/*

 Copyright (C) 2016 Apple Inc. All Rights Reserved.

 See LICENSE.txt for this sample’s licensing information

 Abstract:

 The custom annotation view to display a region that is being monitored.

 */

#import "RegionAnnotationView.h"

#import "RegionAnnotation.h"

@interface RegionAnnotationView() {

}

@property (strong, nonatomic) MKCircle *radiusOverlay;

@property (assign, nonatomic) BOOL isRadiusUpdated;

@end

@implementation RegionAnnotationView

// Initialize the annotation view object. This is the designated initializer.

- (instancetype)initWithAnnotation:(id <MKAnnotation>)annotation {

    self = [super initWithAnnotation:annotation reuseIdentifier:[annotation title]];    

    if (self) {     

        self.canShowCallout = YES;

        self.multipleTouchEnabled = NO;

        self.draggable = YES;

        self.animatesDrop = YES;

        _map = nil;

        _theAnnotation = (RegionAnnotation *)annotation;

        self.pinColor = MKPinAnnotationColorPurple;

        _radiusOverlay = [MKCircle circleWithCenterCoordinate:_theAnnotation.coordinate radius:_theAnnotation.radius];

        [_map addOverlay:self.radiusOverlay];

    }

    return self;    

}

- (void)removeRadiusOverlay {

    // Find the overlay for this annotation view and remove it if it has the same coordinates.

    for (id overlay in [self.map overlays]) {

        if ([overlay isKindOfClass:[MKCircle class]]) {                     

            MKCircle *circleOverlay = (MKCircle *)overlay;          

            CLLocationCoordinate2D coord = circleOverlay.coordinate;

            if (coord.latitude == self.theAnnotation.coordinate.latitude && coord.longitude == self.theAnnotation.coordinate.longitude) {

                [self.map removeOverlay:overlay];

            }           

        }

    }

    self.isRadiusUpdated = NO;

}

// Update the circular overlay if the radius has changed.

- (void)updateRadiusOverlay {

    if (!self.isRadiusUpdated) {

        self.isRadiusUpdated = YES;

        [self removeRadiusOverlay]; 

        self.canShowCallout = NO;

        [self.map addOverlay:[MKCircle circleWithCenterCoordinate:self.theAnnotation.coordinate radius:self.theAnnotation.radius]];

        self.canShowCallout = YES;      

    }

}

@end