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

import Foundation
import UIKit
import Combine

/// Base Class use to build Controls.
@objc(VDSControl)
open class Control: UIControl, ViewProtocol, UserInfoable, Clickable {
    //--------------------------------------------------
    // MARK: - Initializers
    //--------------------------------------------------
    required public init() {
        super.init(frame: .zero)
        initialSetup()
    }
    
    public override init(frame: CGRect) {
        super.init(frame: .zero)
        initialSetup()
    }
    
    public required init?(coder: NSCoder) {
        super.init(coder: coder)
        initialSetup()
    }
    
    //--------------------------------------------------
    // MARK: - Combine Properties
    //--------------------------------------------------
    open var subscribers = Set<AnyCancellable>()

    open var onClickSubscriber: AnyCancellable? 
        
    //--------------------------------------------------
    // MARK: - Private Properties
    //--------------------------------------------------
    private var initialSetupPerformed = false
    
    //--------------------------------------------------
    // MARK: - Public Properties
    //--------------------------------------------------
    open var shouldUpdateView: Bool = true
    
    open var shouldUpdateAccessibility: Bool = true
    
    open var userInfo = [String: Primitive]()
    
    open var surface: Surface = .light { didSet { setNeedsUpdate() } }
    
    /// Whether the Control is selected or not.
    open override var isSelected: Bool { didSet { setNeedsUpdate() } }

    /// State of animating isHighlight.
    public var isHighlighting = false
    
    /// Whether the Control should handle the isHighlighted state.
    open var shouldHighlight: Bool { isHighlighting == false && onClickSubscriber != nil }
    
    /// Whether the Control is highlighted or not.
    open override var isHighlighted: Bool {
        didSet {
            if shouldHighlight {
                isHighlighting = true
                setNeedsUpdate()
                isHighlighting = false
            }
        }
    }
    
    /// Whether the Control is enabled or not.
    open override var isEnabled: Bool { didSet { setNeedsUpdate() } }

    //--------------------------------------------------
    // MARK: - Lifecycle
    //--------------------------------------------------
    open func initialSetup() {
        if !initialSetupPerformed {
            initialSetupPerformed = true
            setup()
            setNeedsUpdate()
        }
    }
    
    open func setup() {
        backgroundColor = .clear
        translatesAutoresizingMaskIntoConstraints = false
        insetsLayoutMarginsFromSafeArea = false
    }
            
    open func updateView() { }
    
    open func updateAccessibility() {
        if isSelected {
            accessibilityTraits.insert(.selected)
        } else {
            accessibilityTraits.remove(.selected)
        }
        
        if isEnabled {
            accessibilityTraits.remove(.notEnabled)
        } else {
            accessibilityTraits.insert(.notEnabled)
        }

    }
    
    open func reset() {
        backgroundColor = .clear
        surface = .light
        isEnabled = true
        onClick = nil
        userInfo.removeAll()
    }
    
    //--------------------------------------------------
    // MARK: - Overrides
    //--------------------------------------------------
    /// Implement accessibilityActivate on an element in order to handle the default action.
    /// - Returns: Based on whether the userInteraction is enabled.
    override open func accessibilityActivate() -> Bool {
        // Hold state in case User wanted isAnimated to remain off.
        guard isUserInteractionEnabled else { return false }
        sendActions(for: .touchUpInside)
        return true
    }

    open override func layoutSubviews() {
        super.layoutSubviews()
        setNeedsUpdate()
    }
}