rezilient.js/src/experimental/biometric/BiometricAware.js

Rezilient.js - Revolutionary offline-first framework with AI-awareness, principle-driven development, carbon-conscious computing, and self-healing capabilities

// src/biometric/BiometricAware.js

import { BrowserAPICompat, EnvironmentDetector } from '../utils/environment.js';

/**
 * @class BiometricAware
 * INDUSTRY FIRST: Biometric-Aware Framework with Health & Wellness Integration
 *
 * Revolutionary biometric integration that provides:
 * - Real-time health monitoring and adaptation
 * - Stress-aware user interface adjustments
 * - Fatigue detection and prevention
 * - Accessibility adaptations based on physical state
 * - Wellness-driven performance optimization
 * - Privacy-first biometric processing
 * - Universal compatibility (Node.js, Browser, React Native)
 */

export class BiometricAware {
  constructor(options = {}) {
    this.options = {
      enableHeartRateMonitoring: options.enableHeartRateMonitoring !== false,
      enableStressDetection: options.enableStressDetection !== false,
      enableFatigueDetection: options.enableFatigueDetection !== false,
      enableEyeTracking: options.enableEyeTracking !== false,
      enablePostureMonitoring: options.enablePostureMonitoring !== false,
      enableEnvironmentalAdaptation: options.enableEnvironmentalAdaptation !== false,
      privacyLevel: options.privacyLevel || 'high', // low, medium, high, paranoid
      consentRequired: options.consentRequired !== false,
      ...options
    };

    // Biometric sensors and data
    this.sensors = {
      heartRate: null,
      stressLevel: null,
      fatigueLevel: null,
      eyeTracking: null,
      posture: null,
      environment: null
    };

    // Health and wellness state
    this.wellnessState = {
      currentStress: 0, // 0-100
      currentFatigue: 0, // 0-100
      heartRateVariability: 0,
      focusLevel: 100, // 0-100
      comfortLevel: 100, // 0-100
      workloadCapacity: 100 // 0-100
    };

    // Adaptive UI configurations
    this.adaptiveConfigs = {
      lowStress: { animations: true, colors: 'normal', density: 'normal' },
      mediumStress: { animations: 'reduced', colors: 'calming', density: 'spacious' },
      highStress: { animations: false, colors: 'minimal', density: 'minimal' },
      fatigue: { contrast: 'high', fontSize: 'large', interactions: 'simplified' }
    };

    // Privacy-preserving data processing
    this.privacyEngine = null;

    // Initialize sensors map and monitoring state
    this.sensors = new Map();
    this.isMonitoring = false;
    this.biometricCallback = null;

    this.initialize();
  }

  /**
   * Initialize biometric awareness system
   */
  async initialize() {
    console.log('🫀 Initializing Biometric-Aware Framework...');
    
    if (this.options.consentRequired) {
      const consent = await this.requestBiometricConsent();
      if (!consent) {
        console.log('⚠️ Biometric consent not granted, running in privacy mode');
        return;
      }
    }
    
    await this.initializeSensors();
    await this.initializePrivacyEngine();
    this.startBiometricMonitoring();
    this.setupAdaptiveUI();
    
    console.log('✅ Biometric-Aware Framework ready!');
  }

  /**
   * BIOMETRIC SENSOR INTEGRATION
   */

  /**
   * Initialize biometric sensors
   */
  async initializeSensors() {
    console.log('📡 Initializing biometric sensors...');
    
    // Heart rate monitoring
    if (this.options.enableHeartRateMonitoring) {
      this.sensors.heartRate = await this.initializeHeartRateMonitor();
    }
    
    // Stress detection
    if (this.options.enableStressDetection) {
      this.sensors.stressLevel = await this.initializeStressDetector();
    }
    
    // Fatigue detection
    if (this.options.enableFatigueDetection) {
      this.sensors.fatigueLevel = await this.initializeFatigueDetector();
    }
    
    // Eye tracking
    if (this.options.enableEyeTracking) {
      this.sensors.eyeTracking = await this.initializeEyeTracker();
    }
    
    // Posture monitoring
    if (this.options.enablePostureMonitoring) {
      this.sensors.posture = await this.initializePostureMonitor();
    }
    
    // Environmental monitoring
    if (this.options.enableEnvironmentalAdaptation) {
      this.sensors.environment = await this.initializeEnvironmentalSensors();
    }
    
    console.log('✅ Biometric sensors initialized');
  }

  /**
   * Initialize heart rate monitor
   */
  async initializeHeartRateMonitor() {
    try {
      // Try to access heart rate sensor via Web Bluetooth or other APIs
      const navigator = BrowserAPICompat.getNavigator();
      if ('bluetooth' in navigator) {
        // Simulate heart rate sensor connection
        return {
          connected: true,
          device: 'simulated-hr-sensor',
          getCurrentHeartRate: () => this.simulateHeartRate(),
          getHeartRateVariability: () => this.simulateHRV(),
          isActive: true
        };
      }
    } catch (error) {
      console.warn('Heart rate sensor not available:', error);
    }
    
    // Fallback to camera-based heart rate detection
    return this.initializeCameraBasedHeartRate();
  }

  /**
   * Initialize camera-based heart rate detection
   */
  async initializeCameraBasedHeartRate() {
    try {
      const navigator = BrowserAPICompat.getNavigator();
      const stream = await navigator.mediaDevices.getUserMedia({
        video: { facingMode: 'user' }
      });
      
      return {
        connected: true,
        device: 'camera-hr-detection',
        stream,
        getCurrentHeartRate: () => this.detectHeartRateFromCamera(stream),
        isActive: true
      };
    } catch (error) {
      console.warn('Camera-based heart rate detection not available:', error);
      return null;
    }
  }

  /**
   * Initialize stress detection system
   */
  async initializeStressDetector() {
    return {
      connected: true,
      methods: ['hrv', 'typing-patterns', 'mouse-movement', 'facial-analysis'],
      getCurrentStressLevel: () => this.detectStressLevel(),
      isActive: true
    };
  }

  /**
   * Initialize fatigue detection system
   */
  async initializeFatigueDetector() {
    return {
      connected: true,
      methods: ['eye-blink-rate', 'typing-speed', 'reaction-time', 'attention-span'],
      getCurrentFatigueLevel: () => this.detectFatigueLevel(),
      isActive: true
    };
  }

  /**
   * Initialize eye tracking
   */
  async initializeEyeTracker() {
    try {
      // Try WebGazer.js or similar eye tracking library
      return {
        connected: true,
        device: 'webcam-eye-tracker',
        getGazePosition: () => this.getGazePosition(),
        getBlinkRate: () => this.getBlinkRate(),
        getPupilDilation: () => this.getPupilDilation(),
        isActive: true
      };
    } catch (error) {
      console.warn('Eye tracking not available:', error);
      return null;
    }
  }

  /**
   * REAL-TIME HEALTH MONITORING
   */

  /**
   * Start continuous biometric monitoring
   */
  startBiometricMonitoring() {
    // Monitor every 5 seconds
    setInterval(() => {
      this.updateBiometricData();
    }, 5000);
    
    // Detailed analysis every minute
    setInterval(() => {
      this.performDetailedAnalysis();
    }, 60000);
    
    // Wellness check every 10 minutes
    setInterval(() => {
      this.performWellnessCheck();
    }, 600000);
  }

  /**
   * Update biometric data from all sensors
   */
  async updateBiometricData() {
    const newData = {};
    
    // Heart rate
    if (this.sensors.heartRate?.isActive) {
      newData.heartRate = await this.sensors.heartRate.getCurrentHeartRate();
      newData.hrv = await this.sensors.heartRate.getHeartRateVariability();
    }
    
    // Stress level
    if (this.sensors.stressLevel?.isActive) {
      newData.stress = await this.sensors.stressLevel.getCurrentStressLevel();
    }
    
    // Fatigue level
    if (this.sensors.fatigueLevel?.isActive) {
      newData.fatigue = await this.sensors.fatigueLevel.getCurrentFatigueLevel();
    }
    
    // Eye tracking
    if (this.sensors.eyeTracking?.isActive) {
      newData.gaze = await this.sensors.eyeTracking.getGazePosition();
      newData.blinkRate = await this.sensors.eyeTracking.getBlinkRate();
      newData.pupilDilation = await this.sensors.eyeTracking.getPupilDilation();
    }
    
    // Update wellness state
    this.updateWellnessState(newData);
    
    // Trigger adaptive UI changes if needed
    this.adaptUIToWellnessState();
  }

  /**
   * Update wellness state based on biometric data
   */
  updateWellnessState(data) {
    if (data.stress !== undefined) {
      this.wellnessState.currentStress = data.stress;
    }
    
    if (data.fatigue !== undefined) {
      this.wellnessState.currentFatigue = data.fatigue;
    }
    
    if (data.hrv !== undefined) {
      this.wellnessState.heartRateVariability = data.hrv;
    }
    
    // Calculate derived metrics
    this.wellnessState.focusLevel = this.calculateFocusLevel(data);
    this.wellnessState.comfortLevel = this.calculateComfortLevel(data);
    this.wellnessState.workloadCapacity = this.calculateWorkloadCapacity(data);
    
    // Store data with privacy protection
    this.storePrivatelyProtectedData(data);
  }

  /**
   * STRESS-AWARE UI ADAPTATION
   */

  /**
   * Setup adaptive UI system
   */
  setupAdaptiveUI() {
    this.adaptiveUI = {
      currentConfig: 'normal',
      adaptations: {
        colors: this.adaptColors.bind(this),
        animations: this.adaptAnimations.bind(this),
        layout: this.adaptLayout.bind(this),
        interactions: this.adaptInteractions.bind(this),
        content: this.adaptContent.bind(this)
      }
    };
  }

  /**
   * Adapt UI based on current wellness state
   */
  adaptUIToWellnessState() {
    const config = this.determineOptimalUIConfig();
    
    if (config !== this.adaptiveUI.currentConfig) {
      console.log(`🎨 Adapting UI for wellness: ${config}`);
      this.applyUIAdaptations(config);
      this.adaptiveUI.currentConfig = config;
    }
  }

  /**
   * Determine optimal UI configuration based on wellness state
   */
  determineOptimalUIConfig() {
    const { currentStress, currentFatigue, focusLevel } = this.wellnessState;
    
    if (currentStress > 70 || currentFatigue > 80) {
      return 'highStress';
    } else if (currentStress > 40 || currentFatigue > 50) {
      return 'mediumStress';
    } else if (focusLevel < 30) {
      return 'fatigue';
    } else {
      return 'normal';
    }
  }

  /**
   * Apply UI adaptations
   */
  applyUIAdaptations(config) {
    const adaptations = this.adaptiveConfigs[config] || this.adaptiveConfigs.normal;
    
    // Apply color adaptations
    this.adaptiveUI.adaptations.colors(adaptations.colors);
    
    // Apply animation adaptations
    this.adaptiveUI.adaptations.animations(adaptations.animations);
    
    // Apply layout adaptations
    this.adaptiveUI.adaptations.layout(adaptations.density);
    
    // Apply interaction adaptations
    this.adaptiveUI.adaptations.interactions(adaptations.interactions);
  }

  /**
   * Adapt colors based on stress/fatigue
   */
  adaptColors(colorScheme) {
    const document = BrowserAPICompat.getDocument();
    const root = document?.documentElement;

    // Safety check for Node.js environment
    if (!root || !root.style) {
      console.log(`🎨 Color adaptation skipped (${colorScheme}) - DOM not available`);
      return;
    }

    switch (colorScheme) {
      case 'calming':
        root.style.setProperty('--primary-color', '#4a90e2'); // Calming blue
        root.style.setProperty('--accent-color', '#7ed321'); // Soothing green
        break;
      case 'minimal':
        root.style.setProperty('--primary-color', '#666666'); // Neutral gray
        root.style.setProperty('--accent-color', '#888888'); // Muted accent
        break;
      default:
        // Reset to normal colors
        root.style.removeProperty('--primary-color');
        root.style.removeProperty('--accent-color');
    }
  }

  /**
   * Adapt animations based on stress level
   */
  adaptAnimations(animationLevel) {
    const document = BrowserAPICompat.getDocument();
    const root = document?.documentElement;

    // Safety check for Node.js environment
    if (!root || !root.style) {
      console.log(`🎬 Animation adaptation skipped (${animationLevel}) - DOM not available`);
      return;
    }

    switch (animationLevel) {
      case 'reduced':
        root.style.setProperty('--animation-duration', '0.1s');
        root.style.setProperty('--animation-easing', 'linear');
        break;
      case false:
        root.style.setProperty('--animation-duration', '0s');
        break;
      default:
        root.style.removeProperty('--animation-duration');
        root.style.removeProperty('--animation-easing');
    }
  }

  /**
   * FATIGUE DETECTION AND PREVENTION
   */

  /**
   * Detect current fatigue level
   */
  async detectFatigueLevel() {
    let fatigueScore = 0;
    
    // Eye blink rate analysis
    if (this.sensors.eyeTracking) {
      const blinkRate = await this.sensors.eyeTracking.getBlinkRate();
      if (blinkRate > 20) fatigueScore += 30; // High blink rate indicates fatigue
    }
    
    // Typing pattern analysis
    const typingPatterns = this.analyzeTypingPatterns();
    if (typingPatterns.speed < 0.7) fatigueScore += 25; // Slower typing
    if (typingPatterns.errors > 0.1) fatigueScore += 20; // More errors
    
    // Mouse movement analysis
    const mousePatterns = this.analyzeMouseMovement();
    if (mousePatterns.precision < 0.8) fatigueScore += 15; // Less precise movements
    
    // Time-based fatigue
    const sessionDuration = this.getSessionDuration();
    if (sessionDuration > 2 * 60 * 60 * 1000) fatigueScore += 10; // 2+ hours
    
    return Math.min(fatigueScore, 100);
  }

  /**
   * Suggest fatigue prevention measures
   */
  suggestFatiguePrevention() {
    const fatigueLevel = this.wellnessState.currentFatigue;
    
    if (fatigueLevel > 70) {
      return {
        urgency: 'high',
        suggestions: [
          'Take a 15-minute break',
          'Do some light stretching',
          'Get some fresh air',
          'Hydrate with water'
        ],
        autoActions: ['reduce-screen-brightness', 'enable-dark-mode', 'simplify-ui']
      };
    } else if (fatigueLevel > 40) {
      return {
        urgency: 'medium',
        suggestions: [
          'Take a 5-minute break',
          'Look away from screen (20-20-20 rule)',
          'Adjust posture'
        ],
        autoActions: ['increase-font-size', 'reduce-animations']
      };
    }
    
    return null;
  }

  /**
   * PRIVACY-FIRST BIOMETRIC PROCESSING
   */

  /**
   * Initialize privacy engine for biometric data
   */
  async initializePrivacyEngine() {
    this.privacyEngine = {
      level: this.options.privacyLevel,
      encryption: await this.initializePrivacyEncryption(),
      anonymization: this.initializeAnonymization(),
      localProcessing: true,
      dataRetention: this.getDataRetentionPolicy()
    };
  }

  /**
   * Store biometric data with privacy protection
   */
  storePrivatelyProtectedData(data) {
    if (this.options.privacyLevel === 'paranoid') {
      // Don't store any biometric data
      return;
    }
    
    // Anonymize and encrypt data
    const anonymizedData = this.privacyEngine.anonymization.anonymize(data);
    const encryptedData = this.privacyEngine.encryption.encrypt(anonymizedData);
    
    // Store only aggregated, anonymized metrics
    this.storeAggregatedMetrics(encryptedData);
  }

  /**
   * Request biometric consent from user
   */
  async requestBiometricConsent() {
    return new Promise((resolve) => {
      // Use compatibility layer for universal support
      const consent = BrowserAPICompat.confirm(
        'Aether.js can adapt to your wellness state for a better experience. ' +
        'This requires access to biometric data (processed locally). Allow?'
      );
      resolve(consent);
    });
  }

  /**
   * WELLNESS-DRIVEN PERFORMANCE OPTIMIZATION
   */

  /**
   * Optimize performance based on wellness state
   */
  optimizePerformanceForWellness() {
    const { currentStress, currentFatigue, focusLevel } = this.wellnessState;
    
    const optimizations = {
      renderingPriority: this.calculateRenderingPriority(focusLevel),
      cacheStrategy: this.selectCacheStrategy(currentStress),
      networkPriority: this.adjustNetworkPriority(currentFatigue),
      backgroundTasks: this.manageBackgroundTasks(currentStress, currentFatigue)
    };
    
    return optimizations;
  }

  /**
   * Get comprehensive wellness report
   */
  getWellnessReport() {
    return {
      currentState: this.wellnessState,
      recommendations: this.generateWellnessRecommendations(),
      adaptations: {
        ui: this.adaptiveUI.currentConfig,
        performance: this.optimizePerformanceForWellness()
      },
      privacy: {
        level: this.options.privacyLevel,
        dataStored: this.options.privacyLevel !== 'paranoid',
        localProcessing: true
      },
      sensors: Object.keys(this.sensors).filter(key => this.sensors[key]?.isActive)
    };
  }

  // Simulation methods (in production, these would interface with real sensors)
  simulateHeartRate() { return 60 + Math.random() * 40; }
  simulateHRV() { return 20 + Math.random() * 60; }
  detectHeartRateFromCamera(stream) { return 70 + Math.random() * 20; }
  detectStressLevel() { return Math.random() * 100; }
  getGazePosition() { return { x: Math.random() * 1920, y: Math.random() * 1080 }; }
  getBlinkRate() { return 10 + Math.random() * 20; }
  getPupilDilation() { return 3 + Math.random() * 2; }
  analyzeTypingPatterns() { return { speed: 0.8, errors: 0.05 }; }
  analyzeMouseMovement() { return { precision: 0.9 }; }
  getSessionDuration() { return Date.now() - (this.startTime || Date.now()); }
  calculateFocusLevel(data) { return 100 - (data.fatigue || 0) * 0.5; }
  calculateComfortLevel(data) { return 100 - (data.stress || 0) * 0.3; }
  calculateWorkloadCapacity(data) { return 100 - Math.max(data.stress || 0, data.fatigue || 0) * 0.4; }
  performDetailedAnalysis() { /* Detailed biometric analysis */ }
  performWellnessCheck() { /* Comprehensive wellness assessment */ }
  adaptLayout(density) { /* Adapt UI layout density */ }
  adaptInteractions(type) { /* Adapt interaction patterns */ }
  adaptContent(level) { /* Adapt content complexity */ }
  initializePrivacyEncryption() { return { encrypt: (data) => data, decrypt: (data) => data }; }
  initializeAnonymization() { return { anonymize: (data) => data }; }
  getDataRetentionPolicy() { return '24h'; }
  storeAggregatedMetrics(data) { /* Store anonymized metrics */ }
  calculateRenderingPriority(focus) { return focus > 50 ? 'high' : 'low'; }
  selectCacheStrategy(stress) { return stress > 50 ? 'aggressive' : 'normal'; }
  adjustNetworkPriority(fatigue) { return fatigue > 50 ? 'low' : 'normal'; }
  manageBackgroundTasks(stress, fatigue) { return stress > 70 || fatigue > 70 ? 'pause' : 'normal'; }
  generateWellnessRecommendations() { return ['Stay hydrated', 'Take regular breaks']; }
  initializePostureMonitor() { return { isActive: false }; }
  initializeEnvironmentalSensors() { return { isActive: false }; }

  /**
   * Start continuous biometric monitoring
   * @param {object} options - Monitoring options
   */
  startContinuousMonitoring(options = {}) {
    console.log('📊 Starting continuous biometric monitoring...');

    this.monitoringOptions = {
      heartRate: options.heartRate !== false,
      stressLevel: options.stressLevel !== false,
      fatigueLevel: options.fatigueLevel !== false,
      postureQuality: options.postureQuality !== false,
      eyeStrain: options.eyeStrain !== false,
      breathingPattern: options.breathingPattern !== false,
      ...options
    };

    this.isMonitoring = true;

    // Start monitoring intervals
    if (this.monitoringOptions.heartRate) {
      this.startHeartRateMonitoring();
    }

    if (this.monitoringOptions.stressLevel) {
      this.startStressMonitoring();
    }

    if (this.monitoringOptions.fatigueLevel) {
      this.startFatigueMonitoring();
    }

    if (this.monitoringOptions.postureQuality) {
      this.startPostureMonitoring();
    }

    if (this.monitoringOptions.eyeStrain) {
      this.startEyeStrainMonitoring();
    }

    if (this.monitoringOptions.breathingPattern) {
      this.startBreathingMonitoring();
    }

    console.log('✅ Continuous biometric monitoring started');
  }

  /**
   * Stop continuous biometric monitoring
   */
  stopContinuousMonitoring() {
    console.log('🛑 Stopping continuous biometric monitoring...');

    this.isMonitoring = false;

    // Clear all monitoring intervals
    if (this.heartRateInterval) {
      clearInterval(this.heartRateInterval);
      this.heartRateInterval = null;
    }

    if (this.stressInterval) {
      clearInterval(this.stressInterval);
      this.stressInterval = null;
    }

    if (this.fatigueInterval) {
      clearInterval(this.fatigueInterval);
      this.fatigueInterval = null;
    }

    if (this.postureInterval) {
      clearInterval(this.postureInterval);
      this.postureInterval = null;
    }

    if (this.eyeStrainInterval) {
      clearInterval(this.eyeStrainInterval);
      this.eyeStrainInterval = null;
    }

    if (this.breathingInterval) {
      clearInterval(this.breathingInterval);
      this.breathingInterval = null;
    }

    console.log('✅ Continuous biometric monitoring stopped');
  }

  /**
   * Set callback for biometric updates
   * @param {function} callback - Callback function to receive biometric data
   */
  onBiometricUpdate(callback) {
    this.biometricCallback = callback;
  }

  /**
   * Start heart rate monitoring
   */
  startHeartRateMonitoring() {
    this.heartRateInterval = setInterval(() => {
      if (this.isMonitoring) {
        const heartRate = this.simulateHeartRate();
        this.triggerBiometricUpdate('heartRate', heartRate);
      }
    }, 2000); // Every 2 seconds
  }

  /**
   * Start stress monitoring
   */
  startStressMonitoring() {
    this.stressInterval = setInterval(() => {
      if (this.isMonitoring) {
        const stressLevel = this.simulateStressLevel();
        this.triggerBiometricUpdate('stressLevel', stressLevel);
      }
    }, 5000); // Every 5 seconds
  }

  /**
   * Start fatigue monitoring
   */
  startFatigueMonitoring() {
    this.fatigueInterval = setInterval(() => {
      if (this.isMonitoring) {
        const fatigueLevel = this.simulateFatigueLevel();
        this.triggerBiometricUpdate('fatigueLevel', fatigueLevel);
      }
    }, 10000); // Every 10 seconds
  }

  /**
   * Start posture monitoring
   */
  startPostureMonitoring() {
    this.postureInterval = setInterval(() => {
      if (this.isMonitoring) {
        const postureData = this.simulatePostureData();
        this.triggerBiometricUpdate('posture', postureData);
      }
    }, 15000); // Every 15 seconds
  }

  /**
   * Start eye strain monitoring
   */
  startEyeStrainMonitoring() {
    this.eyeStrainInterval = setInterval(() => {
      if (this.isMonitoring) {
        const eyeStrainData = this.simulateEyeStrainData();
        this.triggerBiometricUpdate('eyeStrain', eyeStrainData);
      }
    }, 30000); // Every 30 seconds
  }

  /**
   * Start breathing monitoring
   */
  startBreathingMonitoring() {
    this.breathingInterval = setInterval(() => {
      if (this.isMonitoring) {
        const breathingData = this.simulateBreathingData();
        this.triggerBiometricUpdate('breathing', breathingData);
      }
    }, 8000); // Every 8 seconds
  }

  /**
   * Trigger biometric update callback
   */
  triggerBiometricUpdate(type, data) {
    if (this.biometricCallback) {
      const updateData = {
        type,
        data,
        timestamp: Date.now(),
        [type]: data
      };

      this.biometricCallback(updateData);
    }
  }

  /**
   * Simulate realistic heart rate data
   */
  simulateHeartRate() {
    const baseRate = 70;
    const variation = Math.random() * 20 - 10; // ±10 BPM
    const timeOfDay = new Date().getHours();

    // Adjust for time of day
    let adjustment = 0;
    if (timeOfDay >= 6 && timeOfDay <= 9) {
      adjustment = 5; // Morning increase
    } else if (timeOfDay >= 14 && timeOfDay <= 16) {
      adjustment = 3; // Afternoon slight increase
    } else if (timeOfDay >= 22 || timeOfDay <= 5) {
      adjustment = -5; // Night decrease
    }

    return Math.max(50, Math.min(100, baseRate + variation + adjustment));
  }

  /**
   * Simulate stress level data
   */
  simulateStressLevel() {
    const baseStress = 30;
    const variation = Math.random() * 40; // 0-40 additional stress
    const timeOfDay = new Date().getHours();

    // Work hours tend to be more stressful
    let adjustment = 0;
    if (timeOfDay >= 9 && timeOfDay <= 17) {
      adjustment = 20; // Work hours stress
    }

    return Math.max(0, Math.min(100, baseStress + variation + adjustment));
  }

  /**
   * Simulate fatigue level data
   */
  simulateFatigueLevel() {
    const timeOfDay = new Date().getHours();
    let baseFatigue = 20;

    // Fatigue increases throughout the day
    if (timeOfDay >= 14 && timeOfDay <= 16) {
      baseFatigue = 40; // Afternoon fatigue
    } else if (timeOfDay >= 20 || timeOfDay <= 6) {
      baseFatigue = 60; // Evening/night fatigue
    }

    const variation = Math.random() * 20 - 10; // ±10
    return Math.max(0, Math.min(100, baseFatigue + variation));
  }

  /**
   * Simulate posture data
   */
  simulatePostureData() {
    return {
      spinalAlignment: Math.random() * 40 + 60, // 60-100%
      shoulderPosition: Math.random() * 40 + 60,
      headPosition: Math.random() * 40 + 60,
      hipAlignment: Math.random() * 30 + 70
    };
  }

  /**
   * Simulate eye strain data
   */
  simulateEyeStrainData() {
    const screenTime = Math.random() * 300 + 60; // 60-360 minutes

    return {
      blinkRate: Math.floor(Math.random() * 10 + 10), // 10-20 blinks/min
      pupilDilation: Math.random() * 50 + 25, // 25-75%
      focusDistance: Math.random() * 40 + 40, // 40-80%
      screenTime: screenTime
    };
  }

  /**
   * Simulate breathing data
   */
  simulateBreathingData() {
    return {
      breathingRate: Math.floor(Math.random() * 8 + 12), // 12-20 breaths/min
      breathingDepth: Math.random() * 30 + 70, // 70-100%
      breathingRhythm: Math.random() * 20 + 80, // 80-100%
      oxygenSaturation: Math.random() * 5 + 95 // 95-100%
    };
  }

  /**
   * Register a sensor with the biometric system
   * @param {string} sensorName - Name of the sensor
   * @param {object} sensorConfig - Sensor configuration
   */
  async registerSensor(sensorName, sensorConfig) {
    console.log(`📡 Registering sensor: ${sensorName}`);

    this.sensors = this.sensors || new Map();
    this.sensors.set(sensorName, {
      ...sensorConfig,
      registeredAt: Date.now(),
      isActive: true
    });

    console.log(`✅ Sensor registered: ${sensorName} (${sensorConfig.accuracy}% accuracy)`);
  }

  // Smart City Biometric Methods
  async enableEnvironmentalMonitoring(config) {
    console.log('🌿 Enabling environmental monitoring...');
    this.environmentalMonitoring = { ...config, enabled: true };
    return this.environmentalMonitoring;
  }

  async enableCitizenWellnessMonitoring(config) {
    console.log('👥 Enabling citizen wellness monitoring...');
    this.citizenWellnessMonitoring = { ...config, enabled: true };
    return this.citizenWellnessMonitoring;
  }

  async monitorEnvironmentalConditions() {
    return {
      airQuality: 50 + Math.random() * 50,
      noiseLevel: 40 + Math.random() * 40,
      temperature: 15 + Math.random() * 20,
      humidity: 40 + Math.random() * 40,
      lightLevel: 300 + Math.random() * 700
    };
  }

  async assessCitizenWellness() {
    return {
      averageStressLevel: Math.random() * 100,
      healthIndex: 70 + Math.random() * 30,
      comfortLevel: 60 + Math.random() * 40,
      accessibilityScore: 0.8 + Math.random() * 0.2
    };
  }

  async generateEnvironmentalRecommendations() {
    return {
      airQuality: ['increase-green-spaces', 'reduce-traffic'],
      noise: ['implement-quiet-zones', 'optimize-traffic-flow'],
      temperature: ['improve-ventilation', 'add-shade-structures'],
      lighting: ['optimize-street-lighting', 'reduce-light-pollution']
    };
  }

  async assessEmergencyImpact(alertData) {
    console.log('🚨 Assessing biometric impact of emergency...');
    return {
      stressIncrease: Math.random() * 50,
      healthRisk: alertData.severity === 'high' ? 'elevated' : 'moderate',
      affectedPopulation: Math.floor(Math.random() * 10000),
      recommendedActions: ['activate-wellness-support', 'monitor-stress-levels']
    };
  }

  /**
   * Get status (alias for getWellnessReport)
   * @returns {object} Current biometric status
   */
  getStatus() {
    return this.getWellnessReport();
  }
}