//
//  CommonKeyboard.swift
//  Wallet
//
//  Created by Igor on 23.03.2021.
//  Copyright © 2021 AM. All rights reserved.
//

import UIKit

public struct KeyboardInfo {
    public let frameBegin: CGRect
    public let frameEnd: CGRect
    public let isLocal: Bool
    public let animationCurve: Int
    public let duration: TimeInterval
}

public extension KeyboardInfo {
    init(notification: Notification) {
        frameBegin = (notification.userInfo?[UIResponder.keyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue ?? CGRect.zero
        frameEnd = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue ?? CGRect.zero
        isLocal = (notification.userInfo?[UIResponder.keyboardIsLocalUserInfoKey] as? Bool) ?? true
        animationCurve = (notification.userInfo?[UIResponder.keyboardAnimationCurveUserInfoKey] as? Int) ?? 0
        duration = (notification.userInfo?[UIResponder.keyboardAnimationDurationUserInfoKey] as? TimeInterval) ?? 0
    }
}

enum KeyboardConnectionType: String {
    case willShow
    case didShow
    case willHide
    case didHide
    case willChangeFrame
    case didChangeFrame
    fileprivate var notification: NSNotification.Name {
        ([
            .willShow: UIResponder.keyboardWillShowNotification,
            .didShow: UIResponder.keyboardDidShowNotification,
            .willHide: UIResponder.keyboardWillHideNotification,
            .didHide: UIResponder.keyboardDidHideNotification,
            .willChangeFrame: UIResponder.keyboardWillChangeFrameNotification,
            .didChangeFrame: UIResponder.keyboardDidChangeFrameNotification
        ] as [KeyboardConnectionType: NSNotification.Name])[self]!
    }
}

extension UIViewController {
    private struct Keyboard {
        static var values = "values"
    }
    private var keyboard: [KeyboardConnectionType: AnyObject]? {
        get { Common.Runtime.object(self, key: &Keyboard.values) }
        set { Common.Runtime.set(self, value: newValue, key: &Keyboard.values) }
    }
    func connectKeyboard(action: KeyboardConnectionType, _ handler: ((KeyboardInfo) -> Void)?) {
        let value = Notification.subscribe(name: action.notification) { (ntf) in
            handler?(KeyboardInfo(notification: ntf))
        }
        if keyboard == nil {
            keyboard = [action: value]
        } else {
            keyboard?[action] = value
        }
    }
    func disconnectKeyboard() {
        disconnectKeyboard(action: .willShow)
        disconnectKeyboard(action: .willHide)
        disconnectKeyboard(action: .didShow)
        disconnectKeyboard(action: .didHide)
        disconnectKeyboard(action: .willChangeFrame)
        disconnectKeyboard(action: .didChangeFrame)
    }
    func disconnectKeyboard(action: KeyboardConnectionType) {
        guard let object = keyboard?[action] else { return }
        Notification.unsubscribe(observer: object)
        keyboard?.removeValue(forKey: action)
    }
    
    var appDelegate: AppDelegate {
        // swiftlint:disable force_cast
        return UIApplication.shared.delegate as! AppDelegate
    }
}