/**
 * useLocation Hook
 * React hook for GPS location tracking
 */

import { useState, useEffect, useCallback, useRef } from 'react';
import Geolocation from '@react-native-community/geolocation';

export function useLocation(options = {}) {
  const [location, setLocation] = useState(null);
  const [hasPermission, setHasPermission] = useState(false);
  const [isTracking, setIsTracking] = useState(false);
  const [error, setError] = useState(null);
  
  const watchIdRef = useRef(null);

  const defaultOptions = {
    enableHighAccuracy: true,
    timeout: 15000,
    maximumAge: 10000,
    distanceFilter: 10, // meters
    ...options,
  };

  /**
   * Request location permission
   */
  const requestPermission = useCallback(async () => {
    try {
      const result = await Geolocation.requestAuthorization();
      setHasPermission(result === 'granted');
      return result === 'granted';
    } catch (err) {
      setError(err.message);
      return false;
    }
  }, []);

  /**
   * Get current location (one-time)
   */
  const getCurrentLocation = useCallback(() => {
    return new Promise((resolve, reject) => {
      Geolocation.getCurrentPosition(
        (position) => {
          const loc = {
            latitude: position.coords.latitude,
            longitude: position.coords.longitude,
            altitude: position.coords.altitude,
            accuracy: position.coords.accuracy,
            heading: position.coords.heading,
            speed: position.coords.speed,
            timestamp: new Date(position.timestamp).toISOString(),
          };
          setLocation(loc);
          setError(null);
          resolve(loc);
        },
        (err) => {
          setError(err.message);
          reject(err);
        },
        defaultOptions
      );
    });
  }, [defaultOptions]);

  /**
   * Start continuous location tracking
   */
  const startTracking = useCallback(() => {
    if (watchIdRef.current) {
      return; // Already tracking
    }

    setIsTracking(true);
    
    watchIdRef.current = Geolocation.watchPosition(
      (position) => {
        const loc = {
          latitude: position.coords.latitude,
          longitude: position.coords.longitude,
          altitude: position.coords.altitude,
          accuracy: position.coords.accuracy,
          heading: position.coords.heading,
          speed: position.coords.speed,
          timestamp: new Date(position.timestamp).toISOString(),
        };
        setLocation(loc);
        setError(null);
      },
      (err) => {
        setError(err.message);
      },
      {
        ...defaultOptions,
        distanceFilter: defaultOptions.distanceFilter,
      }
    );
  }, [defaultOptions]);

  /**
   * Stop location tracking
   */
  const stopTracking = useCallback(() => {
    if (watchIdRef.current) {
      Geolocation.clearWatch(watchIdRef.current);
      watchIdRef.current = null;
    }
    setIsTracking(false);
  }, []);

  /**
   * Toggle tracking
   */
  const toggleTracking = useCallback(() => {
    if (isTracking) {
      stopTracking();
    } else {
      startTracking();
    }
  }, [isTracking, startTracking, stopTracking]);

  // Cleanup on unmount
  useEffect(() => {
    return () => {
      if (watchIdRef.current) {
        Geolocation.clearWatch(watchIdRef.current);
      }
    };
  }, []);

  return {
    // State
    location,
    hasPermission,
    isTracking,
    error,
    
    // Actions
    requestPermission,
    getCurrentLocation,
    startTracking,
    stopTracking,
    toggleTracking,
  };
}