vds_ios/VDS/Protocols/ViewProtocol.swift

//
//  ViewProtocol.swift
//  VDS
//
//  Created by Matt Bruce on 7/22/22.
//

import Foundation
import UIKit
import Combine

public protocol ViewProtocol: AnyObject, Initable, Resettable, Enabling, Surfaceable {
    /// Set of Subscribers for any Publishers for this Control.
    var subscribers: Set<AnyCancellable> { get set }
    
    /// Key of whether or not updateView() is called in setNeedsUpdate()
    var shouldUpdateView: Bool { get set }

    /// Key of whether or not updateAccessibility() is called in setNeedsUpdate()
    var shouldUpdateAccessibility: Bool { get set }

    /// Used for setting an implementation for the default Accessible Action
    var accessibilityAction: ((Self) -> Void)? { get set }

    /// Executed on initialization for this View.
    func initialSetup()
    
    /// Called once when a view is initialized and is used to Setup additional UI or other constants and configurations.
    func setup()
    
    /// Used to make changes to the View based off a change events or from local properties.
    func updateView()
    
    /// Used to update any Accessibility properties.
    func updateAccessibility()
}

extension ViewProtocol {
    
    /// Called when there are changes in a View based off a change events or from local properties.
    public func setNeedsUpdate() {
        if shouldUpdateView {
            shouldUpdateView = false
            updateView()
            if shouldUpdateAccessibility {
                updateAccessibility()
            }
            shouldUpdateView = true
        }
    }
}

extension ViewProtocol where Self: UIView {

    /// Helper method for removing a superview and updating Self.
    public func removeFromSuperview(_ view: UIView){
        if view.superview != nil {
            view.removeFromSuperview()
            setNeedsDisplay()
        }
    }    
}

extension ViewProtocol where Self: UIControl {
    /// Helper method to assign a completion block to a specific UIControl Event using Combine and stored in the subscribers.
    public func addEvent(event: UIControl.Event, block: @escaping (Self)->()) {
        publisher(for: event)
            .sink(receiveValue: { c in
                block(c)
            }).store(in: &subscribers)
    }
}

public protocol AccessibilityUpdatable {
    // Basic accessibility
    var bridge_isAccessibilityElementBlock: AXBoolReturnBlock? { get set }

    var bridge_accessibilityLabelBlock: AXStringReturnBlock? { get set }

    var bridge_accessibilityValueBlock: AXStringReturnBlock? { get set }

    var bridge_accessibilityHintBlock: AXStringReturnBlock? { get set }

    var bridge_accessibilityActivateBlock: AXBoolReturnBlock? { get set }

}

extension NSObject: AccessibilityUpdatable {
    static var isAccessibilityElementBlockKey: UInt8 = 0
    static var activateBlockKey: UInt8 = 1
    static var valueBlockKey: UInt8 = 2
    static var hintBlockKey: UInt8 = 3
    static var labelBlockKey: UInt8 = 4
    
    public var bridge_isAccessibilityElementBlock: AXBoolReturnBlock? {
        get {
            return objc_getAssociatedObject(self, &NSObject.isAccessibilityElementBlockKey) as? AXBoolReturnBlock
        }
        set {
            objc_setAssociatedObject(self, &NSObject.isAccessibilityElementBlockKey, newValue, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
//            if #available(iOS 17, *) {
//                self.isAccessibilityElementBlock = newValue
//            }
        }
    }
    
    public var bridge_accessibilityActivateBlock: AXBoolReturnBlock? {
        get {
            return objc_getAssociatedObject(self, &NSObject.activateBlockKey) as? AXBoolReturnBlock
        }
        set {
            objc_setAssociatedObject(self, &NSObject.activateBlockKey, newValue, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
//            if #available(iOS 17, *) {
//                self.accessibilityActivateBlock = newValue
//            }
        }
    }

    public var bridge_accessibilityValueBlock: AXStringReturnBlock? {
        get {
            return objc_getAssociatedObject(self, &NSObject.valueBlockKey) as? AXStringReturnBlock
        }
        set {
            objc_setAssociatedObject(self, &NSObject.valueBlockKey, newValue, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
//            if #available(iOS 17, *) {
//                self.accessibilityValueBlock = newValue
//            }
        }
    }

    public var bridge_accessibilityHintBlock: AXStringReturnBlock? {
        get {
            return objc_getAssociatedObject(self, &NSObject.hintBlockKey) as? AXStringReturnBlock
        }
        set {
            objc_setAssociatedObject(self, &NSObject.hintBlockKey, newValue, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
//            if #available(iOS 17, *) {
//                self.accessibilityHintBlock = newValue
//            }
        }
    }

    public var bridge_accessibilityLabelBlock: AXStringReturnBlock? {
        get {
            return objc_getAssociatedObject(self, &NSObject.labelBlockKey) as? AXStringReturnBlock
        }
        set {
            objc_setAssociatedObject(self, &NSObject.labelBlockKey, newValue, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
//            if #available(iOS 17, *) {
//                self.accessibilityLabelBlock = newValue
//            }
        }
    }
    
}