//: Playground - noun: a place where people can play

import UIKit
import PlaygroundSupport
import ObjectiveC

let image = UIImage(named: "berlinerdom.jpg")!
let imageView = UIImageView(image: image)
imageView.frame.size.width = 540
imageView.frame.size.height = 363
let effectView = UIVisualEffectView(effect: UIBlurEffect(style: .light))
effectView.frame.size.width = 540//360
effectView.frame.size.height = 363//242
effectView.center = imageView.center
imageView.addSubview(effectView)

PlaygroundPage.current.liveView = imageView
PlaygroundPage.current.needsIndefiniteExecution = true


func properties(_ instance: NSObject) {
    var count = UInt32()
    let classToInspect = type(of: instance)
    let properties : UnsafeMutablePointer<objc_property_t?> = class_copyPropertyList(classToInspect, &count)
    var propertyNames = [String]()
    let intCount = Int(count)
    for i in 0..<intCount {
        let property : objc_property_t = properties[i]!
        guard let propertyName = NSString(utf8String: property_getName(property)) as? String else {
            debugPrint("Couldn't unwrap property name for \(property)")
            break
        }
        
        let v = instance.value(forKey: propertyName)
        print(v!)
        propertyNames.append(propertyName)
    }
    
    free(properties)
    print(propertyNames)
}

extension UIVisualEffectView {
    
    fileprivate var filterLayer: CALayer? {
        return layer.sublayers?.first
    }
    
    fileprivate var blurFilter: NSObject? {
        return filterLayer?
            .filters?.flatMap({ $0 as? NSObject })
            .first(where: { $0.value(forKey: "name") as? String == "gaussianBlur" })
    }

    fileprivate var saturationFilter: NSObject? {
        return filterLayer?
            .filters?.flatMap({ $0 as? NSObject })
            .first(where: { $0.value(forKey: "name") as? String == "colorSaturate" })
    }

    fileprivate var matrixFilter: NSObject? {
        return filterLayer?
            .filters?.flatMap({ $0 as? NSObject })
            .first(where: { $0.value(forKey: "name") as? String == "colorMatrix" })
    }

    var blurRadius: CGFloat? {
        get {
            return blurFilter?.value(forKey: kCIInputRadiusKey) as? CGFloat
        }
        set {
            blurFilter?.setValue(newValue, forKey: kCIInputRadiusKey)
        }
    }
    
    var enableBlur: Bool {
        get {
            let dimLayer = layer.sublayers?.last?.opacity != 0
            return blurRadius != 0 && dimLayer
        }
        set {
            blurRadius = 0
            layer.sublayers?.last?.opacity = newValue ? 1 : 0
        }
    }
    
    /// the same as saturation amount 1
    var enableSaturation: Bool {
        get {
            return saturationFilter?.value(forKey: "enabled") as? Bool ?? false
        }
        set {
            saturationFilter?.setValue(newValue, forKey: "enabled")
        }
    }
    
    var enableColorMatrix: Bool {
        get {
            return matrixFilter?.value(forKey: "enabled") as? Bool ?? false
        }
        set {
            matrixFilter?.setValue(newValue, forKey: "enabled")
        }
    }
    
    var saturationAmount: CGFloat? {
        get {
            return saturationFilter?.value(forKey: "inputAmount") as? CGFloat
        }
        set {
            saturationFilter?.setValue(newValue, forKey: "inputAmount")
        }
    }
    
    var scale: CGFloat? {
        get {
            return filterLayer?.value(forKey: "scale") as? CGFloat
        }
        set {
            filterLayer?.setValue(newValue, forKey: "scale")
        }
    }
}

func animateScale() {
    effectView.filterLayer?.removeAllAnimations()
    effectView.enableSaturation = false
    effectView.enableBlur = false
    
    let anim = CABasicAnimation(keyPath: "scale")
    anim.fromValue = 0.05
    anim.toValue = 1
    anim.duration = 5
    anim.repeatCount = .infinity
    effectView.scale = 1
    effectView.filterLayer?.add(anim, forKey: "scale")
}

func animateBlur() {
    effectView.filterLayer?.removeAllAnimations()
    
    effectView.enableSaturation = false
    effectView.scale = 1
    effectView.enableBlur = false
    
    CATransaction.begin()
    CATransaction.setAnimationDuration(5)
    var anim = CABasicAnimation(keyPath: "filters.gaussianBlur.inputRadius")
    anim.fromValue = 30
    anim.toValue = 0
    anim.repeatCount = .infinity
    effectView.filterLayer?.add(anim, forKey: "filters.gaussianBlur.inputRadius")

    anim = CABasicAnimation(keyPath: "opacity")
    anim.fromValue = 1
    anim.toValue = 0
    anim.repeatCount = .infinity
    effectView.layer.sublayers?.last?.add(anim, forKey: "opacity")
    CATransaction.commit()
}

func animateBlurUIKit() {
    effectView.filterLayer?.removeAllAnimations()

    UIView.animate(withDuration: 5, delay: 0, options: .repeat, animations: {
        effectView.effect = nil
    }, completion: nil)
}

func animateSaturation() {
    effectView.filterLayer?.removeAllAnimations()
    effectView.enableBlur = false
    effectView.scale = 1
    
    let anim = CABasicAnimation(keyPath: "filters.colorSaturate.inputAmount")
    anim.fromValue = 0
    anim.toValue = 1.8
    anim.duration = 5
    anim.repeatCount = .infinity
    effectView.saturationAmount = 1.8
    effectView.filterLayer?.add(anim, forKey: "filters.colorSaturate.inputAmount")
}

//animateScale()
//animateBlur()
//animateBlurUIKit()
//animateSaturation()

effectView.enableSaturation = false
effectView.scale = 0.5
effectView.blurRadius = 5