//
//  HostingConfiguration.swift
//  ReviewsUIKit
//
//  Created by Javier Cicchelli on 18/03/2024.
//  Copyright © 2024 Röck+Cöde. All rights reserved.
//

import SwiftUI

public struct HostingConfiguration<Content: View>: UIContentConfiguration {
    
    // MARK: Type aliases
    public typealias ContentClosure = () -> Content
    
    // MARK: Constants
    fileprivate let hostingController: UIHostingController<Content>
    
    // MARK: Initialisers
    public init(@ViewBuilder content: ContentClosure) {
        hostingController = UIHostingController(rootView: content())
    }
    
    // MARK: Functions
    public func makeContentView() -> UIView & UIContentView {
        ContentView<Content>(self)
    }
    
    public func updated(
        for state: UIConfigurationState
    ) -> HostingConfiguration<Content> {
        self
    }
    
}

// MARK: - Classes
class ContentView<Content: View>: UIView, UIContentView {
    
    // MARK: Properties
    var configuration: UIContentConfiguration {
        didSet {
            configure(configuration)
        }
    }
    
    // MARK: Initialisers
    init(_ configuration: UIContentConfiguration) {
        self.configuration = configuration
        
        super.init(frame: .zero)
    }
    
    required init?(coder: NSCoder) {
        // This view shouldn't be initialized this way so we crash
        fatalError("init(coder:) has not been implemented")
    }
    
}

// MARK: - Helpers
private extension ContentView {
    
    // MARK: Functions
    func configure(_ configuration: UIContentConfiguration) {
        guard
            let configuration = configuration as? HostingConfiguration<Content>,
            let parent = findNextViewController()
        else {
            return
        }
        
        let hostingController = configuration.hostingController
        
        guard 
            let swiftUICellView = hostingController.view,
            subviews.isEmpty
        else {
            hostingController.view.invalidateIntrinsicContentSize()
            return
        }
        
        hostingController.view.backgroundColor = .clear
        
        parent.addChild(hostingController)
        addSubview(hostingController.view)
        
        hostingController.view.translatesAutoresizingMaskIntoConstraints = false

        NSLayoutConstraint.activate([
            leadingAnchor.constraint(equalTo: swiftUICellView.leadingAnchor),
            trailingAnchor.constraint(equalTo: swiftUICellView.trailingAnchor),
            topAnchor.constraint(equalTo: swiftUICellView.topAnchor),
            bottomAnchor.constraint(equalTo: swiftUICellView.bottomAnchor)
        ])
        
        hostingController.didMove(toParent: parent)
    }
    
}