//
//  ModelViewController.swift
//  VDSSample
//
//  Created by Matt Bruce on 8/15/22.
//

import Foundation
import UIKit
import Combine
import VDS

public class ModelScrollViewController: UIViewController, ModelHandlerable, Initable {
    deinit {
        print("\(Self.self) deinit")
    }
    
    private let edgeSpacing = 16.0
    private let topBottomSpacing = 20.0

    //--------------------------------------------------
    // MARK: - Combine Properties
    //--------------------------------------------------
    public var subject = PassthroughSubject<Void, Never>()
    public var subscribers = Set<AnyCancellable>()
    public var firstRender: Bool = false

    //--------------------------------------------------
    // MARK: - Properties
    //--------------------------------------------------
    private var initialSetupPerformed = false

    open var surface: Surface = .light { didSet { subject.send() }}
    
    open var disabled: Bool = false { didSet { subject.send() }}
    
    //--------------------------------------------------
    // MARK: - Initializers
    //--------------------------------------------------
    required public init() {
        super.init(nibName: nil, bundle: nil)
        initialSetup()
    }
        
    public override init(nibName nibNameOrNil: String?, bundle nibBundleOrNil: Bundle?) {
        super.init(nibName: nil, bundle: nil)
        initialSetup()
    }
    
    public required init?(coder: NSCoder) {
        super.init(coder: coder)
        initialSetup()
    }

    //--------------------------------------------------
    // MARK: - Setup
    //--------------------------------------------------
    
    public func initialSetup() {
        if !initialSetupPerformed {
            initialSetupPerformed = true
            setupUpdateView()
            setup()
            contentTopView.backgroundColor = Surface.light.color
            surfacePickerSelectorView.scrollToBottom = { [weak self] in self?.scrollToBottom()}
        }
    }
    
    public lazy var surfacePickerSelectorView = {
        SurfacePickerSelectorView(picker: self.picker)
    }()
    
    public var picker: UIPickerView = {
        return UIPickerView().with {
            $0.backgroundColor = .white
            $0.translatesAutoresizingMaskIntoConstraints = false
        }
    }()

    public var contentView: UIView = {
        return UIView().with {
            $0.translatesAutoresizingMaskIntoConstraints = false
        }
    }()
    
    public var formStackView: UIStackView = {
        return UIStackView().with {
            $0.translatesAutoresizingMaskIntoConstraints = false
            $0.alignment = .fill
            $0.distribution = .fillProportionally
            $0.axis = .vertical
            $0.spacing = 10
        }
    }()
    
    public var contentTopView: UIView = {
        return UIView().with {
            $0.translatesAutoresizingMaskIntoConstraints = false
        }
    }()

    public var contentBottomView: UIView = {
        return UIView().with {
            $0.translatesAutoresizingMaskIntoConstraints = false
        }
    }()

    open override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = .white
        
        embed(scrollViewController)
        scrollViewController.scrollView.alwaysBounceVertical = true
        scrollViewController.contentView = contentView
        contentView.addSubview(contentTopView)
        contentView.addSubview(contentBottomView)
        contentBottomView.addSubview(formStackView)
        
//        contentTopView.backgroundColor = .green
//        contentBottomView.backgroundColor = .yellow
        
        contentTopView.topAnchor.constraint(equalTo: contentView.topAnchor, constant: edgeSpacing).isActive = true
        contentTopView.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: edgeSpacing).isActive = true
        contentTopView.trailingAnchor.constraint(equalTo: contentView.trailingAnchor, constant: -edgeSpacing).isActive = true

        contentBottomView.topAnchor.constraint(equalTo: contentTopView.bottomAnchor, constant: edgeSpacing).isActive = true
        contentBottomView.leadingAnchor.constraint(equalTo: contentView.leadingAnchor, constant: edgeSpacing).isActive = true
        contentBottomView.trailingAnchor.constraint(equalTo: contentView.trailingAnchor, constant: -edgeSpacing).isActive = true
        contentBottomView.bottomAnchor.constraint(lessThanOrEqualTo: contentView.bottomAnchor, constant: -edgeSpacing).isActive = true
        
        formStackView.topAnchor.constraint(equalTo: contentBottomView.topAnchor, constant: edgeSpacing).isActive = true
        formStackView.leadingAnchor.constraint(equalTo: contentBottomView.leadingAnchor, constant: edgeSpacing).isActive = true
        formStackView.trailingAnchor.constraint(equalTo: contentBottomView.trailingAnchor, constant: -edgeSpacing).isActive = true
        formStackView.bottomAnchor.constraint(equalTo: contentBottomView.bottomAnchor, constant: -100).isActive = true

        view.addSubview(picker)
        picker.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor).isActive = true
        picker.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor).isActive = true
        picker.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor).isActive = true
        picker.isHidden = true
    }

    private let scrollViewController = ScrollViewController()

    public func scrollToBottom() {
        let bottomOffset = CGPoint(x: 0, y: scrollViewController.scrollView.contentSize.height - scrollViewController.scrollView.bounds.height + scrollViewController.scrollView.contentInset.bottom)
        scrollViewController.scrollView.setContentOffset(bottomOffset, animated: true)
    }
    
    private func embed(_ viewController: UIViewController) {
        addChild(viewController)
        view.addSubview(viewController.view)
        viewController.view.translatesAutoresizingMaskIntoConstraints = false
        viewController.view.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
        viewController.view.leadingAnchor.constraint(equalTo: view.leadingAnchor).isActive = true
        viewController.view.trailingAnchor.constraint(equalTo: view.trailingAnchor).isActive = true
        viewController.view.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true
        viewController.didMove(toParent: self)
    }
    
    open func addContentTopView(view: UIView) {
        contentTopView.addSubview(view)
        view.leadingAnchor.constraint(equalTo: contentTopView.leadingAnchor, constant: edgeSpacing).isActive = true
        view.topAnchor.constraint(equalTo: contentTopView.topAnchor, constant: topBottomSpacing).isActive = true

        view.trailingAnchor.constraint(lessThanOrEqualTo: contentTopView.trailingAnchor, constant: -edgeSpacing).isActive = true
        view.bottomAnchor.constraint(lessThanOrEqualTo: contentTopView.bottomAnchor, constant: -topBottomSpacing).isActive = true
    }

    open func addFormRow(label: String, view: UIView, stackView: UIStackView? = nil) {
        let formRow = UIStackView().with {
            $0.translatesAutoresizingMaskIntoConstraints = false
            $0.alignment = .fill
            $0.distribution = .fillEqually
            $0.axis = .horizontal
            $0.spacing = 5
        }
        
        let label = UILabel().with {
            $0.text = label
        }
        
        formRow.addArrangedSubview(label)
        formRow.addArrangedSubview(view)
        
        if let stackView  {
            stackView.addArrangedSubview(formRow)
        } else {
            formStackView.addArrangedSubview(formRow)
        }
        
        if let pickerViewable = view as? any PickerViewable {
            pickerViewable.scrollToBottom = { [weak self] in self?.scrollToBottom() }
        }
    }

    open func setup() {}
    
    open func updateView() {
        print("\(Self.self) updateView()")
    }

}