//
//  RadioButtonGroup.swift
//  VDS
//
//  Created by Matt Bruce on 8/8/22.
//

import Foundation
import UIKit


public protocol SelectorGroupModel<SelectorType>: Modelable, FormFieldable {
    associatedtype SelectorType: SelectorModel
    var selectors: [SelectorType] { get set }
}

public struct DefaultSelectorGroupModel<SelectorType: SelectorModel>: SelectorGroupModel {
    public var inputId: String?
    public var value: AnyHashable?
    public var surface: Surface = .light
    public var disabled: Bool = false
    public var selectors: [SelectorType]
    public init() { selectors = [] }
    public init(selectors: [SelectorType]){
        self.selectors = selectors
    }
}

open class SelectorGroup<SelectorType, SelectorGroupType: SelectorGroupModel<SelectorType>, SelectorHandlerType: SelectorBase<SelectorType>>: View<SelectorGroupType>, Changable {
    
    public var selectorViews: [SelectorHandlerType] = []
    public var selectedModel: SelectorType?
    public var onChange: Blocks.ActionBlock?

    //--------------------------------------------------
    // MARK: - Private Properties
    //--------------------------------------------------
    private var mainStackView: UIStackView = {
       let stackView = UIStackView()
        stackView.translatesAutoresizingMaskIntoConstraints = false
        stackView.alignment = .top
        stackView.axis = .vertical
        stackView.spacing = 10
        return stackView
    }()

    //--------------------------------------------------
    // MARK: - Overrides
    //--------------------------------------------------
    override public var disabled: Bool {
        didSet {
            let selectors = model.selectors.compactMap { existing in
                return updated(existing){
                    $0.disabled = disabled
                }
            }
            model.selectors = selectors
        }
    }

    override public var surface: Surface {
        didSet {
            let selectors = model.selectors.compactMap { existing in
                return updated(existing){
                    $0.surface = surface
                }
            }
            model.selectors = selectors
        }
    }

    open override func setup() {
        super.setup()

        isAccessibilityElement = true
        accessibilityTraits = .button
        addSubview(mainStackView)

        mainStackView.topAnchor.constraint(equalTo: topAnchor).isActive = true
        mainStackView.leadingAnchor.constraint(equalTo: leadingAnchor).isActive = true
        mainStackView.trailingAnchor.constraint(equalTo: trailingAnchor).isActive = true
        mainStackView.bottomAnchor.constraint(equalTo: bottomAnchor).isActive = true
    }

    open override func shouldUpdateView(viewModel: ModelType) -> Bool {
        return true
    }

    open override func updateView(viewModel: ModelType) {
        print("Selector Group update:")
        func findSelectorView(inputId: String) -> SelectorHandlerType? {
            return selectorViews.first(where: { existingSelectorView in
                return existingSelectorView.model.inputId == inputId 
            })
        }
        
        for selectorModel in viewModel.selectors {
            //see if view is there for the model
            if let inputId = selectorModel.inputId, let foundSelectorView = findSelectorView(inputId: inputId) {
                foundSelectorView.set(with: selectorModel)
            } else {
                //create view
                let newSelectorView = SelectorHandlerType(with: selectorModel)
                newSelectorView.didSelect = {[weak self] (inputId) in
                    guard let self else { return }
                    self.didSelect(selected: selectorModel)
                }
                self.selectorViews.append(newSelectorView)
                mainStackView.addArrangedSubview(newSelectorView)
            }
        }
        
    }
    
    open func didSelect(selected: SelectorType) { }
}