KeyboardHackViewController.swift

//
//  ViewController.swift
//  KeyboardTransitionBug
//
//  Created by Sid on 07/12/2017.
//  Copyright © 2017 Picnic. All rights reserved.
//

import UIKit

class ViewController: UIViewController {

    @IBOutlet var imageView: UIImageView!
    @IBOutlet var searchField: SearchHeaderView!

    override func viewDidLoad() {
        super.viewDidLoad()
        NotificationCenter.default.addObserver(self, selector: #selector(onShowingKeyboard(notif:)), name: Notification.Name.UIKeyboardWillShow, object: nil)
    }

    @objc func onShowingKeyboard(notif: Notification) {
        addAndAnimate(parentView: imageView, info: notif.userInfo)
    }

    @IBAction func onTap() {
        addAndAnimate(parentView: imageView, info: nil)
    }

    func addAndAnimate(parentView: UIView, info: [AnyHashable : Any]?) {
        let (containerView, contentView, frame, constraints) = add(parentView: parentView)
        DispatchQueue.main.async { [weak self] in
            self?.animate(containerView: containerView, contentView: contentView, frame: frame, constraints: constraints, info: info)
        }
    }

    func add(parentView: UIView) -> (UIView?, UIView, CGRect, [NSLayoutConstraint]) {
        let img = UIImageView(image: UIImage(named: "IMG_4389.JPG"))
        let coordinateSpace = UIScreen.main.fixedCoordinateSpace
        let frame = view.convert(parentView.frame, to: coordinateSpace)
        let superView = UIApplication.shared.keyWindow?.rootViewController?.view  //UIApplication.shared.keyWindow
        superView?.addSubview(img)
        img.translatesAutoresizingMaskIntoConstraints = false

        let constraints: [NSLayoutConstraint] = [
            NSLayoutConstraint(item: img, attribute: .left, relatedBy: .equal, toItem: superView, attribute: .left, multiplier: 1.0, constant: frame.origin.x),
            NSLayoutConstraint(item: img, attribute: .top, relatedBy: .equal, toItem: superView, attribute: .top, multiplier: 1.0, constant: frame.origin.y),
            NSLayoutConstraint(item: img, attribute: .width, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1.0, constant: frame.size.width),
            NSLayoutConstraint(item: img, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1.0, constant: frame.size.height)
        ]

        superView?.addConstraints(constraints)
        return (superView, img, frame, constraints)
    }

    func animate(containerView: UIView?, contentView: UIView, frame: CGRect, constraints: [NSLayoutConstraint], info: [AnyHashable : Any]?) {

        precondition(containerView != nil)
        precondition(contentView.superview != nil)
        precondition(contentView.superview == containerView)
        precondition(constraints.count == 4)

        let duration: Double = (info?[UIKeyboardAnimationDurationUserInfoKey] as? NSNumber)?.doubleValue ?? 3.0
        let animationCurveRawNSN = info?[UIKeyboardAnimationCurveUserInfoKey] as? NSNumber
        let animationCurveRaw = Int(animationCurveRawNSN?.uintValue ?? UIViewAnimationOptions.curveEaseInOut.rawValue)
        let animationCurve = UIViewAnimationCurve(rawValue: animationCurveRaw) ?? UIViewAnimationCurve.easeOut

        let finalFrame = CGRect(x: frame.origin.x + 100, y: frame.origin.y - 100, width: 100, height: 100)

        print("\(frame) -> \(finalFrame)")

        containerView?.layoutIfNeeded()

        UIView.beginAnimations("animation-007", context: nil)
        UIView.setAnimationDuration(duration)
        UIView.setAnimationCurve(animationCurve)
        UIView.setAnimationBeginsFromCurrentState(true)
        constraints[0].constant = finalFrame.origin.x
        constraints[1].constant = finalFrame.origin.y
        constraints[2].constant = finalFrame.size.width
        constraints[3].constant = finalFrame.size.height
        containerView?.layoutIfNeeded()
        UIView.commitAnimations()


//        UIView.animate(withDuration: 3.0, delay: 0.0, options: [], animations: { [weak containerView] in
//            constraints[0].constant = finalFrame.origin.x
//            constraints[1].constant = finalFrame.origin.y
//            constraints[2].constant = finalFrame.size.width
//            constraints[3].constant = finalFrame.size.height
//            containerView?.layoutIfNeeded()
//            }, completion: { [weak contentView] complete in
//                assert(complete)
//                contentView?.removeFromSuperview()
//        })
    }

    @IBAction func onDismiss() {
        searchField.dismissKeyboard()
    }
}

final class SearchHeaderView: UIView {

    /// The title for the toggle button
    var toggleButtonTitle: String? {
        get {
            return toggleButton.title(for: .normal)
        }
        set {
            toggleButton.setTitle(newValue, for: .normal)
        }
    }

    /// The image for the toggle button
    var toggleButtonImage: UIImage? {
        get {
            return toggleButton.image(for: .normal)
        }
        set {
            toggleButton.setImage(newValue, for: .normal)
        }
    }

    // MARK: - UI Elements
    private let searchBar = UISearchBar()
    private let toggleButton = UIButton()

    init(barcodeScannerEnabled: Bool) {
        super.init(frame: .zero)
        setUp(displayBarcodeScannerButton: barcodeScannerEnabled)
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        setUp(displayBarcodeScannerButton: false)
    }

    override init(frame: CGRect) {
        super.init(frame: frame)
        setUp(displayBarcodeScannerButton: false)
    }

    private func setUp(displayBarcodeScannerButton: Bool) {
        /* Set the color of search bar background */
        // switch searchBarStyle
        //    case .Prominent:  inner view is automatically set to white, with a default 1px black border
        //    case .Minimal:  inner view is automatically set to some darker shade of background color
        let searchBackgroundColor = UIColor.lightGray
        /* color for elements within search bar like: text, input flashing indicator */

        backgroundColor = searchBackgroundColor

        /* add search bar */
        addSubview(searchBar)

        /* configure search bar */
        searchBar.searchBarStyle = .prominent
        searchBar.isTranslucent = false

        searchBar.barTintColor = searchBackgroundColor
        searchBar.tintColor = UIColor.red

        searchBar.autocapitalizationType = .none
        searchBar.backgroundImage = UIImage() // get rid of 1px black line

        /* add button */
        if displayBarcodeScannerButton {
            addSubview(toggleButton)

            /* configure button */
            toggleButton.setTitleColor(UIColor.red, for: .normal)
            toggleButton.titleLabel?.font = UIFont.preferredFont(forTextStyle: .body)
        }

        /* add constraints */
        searchBar.translatesAutoresizingMaskIntoConstraints = false
        addConstraints([
            NSLayoutConstraint(item: searchBar, attribute: .leading, relatedBy: .equal, toItem: self, attribute: .leading, multiplier: 1.0, constant: 8.0),
            NSLayoutConstraint(item: searchBar, attribute: .top, relatedBy: .equal, toItem: self, attribute: .top, multiplier: 1.0, constant: 8.0),
            NSLayoutConstraint(item: self, attribute: .bottom, relatedBy: .equal, toItem: searchBar, attribute: .bottom, multiplier: 1.0, constant: 8.0),
            ])

        if displayBarcodeScannerButton {
            toggleButton.translatesAutoresizingMaskIntoConstraints = false
            addConstraints([
                NSLayoutConstraint(item: toggleButton, attribute: .trailing, relatedBy: .equal, toItem: self, attribute: .trailing, multiplier: 1.0, constant: -16.0),
                NSLayoutConstraint(item: toggleButton, attribute: .centerY, relatedBy: .equal, toItem: searchBar, attribute: .centerY, multiplier: 1.0, constant: 0.0),
                NSLayoutConstraint(item: toggleButton, attribute: .leading, relatedBy: .equal, toItem: searchBar, attribute: .trailing, multiplier: 1.0, constant: 8.0)
                ])
        } else {
            addConstraints([
                NSLayoutConstraint(item: self, attribute: .trailing, relatedBy: .equal, toItem: searchBar, attribute: .trailing, multiplier: 1.0, constant: 8.0),
                ])
        }

        isAccessibilityElement = false
    }

    func presentKeyboard() {
        searchBar.becomeFirstResponder()
    }

    func dismissKeyboard() {
        searchBar.resignFirstResponder()
    }

    func setQuery(query: String) {
        searchBar.text = query
    }
}