/*

     File: TapView.m

 Abstract: UIView subclass that can highlight itself when locally or remotely tapped.

  Version: 2.1

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 */

#import "TapView.h"

@import QuartzCore;

static const CGFloat kActivationInset = 10.0f;

@interface TapView ()

@property (nonatomic, assign, readwrite) BOOL   localTouch;

@end

@implementation TapView

- (id)initWithCoder:(NSCoder *)aDecoder

{

    self = [super initWithCoder:aDecoder];

    if (self != nil) {

        [self commonInit];

    }

    return self;

}

- (id)initWithFrame:(CGRect)frame

{

    self = [super initWithFrame:frame];

    if (self != nil) {

        [self commonInit];

    }

    return self;

}

- (void)commonInit

{

    assert( ! self.isMultipleTouchEnabled );

    self.layer.borderColor = [[UIColor darkGrayColor] CGColor];

    // Observe ourself to learn about someone changing the remoteTouch property.

    [self addObserver:self forKeyPath:@"remoteTouch" options:0 context:&self->_remoteTouch];

}

- (void)dealloc

{

    [self removeObserver:self forKeyPath:@"remoteTouch" context:&self->_remoteTouch];

}

- (void)updateLayerBorder

{

    self.layer.borderWidth = (self.localTouch || self.remoteTouch) ? kActivationInset : 0.0f;

}

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context

{

    if (context == &self->_remoteTouch) {

        // If the remoteTouch property changes, redraw.

        [self updateLayerBorder];

    } else {

        [super observeValueForKeyPath:keyPath ofObject:object change:change context:context];

    }

}

- (void)resetTouches

    // See comment in header.

{

    [self localTouchUpNotify:NO];

    if (self.remoteTouch) {

        self.remoteTouch = NO;

    }

}

#pragma mark - Touch tracking

- (void)localTouchDown

{

    if ( ! self.localTouch ) {

        id <TapViewDelegate>  strongDelegate;

        self.localTouch = YES;

        [self updateLayerBorder];

        strongDelegate = self.delegate;

        if ([strongDelegate respondsToSelector:@selector(tapViewLocalTouchDown:)]) {

            [strongDelegate tapViewLocalTouchDown:self];

        }

    }

}

- (void)localTouchUpNotify:(BOOL)notify

{

    if ( self.localTouch ) {

        self.localTouch = NO;

        [self updateLayerBorder];

        if (notify) {

            id <TapViewDelegate>  strongDelegate;

            strongDelegate = self.delegate;

            if ([strongDelegate respondsToSelector:@selector(tapViewLocalTouchUp:)]) {

                [strongDelegate tapViewLocalTouchUp:self];

            }

        }

    }

}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event

{

    #pragma unused(touches)

    #pragma unused(event)

    [self localTouchDown];

}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event

{

    #pragma unused(touches)

    #pragma unused(event)

    [self localTouchUpNotify:YES];

}

- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event

{

    #pragma unused(touches)

    #pragma unused(event)

    [self localTouchUpNotify:YES];

}

@end