vds_ios/VDS/BaseClasses/Selector/SelectorBase.swift

//
//  SelectorBase.swift
//  VDS
//
//  Created by Matt Bruce on 6/5/23.
//

import Foundation
import UIKit
import Combine
import VDSCoreTokens

public protocol SelectorControlable: Control, Changeable {
    /// Whether not to show the error.
    var showError: Bool { get set }
    
    /// Size of the SelectorView.
    var size: CGSize { get set }
    
    /// Configuration for the Background Color based on Control State.
    var backgroundColorConfiguration: ControlColorConfiguration { get set }

    /// Configuration for the Border Color based on Control State.
    var borderColorConfiguration: ControlColorConfiguration { get set }

    /// Configuration for the Selector Color based on Control State.
    var selectorColorConfiguration: ControlColorConfiguration { get set }
}

/// Base Class used to build out a Selector control.
open class SelectorBase: Control, SelectorControlable {
    //--------------------------------------------------
    // MARK: - Initializers
    //--------------------------------------------------
    required public init() {
        super.init(frame: .zero)
    }
    
    public override init(frame: CGRect) {
        super.init(frame: .zero)
    }
    
    public required init?(coder: NSCoder) {
        super.init(coder: coder)
    }
    
    //--------------------------------------------------
    // MARK: - Public Properties
    //--------------------------------------------------
    open var onChangeSubscriber: AnyCancellable?
    
    open var size = CGSize(width: 20, height: 20) { didSet { setNeedsUpdate() } }
    
    var _showError: Bool = false
    /// Whether not to show the error.
    open var showError: Bool {
        get { _showError }
        set {
            if !isSelected && _showError != newValue {
                _showError = newValue
                setNeedsUpdate()
            }
        }
    }
    
    /// Override UIControl state to add the .error state if showError is true.
    open override var state: UIControl.State {
        get {
            var state = super.state
            if showError {
                state.insert(.error)
            } else {
                state.remove(.error)
            }
            return state
        }
    }
    
    open var backgroundColorConfiguration = ControlColorConfiguration() { didSet { setNeedsUpdate() } }
    
    open var borderColorConfiguration = ControlColorConfiguration() { didSet { setNeedsUpdate() } }
    
    open var selectorColorConfiguration = ControlColorConfiguration() { didSet { setNeedsUpdate() } }
    
    /// The natural size for the receiving view, considering only properties of the view itself.
    open override var intrinsicContentSize: CGSize { size }

    //--------------------------------------------------
    // MARK: - Private Properties
    //--------------------------------------------------
    private var selectorView = View()
    
    //--------------------------------------------------
    // MARK: - Constraints
    //--------------------------------------------------
    internal var shapeLayer: CAShapeLayer?
       
    //--------------------------------------------------
    // MARK: - Overrides
    //--------------------------------------------------
    /// Executed on initialization for this View.
    open override func initialSetup() {
        super.initialSetup()
        onClick = { control in
            control.toggle()
        }
    }
    
    /// Called once when a view is initialized and is used to Setup additional UI or other constants and configurations.
    open override func setup() {
        super.setup()
        
        isAccessibilityElement = true
        accessibilityTraits = .button
    }
    
    open override func updateView() {
        super.updateView()
        setNeedsLayout()
        layoutIfNeeded()
    }

    /// Used to update any Accessibility properties.ß
    open override func updateAccessibility() {
        super.updateAccessibility()
        accessibilityLabel = "\(Self.self)\(showError ? ", error" : "")"
        accessibilityHint = !isEnabled ? "" : "Double tap to open."
    }
    
    /// This will change the state of the Selector and execute the actionBlock if provided.
    open func toggle() { }

    open override func reset() {
        super.reset()
        onChange = nil 
    }
}