//
//  NV_ViewController.m
//

#import "NV_ViewController.h"
#import <GoogleMaps/GoogleMaps.h>

@interface NV_ViewController ()

@end

@implementation NV_ViewController {
    GMSMapView *gmsMapView;
    CLLocationManager *locationManagerMonitor;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.


    if ([self _checkIfLocationIsEnabled]) {

        CLLocation *location = [locationManagerMonitor location];

        GMSCameraPosition *camera = [GMSCameraPosition cameraWithLatitude:location.coordinate.latitude longitude:location.coordinate.longitude zoom:1];

        gmsMapView = [[GMSMapView alloc] initWithFrame:CGRectZero];
        gmsMapView.delegate = self;
        gmsMapView.myLocationEnabled = YES;
        gmsMapView.settings.myLocationButton = YES;
        self.view = gmsMapView;

        [gmsMapView setCamera:camera];
        [gmsMapView animateToCameraPosition:[GMSCameraPosition cameraWithTarget:gmsMapView.camera.target zoom:16]];

        NSSet *monitoredRegions = [locationManagerMonitor monitoredRegions];
        if (monitoredRegions) {
            [monitoredRegions enumerateObjectsUsingBlock:^(CLRegion *region, BOOL *stop)
             {
                 NSString *identifier = region.identifier;
                 NSLog(@"%@", identifier);

                 [locationManagerMonitor stopMonitoringForRegion:region];
             }];
        }

        [locationManagerMonitor startMonitoringSignificantLocationChanges];
    }
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}



#pragma mark -
#pragma mark Custom Methods
- (BOOL)_checkIfLocationIsEnabled
{
    if (![CLLocationManager locationServicesEnabled]) {
        [self _showAlertWithMessage:@"location is not enabled"];
        return NO;
    }

    locationManagerMonitor = [[CLLocationManager alloc] init];
    [locationManagerMonitor setDelegate:self];
    [locationManagerMonitor setDesiredAccuracy:kCLLocationAccuracyBest];
    [locationManagerMonitor setDistanceFilter:kCLDistanceFilterNone];

    return YES;
}

- (void)_showAlertWithMessage:(NSString *)message
{
    UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"Alert" message:message delegate:self cancelButtonTitle:nil otherButtonTitles:@"OK", nil];
    [alertView show];
}


//http://hayageek.com/ios-geofencing-api/
- (NSNumber*)_calculateDistanceInMetersBetweenCoord:(CLLocationCoordinate2D)coord1 coord:(CLLocationCoordinate2D)coord2
{
    NSInteger nRadius = 6371; // Earth's radius in Kilometers
    double latDiff = (coord2.latitude - coord1.latitude) * (M_PI/180);
    double lonDiff = (coord2.longitude - coord1.longitude) * (M_PI/180);
    double lat1InRadians = coord1.latitude * (M_PI/180);
    double lat2InRadians = coord2.latitude * (M_PI/180);
    double nA = pow ( sin(latDiff/2), 2 ) + cos(lat1InRadians) * cos(lat2InRadians) * pow ( sin(lonDiff/2), 2 );
    double nC = 2 * atan2( sqrt(nA), sqrt( 1 - nA ));
    double nD = nRadius * nC;
    // convert to meters
    return @(nD*1000);
}



#pragma mark -
#pragma mark GMSMapViewDelegates
- (void)mapView:(GMSMapView *)mapView didLongPressAtCoordinate:(CLLocationCoordinate2D)coordinate
{
    NSLog(@"add marker");

    NSString *identifier = [[NSUUID UUID] UUIDString];

    GMSMarker *marker = [[GMSMarker alloc] init];
    [marker setAppearAnimation:kGMSMarkerAnimationPop];
    marker.position = coordinate;
    marker.title = identifier;
    marker.snippet = [[NSString alloc] initWithFormat:@"%f - %f", coordinate.latitude, coordinate.longitude];
    marker.map = gmsMapView;


    [locationManagerMonitor startUpdatingLocation];

    CLCircularRegion *region = [[CLCircularRegion alloc] initWithCenter:coordinate radius:200 identifier:identifier];
    region.notifyOnEntry = YES;
    region.notifyOnExit = YES;
    [locationManagerMonitor startMonitoringForRegion:region];

    [locationManagerMonitor stopUpdatingLocation];

    GMSCircle *regionCircle = [[GMSCircle alloc] init];
    regionCircle.radius = region.radius;
    regionCircle.position = coordinate;
    regionCircle.fillColor = [UIColor colorWithWhite:0.7 alpha:0.5];
    regionCircle.strokeWidth = 3;
    regionCircle.strokeColor = [UIColor blueColor];
    regionCircle.map = gmsMapView;
}

- (void)mapView:(GMSMapView *)mapView didTapInfoWindowOfMarker:(GMSMarker *)marker
{
    CLLocationCoordinate2D userLocation = [[gmsMapView myLocation] coordinate];

    NSNumber *distance = [self _calculateDistanceInMetersBetweenCoord:marker.position coord:userLocation];

    CLCircularRegion *region = [regions objectAtIndex:0];
    CLLocationCoordinate2D coordinate = [[gmsMapView myLocation] coordinate];

    //print distance
    NSLog(@"%@", distance);
}

- (BOOL)didTapMyLocationButtonForMapView:(GMSMapView *)mapView
{
    CLLocationCoordinate2D userLocation = [[gmsMapView myLocation] coordinate];
    NSLog(@"Actual %f - %f", userLocation.latitude, userLocation.longitude);

    GMSCameraPosition *camera = [GMSCameraPosition cameraWithLatitude:userLocation.latitude longitude:userLocation.longitude zoom:16];
    [gmsMapView setCamera:camera];


    return YES;
}



#pragma mark -
#pragma mark CLLocationManagerDelegates
- (void)locationManager:(CLLocationManager *)manager didEnterRegion:(CLRegion *)region
{
    NSLog(@"enter: %@", region.identifier);
    [self _showAlertWithMessage:@"ENTER !!!"];
}

- (void)locationManager:(CLLocationManager *)manager didExitRegion:(CLRegion *)region
{
    NSLog(@"exit: %@", region.identifier);
}



@end