//
//  CollectionViewCell.swift
//  VDS
//
//  Created by Matt Bruce on 8/25/22.
//

import Foundation
import UIKit
import Combine

open class CollectionViewCell<ModelHandlerType: ModelHandlerable & UIView>: UICollectionViewCell, ModelHandlerable, ViewProtocol, Resettable {
    public typealias ModelType = ModelHandlerType.ModelType
    //--------------------------------------------------
    // MARK: - Combine Properties
    //--------------------------------------------------
    @Published public var model: ModelType = ModelType()
    public var modelPublisher: Published<ModelType>.Publisher { $model }
    public var subscribers = Set<AnyCancellable>()
    
    //--------------------------------------------------
    // MARK: - Properties
    //--------------------------------------------------
    private var initialSetupPerformed = false

    public var modelHandler: ModelHandlerType = ModelHandlerType()

    @Proxy(\.model.surface)
    open var surface: Surface
    
    @Proxy(\.model.disabled)
    open var disabled: Bool {
        didSet {
            self.isEnabled = !disabled
        }
    }
    
    open var isEnabled: Bool {
        get { !model.disabled }
        set {
            //create local vars for clear coding
            let disabled = !newValue
            if model.disabled != disabled {
                model.disabled = disabled
            }
        }
    }
    
    //--------------------------------------------------
    // MARK: - Initializers
    //--------------------------------------------------
    required public init() {
        super.init(frame: .zero)
        initialSetup()
    }
    
    public required init(with model: ModelType) {
        super.init(frame: .zero)
        initialSetup()
        set(with: model)
    }
    
    public override init(frame: CGRect) {
        super.init(frame: frame)
        initialSetup()
        set(with: model)
    }

    public required init?(coder: NSCoder) {
        super.init(coder: coder)
        initialSetup()
    }
    
    //--------------------------------------------------
    // MARK: - Setup
    //--------------------------------------------------
    
    public func initialSetup() {
        if !initialSetupPerformed {
            initialSetupPerformed = true
            setupUpdateView()
            setup()
        }
    }
    
    //--------------------------------------------------
    // MARK: - Overrides
    //--------------------------------------------------
    open func shouldUpdateView(viewModel: ModelType) -> Bool {
        return modelHandler.shouldUpdateView(viewModel: viewModel)
    }
    
    open func updateView(viewModel: ModelType) {
        modelHandler.updateView(viewModel: viewModel)
    }
        
    open func reset() {
        backgroundColor = .clear
        if let model = model as? Resettable {
            model.reset()
        }
    }
    
    public func set(with model: ModelType) {
        self.model = model
        modelHandler.set(with: model)
    }
    
    // MARK: - ViewProtocol
    /// Will be called only once.
    open func setup() {
        translatesAutoresizingMaskIntoConstraints = false
        insetsLayoutMarginsFromSafeArea = false
        
        addSubview(modelHandler)
        
        modelHandler.topAnchor.constraint(equalTo: topAnchor).isActive = true
        modelHandler.leadingAnchor.constraint(equalTo: leadingAnchor).isActive = true
        modelHandler.trailingAnchor.constraint(equalTo: trailingAnchor).isActive = true
        modelHandler.bottomAnchor.constraint(equalTo: bottomAnchor).isActive = true
    }
}