import Foundation
import UIKit
import AsyncDisplayKit
import SwiftSignalKit

public func addAccessibilityChildren(of node: ASDisplayNode, container: Any, to list: inout [Any]) {
    if node.isAccessibilityElement {
        let element = UIAccessibilityElement(accessibilityContainer: container)
        element.accessibilityFrame = UIAccessibility.convertToScreenCoordinates(node.bounds, in: node.view)
        element.accessibilityLabel = node.accessibilityLabel
        element.accessibilityValue = node.accessibilityValue
        element.accessibilityTraits = node.accessibilityTraits
        element.accessibilityHint = node.accessibilityHint
        element.accessibilityIdentifier = node.accessibilityIdentifier
        
        //node.accessibilityFrame = UIAccessibilityConvertFrameToScreenCoordinates(node.bounds, node.view)
        list.append(element)
    } else if let accessibilityElements = node.accessibilityElements {
        list.append(contentsOf: accessibilityElements)
    }
}

public func smartInvertColorsEnabled() -> Bool {
    if #available(iOSApplicationExtension 11.0, iOS 11.0, *), UIAccessibility.isInvertColorsEnabled {
        return true
    } else {
        return false
    }
}

public func isReduceMotionEnabled() -> Signal<Bool, NoError> {
    return Signal { subscriber in
        subscriber.putNext(UIAccessibility.isReduceMotionEnabled)
        
        let observer = NotificationCenter.default.addObserver(forName: UIAccessibility.reduceMotionStatusDidChangeNotification, object: nil, queue: .main, using: { _ in
            subscriber.putNext(UIAccessibility.isReduceMotionEnabled)
        })
        
        return ActionDisposable {
            Queue.mainQueue().async {
                NotificationCenter.default.removeObserver(observer)
            }
        }
    } |> runOn(Queue.mainQueue())
}

public func isSpeakSelectionEnabled() -> Bool {
    return UIAccessibility.isSpeakSelectionEnabled
}

public func isSpeakSelectionEnabledSignal() -> Signal<Bool, NoError> {
    return Signal { subscriber in
        subscriber.putNext(UIAccessibility.isSpeakSelectionEnabled)
        
        let observer = NotificationCenter.default.addObserver(forName: UIAccessibility.speakSelectionStatusDidChangeNotification, object: nil, queue: .main, using: { _ in
            subscriber.putNext(UIAccessibility.isSpeakSelectionEnabled)
        })
        
        return ActionDisposable {
            Queue.mainQueue().async {
                NotificationCenter.default.removeObserver(observer)
            }
        }
    } |> runOn(Queue.mainQueue())
}

public func isBoldTextEnabled() -> Signal<Bool, NoError> {
    return Signal { subscriber in
        subscriber.putNext(UIAccessibility.isBoldTextEnabled)
        
        let observer = NotificationCenter.default.addObserver(forName: UIAccessibility.boldTextStatusDidChangeNotification, object: nil, queue: .main, using: { _ in
            subscriber.putNext(UIAccessibility.isBoldTextEnabled)
        })
        
        return ActionDisposable {
            Queue.mainQueue().async {
                NotificationCenter.default.removeObserver(observer)
            }
        }
    }
    |> runOn(Queue.mainQueue())
}

public func isReduceTransparencyEnabled() -> Bool {
    UIAccessibility.isReduceTransparencyEnabled
}