

window.LifeSupportSynth = LifeSupportSynth;


/**
 * Procedural Starship Telemetry, LCARS Chirps, Beeps & Console Synthesizer
 * 100% synthesized programmatically via Web Audio API oscillators, FM synthesis, and envelopes.
 * Zero stored audio samples.
 */

class TelemetrySynth {
  constructor(audioManager) {
    this.am = audioManager;
    this.gainNode = null;
    this.isMuted = false;
    this.schedulerTimer = null;

    this.params = {
      volume: 0.4,
      density: 0.5,        // How often background telemetry chirps occur (0 = off, 1 = busy bridge)
      era: 'tng',          // 'tng', 'voyager', 'tos', 'ds9', 'nx'
      reverbMix: 0.25
    };

    // Musical pitch frequencies for authentic LCARS musical intervals (major/minor pentatonic & perfect 4ths/5ths)
    this.lcarsPitches = [
      880, 987.77, 1046.50, 1174.66, 1318.51, 1396.91, 1567.98, 1760, 1975.53, 2093.00, 2349.32, 2637.02
    ];

    // TOS Bridge oscillator warble frequencies
    this.tosFrequencies = [
      440, 554.37, 659.25, 830.61, 880, 1108.73, 1318.51, 1661.22, 2217.46
    ];
  }

  start() {
    this.stop();
    const ctx = this.am.ctx;
    if (!ctx) return;

    this.gainNode = ctx.createGain();
    this.gainNode.gain.setValueAtTime(this.isMuted ? 0 : this.params.volume, ctx.currentTime);
    this.gainNode.connect(this.am.compressor);

    this.startAutoTelemetryScheduler();
  }

  stop() {
    if (this.schedulerTimer) {
      clearTimeout(this.schedulerTimer);
      this.schedulerTimer = null;
    }
  }

  setVolume(val) {
    this.params.volume = Math.max(0, Math.min(1, val));
    if (this.gainNode && this.am.ctx && !this.isMuted) {
      const now = this.am.ctx.currentTime;
      this.gainNode.gain.cancelScheduledValues(now);
      this.gainNode.gain.linearRampToValueAtTime(this.params.volume, now + 0.05);
    }
  }

  setDensity(val) {
    this.params.density = Math.max(0, Math.min(1, val));
  }

  startAutoTelemetryScheduler() {
    if (this.schedulerTimer) clearTimeout(this.schedulerTimer);
    if (this.params.density <= 0.01) return;

    // Calculate delay inversely proportional to density (2s to 12s)
    const baseDelay = 12000 * (1.05 - this.params.density);
    const jitter = Math.random() * 4000;
    const nextInterval = Math.max(800, baseDelay + jitter);

    this.schedulerTimer = setTimeout(() => {
      this.playRandomTelemetrySound();
      this.startAutoTelemetryScheduler();
    }, nextInterval);
  }

  playRandomTelemetrySound() {
    if (this.isMuted || this.params.volume <= 0.01 || !this.am.ctx) return;

    switch (this.params.era) {
      case 'tos':
        Math.random() > 0.4 ? this.synthesizeTOSWarble() : this.synthesizeTOSRelayClick();
        break;
      case 'ds9':
        Math.random() > 0.5 ? this.synthesizeCardassianSensor() : this.synthesizeLCARSSingleChirp();
        break;
      case 'voyager': {
        const r = Math.random();
        if (r < 0.12) this.synthesizeCommBadge();
        else if (r < 0.55) this.synthesizeLCARSDoubleChirp();
        else this.synthesizeSensorSweep();
        break;
      }
      case 'nx':
        Math.random() > 0.5 ? this.synthesizeNXRelay() : this.synthesizeNXIndicatorBeep();
        break;
      case 'tng':
      default: {
        const r = Math.random();
        if (r < 0.10) this.synthesizeCommBadge();
        else if (r < 0.45) this.synthesizeLCARSSingleChirp();
        else if (r < 0.72) this.synthesizeLCARSDoubleChirp();
        else if (r < 0.88) this.synthesizeLCARSSequence();
        else this.synthesizeSensorSweep();
        break;
      }
    }

    // OBSERVATION intentionally treats telemetry as an abstract activity pulse,
    // not as a claim that a specific fictional beep means a specific thing.
    window.dispatchEvent(new CustomEvent('scifi-telemetry-activity', {
      detail: {
        era: this.params.era,
        density: this.params.density,
        firedAt: performance.now()
      }
    }));
  }

  /**
   * Star Trek Comm Badge Confirmation Chirp
   */
  synthesizeCommBadge() {
    if (window.expandedAudio) {
      window.expandedAudio.synthesizeCommBadge();
      return;
    }
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;
    const now = ctx.currentTime;
    [784, 1396.91].forEach((freq, idx) => {
      const t = now + idx * 0.038;
      const osc = ctx.createOscillator();
      osc.type = 'sine';
      osc.frequency.setValueAtTime(freq, t);
      const env = ctx.createGain();
      env.gain.setValueAtTime(0.001, t);
      env.gain.linearRampToValueAtTime(0.35, t + 0.005);
      env.gain.exponentialRampToValueAtTime(0.001, t + (idx === 0 ? 0.045 : 0.09));
      osc.connect(env);
      env.connect(this.gainNode);
      osc.start(t);
      osc.stop(t + (idx === 0 ? 0.05 : 0.095));
    });
  }

  /**
   * TNG/Voyager Single LCARS Touch Tone (Soft sine with gentle attack and rapid exponential decay)
   */
  synthesizeLCARSSingleChirp(pitch = null) {
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const freq = pitch || this.lcarsPitches[Math.floor(Math.random() * this.lcarsPitches.length)];
    const duration = 0.09;

    const osc = ctx.createOscillator();
    osc.type = 'sine';
    osc.frequency.setValueAtTime(freq, now);
    // Subtle downward micro-pitch glide (12Hz) for that warm capacitive touch feel
    osc.frequency.exponentialRampToValueAtTime(freq * 0.98, now + duration);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.35, now + 0.008);
    env.gain.exponentialRampToValueAtTime(0.0001, now + duration);

    // Filter to eliminate any click
    const filter = ctx.createBiquadFilter();
    filter.type = 'lowpass';
    filter.frequency.setValueAtTime(3200, now);

    osc.connect(env);
    env.connect(filter);
    filter.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration);
  }

  /**
   * TNG LCARS Double Chirp (Iconic standard confirmation tone)
   */
  synthesizeLCARSDoubleChirp() {
    const ctx = this.am.ctx;
    if (!ctx) return;
    const idx = Math.floor(Math.random() * (this.lcarsPitches.length - 2));
    const p1 = this.lcarsPitches[idx];
    const p2 = this.lcarsPitches[idx + 2]; // Minor third or fourth higher

    this.synthesizeLCARSSingleChirp(p1);
    setTimeout(() => {
      this.synthesizeLCARSSingleChirp(p2);
    }, 65);
  }

  /**
   * TNG LCARS Multi-Tone Data Acknowledgment Sequence
   */
  synthesizeLCARSSequence() {
    const ctx = this.am.ctx;
    if (!ctx) return;
    const notes = [
      this.lcarsPitches[Math.floor(Math.random() * 4) + 4],
      this.lcarsPitches[Math.floor(Math.random() * 4) + 6],
      this.lcarsPitches[Math.floor(Math.random() * 4) + 2]
    ];

    notes.forEach((freq, i) => {
      setTimeout(() => {
        this.synthesizeLCARSSingleChirp(freq);
      }, i * 75);
    });
  }

  /**
   * High-tech Sensor Sweep Tone (Voyager/TNG Long-Range Sensor telemetry)
   */
  synthesizeSensorSweep() {
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.38;
    const startFreq = 1200 + Math.random() * 800;
    const endFreq = startFreq * (Math.random() > 0.5 ? 1.6 : 0.65);

    const osc = ctx.createOscillator();
    osc.type = 'sine';
    osc.frequency.setValueAtTime(startFreq, now);
    osc.frequency.exponentialRampToValueAtTime(endFreq, now + duration);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.18, now + 0.05);
    env.gain.exponentialRampToValueAtTime(0.0001, now + duration);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration);
  }

  /**
   * TOS Original Series Bridge Electronic Computer Warble
   * Two detuned square/triangle oscillators modulated by high-speed vibrato LFO
   */
  synthesizeTOSWarble() {
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.45;
    const baseFreq = this.tosFrequencies[Math.floor(Math.random() * this.tosFrequencies.length)];

    const osc1 = ctx.createOscillator();
    osc1.type = 'triangle';
    osc1.frequency.setValueAtTime(baseFreq, now);

    const osc2 = ctx.createOscillator();
    osc2.type = 'sawtooth';
    osc2.frequency.setValueAtTime(baseFreq * 1.5, now);

    // Fast Vibrato LFO
    const lfo = ctx.createOscillator();
    lfo.type = 'sine';
    lfo.frequency.setValueAtTime(14 + Math.random() * 8, now); // 14-22 Hz warble

    const lfoGain = ctx.createGain();
    lfoGain.gain.setValueAtTime(35, now);
    lfo.connect(lfoGain);
    lfoGain.connect(osc1.frequency);
    lfoGain.connect(osc2.frequency);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.22, now + 0.04);
    env.gain.setValueAtTime(0.22, now + duration * 0.7);
    env.gain.exponentialRampToValueAtTime(0.0001, now + duration);

    // Bandpass filter to create that vintage analog 1960s telephone/relay resonance
    const filter = ctx.createBiquadFilter();
    filter.type = 'bandpass';
    filter.frequency.setValueAtTime(baseFreq * 1.2, now);
    filter.Q.setValueAtTime(3.5, now);

    osc1.connect(env);
    osc2.connect(env);
    env.connect(filter);
    filter.connect(this.gainNode);

    osc1.start(now);
    osc2.start(now);
    lfo.start(now);

    osc1.stop(now + duration);
    osc2.stop(now + duration);
    lfo.stop(now + duration);
  }

  /**
   * TOS Mechanical Relay Solenoid Click
   */
  synthesizeTOSRelayClick() {
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.025;

    const osc = ctx.createOscillator();
    osc.type = 'square';
    osc.frequency.setValueAtTime(1400, now);
    osc.frequency.exponentialRampToValueAtTime(300, now + duration);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.3, now);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration);
  }

  /**
   * DS9 / Cardassian Cavernous Sensor Tone (Resonant metallic ring)
   */
  synthesizeCardassianSensor() {
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.55;
    const freq = 420 + Math.random() * 200;

    const osc1 = ctx.createOscillator();
    osc1.type = 'sine';
    osc1.frequency.setValueAtTime(freq, now);

    const osc2 = ctx.createOscillator();
    osc2.type = 'sine';
    osc2.frequency.setValueAtTime(freq * 1.414, now); // Tritone metallic dissonance

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.2, now + 0.015);
    env.gain.exponentialRampToValueAtTime(0.0001, now + duration);

    osc1.connect(env);
    osc2.connect(env);
    env.connect(this.gainNode);

    osc1.start(now);
    osc2.start(now);
    osc1.stop(now + duration);
    osc2.stop(now + duration);
  }

  /**
   * NX-01 Industrial Hydraulic Relay Click
   */
  synthesizeNXRelay() {
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.04;

    const osc = ctx.createOscillator();
    osc.type = 'triangle';
    osc.frequency.setValueAtTime(750, now);
    osc.frequency.exponentialRampToValueAtTime(120, now + duration);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.25, now);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration);
  }

  /**
   * NX-01 Indicator Beep (Early 22nd century industrial tone)
   */
  synthesizeNXIndicatorBeep() {
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.08;

    const osc = ctx.createOscillator();
    osc.type = 'sine';
    osc.frequency.setValueAtTime(950, now);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.2, now + 0.005);
    env.gain.setValueAtTime(0.2, now + duration * 0.8);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration);
  }

  /**
   * Iconic TNG 2-Tone Door Chime ("Come in")
   */
  synthesizeDoorChime() {
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const f1 = 880;     // A5
    const f2 = 1174.66; // D6 (Up a fourth)

    const osc1 = ctx.createOscillator();
    osc1.type = 'sine';
    osc1.frequency.setValueAtTime(f1, now);

    const env1 = ctx.createGain();
    env1.gain.setValueAtTime(0.001, now);
    env1.gain.linearRampToValueAtTime(0.35, now + 0.015);
    env1.gain.exponentialRampToValueAtTime(0.001, now + 0.45);

    osc1.connect(env1);
    env1.connect(this.gainNode);
    osc1.start(now);
    osc1.stop(now + 0.45);

    // Second tone starts at 0.16s
    const osc2 = ctx.createOscillator();
    osc2.type = 'sine';
    osc2.frequency.setValueAtTime(f2, now + 0.16);

    const env2 = ctx.createGain();
    env2.gain.setValueAtTime(0.001, now + 0.16);
    env2.gain.linearRampToValueAtTime(0.4, now + 0.175);
    env2.gain.exponentialRampToValueAtTime(0.001, now + 0.7);

    osc2.connect(env2);
    env2.connect(this.gainNode);
    osc2.start(now + 0.16);
    osc2.stop(now + 0.7);
  }

  applyPreset(config) {
    if (config.volume !== undefined) this.params.volume = config.volume;
    if (config.density !== undefined) this.setDensity(config.density);
    if (config.era !== undefined) this.params.era = config.era;
    this.setVolume(this.params.volume);
    this.startAutoTelemetryScheduler();
  }
}

window.TelemetrySynth = TelemetrySynth;


/**
 * Procedural Starship Alert & Event Synthesizer
 * 100% synthesized programmatically in Web Audio API.
 * Includes TNG Red Alert (3-tone), TOS Red Alert (hooter buzzer), Movie-era descending klaxon,
 * Yellow Alert chime, and dynamic Warp Drive Throttle swell.
 */

class AlertSynth {
  constructor(audioManager) {
    this.am = audioManager;
    this.gainNode = null;
    this.activeAlert = null; // 'red', 'yellow', null
    this.alertTimer = null;
    this.alertType = 'tng';  // 'tng', 'tos', 'movie'

    this.params = {
      volume: 0.6
    };
  }

  init() {
    if (this.gainNode || !this.am.ctx) return;
    const ctx = this.am.ctx;
    this.gainNode = ctx.createGain();
    this.gainNode.gain.setValueAtTime(this.params.volume, ctx.currentTime);
    this.gainNode.connect(this.am.compressor);
  }

  setVolume(val) {
    this.params.volume = Math.max(0, Math.min(1, val));
    if (this.gainNode && this.am.ctx) {
      const now = this.am.ctx.currentTime;
      this.gainNode.gain.linearRampToValueAtTime(this.params.volume, now + 0.05);
    }
  }

  triggerRedAlert(type = 'tng') {
    this.init();
    this.stopAlert();
    this.activeAlert = 'red';
    this.alertType = type;

    const playLoop = () => {
      if (this.activeAlert !== 'red') return;
      let loopDuration = 1.35;

      if (this.alertType === 'tng') {
        this.synthesizeTNGRedAlertCycle();
        loopDuration = 1.35;
      } else if (this.alertType === 'tos') {
        this.synthesizeTOSRedAlertCycle();
        loopDuration = 1.1;
      } else {
        this.synthesizeMovieRedAlertCycle();
        loopDuration = 1.4;
      }

      this.alertTimer = setTimeout(playLoop, loopDuration * 1000);
    };

    playLoop();
  }

  triggerYellowAlert() {
    this.init();
    this.stopAlert();
    this.activeAlert = 'yellow';

    const playLoop = () => {
      if (this.activeAlert !== 'yellow') return;
      this.synthesizeYellowAlertCycle();
      this.alertTimer = setTimeout(playLoop, 2200);
    };

    playLoop();
  }

  stopAlert() {
    this.activeAlert = null;
    if (this.alertTimer) {
      clearTimeout(this.alertTimer);
      this.alertTimer = null;
    }
  }

  /**
   * TNG Red Alert Klaxon (3-tone rising & cascading electronic horn with resonant envelope)
   */
  synthesizeTNGRedAlertCycle() {
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    // Frequencies for the iconic TNG 3-tone klaxon chord: F5 (698.46Hz), Ab5 (830.61Hz), C6 (1046.50Hz)
    const freqs = [698.46, 830.61, 1046.50];

    freqs.forEach((freq, idx) => {
      const osc = ctx.createOscillator();
      osc.type = 'sawtooth';
      osc.frequency.setValueAtTime(freq * 0.94, now);
      // Fast upward swoop on trigger
      osc.frequency.exponentialRampToValueAtTime(freq, now + 0.12);

      // Lowpass filter to give that brassy starship horn acoustic resonance
      const filter = ctx.createBiquadFilter();
      filter.type = 'lowpass';
      filter.frequency.setValueAtTime(1600, now);
      filter.Q.setValueAtTime(4.0, now);

      const env = ctx.createGain();
      env.gain.setValueAtTime(0.001, now);
      env.gain.linearRampToValueAtTime(0.25 / freqs.length, now + 0.08);
      env.gain.setValueAtTime(0.25 / freqs.length, now + 0.45);
      env.gain.exponentialRampToValueAtTime(0.0001, now + 0.85);

      osc.connect(filter);
      filter.connect(env);
      env.connect(this.gainNode);

      osc.start(now);
      osc.stop(now + 0.86);
    });
  }

  /**
   * TOS Red Alert Buzzer / Hooter Siren (Pulsing 2-tone frequency modulation)
   */
  synthesizeTOSRedAlertCycle() {
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.85;

    const osc = ctx.createOscillator();
    osc.type = 'sawtooth';
    osc.frequency.setValueAtTime(540, now);
    osc.frequency.linearRampToValueAtTime(920, now + duration * 0.5);
    osc.frequency.linearRampToValueAtTime(540, now + duration);

    const filter = ctx.createBiquadFilter();
    filter.type = 'bandpass';
    filter.frequency.setValueAtTime(800, now);
    filter.Q.setValueAtTime(2.2, now);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.01, now);
    env.gain.linearRampToValueAtTime(0.28, now + 0.05);
    env.gain.setValueAtTime(0.28, now + duration * 0.85);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    osc.connect(filter);
    filter.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration);
  }

  /**
   * Star Trek Movie Era Refit Descending Red Alert Klaxon
   */
  synthesizeMovieRedAlertCycle() {
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 1.05;

    const osc = ctx.createOscillator();
    osc.type = 'sawtooth';
    osc.frequency.setValueAtTime(1350, now);
    osc.frequency.exponentialRampToValueAtTime(420, now + duration * 0.9);

    const filter = ctx.createBiquadFilter();
    filter.type = 'lowpass';
    filter.frequency.setValueAtTime(2200, now);
    filter.Q.setValueAtTime(3.5, now);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.01, now);
    env.gain.linearRampToValueAtTime(0.3, now + 0.06);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    osc.connect(filter);
    filter.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration);
  }

  /**
   * Yellow Alert Pulsing Warning Chime
   */
  synthesizeYellowAlertCycle() {
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const f1 = 660; // E5
    const f2 = 880; // A5

    [0, 0.22].forEach((offset, idx) => {
      const freq = idx === 0 ? f1 : f2;
      const osc = ctx.createOscillator();
      osc.type = 'sine';
      osc.frequency.setValueAtTime(freq, now + offset);

      const env = ctx.createGain();
      env.gain.setValueAtTime(0.001, now + offset);
      env.gain.linearRampToValueAtTime(0.32, now + offset + 0.015);
      env.gain.exponentialRampToValueAtTime(0.001, now + offset + 0.5);

      osc.connect(env);
      env.connect(this.gainNode);

      osc.start(now + offset);
      osc.stop(now + offset + 0.52);
    });
  }

  /**
   * Procedural Warp Drive Acceleration Swell ("Engage!")
   * Synthesizes rising plasma induction whine + deep bass detonation
   */
  synthesizeWarpJump() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 2.8;

    // 1. Rising High Induction Whine
    const whineOsc = ctx.createOscillator();
    whineOsc.type = 'sawtooth';
    whineOsc.frequency.setValueAtTime(80, now);
    whineOsc.frequency.exponentialRampToValueAtTime(3800, now + 1.8);
    whineOsc.frequency.exponentialRampToValueAtTime(14000, now + 2.5);

    const whineFilter = ctx.createBiquadFilter();
    whineFilter.type = 'bandpass';
    whineFilter.frequency.setValueAtTime(200, now);
    whineFilter.frequency.exponentialRampToValueAtTime(4500, now + 1.8);
    whineFilter.Q.setValueAtTime(5.0, now);

    const whineEnv = ctx.createGain();
    whineEnv.gain.setValueAtTime(0.01, now);
    whineEnv.gain.linearRampToValueAtTime(0.35, now + 1.6);
    whineEnv.gain.exponentialRampToValueAtTime(0.001, now + 2.7);

    whineOsc.connect(whineFilter);
    whineFilter.connect(whineEnv);
    whineEnv.connect(this.gainNode);

    // 2. Sub-bass Matter-Antimatter Boom
    const subOsc = ctx.createOscillator();
    subOsc.type = 'sine';
    subOsc.frequency.setValueAtTime(140, now + 1.4);
    subOsc.frequency.exponentialRampToValueAtTime(32, now + 2.6);

    const subEnv = ctx.createGain();
    subEnv.gain.setValueAtTime(0.001, now + 1.4);
    subEnv.gain.linearRampToValueAtTime(0.7, now + 1.7);
    subEnv.gain.exponentialRampToValueAtTime(0.0001, now + duration);

    subOsc.connect(subEnv);
    subEnv.connect(this.gainNode);

    whineOsc.start(now);
    whineOsc.stop(now + 2.7);
    subOsc.start(now + 1.4);
    subOsc.stop(now + duration);
  }
}

window.AlertSynth = AlertSynth;


/**
 * Procedural Doctor Who & TARDIS Sound Synthesizer
 * 100% synthesized programmatically via Web Audio API.
 * Includes Dematerialization Wheeze-Groan, Cloister Bell, Sonic Screwdriver, and TARDIS Console Foley.
 */

class WhoniverseAudioSynth {
  constructor(audioManager) {
    this.am = audioManager;
    this.gainNode = null;
    this.activeCloister = false;
    this.cloisterTimer = null;
  }

  init() {
    if (this.gainNode || !this.am.ctx) return;
    const ctx = this.am.ctx;
    this.gainNode = ctx.createGain();
    this.gainNode.gain.setValueAtTime(0.7, ctx.currentTime);
    this.gainNode.connect(this.am.compressor);
  }

  /**
   * Procedural TARDIS Materialization / Dematerialization ("Wheeze-Groan")
   * Modeled after Brian Hodgson's 1963 BBC Radiophonic technique:
   * Dragging keys on piano bass strings -> reverse playback -> slow tape speed -> feedback loop.
   */
  synthesizeDematCycle(cycles = 4) {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx) return;

    for (let c = 0; c < cycles; c++) {
      const cycleStart = ctx.currentTime + c * 1.85;
      this.synthesizeSingleDematSwell(cycleStart, c, cycles);
    }
  }

  synthesizeSingleDematSwell(startTime, cycleIndex, totalCycles) {
    const ctx = this.am.ctx;
    const duration = 1.75;

    // Intensity fades slightly on later cycles
    const intensity = 1.0 - (cycleIndex / totalCycles) * 0.35;

    // 1. Friction Scrape Carrier (Sawtooth through resonant highpass/bandpass with frequency glide)
    const frictionOsc = ctx.createOscillator();
    frictionOsc.type = 'sawtooth';
    // Frequency glides up then groans down
    frictionOsc.frequency.setValueAtTime(120, startTime);
    frictionOsc.frequency.exponentialRampToValueAtTime(840, startTime + 0.65);
    frictionOsc.frequency.exponentialRampToValueAtTime(95, startTime + duration);

    // Filter modeling the piano soundboard metallic scraping resonance
    const frictionFilter = ctx.createBiquadFilter();
    frictionFilter.type = 'bandpass';
    frictionFilter.frequency.setValueAtTime(320, startTime);
    frictionFilter.frequency.exponentialRampToValueAtTime(1450, startTime + 0.65);
    frictionFilter.frequency.exponentialRampToValueAtTime(220, startTime + duration);
    frictionFilter.Q.setValueAtTime(4.5, startTime);

    const frictionGain = ctx.createGain();
    frictionGain.gain.setValueAtTime(0.001, startTime);
    frictionGain.gain.linearRampToValueAtTime(0.4 * intensity, startTime + 0.45);
    frictionGain.gain.exponentialRampToValueAtTime(0.001, startTime + duration);

    // 2. Sub-Vortex Resonant Groan (FM synthesis for the deep cosmic groaning undertone)
    const groanCarrier = ctx.createOscillator();
    groanCarrier.type = 'triangle';
    groanCarrier.frequency.setValueAtTime(55, startTime);
    groanCarrier.frequency.linearRampToValueAtTime(138, startTime + 0.55);
    groanCarrier.frequency.exponentialRampToValueAtTime(48, startTime + duration);

    const groanMod = ctx.createOscillator();
    groanMod.type = 'sine';
    groanMod.frequency.setValueAtTime(28, startTime); // Phasing FM modulator
    groanMod.frequency.linearRampToValueAtTime(65, startTime + 0.6);

    const groanModGain = ctx.createGain();
    groanModGain.gain.setValueAtTime(45, startTime);
    groanMod.connect(groanModGain);
    groanModGain.connect(groanCarrier.frequency);

    const groanGain = ctx.createGain();
    groanGain.gain.setValueAtTime(0.001, startTime);
    groanGain.gain.linearRampToValueAtTime(0.6 * intensity, startTime + 0.5);
    groanGain.gain.exponentialRampToValueAtTime(0.001, startTime + duration);

    // 3. Phasing Flutter / Swell (Tape-flange simulation via slow LFO)
    const lfo = ctx.createOscillator();
    lfo.type = 'sine';
    lfo.frequency.setValueAtTime(5.5, startTime); // 5.5 Hz flanging flutter

    const lfoDepth = ctx.createGain();
    lfoDepth.gain.setValueAtTime(0.25, startTime);
    lfo.connect(lfoDepth);
    lfoDepth.connect(frictionGain.gain);

    // Connect Graph
    frictionOsc.connect(frictionFilter);
    frictionFilter.connect(frictionGain);
    frictionGain.connect(this.gainNode);

    groanCarrier.connect(groanGain);
    groanGain.connect(this.gainNode);

    // Trigger Nodes
    frictionOsc.start(startTime);
    frictionOsc.stop(startTime + duration);
    groanCarrier.start(startTime);
    groanCarrier.stop(startTime + duration);
    groanMod.start(startTime);
    groanMod.stop(startTime + duration);
    lfo.start(startTime);
    lfo.stop(startTime + duration);
  }

  /**
   * Procedural Cloister Bell (Deep, ominous bronze cathedral bell)
   */
  triggerCloisterBell() {
    this.init();
    this.stopCloisterBell();
    this.activeCloister = true;

    const ringLoop = () => {
      if (!this.activeCloister) return;
      this.synthesizeCloisterStrike();
      this.cloisterTimer = setTimeout(ringLoop, 3200); // Canonical cloister bell repetition rate
    };

    ringLoop();
  }

  stopCloisterBell() {
    this.activeCloister = false;
    if (this.cloisterTimer) {
      clearTimeout(this.cloisterTimer);
      this.cloisterTimer = null;
    }
  }

  synthesizeCloisterStrike() {
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 4.2;

    // Authentic bell inharmonic partial ratios: Fundamental, Minor 3rd, 5th, Octave, Major 7th
    const bellPartials = [
      { freqRatio: 1.0,  gain: 0.65, decay: 4.2 }, // Fundamental ~108 Hz
      { freqRatio: 1.19, gain: 0.45, decay: 3.6 }, // Minor third
      { freqRatio: 1.51, gain: 0.40, decay: 3.1 }, // Fifth
      { freqRatio: 2.01, gain: 0.30, decay: 2.4 }, // Octave
      { freqRatio: 2.74, gain: 0.22, decay: 1.8 }, // Upper strike tone
      { freqRatio: 3.42, gain: 0.15, decay: 1.2 }  // High strike transient
    ];

    const basePitch = 108.0; // Deep bronze bell pitch

    bellPartials.forEach(p => {
      const osc = ctx.createOscillator();
      osc.type = 'sine';
      osc.frequency.setValueAtTime(basePitch * p.freqRatio, now);

      const env = ctx.createGain();
      env.gain.setValueAtTime(0.001, now);
      env.gain.linearRampToValueAtTime(p.gain * 0.35, now + 0.012); // Sharp hammer impact
      env.gain.exponentialRampToValueAtTime(0.0001, now + p.decay);

      osc.connect(env);
      env.connect(this.gainNode);

      osc.start(now);
      osc.stop(now + p.decay + 0.05);
    });
  }

  /**
   * Procedural Sonic Screwdriver (High-frequency modulated sweep & vibrato warble)
   */
  synthesizeSonicScrewdriver(durationSeconds = 1.2) {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = durationSeconds;

    // Dual square/saw oscillators
    const osc1 = ctx.createOscillator();
    osc1.type = 'square';
    osc1.frequency.setValueAtTime(2350, now);
    osc1.frequency.linearRampToValueAtTime(2650, now + duration * 0.5);
    osc1.frequency.linearRampToValueAtTime(2350, now + duration);

    const osc2 = ctx.createOscillator();
    osc2.type = 'sawtooth';
    osc2.frequency.setValueAtTime(2362, now); // 12Hz natural phase beat

    // Rapid Vibrato LFO
    const vibrato = ctx.createOscillator();
    vibrato.type = 'sine';
    vibrato.frequency.setValueAtTime(32, now); // 32 Hz warble rate

    const vibGain = ctx.createGain();
    vibGain.gain.setValueAtTime(140, now);
    vibrato.connect(vibGain);
    vibGain.connect(osc1.frequency);
    vibGain.connect(osc2.frequency);

    // Bandpass filter for metallic resonance
    const filter = ctx.createBiquadFilter();
    filter.type = 'bandpass';
    filter.frequency.setValueAtTime(2500, now);
    filter.Q.setValueAtTime(4.0, now);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.28, now + 0.03);
    env.gain.setValueAtTime(0.28, now + duration * 0.85);
    env.gain.exponentialRampToValueAtTime(0.0001, now + duration);

    osc1.connect(filter);
    osc2.connect(filter);
    filter.connect(env);
    env.connect(this.gainNode);

    osc1.start(now);
    osc2.start(now);
    vibrato.start(now);
    osc1.stop(now + duration);
    osc2.stop(now + duration);
    vibrato.stop(now + duration);
  }

  /**
   * Fast-Return Spring Lever (Heavy spring recoil clack + resonant ring)
   */
  synthesizeFastReturn() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.35;

    const osc = ctx.createOscillator();
    osc.type = 'triangle';
    osc.frequency.setValueAtTime(620, now);
    osc.frequency.exponentialRampToValueAtTime(95, now + 0.08);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.45, now);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration);
  }

  /**
   * TARDIS Demat Switch / Relay Solenoid
   */
  synthesizeDematSwitch() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.06;

    const osc = ctx.createOscillator();
    osc.type = 'square';
    osc.frequency.setValueAtTime(850, now);
    osc.frequency.exponentialRampToValueAtTime(140, now + duration);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.35, now);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration);
  }

  /**
   * Telepathic Circuit Chime (Glassy, mystical resonance)
   */
  synthesizeTelepathicChime() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 1.4;
    const notes = [1046.50, 1318.51, 1567.98, 2093.00]; // C Major arpeggio shimmer

    notes.forEach((freq, idx) => {
      const osc = ctx.createOscillator();
      osc.type = 'sine';
      osc.frequency.setValueAtTime(freq, now + idx * 0.08);

      const env = ctx.createGain();
      env.gain.setValueAtTime(0.001, now + idx * 0.08);
      env.gain.linearRampToValueAtTime(0.18, now + idx * 0.08 + 0.02);
      env.gain.exponentialRampToValueAtTime(0.0001, now + duration);

      osc.connect(env);
      env.connect(this.gainNode);

      osc.start(now + idx * 0.08);
      osc.stop(now + duration + 0.05);
    });
  }

  /**
   * TARDIS Lever-Throw Clunk (Tactile mechanical switch)
   * Hard square transient click coupled to a dull highpass noise thump
   */
  synthesizeLeverClunk() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;

    // Hard square transient click
    const clickOsc = ctx.createOscillator();
    clickOsc.type = 'square';
    clickOsc.frequency.setValueAtTime(80, now);
    clickOsc.frequency.exponentialRampToValueAtTime(30, now + 0.035);

    const clickEnv = ctx.createGain();
    clickEnv.gain.setValueAtTime(0.42, now);
    clickEnv.gain.exponentialRampToValueAtTime(0.001, now + 0.04);

    clickOsc.connect(clickEnv);
    clickEnv.connect(this.gainNode);
    clickOsc.start(now);
    clickOsc.stop(now + 0.042);

    // Dull highpass noise thump
    const noiseBuf = this.am.createNoiseBuffer('pink', 0.15);
    const noise = ctx.createBufferSource();
    noise.buffer = noiseBuf;

    const filter = ctx.createBiquadFilter();
    filter.type = 'highpass';
    filter.frequency.setValueAtTime(320, now);

    const noiseEnv = ctx.createGain();
    noiseEnv.gain.setValueAtTime(0.3, now);
    noiseEnv.gain.exponentialRampToValueAtTime(0.001, now + 0.06);

    noise.connect(filter);
    filter.connect(noiseEnv);
    noiseEnv.connect(this.gainNode);
    noise.start(now);
    noise.stop(now + 0.065);
  }

  /**
   * TARDIS Police Box Exterior Door Open / Close (Wood creak + mortise latch)
   * Modulated bandpass friction noise layered over a sharp metallic dual-click transient
   */
  synthesizeTardisDoor() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.75;

    // 1. Modulated bandpass friction noise (wood creak)
    const creakBuf = this.am.createNoiseBuffer('brown', duration);
    const creak = ctx.createBufferSource();
    creak.buffer = creakBuf;

    const creakFilter = ctx.createBiquadFilter();
    creakFilter.type = 'bandpass';
    creakFilter.frequency.setValueAtTime(260, now);
    creakFilter.frequency.linearRampToValueAtTime(540, now + 0.35);
    creakFilter.frequency.exponentialRampToValueAtTime(310, now + 0.65);
    creakFilter.Q.setValueAtTime(6.0, now);

    const creakEnv = ctx.createGain();
    creakEnv.gain.setValueAtTime(0.001, now);
    creakEnv.gain.linearRampToValueAtTime(0.38, now + 0.15);
    creakEnv.gain.exponentialRampToValueAtTime(0.001, now + 0.68);

    creak.connect(creakFilter);
    creakFilter.connect(creakEnv);
    creakEnv.connect(this.gainNode);
    creak.start(now);
    creak.stop(now + 0.7);

    // 2. Iron mortise latch dual-click transient
    [0.54, 0.62].forEach((offset, idx) => {
      const click = ctx.createOscillator();
      click.type = 'triangle';
      click.frequency.setValueAtTime(idx === 0 ? 1100 : 750, now + offset);
      click.frequency.exponentialRampToValueAtTime(180, now + offset + 0.03);

      const cEnv = ctx.createGain();
      cEnv.gain.setValueAtTime(0.28, now + offset);
      cEnv.gain.exponentialRampToValueAtTime(0.001, now + offset + 0.035);

      click.connect(cEnv);
      cEnv.connect(this.gainNode);
      click.start(now + offset);
      click.stop(now + offset + 0.04);
    });
  }
}

window.WhoniverseAudioSynth = WhoniverseAudioSynth;


/**
 * Procedural Audio Synthesizers for Expanded Sci-Fi Universes
 * Generates Epstein drives, Bio-ship neural pulses, DRADIS sonar, Singularity drives,
 * Retro analog tone glides, and Ludicrous speed reality shifts via Web Audio API.
 */

class ExpandedSciFiAudioSynth {
  constructor(audioManager) {
    this.am = audioManager;
    this.gainNode = null;
    this.medicalTimer = null;
    this.sparkTimer = null;
  }

  init() {
    if (this.gainNode || !this.am.ctx) return;
    const ctx = this.am.ctx;
    this.gainNode = ctx.createGain();
    this.gainNode.gain.setValueAtTime(0.7, ctx.currentTime);
    this.gainNode.connect(this.am.compressor);
  }

  /**
   * Epstein Drive Fusion Torch Burn (The Expanse / Industrial Space)
   * Tremendous raw fusion thrust with high-pressure magnetic plasma acceleration
   */
  synthesizeEpsteinBurn() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx) return;

    const now = ctx.currentTime;
    const duration = 3.5;

    // 1. High-frequency plasma induction whine
    const whineOsc = ctx.createOscillator();
    whineOsc.type = 'sawtooth';
    whineOsc.frequency.setValueAtTime(140, now);
    whineOsc.frequency.exponentialRampToValueAtTime(1800, now + 1.2);
    whineOsc.frequency.exponentialRampToValueAtTime(3200, now + 2.5);

    const whineFilter = ctx.createBiquadFilter();
    whineFilter.type = 'bandpass';
    whineFilter.frequency.setValueAtTime(280, now);
    whineFilter.frequency.exponentialRampToValueAtTime(2600, now + 2.0);
    whineFilter.Q.setValueAtTime(4.0, now);

    const whineGain = ctx.createGain();
    whineGain.gain.setValueAtTime(0.001, now);
    whineGain.gain.linearRampToValueAtTime(0.35, now + 1.0);
    whineGain.gain.exponentialRampToValueAtTime(0.001, now + duration);

    whineOsc.connect(whineFilter);
    whineFilter.connect(whineGain);
    whineGain.connect(this.gainNode);

    // 2. Colossal fusion blast roar (filtered noise)
    const roarBuffer = this.am.createNoiseBuffer('brown', 4);
    const roarSource = ctx.createBufferSource();
    roarSource.buffer = roarBuffer;

    const roarFilter = ctx.createBiquadFilter();
    roarFilter.type = 'lowpass';
    roarFilter.frequency.setValueAtTime(180, now);
    roarFilter.frequency.linearRampToValueAtTime(550, now + 1.2);
    roarFilter.frequency.exponentialRampToValueAtTime(120, now + duration);

    const roarGain = ctx.createGain();
    roarGain.gain.setValueAtTime(0.001, now);
    roarGain.gain.linearRampToValueAtTime(0.7, now + 1.2);
    roarGain.gain.exponentialRampToValueAtTime(0.001, now + duration);

    roarSource.connect(roarFilter);
    roarFilter.connect(roarGain);
    roarGain.connect(this.gainNode);

    whineOsc.start(now);
    whineOsc.stop(now + duration);
    roarSource.start(now);
    roarSource.stop(now + duration);
  }

  /**
   * Bio-Ship Starburst / Neural Pulse (Farscape Moya & Bioships)
   * Organic vocalized dimensional fold and vascular wave
   */
  synthesizeStarburst() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx) return;

    const now = ctx.currentTime;
    const duration = 2.8;

    const osc1 = ctx.createOscillator();
    osc1.type = 'sine';
    osc1.frequency.setValueAtTime(85, now);
    osc1.frequency.exponentialRampToValueAtTime(940, now + 1.4);
    osc1.frequency.exponentialRampToValueAtTime(45, now + duration);

    const osc2 = ctx.createOscillator();
    osc2.type = 'triangle';
    osc2.frequency.setValueAtTime(125, now);
    osc2.frequency.exponentialRampToValueAtTime(1420, now + 1.4);
    osc2.frequency.exponentialRampToValueAtTime(65, now + duration);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.45, now + 1.3);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    osc1.connect(env);
    osc2.connect(env);
    env.connect(this.gainNode);

    osc1.start(now);
    osc2.start(now);
    osc1.stop(now + duration);
    osc2.stop(now + duration);
  }

  /**
   * Battlestar Galactica DRADIS Sonar Ping (Military Space)
   * The iconic tactical combat contact echo
   */
  synthesizeDradisPing() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx) return;

    const now = ctx.currentTime;
    const duration = 1.4;

    const osc = ctx.createOscillator();
    osc.type = 'sine';
    osc.frequency.setValueAtTime(1860, now);
    osc.frequency.exponentialRampToValueAtTime(1540, now + 0.08);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.35, now + 0.01);
    env.gain.exponentialRampToValueAtTime(0.0001, now + duration);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration);
  }

  /**
   * FTL Jump Thunderclap (BSG / Military Space)
   * Sudden vacuum displacement shockwave
   */
  synthesizeFtlJump() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx) return;

    const now = ctx.currentTime;
    const duration = 2.2;

    const noiseBuffer = this.am.createNoiseBuffer('brown', 2.5);
    const noise = ctx.createBufferSource();
    noise.buffer = noiseBuffer;

    const filter = ctx.createBiquadFilter();
    filter.type = 'lowpass';
    filter.frequency.setValueAtTime(800, now);
    filter.frequency.exponentialRampToValueAtTime(45, now + 1.8);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.8, now);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    noise.connect(filter);
    filter.connect(env);
    env.connect(this.gainNode);

    noise.start(now);
    noise.stop(now + duration);
  }

  /**
   * Retro Astrogator Tone Glide (Jupiter 2 / Retro Future)
   * 1960s Theremin / electronic oscillator glissando
   */
  synthesizeRetroAstrogator() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx) return;

    const now = ctx.currentTime;
    const duration = 1.6;

    const osc = ctx.createOscillator();
    osc.type = 'sine';
    osc.frequency.setValueAtTime(440, now);
    osc.frequency.linearRampToValueAtTime(1180, now + 0.6);
    osc.frequency.linearRampToValueAtTime(320, now + 1.1);
    osc.frequency.linearRampToValueAtTime(660, now + duration);

    const vibrato = ctx.createOscillator();
    vibrato.type = 'sine';
    vibrato.frequency.setValueAtTime(8, now);

    const vibGain = ctx.createGain();
    vibGain.gain.setValueAtTime(25, now);
    vibrato.connect(vibGain);
    vibGain.connect(osc.frequency);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.3, now + 0.1);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    vibrato.start(now);
    osc.stop(now + duration);
    vibrato.stop(now + duration);
  }

  /**
   * HAL 9000 Logic Confirmation Chime (Discovery One)
   */
  synthesizeHalChime() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx) return;

    const now = ctx.currentTime;
    const f1 = 784; // G5
    const f2 = 523; // C5

    [0, 0.14].forEach((offset, idx) => {
      const osc = ctx.createOscillator();
      osc.type = 'sine';
      osc.frequency.setValueAtTime(idx === 0 ? f1 : f2, now + offset);

      const env = ctx.createGain();
      env.gain.setValueAtTime(0.001, now + offset);
      env.gain.linearRampToValueAtTime(0.25, now + offset + 0.01);
      env.gain.exponentialRampToValueAtTime(0.001, now + offset + 0.5);

      osc.connect(env);
      env.connect(this.gainNode);

      osc.start(now + offset);
      osc.stop(now + offset + 0.52);
    });
  }

  /**
   * Event Horizon Gravity Singularity Pulse (Deep Space)
   * Deep sub-bass dimensional warping thrum
   */
  synthesizeSingularityEngage() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx) return;

    const now = ctx.currentTime;
    const duration = 3.2;

    const sub = ctx.createOscillator();
    sub.type = 'sine';
    sub.frequency.setValueAtTime(95, now);
    sub.frequency.exponentialRampToValueAtTime(28, now + 2.2);

    const mod = ctx.createOscillator();
    mod.type = 'triangle';
    mod.frequency.setValueAtTime(14, now);
    mod.frequency.linearRampToValueAtTime(45, now + 1.8);

    const modGain = ctx.createGain();
    modGain.gain.setValueAtTime(60, now);
    mod.connect(modGain);
    modGain.connect(sub.frequency);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.65, now + 1.5);
    env.gain.exponentialRampToValueAtTime(0.0001, now + duration);

    sub.connect(env);
    env.connect(this.gainNode);

    sub.start(now);
    mod.start(now);
    sub.stop(now + duration);
    mod.stop(now + duration);
  }

  /**
   * Outlaw Afterburner Thruster Surge (Cowboy Bebop / Milano)
   */
  synthesizeAfterburner() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx) return;

    const now = ctx.currentTime;
    const duration = 2.4;

    const osc = ctx.createOscillator();
    osc.type = 'sawtooth';
    osc.frequency.setValueAtTime(80, now);
    osc.frequency.exponentialRampToValueAtTime(850, now + 0.8);
    osc.frequency.linearRampToValueAtTime(620, now + duration);

    const filter = ctx.createBiquadFilter();
    filter.type = 'bandpass';
    filter.frequency.setValueAtTime(350, now);
    filter.frequency.exponentialRampToValueAtTime(1400, now + 0.8);
    filter.Q.setValueAtTime(3.0, now);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.5, now + 0.6);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    osc.connect(filter);
    filter.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration);
  }

  /**
   * Space Station Docking Clamp Latch & Airlock Purge
   */
  synthesizeDockingClamp() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx) return;

    const now = ctx.currentTime;

    // Heavy mechanical solenoid impact
    const osc = ctx.createOscillator();
    osc.type = 'square';
    osc.frequency.setValueAtTime(380, now);
    osc.frequency.exponentialRampToValueAtTime(65, now + 0.12);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.5, now);
    env.gain.exponentialRampToValueAtTime(0.001, now + 0.25);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + 0.25);

    // Followed by pneumatic seal hiss
    setTimeout(() => {
      if (!this.am.ctx) return;
      const t = this.am.ctx.currentTime;
      const hissBuf = this.am.createNoiseBuffer('white', 1.2);
      const hiss = this.am.ctx.createBufferSource();
      hiss.buffer = hissBuf;

      const hFilter = this.am.ctx.createBiquadFilter();
      hFilter.type = 'bandpass';
      hFilter.frequency.setValueAtTime(2200, t);
      hFilter.Q.setValueAtTime(2.5, t);

      const hEnv = this.am.ctx.createGain();
      hEnv.gain.setValueAtTime(0.001, t);
      hEnv.gain.linearRampToValueAtTime(0.25, t + 0.05);
      hEnv.gain.exponentialRampToValueAtTime(0.001, t + 0.9);

      hiss.connect(hFilter);
      hFilter.connect(hEnv);
      hEnv.connect(this.gainNode);

      hiss.start(t);
      hiss.stop(t + 0.9);
    }, 180);
  }

  /**
   * Space Station Air Handler Thud (large HVAC unit cycling on)
   * Distinct from the docking clamp latch above: a dull low-frequency thump
   * (no bright metallic impact) followed by a slow-building airflow whoosh
   * rather than a short pneumatic hiss. A clamp is a single hard mechanical
   * event; an air handler is a big soft one that keeps breathing after it.
   */
  synthesizeAirHandlerThud() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx) return;

    const now = ctx.currentTime;

    // Dull low-frequency thump -- triangle, not square, and no bright impact
    // transient, so it reads as a heavy fan housing rather than a latch.
    const thump = ctx.createOscillator();
    thump.type = 'triangle';
    thump.frequency.setValueAtTime(95, now);
    thump.frequency.exponentialRampToValueAtTime(38, now + 0.22);

    const thumpEnv = ctx.createGain();
    thumpEnv.gain.setValueAtTime(0.001, now);
    thumpEnv.gain.linearRampToValueAtTime(0.42, now + 0.02);
    thumpEnv.gain.exponentialRampToValueAtTime(0.001, now + 0.4);

    // Sub-octave body for HVAC housing weight
    const sub = ctx.createOscillator();
    sub.type = 'sine';
    sub.frequency.setValueAtTime(46, now);

    const subEnv = ctx.createGain();
    subEnv.gain.setValueAtTime(0.001, now);
    subEnv.gain.linearRampToValueAtTime(0.25, now + 0.03);
    subEnv.gain.exponentialRampToValueAtTime(0.001, now + 0.45);

    thump.connect(thumpEnv);
    thumpEnv.connect(this.gainNode);
    sub.connect(subEnv);
    subEnv.connect(this.gainNode);

    thump.start(now);
    thump.stop(now + 0.4);
    sub.start(now);
    sub.stop(now + 0.45);

    // Slow-building airflow whoosh -- lowpass rather than the clamp's
    // bandpass, and a much slower attack, so it reads as a fan spinning up
    // rather than a sharp seal-release hiss.
    setTimeout(() => {
      if (!this.am.ctx) return;
      const t = this.am.ctx.currentTime;
      const airBuf = this.am.createNoiseBuffer('pink', 1.8);
      const air = this.am.ctx.createBufferSource();
      air.buffer = airBuf;

      const airFilter = this.am.ctx.createBiquadFilter();
      airFilter.type = 'lowpass';
      airFilter.frequency.setValueAtTime(420, t);
      airFilter.Q.setValueAtTime(0.7, t);

      const airEnv = this.am.ctx.createGain();
      airEnv.gain.setValueAtTime(0.001, t);
      airEnv.gain.linearRampToValueAtTime(0.22, t + 0.35);
      airEnv.gain.exponentialRampToValueAtTime(0.001, t + 1.6);

      air.connect(airFilter);
      airFilter.connect(airEnv);
      airEnv.connect(this.gainNode);

      air.start(t);
      air.stop(t + 1.6);
    }, 140);
  }

  /**
   * Ludicrous Speed Accelerator (Spaceball One / Comedy)
   */
  synthesizeLudicrousSpeed() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx) return;

    const now = ctx.currentTime;
    const duration = 3.2;

    const osc = ctx.createOscillator();
    osc.type = 'sawtooth';
    osc.frequency.setValueAtTime(60, now);
    osc.frequency.exponentialRampToValueAtTime(5400, now + 2.2);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.01, now);
    env.gain.linearRampToValueAtTime(0.4, now + 1.8);
    env.gain.exponentialRampToValueAtTime(0.0001, now + duration);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration);
  }

  /**
   * Infinite Improbability Reality-Warp Flip (Heart of Gold)
   */
  synthesizeImprobabilityFlip() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx) return;

    const now = ctx.currentTime;
    const duration = 1.8;

    const osc = ctx.createOscillator();
    osc.type = 'triangle';
    osc.frequency.setValueAtTime(1400, now);
    osc.frequency.exponentialRampToValueAtTime(180, now + 0.7);
    osc.frequency.exponentialRampToValueAtTime(2200, now + 1.3);
    osc.frequency.exponentialRampToValueAtTime(440, now + duration);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.35, now + 0.1);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration);
  }

  /**
   * Geiger Counter Click Burst (Nostromo / Mining)
   */
  synthesizeGeigerBurst() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx) return;

    const now = ctx.currentTime;
    const clicks = 8 + Math.floor(Math.random() * 8);

    for (let i = 0; i < clicks; i++) {
      const clickTime = now + (i * 0.04) + (Math.random() * 0.03);
      const osc = ctx.createOscillator();
      osc.type = 'square';
      osc.frequency.setValueAtTime(2800 + Math.random() * 800, clickTime);

      const env = ctx.createGain();
      env.gain.setValueAtTime(0.18, clickTime);
      env.gain.exponentialRampToValueAtTime(0.001, clickTime + 0.015);

      osc.connect(env);
      env.connect(this.gainNode);

      osc.start(clickTime);
      osc.stop(clickTime + 0.016);
    }
  }

  /**
   * Cheerful Door Sigh (Heart of Gold / Sirius Cybernetics Corp)
   */
  synthesizeCheerfulDoor() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx) return;

    const now = ctx.currentTime;
    const duration = 0.9;

    const osc = ctx.createOscillator();
    osc.type = 'sine';
    osc.frequency.setValueAtTime(620, now);
    osc.frequency.linearRampToValueAtTime(840, now + 0.35);
    osc.frequency.linearRampToValueAtTime(520, now + duration);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.25, now + 0.15);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration);
  }

  /**
   * Star Trek Comm Badge Confirmation Chirp
   * Iconic bright two-tone pulse in rapid sequence (784 Hz to 1397 Hz)
   */
  synthesizeCommBadge() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const tone1Freq = 784; // G5
    const tone2Freq = 1396.91; // F6

    // Pulse 1
    const osc1 = ctx.createOscillator();
    osc1.type = 'sine';
    osc1.frequency.setValueAtTime(tone1Freq, now);

    const env1 = ctx.createGain();
    env1.gain.setValueAtTime(0.001, now);
    env1.gain.linearRampToValueAtTime(0.38, now + 0.005);
    env1.gain.exponentialRampToValueAtTime(0.001, now + 0.045);

    osc1.connect(env1);
    env1.connect(this.gainNode);
    osc1.start(now);
    osc1.stop(now + 0.048);

    // Pulse 2
    const t2 = now + 0.038;
    const osc2 = ctx.createOscillator();
    osc2.type = 'sine';
    osc2.frequency.setValueAtTime(tone2Freq, t2);

    const env2 = ctx.createGain();
    env2.gain.setValueAtTime(0.001, t2);
    env2.gain.linearRampToValueAtTime(0.42, t2 + 0.006);
    env2.gain.exponentialRampToValueAtTime(0.001, t2 + 0.095);

    osc2.connect(env2);
    env2.connect(this.gainNode);
    osc2.start(t2);
    osc2.stop(t2 + 0.1);
  }

  /**
   * Starfleet Pneumatic Door Swish (Four Era Variants)
   * Bandpass-filtered white noise burst shaped per era
   */
  synthesizeDoorSwish(era = 'tng') {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    let centerFreq = 950;
    let qVal = 1.8;
    let duration = 0.45;
    let noiseType = 'white';

    switch (era) {
      case 'tos':
        centerFreq = 720;
        qVal = 1.4;
        duration = 0.38;
        break;
      case 'voyager':
        centerFreq = 1250;
        qVal = 2.4;
        duration = 0.40;
        break;
      case 'nx':
        centerFreq = 650;
        qVal = 2.0;
        duration = 0.55;
        noiseType = 'pink';
        break;
      case 'tng':
      default:
        centerFreq = 950;
        qVal = 1.8;
        duration = 0.45;
        break;
    }

    const noiseBuf = this.am.createNoiseBuffer(noiseType, duration + 0.1);
    const noise = ctx.createBufferSource();
    noise.buffer = noiseBuf;

    const bp = ctx.createBiquadFilter();
    bp.type = 'bandpass';
    bp.frequency.setValueAtTime(centerFreq * 0.8, now);
    bp.frequency.linearRampToValueAtTime(centerFreq * 1.15, now + duration * 0.4);
    bp.frequency.exponentialRampToValueAtTime(centerFreq * 0.7, now + duration);
    bp.Q.setValueAtTime(qVal, now);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.45, now + 0.03);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    noise.connect(bp);
    bp.connect(env);
    env.connect(this.gainNode);

    noise.start(now);
    noise.stop(now + duration + 0.02);
  }

  /**
   * Starfleet Bosun's Pipe Whistle (TOS Command Announce)
   * Two-tone sine glide (1800 Hz -> 2400 Hz -> 1850 Hz) with gentle tremolo
   */
  synthesizeBosunWhistle() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.85;

    const osc = ctx.createOscillator();
    osc.type = 'sine';
    osc.frequency.setValueAtTime(1800, now);
    osc.frequency.linearRampToValueAtTime(2400, now + 0.22);
    osc.frequency.setValueAtTime(2400, now + 0.48);
    osc.frequency.linearRampToValueAtTime(1850, now + 0.75);

    const tremolo = ctx.createOscillator();
    tremolo.type = 'sine';
    tremolo.frequency.setValueAtTime(6.5, now);

    const tremGain = ctx.createGain();
    tremGain.gain.setValueAtTime(0.12, now);
    tremolo.connect(tremGain);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.28, now + 0.05);
    env.gain.setValueAtTime(0.28, now + 0.65);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    tremGain.connect(env.gain);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    tremolo.start(now);
    osc.stop(now + duration);
    tremolo.stop(now + duration);
  }

  /**
   * Starfleet Sickbay Medical Monitor ECG Ping
   * Calm, periodic rhythmic vital signs pulse (1080 Hz sine, 40 ms decay)
   */
  synthesizeMedicalMonitor() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.045;

    const osc = ctx.createOscillator();
    osc.type = 'sine';
    osc.frequency.setValueAtTime(1080, now);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.32, now + 0.003);
    env.gain.exponentialRampToValueAtTime(0.0001, now + duration);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration + 0.005);
  }

  /**
   * Sevastopol Electrical Conduit Spark Transient
   * High-voltage electrical discharge arcs across damaged station bulkheads
   */
  synthesizeSevastopolSpark() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const bursts = 2 + Math.floor(Math.random() * 2);

    for (let i = 0; i < bursts; i++) {
      const offset = i * (0.015 + Math.random() * 0.02);
      const t = now + offset;
      const dur = 0.008 + Math.random() * 0.008;

      const noiseBuf = this.am.createNoiseBuffer('white', 0.05);
      const noise = ctx.createBufferSource();
      noise.buffer = noiseBuf;

      const hp = ctx.createBiquadFilter();
      hp.type = 'highpass';
      hp.frequency.setValueAtTime(3600 + Math.random() * 800, t);
      hp.Q.setValueAtTime(4.5, t);

      const env = ctx.createGain();
      env.gain.setValueAtTime(0.45, t);
      env.gain.exponentialRampToValueAtTime(0.001, t + dur);

      noise.connect(hp);
      hp.connect(env);
      env.connect(this.gainNode);

      noise.start(t);
      noise.stop(t + dur + 0.005);
    }
  }

  /**
   * Moonbase Alpha Commlock Calling Tone (Space: 1999)
   * Dual square wave pulse sequence (1100 Hz / 1500 Hz)
   */
  synthesizeCommlockTone() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;

    // Beep 1: 1100 Hz, 60 ms
    const osc1 = ctx.createOscillator();
    osc1.type = 'square';
    osc1.frequency.setValueAtTime(1100, now);

    const env1 = ctx.createGain();
    env1.gain.setValueAtTime(0.001, now);
    env1.gain.linearRampToValueAtTime(0.24, now + 0.004);
    env1.gain.setValueAtTime(0.24, now + 0.055);
    env1.gain.exponentialRampToValueAtTime(0.001, now + 0.062);

    osc1.connect(env1);
    env1.connect(this.gainNode);
    osc1.start(now);
    osc1.stop(now + 0.065);

    // Beep 2: 1500 Hz, 75 ms starting at +0.082s
    const t2 = now + 0.082;
    const osc2 = ctx.createOscillator();
    osc2.type = 'square';
    osc2.frequency.setValueAtTime(1500, t2);

    const env2 = ctx.createGain();
    env2.gain.setValueAtTime(0.001, t2);
    env2.gain.linearRampToValueAtTime(0.24, t2 + 0.004);
    env2.gain.setValueAtTime(0.24, t2 + 0.07);
    env2.gain.exponentialRampToValueAtTime(0.001, t2 + 0.078);

    osc2.connect(env2);
    env2.connect(this.gainNode);
    osc2.start(t2);
    osc2.stop(t2 + 0.082);
  }

  /**
   * Gateway Station Medical Vital Telemetry Pip (Aliens)
   * Clinical sterile 950 Hz pure sine pip (35 ms decay)
   */
  synthesizeStationMedicalPing() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.038;

    const osc = ctx.createOscillator();
    osc.type = 'sine';
    osc.frequency.setValueAtTime(950, now);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.3, now + 0.003);
    env.gain.exponentialRampToValueAtTime(0.0001, now + duration);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration + 0.005);
  }

  /**
   * Solar Radiation / Heat Shield Roar (Icarus II / Sunshine)
   * Terrifying lowpass brown noise roar with amplitude swell and crackle impulses
   */
  synthesizeSolarRoar() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 3.6;

    // Lowpass brown noise body
    const noiseBuf = this.am.createNoiseBuffer('brown', duration + 0.2);
    const noise = ctx.createBufferSource();
    noise.buffer = noiseBuf;

    const lp = ctx.createBiquadFilter();
    lp.type = 'lowpass';
    lp.frequency.setValueAtTime(120, now);
    lp.frequency.linearRampToValueAtTime(180, now + 1.5);
    lp.frequency.exponentialRampToValueAtTime(90, now + duration);
    lp.Q.setValueAtTime(2.2, now);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.72, now + 1.4);
    env.gain.setValueAtTime(0.70, now + 2.2);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    noise.connect(lp);
    lp.connect(env);
    env.connect(this.gainNode);

    noise.start(now);
    noise.stop(now + duration + 0.05);

    // Highpass solar crackle layer
    const crackleBuf = this.am.createNoiseBuffer('pink', duration);
    const crackle = ctx.createBufferSource();
    crackle.buffer = crackleBuf;

    const hp = ctx.createBiquadFilter();
    hp.type = 'highpass';
    hp.frequency.setValueAtTime(3200, now);
    hp.Q.setValueAtTime(4.0, now);

    const crackleEnv = ctx.createGain();
    crackleEnv.gain.setValueAtTime(0.001, now);
    crackleEnv.gain.linearRampToValueAtTime(0.08, now + 1.2);
    crackleEnv.gain.exponentialRampToValueAtTime(0.001, now + duration);

    crackle.connect(hp);
    hp.connect(crackleEnv);
    crackleEnv.connect(this.gainNode);

    crackle.start(now);
    crackle.stop(now + duration);
  }

  /**
   * Cryogenic Pod Depressurization Sigh (Avalon / Ark One)
   * Gas pressure relief with exponential filter decay followed by 205 Hz seal hum
   */
  synthesizeCryoDepressurize() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 1.35;

    // Pneumatic gas depressurization sigh
    const noiseBuf = this.am.createNoiseBuffer('white', 1.4);
    const noise = ctx.createBufferSource();
    noise.buffer = noiseBuf;

    const lp = ctx.createBiquadFilter();
    lp.type = 'lowpass';
    lp.frequency.setValueAtTime(1800, now);
    lp.frequency.exponentialRampToValueAtTime(280, now + 1.1);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.38, now + 0.06);
    env.gain.exponentialRampToValueAtTime(0.001, now + 1.15);

    noise.connect(lp);
    lp.connect(env);
    env.connect(this.gainNode);

    noise.start(now);
    noise.stop(now + 1.2);

    // Quiet motorized seal hum
    const hum = ctx.createOscillator();
    hum.type = 'sine';
    hum.frequency.setValueAtTime(205, now + 0.35);

    const humEnv = ctx.createGain();
    humEnv.gain.setValueAtTime(0.001, now + 0.35);
    humEnv.gain.linearRampToValueAtTime(0.18, now + 0.55);
    humEnv.gain.exponentialRampToValueAtTime(0.001, now + duration);

    hum.connect(humEnv);
    humEnv.connect(this.gainNode);

    hum.start(now + 0.35);
    hum.stop(now + duration + 0.02);
  }

  /**
   * Mid-Century Orion Nuclear Pulse Thump (USS Ascension)
   * Heavy 45 Hz lowpass square impulse with sub-bass body resonance
   */
  synthesizeOrionPulseThump() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.22;

    const osc = ctx.createOscillator();
    osc.type = 'square';
    osc.frequency.setValueAtTime(45, now);
    osc.frequency.exponentialRampToValueAtTime(24, now + 0.09);

    const lp = ctx.createBiquadFilter();
    lp.type = 'lowpass';
    lp.frequency.setValueAtTime(140, now);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.65, now);
    env.gain.exponentialRampToValueAtTime(0.001, now + 0.085);

    osc.connect(lp);
    lp.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + 0.09);

    const sub = ctx.createOscillator();
    sub.type = 'sine';
    sub.frequency.setValueAtTime(36, now);

    const subEnv = ctx.createGain();
    subEnv.gain.setValueAtTime(0.001, now);
    subEnv.gain.linearRampToValueAtTime(0.55, now + 0.01);
    subEnv.gain.exponentialRampToValueAtTime(0.0001, now + duration);

    sub.connect(subEnv);
    subEnv.connect(this.gainNode);

    sub.start(now);
    sub.stop(now + duration);
  }

  /**
   * Nutri-Matic Dedicated Tea Dispenser Gurgle (Heart of Gold)
   * Bandpass bubbling noise hops (500–1000 Hz) terminating in a short steam hiss
   */
  synthesizeTeaDispenser() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;

    // Bubbling hops
    const bubbleFreqs = [520, 840, 610, 960, 480, 730];
    bubbleFreqs.forEach((freq, i) => {
      const t = now + i * 0.11;
      const bDur = 0.09;

      const noiseBuf = this.am.createNoiseBuffer('pink', 0.12);
      const noise = ctx.createBufferSource();
      noise.buffer = noiseBuf;

      const bp = ctx.createBiquadFilter();
      bp.type = 'bandpass';
      bp.frequency.setValueAtTime(freq, t);
      bp.Q.setValueAtTime(6.0, t);

      const env = ctx.createGain();
      env.gain.setValueAtTime(0.001, t);
      env.gain.linearRampToValueAtTime(0.35, t + 0.015);
      env.gain.exponentialRampToValueAtTime(0.001, t + bDur);

      noise.connect(bp);
      bp.connect(env);
      env.connect(this.gainNode);

      noise.start(t);
      noise.stop(t + bDur + 0.01);
    });

    // Steam hiss
    const steamTime = now + 0.65;
    const steamBuf = this.am.createNoiseBuffer('white', 0.45);
    const steam = ctx.createBufferSource();
    steam.buffer = steamBuf;

    const steamFilter = ctx.createBiquadFilter();
    steamFilter.type = 'bandpass';
    steamFilter.frequency.setValueAtTime(2400, steamTime);
    steamFilter.Q.setValueAtTime(3.0, steamTime);

    const steamEnv = ctx.createGain();
    steamEnv.gain.setValueAtTime(0.001, steamTime);
    steamEnv.gain.linearRampToValueAtTime(0.28, steamTime + 0.04);
    steamEnv.gain.exponentialRampToValueAtTime(0.001, steamTime + 0.42);

    steam.connect(steamFilter);
    steamFilter.connect(steamEnv);
    steamEnv.connect(this.gainNode);

    steam.start(steamTime);
    steam.stop(steamTime + 0.45);
  }

  /**
   * British Electric Kettle Steam Whistle (HMS Camden Lock / Hyperdrive)
   * Narrow bandpass sine sweeping 1820 Hz to 2380 Hz with steady tremolo
   */
  synthesizeKettleWhistle() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 1.6;

    const osc = ctx.createOscillator();
    osc.type = 'sine';
    osc.frequency.setValueAtTime(1820, now);
    osc.frequency.exponentialRampToValueAtTime(2380, now + duration * 0.7);
    osc.frequency.linearRampToValueAtTime(2320, now + duration);

    const tremolo = ctx.createOscillator();
    tremolo.type = 'sine';
    tremolo.frequency.setValueAtTime(5.2, now);

    const tremGain = ctx.createGain();
    tremGain.gain.setValueAtTime(0.15, now);
    tremolo.connect(tremGain);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.26, now + 0.25);
    env.gain.setValueAtTime(0.26, now + 1.2);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    tremGain.connect(env.gain);

    osc.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    tremolo.start(now);
    osc.stop(now + duration);
    tremolo.stop(now + duration);
  }

  /**
   * Ludicrous Speed Plaid Alarm (Spaceball One)
   * Two-tone alternating square wave siren (440 Hz / 880 Hz)
   */
  synthesizePlaidAlarm() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const steps = 6;
    const stepDur = 0.12;

    for (let i = 0; i < steps; i++) {
      const t = now + i * stepDur;
      const freq = (i % 2 === 0) ? 440 : 880;

      const osc = ctx.createOscillator();
      osc.type = 'square';
      osc.frequency.setValueAtTime(freq, t);

      const env = ctx.createGain();
      env.gain.setValueAtTime(0.001, t);
      env.gain.linearRampToValueAtTime(0.28, t + 0.006);
      env.gain.setValueAtTime(0.28, t + stepDur - 0.01);
      env.gain.exponentialRampToValueAtTime(0.001, t + stepDur);

      osc.connect(env);
      env.connect(this.gainNode);

      osc.start(t);
      osc.stop(t + stepDur + 0.005);
    }
  }

  /**
   * Dedicated Cassette Transport Clunk & Whirr (Milano / Bebop)
   * Dual square transient click (120 Hz / 360 Hz) followed by 2200 Hz capstan tone with flutter
   */
  synthesizeCassetteTransport() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;

    // Dual square mechanical button clunk
    [120, 360].forEach((freq) => {
      const osc = ctx.createOscillator();
      osc.type = 'square';
      osc.frequency.setValueAtTime(freq, now);
      osc.frequency.exponentialRampToValueAtTime(40, now + 0.028);

      const env = ctx.createGain();
      env.gain.setValueAtTime(0.35, now);
      env.gain.exponentialRampToValueAtTime(0.001, now + 0.03);

      osc.connect(env);
      env.connect(this.gainNode);

      osc.start(now);
      osc.stop(now + 0.032);
    });

    // 12V capstan motor tone + tape flutter
    const motorTime = now + 0.04;
    const motorDur = 0.95;

    const motor = ctx.createOscillator();
    motor.type = 'sine';
    motor.frequency.setValueAtTime(2200, motorTime);

    const flutter = ctx.createOscillator();
    flutter.type = 'sine';
    flutter.frequency.setValueAtTime(8.2, motorTime);

    const flutGain = ctx.createGain();
    flutGain.gain.setValueAtTime(35, motorTime);
    flutter.connect(flutGain);
    flutGain.connect(motor.frequency);

    const motorEnv = ctx.createGain();
    motorEnv.gain.setValueAtTime(0.001, motorTime);
    motorEnv.gain.linearRampToValueAtTime(0.12, motorTime + 0.08);
    motorEnv.gain.exponentialRampToValueAtTime(0.001, motorTime + motorDur);

    motor.connect(motorEnv);
    motorEnv.connect(this.gainNode);

    motor.start(motorTime);
    flutter.start(motorTime);
    motor.stop(motorTime + motorDur);
    flutter.stop(motorTime + motorDur);

    // Tape noise bed
    const tapeBuf = this.am.createNoiseBuffer('pink', motorDur);
    const tape = ctx.createBufferSource();
    tape.buffer = tapeBuf;

    const tapeFilter = ctx.createBiquadFilter();
    tapeFilter.type = 'bandpass';
    tapeFilter.frequency.setValueAtTime(3200, motorTime);
    tapeFilter.Q.setValueAtTime(2.0, motorTime);

    const tapeEnv = ctx.createGain();
    tapeEnv.gain.setValueAtTime(0.001, motorTime);
    tapeEnv.gain.linearRampToValueAtTime(0.08, motorTime + 0.05);
    tapeEnv.gain.exponentialRampToValueAtTime(0.001, motorTime + motorDur);

    tape.connect(tapeFilter);
    tapeFilter.connect(tapeEnv);
    tapeEnv.connect(this.gainNode);

    tape.start(motorTime);
    tape.stop(motorTime + motorDur);
  }

  /**
   * Grappler Arm Servo Motor Whine (Outlaw Star / Bebop)
   * Swept triangle wave (220 Hz -> 680 Hz) through resonant bandpass filter
   */
  synthesizeGrapplerServo() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.44;

    const osc = ctx.createOscillator();
    osc.type = 'triangle';
    osc.frequency.setValueAtTime(220, now);
    osc.frequency.exponentialRampToValueAtTime(680, now + duration * 0.7);
    osc.frequency.linearRampToValueAtTime(540, now + duration);

    const bp = ctx.createBiquadFilter();
    bp.type = 'bandpass';
    bp.frequency.setValueAtTime(320, now);
    bp.frequency.exponentialRampToValueAtTime(820, now + duration * 0.7);
    bp.Q.setValueAtTime(3.2, now);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.001, now);
    env.gain.linearRampToValueAtTime(0.38, now + 0.04);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    osc.connect(bp);
    bp.connect(env);
    env.connect(this.gainNode);

    osc.start(now);
    osc.stop(now + duration + 0.01);
  }

  /**
   * True RF Radio Static Burst (The Betty / The Marauder)
   * Bandpass-filtered pink/white noise burst (300–3200 Hz) with hard-knee square gate
   */
  synthesizeRadioStatic() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;
    const duration = 0.18;

    const noiseBuf = this.am.createNoiseBuffer('pink', 0.25);
    const noise = ctx.createBufferSource();
    noise.buffer = noiseBuf;

    const bp = ctx.createBiquadFilter();
    bp.type = 'bandpass';
    bp.frequency.setValueAtTime(1400, now);
    bp.Q.setValueAtTime(1.1, now);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.42, now);
    env.gain.setValueAtTime(0.40, now + duration - 0.02);
    env.gain.exponentialRampToValueAtTime(0.001, now + duration);

    noise.connect(bp);
    bp.connect(env);
    env.connect(this.gainNode);

    noise.start(now);
    noise.stop(now + duration + 0.01);
  }

  /**
   * Magnetic Boot ("Mag-Boot") Latch (Ceres / Tycho / The Expanse)
   * Low-frequency impact thump (80 Hz click) followed by 120 Hz inductive clamp buzz
   */
  synthesizeMagBootLatch() {
    this.init();
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return;

    const now = ctx.currentTime;

    // Stage 1: Impact thump
    const thump = ctx.createOscillator();
    thump.type = 'triangle';
    thump.frequency.setValueAtTime(80, now);
    thump.frequency.exponentialRampToValueAtTime(32, now + 0.03);

    const thumpEnv = ctx.createGain();
    thumpEnv.gain.setValueAtTime(0.5, now);
    thumpEnv.gain.exponentialRampToValueAtTime(0.001, now + 0.035);

    thump.connect(thumpEnv);
    thumpEnv.connect(this.gainNode);
    thump.start(now);
    thump.stop(now + 0.038);

    // Stage 2: 120 Hz inductive clamping buzz
    const buzzTime = now + 0.025;
    const buzz = ctx.createOscillator();
    buzz.type = 'square';
    buzz.frequency.setValueAtTime(120, buzzTime);

    const buzzFilter = ctx.createBiquadFilter();
    buzzFilter.type = 'lowpass';
    buzzFilter.frequency.setValueAtTime(420, buzzTime);

    const buzzEnv = ctx.createGain();
    buzzEnv.gain.setValueAtTime(0.001, buzzTime);
    buzzEnv.gain.linearRampToValueAtTime(0.32, buzzTime + 0.01);
    buzzEnv.gain.exponentialRampToValueAtTime(0.001, buzzTime + 0.16);

    buzz.connect(buzzFilter);
    buzzFilter.connect(buzzEnv);
    buzzEnv.connect(this.gainNode);

    buzz.start(buzzTime);
    buzz.stop(buzzTime + 0.17);
  }

  /**
   * Background Loop: Periodic Medical Vital Signs Monitor (ECG)
   */
  startMedicalMonitor(intervalSeconds = 1.1) {
    this.stopMedicalMonitor();
    const tick = () => {
      this.synthesizeMedicalMonitor();
      this.medicalTimer = setTimeout(tick, intervalSeconds * 1000);
    };
    tick();
  }

  stopMedicalMonitor() {
    if (this.medicalTimer) {
      clearTimeout(this.medicalTimer);
      this.medicalTimer = null;
    }
  }

  /**
   * Background Loop: Random Electrical Sparks on Damaged Stations
   */
  startStationSparks(minIntervalMs = 4000, maxIntervalMs = 12000) {
    this.stopStationSparks();
    const scheduleNext = () => {
      const delay = minIntervalMs + Math.random() * (maxIntervalMs - minIntervalMs);
      this.sparkTimer = setTimeout(() => {
        this.synthesizeSevastopolSpark();
        scheduleNext();
      }, delay);
    };
    scheduleNext();
  }

  stopStationSparks() {
    if (this.sparkTimer) {
      clearTimeout(this.sparkTimer);
      this.sparkTimer = null;
    }
  }

  stopAllLoops() {
    this.stopMedicalMonitor();
    this.stopStationSparks();
  }
}

window.ExpandedSciFiAudioSynth = ExpandedSciFiAudioSynth;


/**
 * Layered & Staged Engine Startup and Shutdown Synthesizer
 * Synthesizes chronological multi-phase acoustic scripts for 15 distinct starship archetypes.
 */
class EngineTransitionSynth {
  constructor(audioManager) {
    this.am = audioManager;
    this.gainNode = null;
    this.activeNodes = [];
    this.activeTimeouts = [];
  }

  init() {
    if (!this.am.ctx) return;
    if (!this.gainNode) {
      this.gainNode = this.am.ctx.createGain();
      this.gainNode.gain.setValueAtTime(0.85, this.am.ctx.currentTime);
      this.gainNode.connect(this.am.compressor);
    }
  }

  stopTransitions() {
    this.activeTimeouts.forEach(t => clearTimeout(t));
    this.activeTimeouts = [];
    this.activeNodes.forEach(node => {
      try { if (node.stop) node.stop(); } catch (e) {}
      try { node.disconnect(); } catch (e) {}
    });
    this.activeNodes = [];
  }

  _tone({ type = 'sine', startFreq, endFreq, startTime, duration, startVol = 0.001, peakVol = 0.4, endVol = 0.0001, filterType = null, filterFreq = 1000, filterQ = 1.0 }) {
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return null;
    const osc = ctx.createOscillator();
    osc.type = type;
    osc.frequency.setValueAtTime(Math.max(10, startFreq), startTime);
    if (endFreq && endFreq !== startFreq) {
      osc.frequency.exponentialRampToValueAtTime(Math.max(10, endFreq), startTime + duration);
    }

    const env = ctx.createGain();
    env.gain.setValueAtTime(Math.max(0.0001, startVol), startTime);
    const attack = Math.min(0.08, duration * 0.25);
    env.gain.linearRampToValueAtTime(peakVol, startTime + attack);
    env.gain.exponentialRampToValueAtTime(Math.max(0.0001, endVol), startTime + duration);

    let lastNode = osc;
    if (filterType) {
      const filter = ctx.createBiquadFilter();
      filter.type = filterType;
      filter.frequency.setValueAtTime(filterFreq, startTime);
      filter.Q.setValueAtTime(filterQ, startTime);
      lastNode.connect(filter);
      lastNode = filter;
      this.activeNodes.push(filter);
    }

    lastNode.connect(env);
    env.connect(this.gainNode);

    osc.start(startTime);
    osc.stop(startTime + duration);

    this.activeNodes.push(osc, env);
    return osc;
  }

  _noise({ noiseType = 'pink', filterType = 'bandpass', startFreq = 800, endFreq = 800, Q = 1.5, startTime, duration, peakVol = 0.35 }) {
    const ctx = this.am.ctx;
    if (!ctx || !this.gainNode) return null;
    const buf = this.am.createNoiseBuffer(noiseType, Math.max(3, Math.ceil(duration + 1)));
    const src = ctx.createBufferSource();
    src.buffer = buf;

    const filter = ctx.createBiquadFilter();
    filter.type = filterType;
    filter.frequency.setValueAtTime(Math.max(20, startFreq), startTime);
    if (endFreq && endFreq !== startFreq) {
      filter.frequency.exponentialRampToValueAtTime(Math.max(20, endFreq), startTime + duration);
    }
    filter.Q.setValueAtTime(Q, startTime);

    const env = ctx.createGain();
    env.gain.setValueAtTime(0.0001, startTime);
    const attack = Math.min(0.12, duration * 0.3);
    env.gain.linearRampToValueAtTime(peakVol, startTime + attack);
    env.gain.exponentialRampToValueAtTime(0.0001, startTime + duration);

    src.connect(filter);
    filter.connect(env);
    env.connect(this.gainNode);

    src.start(startTime);
    src.stop(startTime + duration);

    this.activeNodes.push(src, filter, env);
    return src;
  }

  _click(startTime, freq = 140, duration = 0.035, vol = 0.4, type = 'square') {
    return this._tone({ type, startFreq: freq, endFreq: 25, startTime, duration, peakVol: vol, endVol: 0.0001 });
  }

  _sub(startTime, startFreq = 70, endFreq = 30, duration = 0.8, vol = 0.6) {
    return this._tone({ type: 'sine', startFreq, endFreq, startTime, duration, peakVol: vol, endVol: 0.0001 });
  }

  _chime(startTime, pitches = [880, 1174, 1567], step = 0.05, duration = 0.35, vol = 0.25) {
    pitches.forEach((freq, idx) => {
      const t = startTime + idx * step;
      this._tone({ type: 'sine', startFreq: freq, endFreq: freq * 1.01, startTime: t, duration, peakVol: vol, endVol: 0.0001 });
    });
  }

  playStartup(profileKey = 'galaxy', duration = 2.5) {
    this.init();
    if (!this.am.ctx) return;
    this.stopTransitions();
    const now = this.am.ctx.currentTime;
    const s = duration / 2.5;

    switch (profileKey) {
      case 'intrepid': this._startupIntrepid(now, s); break;
      case 'defiant': this._startupDefiant(now, s); break;
      case 'cardassian': this._startupCardassian(now, s); break;
      case 'tos': this._startupTOS(now, s); break;
      case 'nx': this._startupNX(now, s); break;
      case 'tardis': this._startupTardis(now, s); break;
      case 'industrial': this._startupIndustrial(now, s); break;
      case 'bioship': this._startupBioship(now, s); break;
      case 'retrofuture': this._startupRetrofuture(now, s); break;
      case 'military': this._startupMilitary(now, s); break;
      case 'deepspace': this._startupDeepSpace(now, s); break;
      case 'outlaw': this._startupOutlaw(now, s); break;
      case 'station': this._startupStation(now, s); break;
      case 'comedy': this._startupComedy(now, s); break;
      case 'galaxy':
      default:
        this._startupGalaxy(now, s);
        break;
    }
  }

  playShutdown(profileKey = 'galaxy', duration = 2.5) {
    this.init();
    if (!this.am.ctx) return;
    this.stopTransitions();
    const now = this.am.ctx.currentTime;
    const s = duration / 2.5;

    switch (profileKey) {
      case 'intrepid': this._shutdownIntrepid(now, s); break;
      case 'defiant': this._shutdownDefiant(now, s); break;
      case 'cardassian': this._shutdownCardassian(now, s); break;
      case 'tos': this._shutdownTOS(now, s); break;
      case 'nx': this._shutdownNX(now, s); break;
      case 'tardis': this._shutdownTardis(now, s); break;
      case 'industrial': this._shutdownIndustrial(now, s); break;
      case 'bioship': this._shutdownBioship(now, s); break;
      case 'retrofuture': this._shutdownRetrofuture(now, s); break;
      case 'military': this._shutdownMilitary(now, s); break;
      case 'deepspace': this._shutdownDeepSpace(now, s); break;
      case 'outlaw': this._shutdownOutlaw(now, s); break;
      case 'station': this._shutdownStation(now, s); break;
      case 'comedy': this._shutdownComedy(now, s); break;
      case 'galaxy':
      default:
        this._shutdownGalaxy(now, s);
        break;
    }
  }

  // 1. TNG GALAXY CLASS
  _startupGalaxy(now, s) {
    this._click(now, 150, 0.04, 0.45);
    this._click(now + 0.14 * s, 110, 0.03, 0.35);
    this._tone({ type: 'sine', startFreq: 60, endFreq: 140, startTime: now + 0.05 * s, duration: 0.65 * s, peakVol: 0.35 });
    this._tone({ type: 'sawtooth', startFreq: 120, endFreq: 480, startTime: now + 0.7 * s, duration: 1.1 * s, peakVol: 0.28, filterType: 'lowpass', filterFreq: 750, filterQ: 3.5 });
    this._sub(now + 0.85 * s, 65, 80, 0.95 * s, 0.55);
    this._noise({ noiseType: 'pink', filterType: 'lowpass', startFreq: 200, endFreq: 600, startTime: now + 0.9 * s, duration: 0.9 * s, peakVol: 0.25 });
    this._chime(now + 1.8 * s, [784, 1046, 1318], 0.06 * s, 0.5 * s, 0.3);
    this._sub(now + 1.8 * s, 80, 58, 0.65 * s, 0.45);
  }
  _shutdownGalaxy(now, s) {
    this._click(now, 160, 0.05, 0.5);
    this._sub(now, 85, 40, 0.65 * s, 0.6);
    this._tone({ type: 'sawtooth', startFreq: 460, endFreq: 75, startTime: now + 0.6 * s, duration: 1.2 * s, peakVol: 0.25, filterType: 'lowpass', filterFreq: 600, filterQ: 2.0 });
    this._noise({ noiseType: 'pink', filterType: 'bandpass', startFreq: 650, endFreq: 180, startTime: now + 0.75 * s, duration: 1.0 * s, peakVol: 0.28 });
    this._tone({ type: 'sine', startFreq: 75, endFreq: 24, startTime: now + 1.7 * s, duration: 0.75 * s, peakVol: 0.35 });
  }

  // 2. VOYAGER INTREPID CLASS
  _startupIntrepid(now, s) {
    this._click(now, 450, 0.025, 0.35);
    this._click(now + 0.08 * s, 680, 0.025, 0.35);
    this._tone({ type: 'triangle', startFreq: 240, endFreq: 580, startTime: now + 0.1 * s, duration: 0.6 * s, peakVol: 0.3 });
    this._tone({ type: 'sawtooth', startFreq: 320, endFreq: 1650, startTime: now + 0.7 * s, duration: 1.1 * s, peakVol: 0.35, filterType: 'bandpass', filterFreq: 1400, filterQ: 4.5 });
    this._sub(now + 0.8 * s, 70, 95, 0.9 * s, 0.45);
    this._noise({ noiseType: 'white', filterType: 'bandpass', startFreq: 1200, endFreq: 2400, startTime: now + 0.85 * s, duration: 0.9 * s, peakVol: 0.22 });
    this._chime(now + 1.8 * s, [1174, 1567, 2093], 0.05 * s, 0.45 * s, 0.28);
    this._tone({ type: 'sine', startFreq: 95, endFreq: 70, startTime: now + 1.85 * s, duration: 0.65 * s, peakVol: 0.4 });
  }
  _shutdownIntrepid(now, s) {
    this._click(now, 520, 0.03, 0.4);
    this._sub(now, 95, 50, 0.5 * s, 0.5);
    this._tone({ type: 'sawtooth', startFreq: 1600, endFreq: 140, startTime: now + 0.5 * s, duration: 1.2 * s, peakVol: 0.28, filterType: 'lowpass', filterFreq: 1200 });
    this._noise({ noiseType: 'white', filterType: 'highpass', startFreq: 1400, endFreq: 400, startTime: now + 0.6 * s, duration: 0.8 * s, peakVol: 0.25 });
    this._tone({ type: 'sine', startFreq: 140, endFreq: 30, startTime: now + 1.7 * s, duration: 0.8 * s, peakVol: 0.25 });
  }

  // 3. DEFIANT ESCORT
  _startupDefiant(now, s) {
    this._click(now, 90, 0.06, 0.6, 'square');
    this._tone({ type: 'sawtooth', startFreq: 50, endFreq: 120, startTime: now + 0.05 * s, duration: 0.6 * s, peakVol: 0.4, filterType: 'lowpass', filterFreq: 300 });
    this._sub(now + 0.65 * s, 35, 95, 1.1 * s, 0.7);
    this._tone({ type: 'sawtooth', startFreq: 180, endFreq: 740, startTime: now + 0.7 * s, duration: 1.1 * s, peakVol: 0.32, filterType: 'bandpass', filterFreq: 550, filterQ: 3.0 });
    this._chime(now + 1.8 * s, [660, 880], 0.08 * s, 0.4 * s, 0.35);
    this._sub(now + 1.8 * s, 95, 68, 0.7 * s, 0.5);
  }
  _shutdownDefiant(now, s) {
    this._click(now, 110, 0.05, 0.6);
    this._sub(now, 90, 35, 0.6 * s, 0.65);
    this._tone({ type: 'sawtooth', startFreq: 720, endFreq: 60, startTime: now + 0.6 * s, duration: 1.2 * s, peakVol: 0.3, filterType: 'lowpass', filterFreq: 450 });
    this._noise({ noiseType: 'pink', filterType: 'lowpass', startFreq: 500, endFreq: 120, startTime: now + 0.7 * s, duration: 1.0 * s, peakVol: 0.3 });
    this._tone({ type: 'sine', startFreq: 60, endFreq: 22, startTime: now + 1.7 * s, duration: 0.8 * s, peakVol: 0.35 });
  }

  // 4. CARDASSIAN / DS9
  _startupCardassian(now, s) {
    this._click(now, 85, 0.08, 0.55);
    this._tone({ type: 'triangle', startFreq: 165, endFreq: 110, startTime: now, duration: 0.7 * s, peakVol: 0.4 });
    this._sub(now + 0.7 * s, 32, 68, 1.1 * s, 0.65);
    this._tone({ type: 'sawtooth', startFreq: 80, endFreq: 260, startTime: now + 0.7 * s, duration: 1.1 * s, peakVol: 0.3, filterType: 'lowpass', filterFreq: 320 });
    this._noise({ noiseType: 'brown', filterType: 'lowpass', startFreq: 180, endFreq: 350, startTime: now + 0.8 * s, duration: 1.0 * s, peakVol: 0.3 });
    this._chime(now + 1.8 * s, [330, 440], 0.1 * s, 0.5 * s, 0.35);
  }
  _shutdownCardassian(now, s) {
    this._click(now, 95, 0.06, 0.5);
    this._sub(now, 68, 30, 0.6 * s, 0.6);
    this._tone({ type: 'sawtooth', startFreq: 250, endFreq: 40, startTime: now + 0.6 * s, duration: 1.2 * s, peakVol: 0.25, filterType: 'lowpass', filterFreq: 220 });
    this._noise({ noiseType: 'brown', filterType: 'bandpass', startFreq: 240, endFreq: 80, startTime: now + 0.7 * s, duration: 1.1 * s, peakVol: 0.25 });
    this._tone({ type: 'sine', startFreq: 40, endFreq: 20, startTime: now + 1.7 * s, duration: 0.8 * s, peakVol: 0.3 });
  }

  // 5. TOS 1960s
  _startupTOS(now, s) {
    this._click(now, 220, 0.03, 0.45);
    this._tone({ type: 'sine', startFreq: 80, endFreq: 180, startTime: now + 0.04 * s, duration: 0.6 * s, peakVol: 0.35 });
    this._tone({ type: 'sine', startFreq: 220, endFreq: 980, startTime: now + 0.65 * s, duration: 1.15 * s, peakVol: 0.32 });
    this._tone({ type: 'triangle', startFreq: 225, endFreq: 990, startTime: now + 0.65 * s, duration: 1.15 * s, peakVol: 0.2 });
    this._chime(now + 1.8 * s, [880, 1108], 0.08 * s, 0.35 * s, 0.3);
  }
  _shutdownTOS(now, s) {
    this._click(now, 260, 0.035, 0.45);
    this._tone({ type: 'sine', startFreq: 950, endFreq: 90, startTime: now + 0.5 * s, duration: 1.2 * s, peakVol: 0.3 });
    this._tone({ type: 'sine', startFreq: 2400, endFreq: 400, startTime: now + 0.6 * s, duration: 0.8 * s, peakVol: 0.15 });
    this._tone({ type: 'sine', startFreq: 90, endFreq: 25, startTime: now + 1.7 * s, duration: 0.8 * s, peakVol: 0.25 });
  }

  // 6. NX-01 PROTOTYPE
  _startupNX(now, s) {
    [0, 0.12, 0.24, 0.36, 0.48].forEach(dt => this._click(now + dt * s, 110, 0.04, 0.45));
    this._tone({ type: 'sawtooth', startFreq: 95, endFreq: 420, startTime: now + 0.6 * s, duration: 1.2 * s, peakVol: 0.32, filterType: 'lowpass', filterFreq: 600 });
    this._sub(now + 0.8 * s, 45, 75, 1.0 * s, 0.6);
    this._noise({ noiseType: 'brown', filterType: 'lowpass', startFreq: 220, endFreq: 480, startTime: now + 0.85 * s, duration: 0.95 * s, peakVol: 0.3 });
    this._click(now + 1.8 * s, 180, 0.03, 0.4);
  }
  _shutdownNX(now, s) {
    this._click(now, 95, 0.06, 0.55);
    this._sub(now, 75, 35, 0.6 * s, 0.6);
    [0.6, 0.85, 1.15, 1.5].forEach(dt => this._click(now + dt * s, 85, 0.04, 0.35));
    this._noise({ noiseType: 'pink', filterType: 'highpass', startFreq: 900, endFreq: 300, startTime: now + 0.7 * s, duration: 1.0 * s, peakVol: 0.25 });
    this._tone({ type: 'sine', startFreq: 40, endFreq: 18, startTime: now + 1.7 * s, duration: 0.8 * s, peakVol: 0.3 });
  }

  // 7. TARDIS DIMENSIONAL
  _startupTardis(now, s) {
    this._click(now, 80, 0.06, 0.55);
    this._tone({ type: 'sawtooth', startFreq: 140, endFreq: 680, startTime: now + 0.5 * s, duration: 1.3 * s, peakVol: 0.32, filterType: 'bandpass', filterFreq: 550, filterQ: 3.0 });
    this._tone({ type: 'sine', startFreq: 70, endFreq: 220, startTime: now + 0.6 * s, duration: 1.2 * s, peakVol: 0.35 });
    this._chime(now + 1.8 * s, [1046, 1318, 1567], 0.06 * s, 0.45 * s, 0.3);
  }
  _shutdownTardis(now, s) {
    this._click(now, 90, 0.05, 0.5);
    this._tone({ type: 'sawtooth', startFreq: 620, endFreq: 75, startTime: now + 0.5 * s, duration: 1.3 * s, peakVol: 0.28, filterType: 'bandpass', filterFreq: 350, filterQ: 2.0 });
    this._chime(now + 0.8 * s, [440], 0.1, 0.7 * s, 0.3);
    this._noise({ noiseType: 'pink', filterType: 'lowpass', startFreq: 350, endFreq: 80, startTime: now + 1.6 * s, duration: 0.9 * s, peakVol: 0.2 });
  }

  // 8. INDUSTRIAL FREIGHTER
  _startupIndustrial(now, s) {
    this._click(now, 75, 0.08, 0.6);
    this._noise({ noiseType: 'white', filterType: 'highpass', startFreq: 1800, endFreq: 800, startTime: now + 0.05 * s, duration: 0.4 * s, peakVol: 0.35 });
    this._tone({ type: 'sawtooth', startFreq: 55, endFreq: 290, startTime: now + 0.6 * s, duration: 1.2 * s, peakVol: 0.35, filterType: 'lowpass', filterFreq: 400 });
    this._sub(now + 0.7 * s, 35, 65, 1.1 * s, 0.7);
    this._noise({ noiseType: 'brown', filterType: 'bandpass', startFreq: 400, endFreq: 900, startTime: now + 0.8 * s, duration: 1.0 * s, peakVol: 0.3 });
    this._sub(now + 1.8 * s, 65, 40, 0.7 * s, 0.6);
  }
  _shutdownIndustrial(now, s) {
    this._click(now, 85, 0.07, 0.65);
    this._sub(now, 65, 28, 0.6 * s, 0.6);
    this._noise({ noiseType: 'white', filterType: 'lowpass', startFreq: 2400, endFreq: 400, startTime: now + 0.5 * s, duration: 1.3 * s, peakVol: 0.38 });
    this._tone({ type: 'sawtooth', startFreq: 280, endFreq: 40, startTime: now + 0.6 * s, duration: 1.2 * s, peakVol: 0.25, filterType: 'lowpass', filterFreq: 300 });
    [1.7, 1.95, 2.2].forEach(dt => this._click(now + dt * s, 320, 0.02, 0.25));
  }

  // 9. BIOSHIP
  _startupBioship(now, s) {
    this._chime(now, [784, 1174, 1567], 0.04 * s, 0.3 * s, 0.25);
    this._sub(now + 0.6 * s, 42, 28, 0.4 * s, 0.65);
    this._sub(now + 0.95 * s, 44, 28, 0.4 * s, 0.7);
    this._tone({ type: 'sine', startFreq: 260, endFreq: 540, startTime: now + 0.7 * s, duration: 1.1 * s, peakVol: 0.32 });
    this._noise({ noiseType: 'pink', filterType: 'bandpass', startFreq: 250, endFreq: 600, startTime: now + 1.7 * s, duration: 0.8 * s, peakVol: 0.3 });
  }
  _shutdownBioship(now, s) {
    this._noise({ noiseType: 'pink', filterType: 'bandpass', startFreq: 550, endFreq: 180, startTime: now, duration: 1.1 * s, peakVol: 0.35 });
    this._sub(now + 0.5 * s, 38, 25, 0.4 * s, 0.55);
    this._sub(now + 1.1 * s, 34, 22, 0.4 * s, 0.45);
    this._tone({ type: 'sine', startFreq: 480, endFreq: 180, startTime: now + 0.6 * s, duration: 1.1 * s, peakVol: 0.22 });
    this._tone({ type: 'sine', startFreq: 35, endFreq: 18, startTime: now + 1.7 * s, duration: 0.8 * s, peakVol: 0.25 });
  }

  // 10. RETROFUTURE
  _startupRetrofuture(now, s) {
    [0, 0.07, 0.14, 0.21].forEach(dt => this._click(now + dt * s, 380, 0.02, 0.3));
    this._tone({ type: 'triangle', startFreq: 95, endFreq: 580, startTime: now + 0.5 * s, duration: 1.3 * s, peakVol: 0.35, filterType: 'lowpass', filterFreq: 650 });
    this._tone({ type: 'sine', startFreq: 100, endFreq: 590, startTime: now + 0.5 * s, duration: 1.3 * s, peakVol: 0.25 });
    this._chime(now + 1.8 * s, [920], 0.1, 0.5 * s, 0.35);
  }
  _shutdownRetrofuture(now, s) {
    this._click(now, 140, 0.05, 0.55);
    this._tone({ type: 'triangle', startFreq: 550, endFreq: 65, startTime: now + 0.5 * s, duration: 1.2 * s, peakVol: 0.28 });
    this._noise({ noiseType: 'pink', filterType: 'bandpass', startFreq: 450, endFreq: 150, startTime: now + 0.6 * s, duration: 1.1 * s, peakVol: 0.22 });
    this._tone({ type: 'sine', startFreq: 3200, endFreq: 120, startTime: now + 1.7 * s, duration: 0.7 * s, peakVol: 0.2 });
  }

  // 11. MILITARY
  _startupMilitary(now, s) {
    this._click(now, 120, 0.06, 0.6);
    this._tone({ type: 'square', startFreq: 60, endFreq: 120, startTime: now, duration: 0.6 * s, peakVol: 0.35, filterType: 'lowpass', filterFreq: 250 });
    this._tone({ type: 'sawtooth', startFreq: 140, endFreq: 880, startTime: now + 0.6 * s, duration: 1.2 * s, peakVol: 0.35, filterType: 'bandpass', filterFreq: 750, filterQ: 3.0 });
    this._sub(now + 0.7 * s, 40, 85, 1.1 * s, 0.65);
    this._chime(now + 1.8 * s, [750, 750], 0.08 * s, 0.35 * s, 0.35);
  }
  _shutdownMilitary(now, s) {
    this._click(now, 150, 0.04, 0.5);
    this._chime(now + 0.05 * s, [880], 0.1, 0.3 * s, 0.35);
    this._tone({ type: 'sawtooth', startFreq: 850, endFreq: 70, startTime: now + 0.5 * s, duration: 1.3 * s, peakVol: 0.28, filterType: 'lowpass', filterFreq: 500 });
    this._noise({ noiseType: 'pink', filterType: 'lowpass', startFreq: 600, endFreq: 140, startTime: now + 0.6 * s, duration: 1.2 * s, peakVol: 0.28 });
    this._sub(now + 1.7 * s, 70, 25, 0.8 * s, 0.4);
  }

  // 12. DEEP SPACE
  _startupDeepSpace(now, s) {
    this._noise({ noiseType: 'white', filterType: 'bandpass', startFreq: 2400, endFreq: 1200, startTime: now, duration: 0.65 * s, peakVol: 0.32 });
    this._sub(now + 0.7 * s, 28, 68, 1.1 * s, 0.7);
    this._tone({ type: 'sine', startFreq: 110, endFreq: 280, startTime: now + 0.75 * s, duration: 1.1 * s, peakVol: 0.3 });
    this._chime(now + 1.8 * s, [440, 554], 0.1 * s, 0.5 * s, 0.25);
  }
  _shutdownDeepSpace(now, s) {
    this._sub(now, 68, 25, 0.7 * s, 0.65);
    this._tone({ type: 'sine', startFreq: 260, endFreq: 50, startTime: now + 0.6 * s, duration: 1.2 * s, peakVol: 0.25 });
    this._noise({ noiseType: 'brown', filterType: 'lowpass', startFreq: 200, endFreq: 40, startTime: now + 0.7 * s, duration: 1.1 * s, peakVol: 0.3 });
    this._sub(now + 1.7 * s, 35, 15, 0.8 * s, 0.25);
  }

  // 13. OUTLAW
  _startupOutlaw(now, s) {
    [0, 0.1, 0.22, 0.32, 0.44].forEach(dt => this._click(now + dt * s, 130 + Math.random() * 40, 0.035, 0.4));
    this._tone({ type: 'sawtooth', startFreq: 70, endFreq: 130, startTime: now + 0.1 * s, duration: 0.5 * s, peakVol: 0.3, filterType: 'lowpass', filterFreq: 280 });
    this._tone({ type: 'sawtooth', startFreq: 180, endFreq: 1150, startTime: now + 0.65 * s, duration: 1.15 * s, peakVol: 0.35, filterType: 'bandpass', filterFreq: 900, filterQ: 4.0 });
    this._sub(now + 0.7 * s, 45, 80, 1.1 * s, 0.65);
    this._noise({ noiseType: 'white', filterType: 'highpass', startFreq: 2800, endFreq: 1500, startTime: now + 1.8 * s, duration: 0.3 * s, peakVol: 0.35 });
  }
  _shutdownOutlaw(now, s) {
    this._click(now, 70, 0.08, 0.7, 'sawtooth');
    this._sub(now, 90, 40, 0.4 * s, 0.7);
    [0.5, 0.8, 1.15, 1.55].forEach(dt => this._click(now + dt * s, 90, 0.04, 0.35));
    this._tone({ type: 'sawtooth', startFreq: 750, endFreq: 55, startTime: now + 0.5 * s, duration: 1.3 * s, peakVol: 0.25, filterType: 'lowpass', filterFreq: 350 });
    this._noise({ noiseType: 'pink', filterType: 'lowpass', startFreq: 350, endFreq: 80, startTime: now + 1.7 * s, duration: 0.8 * s, peakVol: 0.25 });
  }

  // 14. STATION
  _startupStation(now, s) {
    this._chime(now, [587, 880], 0.08 * s, 0.35 * s, 0.3);
    this._click(now + 0.15 * s, 110, 0.05, 0.45);
    this._sub(now + 0.6 * s, 30, 65, 1.2 * s, 0.7);
    this._tone({ type: 'sawtooth', startFreq: 70, endFreq: 240, startTime: now + 0.65 * s, duration: 1.15 * s, peakVol: 0.28, filterType: 'lowpass', filterFreq: 280 });
    this._noise({ noiseType: 'pink', filterType: 'lowpass', startFreq: 200, endFreq: 500, startTime: now + 0.8 * s, duration: 1.0 * s, peakVol: 0.25 });
    this._click(now + 1.8 * s, 85, 0.06, 0.5);
  }
  _shutdownStation(now, s) {
    this._click(now, 105, 0.05, 0.5);
    this._sub(now + 0.5 * s, 65, 25, 1.4 * s, 0.55);
    this._tone({ type: 'sawtooth', startFreq: 220, endFreq: 45, startTime: now + 0.55 * s, duration: 1.3 * s, peakVol: 0.22, filterType: 'lowpass', filterFreq: 200 });
    this._noise({ noiseType: 'pink', filterType: 'lowpass', startFreq: 280, endFreq: 90, startTime: now + 1.6 * s, duration: 0.9 * s, peakVol: 0.2 });
  }

  // 15. COMEDY
  _startupComedy(now, s) {
    this._chime(now, [330, 440, 554, 659], 0.07 * s, 0.35 * s, 0.32);
    this._tone({ type: 'sawtooth', startFreq: 110, endFreq: 1400, startTime: now + 0.55 * s, duration: 1.25 * s, peakVol: 0.3, filterType: 'bandpass', filterFreq: 800, filterQ: 3.5 });
    this._sub(now + 0.7 * s, 40, 75, 1.1 * s, 0.5);
    this._chime(now + 1.8 * s, [1200], 0.1, 0.5 * s, 0.4);
  }
  _shutdownComedy(now, s) {
    this._tone({ type: 'sine', startFreq: 920, endFreq: 140, startTime: now, duration: 0.85 * s, peakVol: 0.32 });
    [0.7, 0.82, 0.96, 1.12].forEach(dt => this._click(now + dt * s, 420 + Math.random() * 200, 0.025, 0.3));
    this._noise({ noiseType: 'white', filterType: 'bandpass', startFreq: 300, endFreq: 100, startTime: now + 1.6 * s, duration: 0.6 * s, peakVol: 0.25 });
  }
}

window.EngineTransitionSynth = EngineTransitionSynth;