//
//  CryptoChatControllerChats.swift
//  PayCash
//
//  Created by Saveliy Stavitsky on 8/17/20.
//  Copyright © 2020 List. All rights reserved.
//

import UIKit
import IQKeyboardManagerSwift
import EosioSwift
import Branch

import struct RealmSwift.Results

class CryptoChatControllerChats: UIViewController {
    
    @IBOutlet private weak var tableView: UITableView!
    @IBOutlet weak var headerContainerView: UIView!
    @IBOutlet weak var addChatButton: UIButton!
    @IBOutlet weak var chatsListLabel: UILabel!

    var msgsHistoryService: CryptoChat.Service.MsgsHistory?

    private let refreshControl = UIRefreshControl()

    let header = CryptoChatViewChatsHeader(width: UIScreen.main.bounds.width, height: 120)
    var chats: Results<CryptoChatModelRealmChat>?
    var msgs: Results<CryptoChatModelRealmMessage>?
    
    private lazy var noAccountsView: CommonViewEmpty = {
        CommonViewEmpty(
            title: L10n.CryptoChat.Chats.NoAccounts.title,
            text: L10n.Account.Empty.text,
            image: Asset.accountEmpty.image,
            backgroundColor: Asset.snow.color,
            submit: L10n.Account.Empty.submit
        ) { [weak self] in
            guard let self = self else { return }
            AccountController.showPopup(in: self)
        }
    }()

    private lazy var emptyView: CommonViewEmpty = {
        CommonViewEmpty(
            title: L10n.CryptoChat.Chats.Empty.title,
            text: L10n.CryptoChat.Chats.Empty.text,
            image: Asset.chatsEmpty.image,
            submit: L10n.CryptoChat.Chats.Empty.submit,
            submitRealtion: .top
        ) { [weak self] in
            guard let self = self else { return }
            self.showSelectChatAddMethodPopup()
        }
    }()

    private lazy var encodedView: CommonViewEmpty = {
        CommonViewEmpty(
            title: L10n.CryptoChat.Chats.Encoded.title,
            text: L10n.CryptoChat.Chats.encoded,
            image: Asset.chatsLocked.image,
            submit: L10n.CryptoChat.Chats.encodedButton,
            submitRealtion: .top
        ) { [weak self] in
            guard let self = self else { return }
            self.onAccountChange(Notification(name: .didChangeAccount))
        }
    }()

    var bottomSpace: CGFloat = 0

    override func viewDidLoad() {
        super.viewDidLoad()
        
        navigationController?.interactivePopGestureRecognizer?.delegate = nil

        navigationItem.title = L10n.CryptoChat.Chats.title

        tableView.showsVerticalScrollIndicator = false
        tableView.separatorStyle = .none
        (tableView as UIScrollView).delegate = self

        tableView.register(cell: CryptoChatCellChat.self)

        refreshControl.addTarget(self, action: #selector(self.refresh(_:)), for: .valueChanged)
        tableView.addSubview(refreshControl)

        Notification.subscribe(name: .didUpdateHistory, {
            guard Accounts().current?.username == $0.userInfo?["username"] as? String else { return }
            self.msgsHistoryService?.fetchFromLocalHistory()
        })
        
        self.addChatButton.addTarget(self, action: #selector(self.addButtonPressed(_:)), for: .touchUpInside)
        
        self.setupView()
    }

    func setup(username: String) {
        AccountViewAuthorize.showGetPrivateKey(in: self, { [weak self] privateKey in
            self?.msgsHistoryService = try? CryptoChat.Service
                .MsgsHistory(username: username, encryptionKey: privateKey)
            self?.msgsHistoryService?.didUpdate = { [weak self] in
                DispatchQueue.main.async {
                    self?.refreshControl.endRefreshing()
                    self?.tableView.reloadData()
                }
            }
            self?.chats = self?.msgsHistoryService?.chats
            self?.msgs = self?.msgsHistoryService?.filterMsgs(query: "")
            self?.header.searchTextField.text = ""
            self?.tableView.reloadData()
            Account.Service.History.shared.current?.fetch()
        })
    }
    
    @objc
    func addButtonPressed(_ sender: Any) {
        self.showSelectChatAddMethodPopup()
    }

    @objc func onAccountChange(_ notification: Notification) {
        if let username = Accounts().current?.username {
            msgsHistoryService = nil
            chats = nil
            msgs = nil
            tableView.reloadData()

            setup(username: username)
        }
        Accounts().exists ? noAccountsView.removeFromSuperview() : view.addSubview(noAccountsView)
    }

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        Accounts().exists ? noAccountsView.removeFromSuperview() : view.addSubview(noAccountsView)
        NotificationCenter.default.addObserver(self, selector: #selector(onAccountChange(_:)), name: .didChangeAccount, object: nil)

        navigationController?.setNavigationBarHidden(true, animated: animated)
//        IQKeyboardManager.shared.enable = false

        refresh(self)

        if ((UIApplication.shared.windows.first!.rootViewController as? MainController)?.barNav.items?.count ?? 0) > 1 {
            (UIApplication.shared.windows.first!.rootViewController as? MainController)?.barNav.popItem(animated: true)
        }
    }

    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)

        NotificationCenter.default.removeObserver(self, name: .didChangeAccount, object: nil)
        msgsHistoryService = nil
        chats = nil
        msgs = nil
        tableView.reloadData()
        navigationController?.setNavigationBarHidden(false, animated: animated)
//        IQKeyboardManager.shared.enable = true
    }
    
    override func viewDidLayoutSubviews() {
        super.viewDidLayoutSubviews()
        if bottomSpace == 0 {
            bottomSpace += (self.tabBarController?.tabBar.frameHeight ?? 0) /*tab bar*/
                + 40 /*button height*/ + 24 /*button top space*/
        }
        noAccountsView.frame = tableView.frame
        emptyView.frame = tableView.frame
        encodedView.frame = tableView.frame
    }
    
    private func setupView() {
        self.addChatButton.layer.borderColor = Asset.deepWater.color.withAlphaComponent(0.2).cgColor
        self.addChatButton.layer.borderWidth = 1.0
        self.addChatButton.layer.cornerRadius = 8.0
    }

    @objc func refresh(_ sender: AnyObject) {
        guard let username = Accounts().current?.username else { return }
        if msgsHistoryService == nil {
            setup(username: username)
        } else {
            Account.Service.History.shared.current?.fetch()
        }
    }
    
    func openChat(username: String, unreadCount: Int) {
        guard username.count > 0, msgsHistoryService != nil else { return }
        let chatViewController = CryptoChatControllerChat()
        chatViewController.username = username
        chatViewController.msgsHistoryService = msgsHistoryService
        chatViewController.unreadCount = unreadCount
    
        mainController.content.push(chatViewController, animated: true)
    }
    
    var query = ""
}

extension CryptoChatControllerChats: UITableViewDelegate, UITableViewDataSource {

    func numberOfSections(in tableView: UITableView) -> Int {
        1 + ((msgs?.count ?? 0) > 0 ? 1 : 0)
    }

    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        if Accounts().current != nil {
            if msgsHistoryService == nil {
                emptyView.removeFromSuperview()
                Loader.hide(in: tableView)
                view.addSubview(encodedView)
            } else {
                if !UserDefaults.standard.bool(forKey: "\(Accounts().current!.username)_firstMsgsSyncDone") {
                    Loader.show(in: tableView)
                } else {
                    Loader.hide(in: tableView)
                    (chats?.count ?? 0) == 0 && query.isEmpty ? view.addSubview(emptyView) : emptyView.removeFromSuperview()
                }
                encodedView.removeFromSuperview()
            }
            [
                self.addChatButton,
                self.header.searchTextField
            ]
            .forEach {
                $0?.isHidden = (msgsHistoryService == nil)
                    || !UserDefaults.standard.bool(forKey: "\(Accounts().current!.username)_firstMsgsSyncDone")
                    || ((chats?.count ?? 0) == 0 && query.isEmpty)
            }
        } else {
            Loader.hide(in: tableView)
            emptyView.removeFromSuperview()
            encodedView.removeFromSuperview()
        }
        return section == 0 ? (chats?.count ?? 0) : (msgs?.count ?? 0)
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(CryptoChatCellChat.self, indexPath: indexPath)
        
        if indexPath.section == 0 {
            guard let chat = chats?[indexPath.row] else { return cell }

            cell.titleLabel.text = chat.chatName
            cell.titleShortLabel.text = String(chat.chatName.prefix(3))
            cell.descriptionLabel.text = chat.textDescription
            cell.timeLabel.text = chat.time
            cell.setUnread(count: chat.unreadCount)
        } else {
            guard let msg = msgs?[indexPath.row] else { return cell }

            cell.titleLabel.text = msg.chatName
            cell.titleShortLabel.text = String(msg.chatName.prefix(3))
            cell.descriptionLabel.text = msg.textDescription
            cell.timeLabel.text = msg.time
            cell.setUnread(count: nil)
        }

        return cell
    }

    func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
        if section == 0 {
            header.parent = self
            header.searchTextField.delegate = self
            return header
        } else {
            let button = CommonButtonAction(width: UIScreen.main.bounds.width, height: 40)
            button.style = .secondary
            button.backgroundColor = Asset.deepWater.color.withAlphaComponent(0.1)
            button.isUserInteractionEnabled = false
            button.contentEdgeInsets = UIEdgeInsets(top: 0, left: 24, bottom: 0, right: 24)
            button.cornerRadius = 0
            button.setTitle(L10n.CryptoChat.Chats.Search.msgsSection, for: .normal)
            button.setTitleColor(Asset.textDeepWater.color, for: .normal)
            button.titleLabel?.font = Font.font(style: .bold, size: 12)
            button.contentHorizontalAlignment = .left
            return UIStackView(subviews: [UIView(height: 16, color: .white), button], axis: .vertical, distribution: .fill, alignment: .fill, spacing: 0)
        }
    }

    func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat {
        section == 0 ? 65 : 56
    }

    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        tableView.deselectRow(at: indexPath, animated: true)

        if indexPath.section == 0 {
            guard let chat = chats?[indexPath.row] else { return }
            openChat(username: chat.chatName, unreadCount: chat.unreadCount)
        } else {
            guard let msg = msgs?[indexPath.row] else { return }
            openChat(username: msg.chatName, unreadCount: 0)
        }
    }

    func tableView(_ tableView: UITableView, viewForFooterInSection section: Int) -> UIView? {
        if (msgs?.count ?? 0) > 0 {
            return section == 1 ? UIView(height: 56, color: .white) : UIView(height: 0)
        } else {
            return UIView(height: 56, color: .white)
        }
    }

    func tableView(_ tableView: UITableView, heightForFooterInSection section: Int) -> CGFloat {
        section == 1 ? 56 : 0
    }
    
    func tableView(_ tableView: UITableView, editActionsForRowAt indexPath: IndexPath) -> [UITableViewRowAction]? {
        
        if !query.isEmpty { return nil }
        guard let chat = chats?[indexPath.row] else { return nil }
        
        let delete = UITableViewRowAction(style: .destructive, title: L10n.Common.Button.delete) { [weak self] (action, indexPath) in
            self?.msgsHistoryService?.hideChatMsgs(chatName: chat.chatName)
        }

        return [delete]
    }
}

extension CryptoChatControllerChats: CommonTextFieldSearchDelegate {

    func textField(_ textField: CommonTextFieldSearch, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
        if let text = textField.text {
            let updatedText = (text as NSString).replacingCharacters(in: range, with: string)
            if updatedText.isEmpty {
                chats = msgsHistoryService?.chats
                msgs = msgsHistoryService?.filterMsgs(query: "")
                query = ""
            } else {
                chats = msgsHistoryService?.filterChats(query: updatedText)
                msgs = msgsHistoryService?.filterMsgs(query: updatedText)
                query = updatedText
            }
        } else {
            chats = msgsHistoryService?.chats
            msgs = msgsHistoryService?.filterMsgs(query: "")
            query = ""
        }
        
        tableView.reloadData()

        return true
    }

    func textFieldShouldClear(_ textField: CommonTextFieldSearch) -> Bool {
        chats = msgsHistoryService?.chats
        msgs = msgsHistoryService?.filterMsgs(query: "")
        query = ""
        tableView.reloadData()
        return true
    }
}

// MARK: - Opening QR to select New Chat Add Method
extension CryptoChatControllerChats: UIImagePickerControllerDelegate, UINavigationControllerDelegate {
    func showSelectChatAddMethodPopup() {
        let alert = UIAlertController(title: nil, message: nil, preferredStyle: .actionSheet)
        
        let openScannerAction: ((UIAlertAction) -> Void) = { [weak self] _ in
            self?.openScannerQrViewController { [weak self] in
                self?.dismiss(animated: true)
                let username = self?.injectUsername(string: $0) ?? .init()
                guard !username.isEmpty else { return }
                
                switch username {
                case let username where URL(string: username)?.absoluteString.contains("app.link") ?? false:
                    Branch.getInstance().application(UIApplication.shared, open: URL(string: username), options: nil)
                default:
                    self?.validateEosAccount(username: username)
                }
            }
        }

        let cryptoChatCreateAction: ((UIAlertAction) -> Void) = { [weak self] _ in
            self?.openCryptoChatCreatePopup()
        }

        let imagePickerAction: ((UIAlertAction) -> Void) = { [weak self] _ in
            self?.openImagePickerViewController()
        }

        alert.addAction(.init(title: L10n.CryptoChat.Chats.Popup.findAccount, style: .default, handler: cryptoChatCreateAction))

        if UIImagePickerController.isSourceTypeAvailable(.photoLibrary) {
            alert.addAction(.init(title: L10n.CryptoChat.Chats.Popup.qrLibrary, style: .default, handler: imagePickerAction))
        }

        if UIImagePickerController.isSourceTypeAvailable(.camera) {
            alert.addAction(.init(title: L10n.CryptoChat.Chats.Popup.qrCamera, style: .default, handler: openScannerAction))
        }

        alert.addAction(.init(title: L10n.Common.Button.cancel, style: .cancel, handler: nil))
        self.present(alert, animated: true)
    }
    
    private func injectUsername(string: String) -> String? {
        guard let stringData = string.data(using: .utf8) else { return string }
        let addressDecoder = try? JSONDecoder().decode(WalletTansferQr.self, from: stringData)

        return addressDecoder?.address ?? string
    }
    
    private func validateEosAccount(username: String) {
        EosioRpcProvider(endpoint: URL(string: Network.servers.current.node)!).getAccount(requestParameters: EosioRpcAccountRequest(accountName: username), completion: { [weak self] in
            switch $0 {
            case .success:
                self?.openChat(username: username, unreadCount: 0)
            case .failure:
                Alert.error(text: L10n.CryptoChat.Chats.createTextFieldError)
            }
        })
    }

    // MARK: UIImagePickerControllerDelegate & UINavigationControllerDelegate delegate methods
    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
        self.dismiss(animated: true, completion: nil)

        if let selectedImage = info[.originalImage] as? UIImage,
           let detector = CIDetector(ofType: CIDetectorTypeQRCode, context: nil, options: [CIDetectorAccuracy: CIDetectorAccuracyHigh]),
           let ciImage = CIImage(image: selectedImage) {
            
            let qrCodeString =
                (detector.features(in: ciImage) as? [CIQRCodeFeature])?
                .compactMap(\.messageString)
                .joined()
                ?? String.init()

            guard let username = self.injectUsername(string: qrCodeString) else {
                return
            }
            
            guard !username.isEmpty else {
                Alert.error(text: L10n.CryptoChat.Chats.noQr, delay: 1)
                return
            }
            
            switch username {
            case let username where URL(string: username)?.absoluteString.contains("app.link") ?? false:
                Branch.getInstance().application(UIApplication.shared, open: URL(string: username), options: nil)
            default:
                self.validateEosAccount(username: username)
            }
        }
    }
}

// MARK: - Routing
extension CryptoChatControllerChats {
    fileprivate func openImagePickerViewController() {
        let imagePicker =  UIImagePickerController()
        imagePicker.delegate = self
        imagePicker.sourceType = .photoLibrary
        self.present(imagePicker, animated: true, completion: nil)
    }

    fileprivate func openCryptoChatCreatePopup() {
        let view = CryptoChatViewCreateChat()
        view.parent = self
        Popup.show(content: CommonViewControllerViewPopUp(
            title: L10n.CryptoChat.Chats.craateDescription,
            image: Asset.chatCreate.image,
            view: view
        ))
    }

    fileprivate func openScannerQrViewController(onAction: @escaping (String) -> Void) {
        let scanner = ScannerViewController()

        scanner.navigationItem.leftBarButtonItem = .close { [weak self] in
            self?.dismiss(animated: true)
        }

        scanner.didCapture = onAction

        let navCtrl = UINavigationController(rootViewController: scanner)
        navCtrl.modalPresentationStyle = .fullScreen
        self.navigationController?.tabBarController?.present(navCtrl, animated: true)
    }
}