Swiftgram/submodules/ContextUI/Sources/ContextControllerSourceNode.swift

import Foundation
import AsyncDisplayKit
import Display

public final class ContextControllerSourceNode: ASDisplayNode {
    private var contextGesture: ContextGesture?
    
    public var isGestureEnabled: Bool = true {
        didSet {
            self.contextGesture?.isEnabled = self.isGestureEnabled
        }
    }
    public var activated: ((ContextGesture) -> Void)?
    
    override public func didLoad() {
        super.didLoad()
        
        let contextGesture = ContextGesture(target: self, action: nil)
        self.contextGesture = contextGesture
        self.view.addGestureRecognizer(contextGesture)
        
        contextGesture.activationProgress = { [weak self] progress, update in
            guard let strongSelf = self, !strongSelf.bounds.width.isZero else {
                return
            }
            let minScale: CGFloat = (strongSelf.bounds.width - 20.0) / strongSelf.bounds.width
            let currentScale = 1.0 * (1.0 - progress) + minScale * progress
            switch update {
            case .update:
                strongSelf.layer.sublayerTransform = CATransform3DMakeScale(currentScale, currentScale, 1.0)
            case .begin:
                strongSelf.layer.sublayerTransform = CATransform3DMakeScale(currentScale, currentScale, 1.0)
                /*let previousProgress: CGFloat = 0.0
                let previousScale = 1.0 * (1.0 - previousProgress) + minScale * previousProgress
                strongSelf.layer.sublayerTransform = CATransform3DMakeScale(currentScale, currentScale, 1.0)
                strongSelf.layer.animate(from: previousScale as NSNumber, to: currentScale as NSNumber, keyPath: "sublayerTransform.scale", timingFunction: kCAMediaTimingFunctionSpring, duration: 0.3, additive: false)*/
            case let .ended(previousProgress):
                let previousScale = 1.0 * (1.0 - previousProgress) + minScale * previousProgress
                strongSelf.layer.sublayerTransform = CATransform3DMakeScale(currentScale, currentScale, 1.0)
                strongSelf.layer.animate(from: previousScale as NSNumber, to: currentScale as NSNumber, keyPath: "sublayerTransform.scale", timingFunction: kCAMediaTimingFunctionSpring, duration: 0.3)
            }
        }
        contextGesture.activated = { [weak self] gesture in
            if let activated = self?.activated {
                activated(gesture)
            } else {
                gesture.cancel()
            }
        }
        contextGesture.isEnabled = self.isGestureEnabled
    }
}