//
//  MainControllerContent.swift
//  List
//
//  Created by Igor Danich on 25.06.2020.
//  Copyright © 2020 Igor Danich. All rights reserved.
//

import UIKit
import class Resolver.Resolver
import struct RealmSwift.Results
import class RealmSwift.NotificationToken
import Combine
import WalletKit

final class MainControllerContent: UITabBarController {

    var update: (() -> Void)?

    deinit { bag.flush() }

    private var cancellables = Set<AnyCancellable>()
    
    private var deals: Results<P2PDeal> = Resolver.resolve()
    private var notificationTokens: [NotificationToken] = []

    private func setupP2PBadges() {
//        viewControllers?.first(where: { (($0 as? UINavigationController)?.viewControllers.first as? P2PControllerDashboard)?.service.kind == .buy })?.tabBarItem.badgeValue = "\(P2PMyDealsService.shared.allBuyDeals.count)"

        let activeDeals = deals.filter("didWithdraw == false || status IN {'proceed', 'dispute'}")
        let allBuyDealsCount = activeDeals.filter("buyer == '\(Accounts().current?.name ?? "")'").count
        let allSellDealsCount = activeDeals.filter("seller == '\(Accounts().current?.name ?? "")'").count

        if let viewControllers = self.viewControllers,
            let viewController = viewControllers[safe: 2] {
            viewController.tabBarItem.badgeValue = allSellDealsCount > 0 ? "\(allSellDealsCount)" : nil
        }
        
        if let viewControllers = self.viewControllers,
            let viewController = viewControllers[safe: 3] {
            viewController.tabBarItem.badgeValue = allBuyDealsCount > 0 ? "\(allBuyDealsCount)" : nil
        }
        
    }

    override func viewDidLoad() {
        
        super.viewDidLoad()
        
        self.setupTabBarOrder()
        
        Notification.subscribe(bag: bag, name: .didChangeInterface) { [weak self]_ in
            self?.setupTabBarOrder()
        }
        
        Accounts().activePublisher
            .receive(on: DispatchQueue.main)
            .sink { [weak self] wallet in
                
                guard let self else { return }
                
                self.notificationTokens.removeAll()
                self.deals = Resolver.resolve()
                self.notificationTokens.append(contentsOf: [
                    self.deals.observe { [weak self] _ in self?.setupP2PBadges() }
                ].compactMap { $0 })

                // Cryprocash exchange requests
                self.viewControllers?[4].tabBarItem.badgeValue = nil

                self.checkForAccountAvailability(wallet: wallet)
            }
            .store(in: &self.cancellables)

        Notification.subscribe(name: .didUpdateHistory) {
            guard Accounts().current?.name == $0.userInfo?["username"] as? String else { return }
        }
    }
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        if let currentVisibleNavController = self.viewControllers?[self.selectedIndex],
           let topVC = currentVisibleNavController.children.last {
            self.setupMainControllerPresentation(on: topVC)
        }
    }

    func push(_ viewController: UIViewController, animated: Bool) {
        guard let navigationController = selectedViewController as? UINavigationController,
              !(navigationController.topViewController?.isKind(of: type(of: viewController)) ?? true) else { return }

        (selectedViewController as? UINavigationController)?.pushViewController(viewController, animated: animated)
    }

    func pop(animated: Bool) {
        (selectedViewController as? UINavigationController)?.popViewController(animated: animated)
    }

    func popToRoot(animated: Bool) {
        (selectedViewController as? UINavigationController)?.popToRootViewController(animated: animated)
    }

    func setupTabBarOrder() {
        let viewControllers: [UIViewController]
        if UserDefaults.standard.bool(forKey: "chatsFirst") {
            viewControllers = [
                StoryboardScene.CryptoChat.initialScene.instantiate(),
                StoryboardScene.Wallet.initialScene.instantiate(),
//                StoryboardScene.Swap.swapNavigationMain.instantiate(),
                p2p(isSell: true),
                p2p(isSell: false),
                StoryboardScene.DeFi.deFiNavigationControllerMain.instantiate()
            ]
            self.selectedIndex = 0
        } else {
            viewControllers = [
                StoryboardScene.Wallet.initialScene.instantiate(),
                StoryboardScene.CryptoChat.initialScene.instantiate(),
//                StoryboardScene.Swap.swapNavigationMain.instantiate(),
                p2p(isSell: true),
                p2p(isSell: false),
                StoryboardScene.DeFi.deFiNavigationControllerMain.instantiate()
            ]
        }
//        viewControllers?
//            .compactMap({ $0 as? UINavigationController })
//            .compactMap({ $0.viewControllers.first })
//            .filter({ !($0 is CryptoChatControllerChats) })
//            .forEach({ print($0) })
//            .forEach({ _ = $0.view })
        viewControllers
            .compactMap { $0 as? UINavigationController }
            .forEach { $0.delegate = self }
        
        self.viewControllers = viewControllers
//        selectedIndex = 2
    }

    private func p2p(isSell: Bool) -> UIViewController {
        let ctrl = StoryboardScene.P2P.initial.instantiate()
        ctrl.service = P2P.Service.dashboard(kind: isSell ? .sell : .buy)
        let navCtrl = UINavigationController(rootViewController: ctrl)
        navCtrl.tabBarItem = .init(
            title: isSell ? L10n.TabBar.p2pSell : L10n.TabBar.p2pBuy,
            image: isSell ? Asset.mainP2pSell.image : Asset.mainP2pBuy.image,
            tag: 0
        )
        return navCtrl
    }

    override func tabBar(_ tabBar: UITabBar, didSelect item: UITabBarItem) {
        update?()
    }
    
    private func checkForAccountAvailability(wallet: WalletKit.Wallet?) {
        if !wallet.isExist {
            self.selectedIndex = UserDefaults.standard.bool(forKey: "chatsFirst") ? 1 : 0
        }
        
        self.tabBar.items?.forEach { $0.isEnabled = wallet.isExist }
    }

    func selectChatViewController() {
        self.selectedIndex = UserDefaults.standard.bool(forKey: "chatsFirst") ? 0 : 1
    }

    func setTabBarHidden(hidden: Bool, viewController: UIViewController? = nil) {
        self.tabBar.isHidden = hidden
        viewController?.view.setNeedsLayout()
    }
    
    private func setupMainControllerPresentation(on controller: UIViewController) {
        switch controller {
        case let vc where vc is WalletController,
                let vc where vc is CryptoChatControllerChats:
            self.changeMainControllerPresentation(visibility: true, isTabbarHidden: false)
        case let vc where vc is P2PControllerDashboard,
                let vc where vc is DeFiControllerMain:
            self.changeMainControllerPresentation(visibility: false, isTabbarHidden: false)
        default:
            self.changeMainControllerPresentation(visibility: false, 
                                                 isTabbarHidden: true, 
                                                 on: controller)
        }
    }
    
    private func changeMainControllerPresentation(visibility: Bool,
                                                  isTabbarHidden: Bool,
                                                  on controller: UIViewController? = nil) {
        self.mainController.inviteView.setupVisability(visibleOnController: visibility)
        self.mainController.view.layoutIfNeeded()
        self.setTabBarHidden(hidden: isTabbarHidden, viewController: controller)
    }
}

extension MainControllerContent: UINavigationControllerDelegate {
    func navigationController(_ navigationController: UINavigationController, willShow viewController: UIViewController, animated: Bool) {
        self.update?()
        self.setupMainControllerPresentation(on: viewController)
    }
}