UIViewExtensions

//
//  UIViewExtensions.swift
//  Singles
//
//  Created by Cory D. Wiles on 2/19/15.
//  Copyright (c) 2015 Cory WIles. All rights reserved.
//

import UIKit

/// Need to subclass NSObject or you get nasty crash (methodSignatureForSelector)

private class ClosureWrapper: NSObject, NSCopying {

    var closure: (() -> Void)?
    
     convenience init(closure: (() -> Void)?) {

        self.init()
        self.closure = closure?
    }
    
    func copyWithZone(zone: NSZone) -> AnyObject {

        var wrapper: ClosureWrapper = ClosureWrapper()
        wrapper.closure = closure?

        return wrapper
    }
}

extension UIView {
    
    private struct AssociatedKeys {

        static var SNGLSActionHandlerTapBlockKey   = "sngls_ActionHandlerTapBlockKey"
        static var SNGLSActionHandlerTapGestureKey = "sngls_ActionHandlerTapGestureKey"
    }
    
    var tapAction: (() -> Void)? {
        
        get {

            if let cl = objc_getAssociatedObject(self, &AssociatedKeys.SNGLSActionHandlerTapBlockKey) as? ClosureWrapper {
                return cl.closure
            }
            
            return nil
        }
        set {
            objc_setAssociatedObject(
                self,
                &AssociatedKeys.SNGLSActionHandlerTapBlockKey,
                ClosureWrapper(newValue),
                UInt(OBJC_ASSOCIATION_RETAIN_NONATOMIC)
            )
        }
    }
    
    var tapGesture: UITapGestureRecognizer? {
    
        get {
            
            if let gesture: UITapGestureRecognizer = objc_getAssociatedObject(self, &AssociatedKeys.SNGLSActionHandlerTapGestureKey) as? UITapGestureRecognizer {
                
                return gesture
            }
            
            return nil
        }
        set {
            
            objc_setAssociatedObject(self, &AssociatedKeys.SNGLSActionHandlerTapGestureKey, (newValue), UInt(OBJC_ASSOCIATION_RETAIN_NONATOMIC))
        }
    }

    func sngls_setTapAction(completionBlock:() -> Void) {

        self.tapAction  = completionBlock
        self.tapGesture = UITapGestureRecognizer(target: self, action: Selector("sngls__handleActionForTapGesture:"))

        self.addGestureRecognizer(self.tapGesture!)
    }
    

    // MARK: Semi Private Methods

    func sngls__handleActionForTapGesture(gesture: UITapGestureRecognizer) -> Void {

        if (gesture.state == UIGestureRecognizerState.Ended) {

            if let action: ClosureWrapper = objc_getAssociatedObject(self, &AssociatedKeys.SNGLSActionHandlerTapBlockKey) as? ClosureWrapper {
                action.closure!()
            }
        }
    }
}