Building a React Native Steps & Sleep Tracker with HealthKit Integration

npm install react-native-health @react-native-async-storage/async-storage
npm install --save-dev @types/react-native-health
cd ios && pod install

<key>NSHealthShareUsageDescription</key>
<string>This app needs access to your health data to track your steps and sleep patterns.</string>
<key>NSHealthUpdateUsageDescription</key>
<string>This app needs to save your steps and sleep data to Apple Health.</string>

// src/types/health.ts

export interface StepsData {
  count: number;
  distance: number; // meters
  floorsAscended: number;
  floorsDescended: number;
  currentPace?: number; // min/km
  currentCadence?: number; // steps/min
  startDate: Date;
  endDate: Date;
}

export interface SleepData {
  totalSleepTime: number; // milliseconds
  timeInBed: number; // milliseconds
  sleepStages: {
    awake: number; // milliseconds
    REM: number; // milliseconds
    core: number; // milliseconds
    deep: number; // milliseconds
    unsupported?: number; // milliseconds
  };
  sleepQuality: 'excellent' | 'good' | 'fair' | 'poor';
  sleepScore: number; // 0-100
  startDate: Date;
  endDate: Date;
}

export interface SleepAnalysis {
  date: Date;
  bedtime: Date;
  wakeTime: Date;
  duration: number; // hours
  efficiency: number; // percentage
  stages: SleepStages;
  consistency: {
    sameBedtime: boolean;
    sameWakeTime: boolean;
    score: number; // 0-100
  };
}

export interface SleepStages {
  inBed: number; // percentage
  asleep: number; // percentage
  awake: number; // percentage
  core: number; // percentage
  deep: number; // percentage
  REM: number; // percentage
}

export interface DailyHealthSummary {
  date: Date;
  steps: StepsData;
  sleep: SleepAnalysis;
  stepGoal: number;
  stepGoalAchieved: boolean;
  sleepGoal: number; // hours
  sleepGoalAchieved: boolean;
}

export interface HealthInsights {
  stepTrend: 'increasing' | 'decreasing' | 'stable';
  sleepTrend: 'improving' | 'declining' | 'stable';
  recommendations: string[];
  weeklyAverage: {
    steps: number;
    sleep: number;
  };
}

// src/services/healthkitService.ts

import AppleHealthKit, {
  HealthKitPermissions,
  HealthValue,
  HealthObserver,
} from 'react-native-health';

const PERMISSIONS: HealthKitPermissions = {
  permissions: {
    read: [
      AppleHealthKit.Constants.Permissions.Steps,
      AppleHealthKit.Constants.Permissions.StepCount,
      AppleHealthKit.Constants.Permissions.DistanceWalkingRunning,
      AppleHealthKit.Constants.Permissions.FlightsClimbed,
      AppleHealthKit.Constants.Permissions.SleepAnalysis,
      AppleHealthKit.Constants.Permissions.ActivitySummary,
    ],
    write: [
      AppleHealthKit.Constants.Permissions.Steps,
      AppleHealthKit.Constants.Permissions.SleepAnalysis,
    ],
  },
};

export class HealthKitService {
  private isInitialized = false;
  private stepObservers: Array<(data: StepsData) => void> = [];
  private sleepObservers: Array<(data: SleepData) => void> = [];

  async initialize(): Promise<boolean> {
    return new Promise((resolve) => {
      AppleHealthKit.initHealthKit(PERMISSIONS, (error) => {
        if (error) {
          console.error('HealthKit init error:', error);
          resolve(false);
        } else {
          this.isInitialized = true;
          this.setupObservers();
          resolve(true);
        }
      });
    });
  }

  private setupObservers(): void {
    // Setup step observer
    AppleHealthKit.setObserver({
      type: 'Steps',
      enableBackgroundDelivery: true,
      frequency: 'immediate',
    } as HealthObserver);

    // Setup sleep observer
    AppleHealthKit.setObserver({
      type: 'SleepAnalysis',
      enableBackgroundDelivery: true,
      frequency: 'immediate',
    } as HealthObserver);
  }

  async getStepsForDate(date: Date): Promise<StepsData> {
    if (!this.isInitialized) {
      throw new Error('HealthKit not initialized');
    }

    const startOfDay = new Date(date);
    startOfDay.setHours(0, 0, 0, 0);

    const endOfDay = new Date(date);
    endOfDay.setHours(23, 59, 59, 999);

    // Get step count
    const steps = await new Promise<number>((resolve, reject) => {
      AppleHealthKit.getStepCount(
        {
          startDate: startOfDay.toISOString(),
          endDate: endOfDay.toISOString(),
          includeManuallyAdded: true,
        },
        (err, result: HealthValue) => {
          if (err) reject(err);
          else resolve(result.value || 0);
        }
      );
    });

    // Get distance
    const distance = await new Promise<number>((resolve, reject) => {
      AppleHealthKit.getDistanceWalkingRunning(
        {
          startDate: startOfDay.toISOString(),
          endDate: endOfDay.toISOString(),
        },
        (err, result: HealthValue) => {
          if (err) reject(err);
          else resolve(result.value || 0);
        }
      );
    });

    // Get floors climbed
    const floorsAscended = await new Promise<number>((resolve, reject) => {
      AppleHealthKit.getFlightsClimbed(
        {
          startDate: startOfDay.toISOString(),
          endDate: endOfDay.toISOString(),
        },
        (err, result: HealthValue) => {
          if (err) reject(err);
          else resolve(result.value || 0);
        }
      );
    });

    // Get active energy to estimate current activity
    const activeEnergy = await new Promise<number>((resolve, reject) => {
      AppleHealthKit.getActiveEnergyBurned(
        {
          startDate: new Date(Date.now() - 5 * 60 * 1000).toISOString(), // Last 5 minutes
          endDate: new Date().toISOString(),
        },
        (err, result: HealthValue) => {
          if (err) reject(err);
          else resolve(result.value || 0);
        }
      );
    });

    return {
      count: steps,
      distance: Math.round(distance),
      floorsAscended: Math.round(floorsAscended),
      floorsDescended: 0, // HealthKit doesn't provide this directly
      currentPace: steps > 0 ? Math.round((distance / 1000) / (steps / 100)) : undefined,
      currentCadence: activeEnergy > 5 ? Math.round(steps / 60) : undefined, // Estimate if active
      startDate: startOfDay,
      endDate: endOfDay,
    };
  }

  async getSleepAnalysisForDate(date: Date): Promise<SleepData> {
    if (!this.isInitialized) {
      throw new Error('HealthKit not initialized');
    }

    // Sleep often spans two days, so we look at yesterday evening to today evening
    const startOfSleepWindow = new Date(date);
    startOfSleepWindow.setHours(18, 0, 0, 0); // Start from 6 PM

    const endOfSleepWindow = new Date(date);
    endOfSleepWindow.setHours(18, 0, 0, 0);
    endOfSleepWindow.setDate(endOfSleepWindow.getDate() + 1); // Until 6 PM next day

    const sleepSamples = await new Promise<any>((resolve, reject) => {
      AppleHealthKit.getSleepSamples(
        {
          startDate: startOfSleepWindow.toISOString(),
          endDate: endOfSleepWindow.toISOString(),
          limit: 100,
        },
        (err, results) => {
          if (err) reject(err);
          else resolve(results || []);
        }
      );
    });

    if (!sleepSamples || sleepSamples.length === 0) {
      return {
        totalSleepTime: 0,
        timeInBed: 0,
        sleepStages: {
          awake: 0,
          REM: 0,
          core: 0,
          deep: 0,
        },
        sleepQuality: 'poor',
        sleepScore: 0,
        startDate: startOfSleepWindow,
        endDate: endOfSleepWindow,
      };
    }

    // Process sleep stages
    // HealthKit uses these values: 0 = inBed, 1 = asleep, 2 = awake
    let timeInBed = 0;
    let totalSleepTime = 0;
    let awakeTime = 0;

    sleepSamples.forEach((sample: any) => {
      const duration =
        new Date(sample.endDate).getTime() - new Date(sample.startDate).getTime();

      if (sample.value === 0) {
        // In bed
        timeInBed += duration;
      } else if (sample.value === 1) {
        // Asleep
        totalSleepTime += duration;
      } else if (sample.value === 2) {
        // Awake
        awakeTime += duration;
        timeInBed += duration;
      }
    });

    // HealthKit doesn't provide detailed sleep stages (REM, core, deep)
    // We'll estimate based on sleep duration
    const estimatedDeepSleep = totalSleepTime * 0.2; // ~20% deep sleep
    const estimatedREMSleep = totalSleepTime * 0.25; // ~25% REM sleep
    const estimatedCoreSleep = totalSleepTime - estimatedDeepSleep - estimatedREMSleep;

    // Calculate sleep score (0-100)
    const sleepHours = totalSleepTime / (1000 * 60 * 60);
    const sleepScore = this.calculateSleepScore(sleepHours, awakeTime / totalSleepTime);

    // Determine sleep quality
    let sleepQuality: 'excellent' | 'good' | 'fair' | 'poor';
    if (sleepScore >= 90) sleepQuality = 'excellent';
    else if (sleepScore >= 75) sleepQuality = 'good';
    else if (sleepScore >= 60) sleepQuality = 'fair';
    else sleepQuality = 'poor';

    return {
      totalSleepTime,
      timeInBed,
      sleepStages: {
        awake,
        REM: estimatedREMSleep,
        core: estimatedCoreSleep,
        deep: estimatedDeepSleep,
      },
      sleepQuality,
      sleepScore,
      startDate: new Date(sleepSamples[0].startDate),
      endDate: new Date(sleepSamples[sleepSamples.length - 1].endDate),
    };
  }

  private calculateSleepScore(
    sleepHours: number,
    awakePercentage: number
  ): number {
    // Optimal sleep is 7-9 hours
    let durationScore = 0;
    if (sleepHours >= 7 && sleepHours <= 9) {
      durationScore = 100;
    } else if (sleepHours >= 6 && sleepHours ＜ 7) {
      durationScore = 80;
    } else if (sleepHours >= 5 && sleepHours ＜ 6) {
      durationScore = 60;
    } else if (sleepHours > 9 && sleepHours <= 10) {
      durationScore = 85;
    } else {
      durationScore = 50;
    }

    // Lower awake percentage is better
    const continuityScore = Math.max(0, 100 - awakePercentage * 100);

    return Math.round((durationScore + continuityScore) / 2);
  }

  onStepsUpdate(callback: (data: StepsData) => void): void {
    this.stepObservers.push(callback);

    AppleHealthKit.observeSteps((error, results) => {
      if (!error && results) {
        const data: StepsData = {
          count: results.value || 0,
          distance: 0, // Would need separate query
          floorsAscended: 0,
          floorsDescended: 0,
          startDate: new Date(results.startDate),
          endDate: new Date(results.endDate),
        };

        this.stepObservers.forEach((cb) => cb(data));
      }
    });
  }

  onSleepUpdate(callback: (data: SleepData) => void): void {
    this.sleepObservers.push(callback);

    AppleHealthKit.observeSleepAnalysis((error, results) => {
      if (!error && results && results.length > 0) {
        // Process and notify observers
        // This is a simplified version - real implementation would process all samples
        const latestSample = results[results.length - 1];

        this.getSleepAnalysisForDate(new Date(latestSample.startDate)).then(
          (data) => {
            this.sleepObservers.forEach((cb) => cb(data));
          }
        );
      }
    });
  }

  async writeSteps(count: number, date: Date): Promise<void> {
    if (!this.isInitialized) {
      throw new Error('HealthKit not initialized');
    }

    return new Promise((resolve, reject) => {
      AppleHealthKit.saveSteps(
        {
          value: count,
          startDate: date.toISOString(),
          endDate: new Date(date.getTime() + 1000).toISOString(),
        },
        (error) => {
          if (error) reject(error);
          else resolve();
        }
      );
    });
  }

  async getWeeklySteps(startDate: Date): Promise<number[]> {
    const steps: number[] = [];

    for (let i = 0; i ＜ 7; i++) {
      const date = new Date(startDate);
      date.setDate(date.getDate() - i);

      const data = await this.getStepsForDate(date);
      steps.unshift(data.count);
    }

    return steps;
  }

  async getWeeklySleep(startDate: Date): Promise<number[]> {
    const sleepHours: number[] = [];

    for (let i = 0; i ＜ 7; i++) {
      const date = new Date(startDate);
      date.setDate(date.getDate() - i);

      const data = await this.getSleepAnalysisForDate(date);
      sleepHours.unshift(data.totalSleepTime / (1000 * 60 * 60));
    }

    return sleepHours;
  }
}

export const healthKitService = new HealthKitService();

// src/services/healthDataManager.ts

import AsyncStorage from '@react-native-async-storage/async-storage';
import { healthKitService } from './healthkitService';
import type { StepsData, SleepData, DailyHealthSummary } from '../types/health';

const CACHE_KEYS = {
  STEPS: '@wellally:steps:',
  SLEEP: '@wellally:sleep:',
  SUMMARY: '@wellally:summary:',
};

const CACHE_DURATION = 5 * 60 * 1000; // 5 minutes

export class HealthDataManager {
  private cache: Map<string, { data: any; timestamp: number }> = new Map();

  async getTodaySteps(forceRefresh = false): Promise<StepsData> {
    const today = new Date();
    const cacheKey = `${CACHE_KEYS.STEPS}${today.toDateString()}`;

    if (!forceRefresh) {
      const cached = await this.getCachedData<StepsData>(cacheKey);
      if (cached) {
        return cached;
      }
    }

    const data = await healthKitService.getStepsForDate(today);
    await this.setCachedData(cacheKey, data);

    return data;
  }

  async getTodaySleep(forceRefresh = false): Promise<SleepData> {
    const today = new Date();
    const cacheKey = `${CACHE_KEYS.SLEEP}${today.toDateString()}`;

    if (!forceRefresh) {
      const cached = await this.getCachedData<SleepData>(cacheKey);
      if (cached) {
        return cached;
      }
    }

    const data = await healthKitService.getSleepAnalysisForDate(today);
    await this.setCachedData(cacheKey, data);

    return data;
  }

  async getDailySummary(date: Date, forceRefresh = false): Promise<DailyHealthSummary> {
    const cacheKey = `${CACHE_KEYS.SUMMARY}${date.toDateString()}`;

    if (!forceRefresh) {
      const cached = await this.getCachedData<DailyHealthSummary>(cacheKey);
      if (cached) {
        return cached;
      }
    }

    const steps = await healthKitService.getStepsForDate(date);
    const sleep = await healthKitService.getSleepAnalysisForDate(date);

    const summary: DailyHealthSummary = {
      date,
      steps,
      sleep: {
        date,
        bedtime: sleep.startDate,
        wakeTime: sleep.endDate,
        duration: sleep.totalSleepTime / (1000 * 60 * 60),
        efficiency: (sleep.totalSleepTime / sleep.timeInBed) * 100,
        stages: {
          inBed: 100,
          asleep: (sleep.totalSleepTime / sleep.timeInBed) * 100,
          awake: (sleep.sleepStages.awake / sleep.timeInBed) * 100,
          core: (sleep.sleepStages.core / sleep.totalSleepTime) * 100,
          deep: (sleep.sleepStages.deep / sleep.totalSleepTime) * 100,
          REM: (sleep.sleepStages.REM / sleep.totalSleepTime) * 100,
        },
        consistency: {
          sameBedtime: false,
          sameWakeTime: false,
          score: 0,
        },
      },
      stepGoal: 10000,
      stepGoalAchieved: steps.count >= 10000,
      sleepGoal: 8,
      sleepGoalAchieved:
        sleep.totalSleepTime / (1000 * 60 * 60) >= 7 &&
        sleep.totalSleepTime / (1000 * 60 * 60) <= 9,
    };

    await this.setCachedData(cacheKey, summary);

    return summary;
  }

  async getWeeklySummaries(endDate: Date): Promise<DailyHealthSummary[]> {
    const summaries: DailyHealthSummary[] = [];

    for (let i = 6; i >= 0; i--) {
      const date = new Date(endDate);
      date.setDate(date.getDate() - i);
      date.setHours(0, 0, 0, 0);

      const summary = await this.getDailySummary(date);
      summaries.push(summary);
    }

    return summaries;
  }

  private async getCachedData<T>(key: string): Promise<T | null> {
    // Check memory cache first
    const memCached = this.cache.get(key);
    if (memCached && Date.now() - memCached.timestamp < CACHE_DURATION) {
      return memCached.data as T;
    }

    // Check persistent cache
    try {
      const json = await AsyncStorage.getItem(key);
      if (json) {
        const { data, timestamp } = JSON.parse(json);

        if (Date.now() - timestamp < CACHE_DURATION) {
          // Restore to memory cache
          this.cache.set(key, { data, timestamp });
          return data as T;
        }
      }
    } catch (error) {
      console.error('Error reading from cache:', error);
    }

    return null;
  }

  private async setCachedData<T>(key: string, data: T): Promise<void> {
    const timestamp = Date.now();
    const cacheData = { data, timestamp };

    // Store in memory
    this.cache.set(key, cacheData);

    // Store persistently
    try {
      await AsyncStorage.setItem(key, JSON.stringify(cacheData));
    } catch (error) {
      console.error('Error writing to cache:', error);
    }
  }

  async clearCache(): Promise<void> {
    this.cache.clear();

    const keys = await AsyncStorage.getAllKeys();
    const wellallyKeys = keys.filter((key) => key.startsWith('@wellally:'));
    await AsyncStorage.multiRemove(wellallyKeys);
  }
}

export const healthDataManager = new HealthDataManager();

// src/services/insightsEngine.ts

import type { DailyHealthSummary, HealthInsights } from '../types/health';

export class InsightsEngine {
  generateInsights(summaries: DailyHealthSummary[]): HealthInsights {
    const recentSummaries = summaries.slice(-7); // Last 7 days

    return {
      stepTrend: this.analyzeStepTrend(recentSummaries),
      sleepTrend: this.analyzeSleepTrend(recentSummaries),
      recommendations: this.generateRecommendations(recentSummaries),
      weeklyAverage: {
        steps: this.calculateAverageSteps(recentSummaries),
        sleep: this.calculateAverageSleep(recentSummaries),
      },
    };
  }

  private analyzeStepTrend(summaries: DailyHealthSummary[]): 'increasing' | 'decreasing' | 'stable' {
    if (summaries.length ＜ 3) return 'stable';

    const firstHalf = summaries.slice(0, Math.floor(summaries.length / 2));
    const secondHalf = summaries.slice(Math.floor(summaries.length / 2));

    const firstAvg = this.calculateAverageSteps(firstHalf);
    const secondAvg = this.calculateAverageSteps(secondHalf);

    const changePercent = ((secondAvg - firstAvg) / firstAvg) * 100;

    if (changePercent > 10) return 'increasing';
    if (changePercent < -10) return 'decreasing';
    return 'stable';
  }

  private analyzeSleepTrend(summaries: DailyHealthSummary[]): 'improving' | 'declining' | 'stable' {
    if (summaries.length ＜ 3) return 'stable';

    const recentScores = summaries.slice(-3).map((s) => s.sleep.efficiency);
    const olderScores = summaries.slice(-6, -3).map((s) => s.sleep.efficiency);

    const recentAvg = recentScores.reduce((a, b) => a + b, 0) / recentScores.length;
    const olderAvg = olderScores.reduce((a, b) => a + b, 0) / olderScores.length;

    const changePercent = ((recentAvg - olderAvg) / olderAvg) * 100;

    if (changePercent > 5) return 'improving';
    if (changePercent < -5) return 'declining';
    return 'stable';
  }

  private generateRecommendations(summaries: DailyHealthSummary[]): string[] {
    const recommendations: string[] = [];

    const avgSteps = this.calculateAverageSteps(summaries);
    const avgSleep = this.calculateAverageSleep(summaries);

    // Step recommendations
    if (avgSteps ＜ 7000) {
      recommendations.push(
        'Try to increase your daily steps. Aim for at least 7,000 steps per day.'
      );
    } else if (avgSteps ＜ 10000) {
      recommendations.push(
        "You're doing well! Try to reach 10,000 steps daily for optimal health benefits."
      );
    } else {
      recommendations.push(
        "Excellent work maintaining an active lifestyle! Keep up the great step count."
      );
    }

    // Sleep recommendations
    if (avgSleep ＜ 7) {
      recommendations.push(
        'Your sleep duration is below the recommended 7-9 hours. Try to go to bed 30 minutes earlier.'
      );
    } else if (avgSleep > 9) {
      recommendations.push(
        'You\'re sleeping more than 9 hours. While individual needs vary, oversleeping can sometimes indicate health issues.'
      );
    } else {
      recommendations.push(
        'Your sleep duration is within the optimal range. Maintain your current sleep schedule.'
      );
    }

    // Sleep efficiency recommendations
    const avgEfficiency =
      summaries.reduce((sum, s) => sum + s.sleep.efficiency, 0) / summaries.length;

    if (avgEfficiency ＜ 85) {
      recommendations.push(
        'Your sleep efficiency could be improved. Consider reducing screen time before bed and maintaining a consistent sleep schedule.'
      );
    }

    // Consistency recommendations
    const consistentBedtime = this.checkBedtimeConsistency(summaries);
    const consistentWakeTime = this.checkWakeTimeConsistency(summaries);

    if (!consistentBedtime) {
      recommendations.push(
        'Try to maintain a consistent bedtime, even on weekends. This helps regulate your body\'s internal clock.'
      );
    }

    if (!consistentWakeTime) {
      recommendations.push(
        'Wake up at the same time every day to improve sleep quality and make mornings easier.'
      );
    }

    return recommendations;
  }

  private calculateAverageSteps(summaries: DailyHealthSummary[]): number {
    if (summaries.length === 0) return 0;

    const total = summaries.reduce((sum, s) => sum + s.steps.count, 0);
    return Math.round(total / summaries.length);
  }

  private calculateAverageSleep(summaries: DailyHealthSummary[]): number {
    if (summaries.length === 0) return 0;

    const total = summaries.reduce((sum, s) => sum + s.sleep.duration, 0);
    return parseFloat((total / summaries.length).toFixed(1));
  }

  private checkBedtimeConsistency(summaries: DailyHealthSummary[]): boolean {
    if (summaries.length ＜ 3) return true;

    const bedtimes = summaries
      .map((s) => s.sleep.bedtime.getHours() * 60 + s.sleep.bedtime.getMinutes())
      .sort((a, b) => a - b);

    const range = bedtimes[bedtimes.length - 1] - bedtimes[0];
    return range <= 60; // Within 1 hour
  }

  private checkWakeTimeConsistency(summaries: DailyHealthSummary[]): boolean {
    if (summaries.length ＜ 3) return true;

    const wakeTimes = summaries
      .map((s) => s.sleep.wakeTime.getHours() * 60 + s.sleep.wakeTime.getMinutes())
      .sort((a, b) => a - b);

    const range = wakeTimes[wakeTimes.length - 1] - wakeTimes[0];
    return range <= 60; // Within 1 hour
  }
}

export const insightsEngine = new InsightsEngine();

// src/hooks/useStepsAndSleep.ts

import { useState, useEffect, useCallback } from 'react';
import { healthDataManager } from '../services/healthDataManager';
import { healthKitService } from '../services/healthkitService';
import { insightsEngine } from '../services/insightsEngine';
import type { StepsData, SleepData, DailyHealthSummary, HealthInsights } from '../types/health';

export const useStepsAndSleep = () => {
  const [steps, setSteps] = useState<StepsData | null>(null);
  const [sleep, setSleep] = useState<SleepData | null>(null);
  const [summaries, setSummaries] = useState<DailyHealthSummary[]>([]);
  const [insights, setInsights] = useState<HealthInsights | null>(null);
  const [isLoading, setIsLoading] = useState(true);
  const [error, setError] = useState<Error | null>(null);
  const [isAuthorized, setIsAuthorized] = useState(false);

  const initialize = useCallback(async () => {
    try {
      setIsLoading(true);
      setError(null);

      const authorized = await healthKitService.initialize();
      setIsAuthorized(authorized);

      if (!authorized) {
        throw new Error('HealthKit authorization failed');
      }

      // Load initial data
      await refreshData();

      // Setup observers
      healthKitService.onStepsUpdate((data) => {
        setSteps(data);
      });

      healthKitService.onSleepUpdate((data) => {
        setSleep(data);
      });
    } catch (err) {
      setError(err as Error);
    } finally {
      setIsLoading(false);
    }
  }, []);

  const refreshData = useCallback(async () => {
    try {
      setIsLoading(true);
      setError(null);

      const today = new Date();

      // Get today's data
      const [todaySteps, todaySleep] = await Promise.all([
        healthDataManager.getTodaySteps(true),
        healthDataManager.getTodaySleep(true),
      ]);

      setSteps(todaySteps);
      setSleep(todaySleep);

      // Get weekly summaries
      const weeklySummaries = await healthDataManager.getWeeklySummaries(today);
      setSummaries(weeklySummaries);

      // Generate insights
      const healthInsights = insightsEngine.generateInsights(weeklySummaries);
      setInsights(healthInsights);
    } catch (err) {
      setError(err as Error);
    } finally {
      setIsLoading(false);
    }
  }, []);

  useEffect(() => {
    initialize();
  }, [initialize]);

  return {
    steps,
    sleep,
    summaries,
    insights,
    isLoading,
    error,
    isAuthorized,
    refreshData,
  };
};

// src/components/StepsSleepDashboard.tsx

import React, { useMemo } from 'react';
import {
  View,
  Text,
  StyleSheet,
  ScrollView,
  ActivityIndicator,
  Dimensions,
} from 'react-native';
import { useStepsAndSleep } from '../hooks/useStepsAndSleep';
import { LineChart } from 'react-native-chart-kit';

const { width } = Dimensions.get('window');

export const StepsSleepDashboard: React.FC = () => {
  const { steps, sleep, summaries, insights, isLoading, error, refreshData } =
    useStepsAndSleep();

  const chartData = useMemo(() => {
    return {
      labels: summaries.map((s) =>
        s.date.toLocaleDateString('en-US', { weekday: 'short' })
      ),
      datasets: [
        {
          data: summaries.map((s) => Math.round(s.steps.count / 1000)),
          color: (opacity = 1) => `rgba(74, 144, 226, ${opacity})`,
        },
      ],
    };
  }, [summaries]);

  const sleepChartData = useMemo(() => {
    return {
      labels: summaries.map((s) =>
        s.date.toLocaleDateString('en-US', { weekday: 'short' })
      ),
      datasets: [
        {
          data: summaries.map((s) => parseFloat(s.sleep.duration.toFixed(1))),
          color: (opacity = 1) => `rgba(155, 89, 182, ${opacity})`,
        },
      ],
    };
  }, [summaries]);

  if (isLoading) {
    return (
      <View style={styles.loadingContainer}>
        <ActivityIndicator size="large" color="#4A90E2" />
        <Text style={styles.loadingText}>Loading your health data...</Text>
      </View>
    );
  }

  if (error) {
    return (
      <View style={styles.errorContainer}>
        <Text style={styles.errorText}>Error: {error.message}</Text>
      </View>
    );
  }

  return (
    <ScrollView style={styles.container} refreshControl={{ onRefresh: refreshData }}>
      {/* Steps Overview */}
      <View style={styles.section}>
        <Text style={styles.sectionTitle}>Steps Today</Text>
        <View style={styles.metricCard}>
          <Text style={styles.metricValue}>
            {steps?.count.toLocaleString() || '0'}
          </Text>
          <Text style={styles.metricLabel}>steps</Text>
          <View style={styles.progressContainer}>
            <View style={styles.progressBar}>
              <View
                style={[
                  styles.progressFill,
                  { width: `${Math.min(((steps?.count || 0) / 10000) * 100, 100)}%` },
                ]}
              />
            </View>
            <Text style={styles.progressText}>
              {Math.min(((steps?.count || 0) / 10000) * 100, 100).toFixed(0)}% of goal
            </Text>
          </View>
        </View>

        {steps && (
          <View style={styles.detailsRow}>
            <View style={styles.detailItem}>
              <Text style={styles.detailValue}>
                {(steps.distance / 1000).toFixed(1)} km
              </Text>
              <Text style={styles.detailLabel}>Distance</Text>
            </View>
            <View style={styles.detailItem}>
              <Text style={styles.detailValue}>{steps.floorsAscended}</Text>
              <Text style={styles.detailLabel}>Floors</Text>
            </View>
          </View>
        )}
      </View>

      {/* Sleep Overview */}
      <View style={styles.section}>
        <Text style={styles.sectionTitle}>Sleep Last Night</Text>
        <View style={styles.metricCard}>
          <Text style={styles.metricValue}>
            {((sleep?.totalSleepTime || 0) / (1000 * 60 * 60)).toFixed(1)}h
          </Text>
          <Text style={styles.metricLabel}>
            {sleep?.sleepQuality || 'Poor'} quality
          </Text>
          <View style={styles.sleepScoreContainer}>
            <View style={styles.sleepScoreBar}>
              <View
                style={[
                  styles.sleepScoreFill,
                  {
                    width: `${sleep?.sleepScore || 0}%`,
                    backgroundColor:
                      (sleep?.sleepScore || 0) >= 90
                        ? '#27ae60'
                        : (sleep?.sleepScore || 0) >= 75
                        ? '#f39c12'
                        : '#e74c3c',
                  },
                ]}
              />
            </View>
            <Text style={styles.sleepScoreText}>
              Sleep Score: {sleep?.sleepScore || 0}/100
            </Text>
          </View>
        </View>

        {sleep && (
          <View style={styles.sleepStagesContainer}>
            <Text style={styles.sleepStagesTitle}>Sleep Stages</Text>
            <SleepStageBar
              label="Deep"
              percentage={(sleep.sleepStages.deep / sleep.totalSleepTime) * 100}
              color="#3498db"
            />
            <SleepStageBar
              label="REM"
              percentage={(sleep.sleepStages.REM / sleep.totalSleepTime) * 100}
              color="#9b59b6"
            />
            <SleepStageBar
              label="Core"
              percentage={(sleep.sleepStages.core / sleep.totalSleepTime) * 100}
              color="#1abc9c"
            />
            <SleepStageBar
              label="Awake"
              percentage={(sleep.sleepStages.awake / sleep.totalSleepTime) * 100}
              color="#e74c3c"
            />
          </View>
        )}
      </View>

      {/* Weekly Steps Chart */}
      <View style={styles.section}>
        <Text style={styles.sectionTitle}>Weekly Steps</Text>
        <LineChart
          data={chartData}
          width={width - 40}
          height={220}
          chartConfig={{
            backgroundColor: '#1cc910',
            backgroundGradientFrom: '#eff3ff',
            backgroundGradientTo: '#efefef',
            decimalPlaces: 0,
            color: (opacity = 1) => `rgba(74, 144, 226, ${opacity})`,
            style: {
              borderRadius: 16,
            },
          }}
          bezier
          style={styles.chart}
        />
      </View>

      {/* Weekly Sleep Chart */}
      <View style={styles.section}>
        <Text style={styles.sectionTitle}>Weekly Sleep (hours)</Text>
        <LineChart
          data={sleepChartData}
          width={width - 40}
          height={220}
          chartConfig={{
            backgroundColor: '#1cc910',
            backgroundGradientFrom: '#f3e5f5',
            backgroundGradientTo: '#efefef',
            decimalPlaces: 1,
            color: (opacity = 1) => `rgba(155, 89, 182, ${opacity})`,
            style: {
              borderRadius: 16,
            },
          }}
          bezier
          style={styles.chart}
        />
      </View>

      {/* Insights */}
      {insights && (
        <View style={styles.section}>
          <Text style={styles.sectionTitle}>Weekly Insights</Text>
          <View style={styles.insightsCard}>
            <View style={styles.insightItem}>
              <Text style={styles.insightLabel}>Step Trend</Text>
              <Text
                style={[
                  styles.insightValue,
                  insights.stepTrend === 'increasing'
                    ? styles.positive
                    : insights.stepTrend === 'decreasing'
                    ? styles.negative
                    : styles.neutral,
                ]}
              >
                {insights.stepTrend.charAt(0).toUpperCase() + insights.stepTrend.slice(1)}
              </Text>
            </View>
            <View style={styles.insightItem}>
              <Text style={styles.insightLabel}>Sleep Trend</Text>
              <Text
                style={[
                  styles.insightValue,
                  insights.sleepTrend === 'improving'
                    ? styles.positive
                    : insights.sleepTrend === 'declining'
                    ? styles.negative
                    : styles.neutral,
                ]}
              >
                {insights.sleepTrend.charAt(0).toUpperCase() + insights.sleepTrend.slice(1)}
              </Text>
            </View>
            <View style={styles.insightItem}>
              <Text style={styles.insightLabel}>Weekly Avg Steps</Text>
              <Text style={styles.insightValue}>
                {insights.weeklyAverage.steps.toLocaleString()}
              </Text>
            </View>
            <View style={styles.insightItem}>
              <Text style={styles.insightLabel}>Weekly Avg Sleep</Text>
              <Text style={styles.insightValue}>{insights.weeklyAverage.sleep}h</Text>
            </View>
          </View>

          {insights.recommendations.length > 0 && (
            <View style={styles.recommendationsCard}>
              <Text style={styles.recommendationsTitle}>Recommendations</Text>
              {insights.recommendations.map((rec, index) => (
                <View key={index} style={styles.recommendationItem}>
                  <Text style={styles.recommendationText}>{rec}</Text>
                </View>
              ))}
            </View>
          )}
        </View>
      )}
    </ScrollView>
  );
};

const SleepStageBar: React.FC<{
  label: string;
  percentage: number;
  color: string;
}> = ({ label, percentage, color }) => (
  <View style={styles.sleepStageBar}>
    <Text style={styles.sleepStageLabel}>{label}</Text>
    <View style={styles.sleepStageBarContainer}>
      <View
        style={[
          styles.sleepStageBarFill,
          { width: `${Math.min(percentage, 100)}%`, backgroundColor: color },
        ]}
      />
      <Text style={styles.sleepStagePercentage}>{percentage.toFixed(0)}%</Text>
    </View>
  </View>
);

const styles = StyleSheet.create({
  container: {
    flex: 1,
    backgroundColor: '#f5f5f5',
  },
  loadingContainer: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
    backgroundColor: '#f5f5f5',
  },
  loadingText: {
    marginTop: 16,
    fontSize: 16,
    color: '#666',
  },
  errorContainer: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
    backgroundColor: '#f5f5f5',
    padding: 20,
  },
  errorText: {
    fontSize: 16,
    color: '#e74c3c',
    textAlign: 'center',
  },
  section: {
    backgroundColor: '#fff',
    margin: 16,
    padding: 16,
    borderRadius: 12,
    shadowColor: '#000',
    shadowOffset: { width: 0, height: 2 },
    shadowOpacity: 0.1,
    shadowRadius: 4,
    elevation: 3,
  },
  sectionTitle: {
    fontSize: 20,
    fontWeight: 'bold',
    color: '#333',
    marginBottom: 16,
  },
  metricCard: {
    backgroundColor: '#f9f9f9',
    padding: 20,
    borderRadius: 12,
    alignItems: 'center',
  },
  metricValue: {
    fontSize: 48,
    fontWeight: 'bold',
    color: '#333',
  },
  metricLabel: {
    fontSize: 16,
    color: '#666',
    marginTop: 8,
    textTransform: 'uppercase',
  },
  progressContainer: {
    width: '100%',
    marginTop: 16,
  },
  progressBar: {
    height: 8,
    backgroundColor: '#e0e0e0',
    borderRadius: 4,
    overflow: 'hidden',
  },
  progressFill: {
    height: '100%',
    backgroundColor: '#4A90E2',
  },
  progressText: {
    fontSize: 14,
    color: '#666',
    marginTop: 8,
    textAlign: 'center',
  },
  detailsRow: {
    flexDirection: 'row',
    marginTop: 16,
    justifyContent: 'space-around',
  },
  detailItem: {
    alignItems: 'center',
  },
  detailValue: {
    fontSize: 24,
    fontWeight: 'bold',
    color: '#333',
  },
  detailLabel: {
    fontSize: 14,
    color: '#666',
    marginTop: 4,
  },
  sleepScoreContainer: {
    width: '100%',
    marginTop: 16,
  },
  sleepScoreBar: {
    height: 8,
    backgroundColor: '#e0e0e0',
    borderRadius: 4,
    overflow: 'hidden',
  },
  sleepScoreFill: {
    height: '100%',
  },
  sleepScoreText: {
    fontSize: 14,
    color: '#666',
    marginTop: 8,
    textAlign: 'center',
  },
  sleepStagesContainer: {
    marginTop: 16,
  },
  sleepStagesTitle: {
    fontSize: 16,
    fontWeight: 'bold',
    color: '#333',
    marginBottom: 12,
  },
  sleepStageBar: {
    marginBottom: 12,
  },
  sleepStageLabel: {
    fontSize: 14,
    color: '#666',
    marginBottom: 4,
  },
  sleepStageBarContainer: {
    height: 24,
    backgroundColor: '#f0f0f0',
    borderRadius: 12,
    overflow: 'hidden',
    position: 'relative',
  },
  sleepStageBarFill: {
    height: '100%',
  },
  sleepStagePercentage: {
    position: 'absolute',
    right: 8,
    top: 2,
    fontSize: 14,
    fontWeight: 'bold',
    color: '#333',
  },
  chart: {
    marginVertical: 8,
    borderRadius: 16,
  },
  insightsCard: {
    backgroundColor: '#f9f9f9',
    borderRadius: 12,
    padding: 16,
  },
  insightItem: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    paddingVertical: 8,
    borderBottomWidth: 1,
    borderBottomColor: '#e0e0e0',
  },
  insightLabel: {
    fontSize: 16,
    color: '#666',
  },
  insightValue: {
    fontSize: 16,
    fontWeight: 'bold',
  },
  positive: {
    color: '#27ae60',
  },
  negative: {
    color: '#e74c3c',
  },
  neutral: {
    color: '#7f8c8d',
  },
  recommendationsCard: {
    backgroundColor: '#e8f5e9',
    borderRadius: 12,
    padding: 16,
    marginTop: 16,
  },
  recommendationsTitle: {
    fontSize: 16,
    fontWeight: 'bold',
    color: '#2e7d32',
    marginBottom: 12,
  },
  recommendationItem: {
    paddingVertical: 4,
  },
  recommendationText: {
    fontSize: 14,
    color: '#1b5e20',
    lineHeight: 20,
  },
});

// src/services/backgroundHealthSync.ts

import BackgroundJob from 'react-native-background-job';
import { healthDataManager } from './healthDataManager';
import { healthKitService } from './healthkitService';

export class BackgroundHealthSync {
  private static JOB_ID = 'wellally_health_sync';

  static async initialize(): Promise<void> {
    BackgroundJob.on(this.JOB_ID, async () => {
      console.log('Background health sync started');

      try {
        // Refresh today's data
        await healthDataManager.getTodaySteps(true);
        await healthDataManager.getTodaySleep(true);

        // Keep observers active
        healthKitService.onStepsUpdate((data) => {
          console.log('Background step update:', data.count);
        });

        console.log('Background health sync completed');
      } catch (error) {
        console.error('Background sync error:', error);
      }
    });
  }

  static async schedule(): Promise<void> {
    await BackgroundJob.schedule({
      jobKey: this.JOB_ID,
      period: 900000, // 15 minutes
      exact: false,
      allowWhileIdle: true,
      allowExecutionInForeground: true,
    });
  }

  static async cancel(): Promise<void> {
    await BackgroundJob.cancel(this.JOB_ID);
  }
}