import * as Location from 'expo-location';
import { GPSInfo } from '../types';

export async function requestLocationPermissions(): Promise<boolean> {
  try {
    const { status } = await Location.requestForegroundPermissionsAsync();
    return status === 'granted';
  } catch (error) {
    console.error('Error requesting location permissions:', error);
    return false;
  }
}

export async function getCurrentGPS(): Promise<GPSInfo | null> {
  try {
    const hasPermission = await requestLocationPermissions();
    if (!hasPermission) return null;

    const location = await Location.getCurrentPositionAsync({
      accuracy: Location.Accuracy.Balanced,
    });

    const { latitude, longitude } = location.coords;
    let locality = 'UNKNOWN LOCATION';
    let country = '';

    try {
      const geocode = await Location.reverseGeocodeAsync({ latitude, longitude });
      if (geocode && geocode.length > 0) {
        const address = geocode[0];
        // Combine city, region, street or subregion to form a retro looking place string
        locality = address.subregion || address.city || address.district || address.region || 'LOCAL REGION';
        locality = locality.toUpperCase();
        country = (address.country || '').toUpperCase();
      }
    } catch (e) {
      console.warn('Reverse geocoding failed, using coordinates only:', e);
    }

    return {
      latitude,
      longitude,
      locality,
      country,
      timestamp: location.timestamp,
    };
  } catch (error) {
    console.error('Error fetching GPS info:', error);
    return null;
  }
}

export async function reverseGeocode(latitude: number, longitude: number): Promise<string | null> {
  try {
    const geo = await Location.reverseGeocodeAsync({ latitude, longitude });
    if (geo && geo.length > 0) {
      return (geo[0].subregion || geo[0].city || geo[0].region || '').toUpperCase() || null;
    }
  } catch (e) {
    console.warn('Reverse geocode failed:', e);
  }
  return null;
}

export function formatCoordinate(val: number, type: 'lat' | 'lon'): string {
  const absolute = Math.abs(val);
  const degrees = Math.floor(absolute);
  const minutes = Math.floor((absolute - degrees) * 60);
  const seconds = ((absolute - degrees - minutes / 60) * 3600).toFixed(2);
  const direction = type === 'lat' ? (val >= 0 ? 'N' : 'S') : (val >= 0 ? 'E' : 'W');
  
  return `${degrees}° ${minutes}' ${seconds}" ${direction}`;
}