//
//  CommonControllerAutocomplete.swift
//  Wallet
//
//  Created by Igor on 10.02.2021.
//

import UIKit
import Combine
import WalletUIComponents

class CommonControllerAutocomplete: UIViewController {
    
    @IBOutlet private weak var tableView: UITableView!
    @IBOutlet private weak var searchTextFieldContainer: UIView!
    @IBOutlet private weak var height: NSLayoutConstraint!
    
    private let viewModel: TextFieldViewModel
    private var cancellables = Set<AnyCancellable>()
    
    private let completion: (Common.Model.Menu) -> Void
    private let service: CommonMenuAutocompleteService
    private var collection = [Common.Model.Menu]()
    private var isLoading = false
    private var selected: Common.Model.Menu?
    
    init(
        image: UIImage? = nil,
        title: String? = nil,
        text: String? = nil,
        placeholder: String? = nil,
        service: CommonMenuAutocompleteService,
        selected: Common.Model.Menu? = nil,
        _ completion: @escaping (Common.Model.Menu) -> Void
    ) {
        self.service = service
        self.selected = selected
        self.completion = completion
        self.viewModel = TextFieldViewModel(placeholder: placeholder ?? "")
        
        super.init(nibName: "CommonControllerAutocomplete", bundle: nil)
        
        self.title = title
        self.text = text
        self.image = image
        _ = view
        self.height.constant = 2*UIScreen.main.bounds.height/3
        self.view.layoutIfNeeded()
        
        self.tableView.register(cell: CommonCellAutocomplete.self)
        self.service.didUpdate = {
            Loader.hide(in: self.tableView)
            self.collection = service.collection
            self.isLoading = false
            self.tableView.reloadData()
        }
        self.reload()
    }
    
    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        self.setupTextFieldSearch()
    }
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        
        self.viewModel.objectWillChange
            .receive(on: DispatchQueue.main)
            .sink { [weak self] in
                guard let self else { return }
                self.textFieldDidChange(self.viewModel.text)
            }
            .store(in: &self.cancellables)
    }
    
    private func reload() {
        self.isLoading = true
        self.tableView.reloadData()
        if !Loader.isLoading(in: self.tableView) {
            Loader.show(in: self.tableView)
        }
        self.service.apply(filter: self.viewModel.text)
    }
    
    private func setupTextFieldSearch() {
        let textField = CommonTextFieldSearch(viewModel: self.viewModel)
        let hostingTextFieldView = UIHostingView(rootView: textField, autoresizingMask: false)
        self.searchTextFieldContainer.addSubview(hostingTextFieldView)
        
        NSLayoutConstraint.activate([
            hostingTextFieldView.topAnchor.constraint(equalTo: self.searchTextFieldContainer.topAnchor),
            hostingTextFieldView.leadingAnchor.constraint(equalTo: self.searchTextFieldContainer.leadingAnchor),
            hostingTextFieldView.trailingAnchor.constraint(equalTo: self.searchTextFieldContainer.trailingAnchor),
            hostingTextFieldView.bottomAnchor.constraint(equalTo: self.searchTextFieldContainer.bottomAnchor)
        ])
    }
    
    private func textFieldDidChange(_ text: String?) {
        self.reload()
    }
}

extension CommonControllerAutocomplete: UITableViewDataSource, UITableViewDelegate {
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int { self.isLoading ? 0 : self.collection.count }
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(CommonCellAutocomplete.self, indexPath: indexPath)
        cell.adjust(to: self.collection[indexPath.row], isSelected: self.selected == self.collection[indexPath.row])
        return cell
    }
    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        self.selected = collection[indexPath.row]
        tableView.reloadData()
        self.dismiss(animated: true) { self.completion(self.collection[indexPath.row]) }
    }
}