//
//  AccountVC.swift
//  Lockdown
//
//  Created by Oleg Dreyman on 02.10.2020.
//  Copyright © 2020 Confirmed Inc. All rights reserved.
//

import UIKit
import PopupDialog
import PromiseKit
import CocoaLumberjackSwift

final class AccountViewController: BaseViewController, Loadable {
    
    // MARK: - Properties
    let tableView = StaticTableView(frame: .zero, style: .grouped)
    var activePlans: [Subscription.PlanType] = []
    var feedbackFlow: FeedbackFlow?

    override func viewDidLoad() {
        super.viewDidLoad()
        
        view.backgroundColor = .systemBackground
        
        do {
            view.addSubview(tableView)
            tableView.anchors.edges.pin()
            tableView.separatorStyle = .singleLine
            tableView.cellLayoutMarginsFollowReadableWidth = true
            tableView.deselectsCellsAutomatically = true
            tableView.tableFooterView = UIView()
            
            tableView.clear()
            createTable()
        }
        
        do {
            NotificationCenter.default.addObserver(self, selector: #selector(accountStateDidChange), name: AccountUI.accountStateDidChange, object: nil)
        }
    }
    
    @objc
    func accountStateDidChange() {
        assert(Thread.isMainThread)
        self.reloadTable()
    }
    
    func reloadTable() {
        tableView.clear()
        createTable()
        tableView.reloadData()
    }
    
    func createTable() {
        var title = NSLocalizedString("⚠️ Not Signed In", comment: "")
        var message: String? = NSLocalizedString("Sign up below to unlock benefits of a Lockdown account.", comment: "")
        var firstButton = DefaultCell(title: NSLocalizedString("Sign Up  |  Sign In", comment: "")) {
            // AccountViewController will update itself by observing
            // AccountUI.accountStateDidChange notification
            AccountUI.presentCreateAccount(on: self)
        }
        firstButton.backgroundView = UIView()
        firstButton.backgroundView?.backgroundColor = UIColor.tunnelsBlue
        firstButton.label.textColor = UIColor.white
        
        if let apiCredentials = getAPICredentials() {
            message = apiCredentials.email
            if getAPICredentialsConfirmed() == true {
                title = NSLocalizedString("Signed In", comment: "")
                firstButton = DefaultCell(title: NSLocalizedString("Sign Out", comment: "")) {
                    let confirm = PopupDialog(title: NSLocalizedString("Sign Out?", comment: ""),
                                              message: NSLocalizedString("You'll be signed out from this account.", comment: ""),
                                              image: nil,
                                              buttonAlignment: .horizontal,
                                              transitionStyle: .bounceDown,
                                              preferredWidth: 270,
                                              tapGestureDismissal: true,
                                              panGestureDismissal: false,
                                              hideStatusBar: false,
                                              completion: nil)
                    confirm.addButtons([
                        DefaultButton(title: NSLocalizedString("Cancel", comment: ""), dismissOnTap: true) {
                        },
                        DefaultButton(title: NSLocalizedString("Sign Out", comment: ""), dismissOnTap: true) { [unowned self] in
                            URLCache.shared.removeAllCachedResponses()
                            Client.clearCookies()
                            clearAPICredentials()
                            setAPICredentialsConfirmed(confirmed: false)
                            self.reloadTable()
                            self.showPopupDialog(title: NSLocalizedString("Success", comment: ""), message: NSLocalizedString("Signed out successfully.", comment: ""), acceptButton: NSLocalizedString("Okay", comment: ""))
                        },
                    ])
                    self.present(confirm, animated: true, completion: nil)
                }
                firstButton.backgroundView?.backgroundColor = UIColor.clear
                firstButton.label.textColor = UIColor.systemRed
            }
            else {
                title = "⚠️ Email Not Confirmed"
                firstButton = DefaultCell(title: NSLocalizedString("Confirm Email", comment: "")) {
                    self.showLoadingView()
                    
                    firstly {
                        try Client.signInWithEmail(email: apiCredentials.email, password: apiCredentials.password)
                    }
                    .done { (signin: SignIn) in
                        self.hideLoadingView()
                        // successfully signed in with no errors, show confirmation success
                        setAPICredentialsConfirmed(confirmed: true)
                        
                        // logged in and confirmed - update this email with the receipt and refresh VPN credentials
                        firstly { () -> Promise<SubscriptionEvent> in
                            try Client.subscriptionEvent()
                        }
                        .then { (result: SubscriptionEvent) -> Promise<GetKey> in
                            try Client.getKey()
                        }
                        .done { (getKey: GetKey) in
                            try setVPNCredentials(id: getKey.id, keyBase64: getKey.b64)
                            if (getUserWantsVPNEnabled() == true) {
                                VPNController.shared.restart()
                            }
                        }
                        .catch { error in
                            // it's okay for this to error out with "no subscription in receipt"
                            DDLogError("HomeViewController ConfirmEmail subscriptionevent error (ok for it to be \"no subscription in receipt\"): \(error)")
                        }
                        
                        let popup = PopupDialog(title: "Success! 🎉",
                                                message: NSLocalizedString("Your account has been confirmed and you're now signed in. You'll get the latest block lists, access to Lockdown Mac, and get critical announcements.", comment: ""),
                                                image: nil,
                                                buttonAlignment: .horizontal,
                                                transitionStyle: .bounceDown,
                                                preferredWidth: 270,
                                                tapGestureDismissal: true,
                                                panGestureDismissal: false,
                                                hideStatusBar: false,
                                                completion: nil)
                        popup.addButtons([
                            DefaultButton(title: NSLocalizedString("Okay", comment: ""), dismissOnTap: true) {
                                self.reloadTable()
                            }
                        ])
                        self.present(popup, animated: true, completion: nil)
                    }
                    .catch { error in
                        self.hideLoadingView()
                        let popup = PopupDialog(title: NSLocalizedString("Check Your Inbox", comment: ""),
                                                message: "\(NSLocalizedString("To complete your signup, click the confirmation link we sent to", comment: "Used in To complete your signup, click the confirmation link we sent to you@gmail.com")) \(apiCredentials.email). \(NSLocalizedString("Be sure to check your spam folder in case it got stuck there.\n\nYou can also request a re-send of the confirmation.", comment: ""))",
                                                image: nil,
                                                buttonAlignment: .vertical,
                                                transitionStyle: .bounceDown,
                                                preferredWidth: 270,
                                                tapGestureDismissal: true,
                                                panGestureDismissal: false,
                                                hideStatusBar: false,
                                                completion: nil)
                        popup.addButtons([
                            DefaultButton(title: NSLocalizedString("Okay", comment: ""), dismissOnTap: true) {},
                            DefaultButton(title: NSLocalizedString("Sign Out", comment: ""), dismissOnTap: true) {
                                URLCache.shared.removeAllCachedResponses()
                                Client.clearCookies()
                                clearAPICredentials()
                                setAPICredentialsConfirmed(confirmed: false)
                                self.reloadTable()
                                self.showPopupDialog(title: NSLocalizedString("Success", comment: ""), message: NSLocalizedString("Signed out successfully.", comment: ""), acceptButton: NSLocalizedString("Okay", comment: ""))
                            },
                            DefaultButton(title: NSLocalizedString("Re-send", comment: ""), dismissOnTap: true) {
                                firstly {
                                    try Client.resendConfirmCode(email: apiCredentials.email)
                                }
                                .done { (success: Bool) in
                                    var message = NSLocalizedString("Successfully re-sent your email confirmation to ", comment: "") + apiCredentials.email
                                    if (success == false) {
                                        message = NSLocalizedString("Failed to re-send email confirmation.", comment: "")
                                    }
                                    self.showPopupDialog(title: "", message: message, acceptButton: NSLocalizedString("Okay", comment: ""))
                                }
                                .catch { error in
                                    if (self.popupErrorAsNSURLError(error)) {
                                        return
                                    }
                                    else if let apiError = error as? ApiError {
                                        _ = self.popupErrorAsApiError(apiError)
                                    }
                                    else {
                                        self.showPopupDialog(title: NSLocalizedString("Error Re-sending Email Confirmation", comment: ""),
                                                             message: "\(error)",
                                                             acceptButton: NSLocalizedString("Okay", comment: ""))
                                    }
                                }
                            },
                        ])
                        self.present(popup, animated: true, completion: nil)
                    }
                    
                }
            }
        }
        
        self.activePlans = []
        
        // show the plan status/button - first check and sync email if it's confirmed, otherwise just use receipt
        if let apiCredentials = getAPICredentials(), getAPICredentialsConfirmed() == true {
            DDLogInfo("plan status: have confirmed API credentials, using them")
            firstly {
                try Client.signInWithEmail(email: apiCredentials.email, password: apiCredentials.password)
            }
            .then { (signin: SignIn) -> Promise<SubscriptionEvent> in
                DDLogInfo("plan status: signin result: \(signin)")
                return try Client.subscriptionEvent()
            }
            .then { (result: SubscriptionEvent) -> Promise<[Subscription]> in
                DDLogInfo("plan status: subscriptionevent result: \(result)")
                return try Client.activeSubscriptions()
            }.ensure {
            }.done { subscriptions in
                DDLogInfo("active-subs: \(subscriptions)")
                self.activePlans = subscriptions.map({ $0.planType })
            }
            .catch { error in
            }
        }
        // not logged in via email, use receipt
        else {
            firstly {
                try Client.signIn()
            }.then { _ in
                try Client.activeSubscriptions()
            }.ensure {
            }.done { subscriptions in
                self.activePlans = subscriptions.map({ $0.planType })
            }.catch { error in
                DDLogError("Error reloading subscription: \(error.localizedDescription)")
            }
        }
        
        let notificationsButton = DefaultCell(title: "", action: { })
        
        let updateNotificationButtonTitle = { (cell: _DefaultCell) in
            if PushNotifications.Authorization.getUserWantsNotificationsEnabled(forCategory: .weeklyUpdate) {
                cell.label.text = NSLocalizedString("Notifications: On", comment: "")
            } else {
                cell.label.text = NSLocalizedString("Notifications: Off", comment: "")
            }
        }
        
        updateNotificationButtonTitle(notificationsButton)
        
        notificationsButton.onSelect { [unowned notificationsButton, unowned self] in
            if PushNotifications.Authorization.getUserWantsNotificationsEnabled(forCategory: .weeklyUpdate) {
                PushNotifications.Authorization.setUserWantsNotificationsEnabled(false, forCategory: .weeklyUpdate)
                updateNotificationButtonTitle(notificationsButton)
            } else {
                PushNotifications.Authorization.requestWeeklyUpdateAuthorization(presentingDialogOn: self).done { status in
                    DDLogInfo("New authorization status for push notifications: \(status)")
                    updateNotificationButtonTitle(notificationsButton)
                }.catch { error in
                    DDLogError("Error updating notification authorization status: \(error.localizedDescription)")
                }
            }
        }
        
        tableView.addRow { (contentView) in
            let stack = UIStackView()
            stack.axis = .vertical
            stack.spacing = 8
            contentView.addSubview(stack)
            stack.anchors.edges.marginsPin(insets: .init(top: 8, left: 0, bottom: 8, right: 0))
            
            let titleLabel = UILabel()
            titleLabel.text = title
            titleLabel.font = fontBold18
            titleLabel.textAlignment = .center
            titleLabel.numberOfLines = 0
            stack.addArrangedSubview(titleLabel)
            
            let messageLabel = UILabel()
            messageLabel.text = message
            messageLabel.font = fontMedium18
            messageLabel.textAlignment = .center
            messageLabel.numberOfLines = 0
            stack.addArrangedSubview(messageLabel)
        }
        
        let firstButtons: [SelectableTableViewCell] = [
            firstButton,
            notificationsButton,
        ]
        
        for cell in firstButtons {
            tableView.addCell(cell)
        }
        
        let otherCells = [
            //            DefaultCell(title: NSLocalizedString("Tutorial", comment: "")) { [unowned self] in
            //                self.startTutorial()
            //            },
            MakeDefaultCell(
                title: NSLocalizedString("What's New", comment: ""),
                color: .paywallNew
            ) {
                self.showWhatsNewModal()
            },
            DefaultCell(title: NSLocalizedString("Why Trust Lockdown", comment: "")) {
                self.showWhyTrustPopup()
            },
            DefaultCell(title: NSLocalizedString("Privacy Policy", comment: "")) {
                self.showPrivacyPolicyModal()
            },
            DefaultCell(title: NSLocalizedString("What is VPN?", comment: "")) {
                self.performSegue(withIdentifier: "showWhatIsVPN", sender: self)
            },
            DefaultCell(title: NSLocalizedString("Support | Feedback", comment: "")) {
                self.showPopupDialog(
                    title: nil,
                    message: NSLocalizedString("Remember to check our FAQs first for answers to the most frequently asked questions.\n\nIf your question is not answered there, we're happy to provide support and receive feedback via email or through the bug reporting form.", comment: ""),
                    buttons: [
                        .custom(title: NSLocalizedString("View FAQs", comment: ""), completion: {
                            self.showFAQsModal()
                        }),
                        .custom(title: NSLocalizedString("Email Us", comment: ""), completion: {
                            self.emailTeam()
                        }),
                        .custom(title: NSLocalizedString("Bug Reporting Form", comment: "")) { [weak self] in
                            self?.openQuestionnaire()
                        },
                        .cancel()
                    ]
                )
            },
            DefaultCell(title: NSLocalizedString("FAQs", comment: "")) {
                self.showFAQsModal()
            },
            DefaultCell(title: NSLocalizedString("Website", comment: "")) {
                self.showWebsiteModal()
            },
        ]
        
        for cell in otherCells {
            tableView.addCell(cell)
        }
        
        if let creds = getAPICredentials() {
            tableView.addCell(MakeDefaultCell(
                title: .localized("delete_account"),
                color: .lockdownRed
            ) {
                self.deleteAccount(userEmail: creds.email)
            })
        }
        
#if DEBUG
        let fixVPNConfig = DefaultCell(title: "_Fix Firewall Config", action: {
            self.showFixFirewallConnectionDialog {
                FirewallController.shared.deleteConfigurationAndAddAgain()
            }
        })
        tableView.addCell(fixVPNConfig)
#endif
        
        tableView.addRowCell { (cell) in
            cell.textLabel?.text = Bundle.main.versionString
            cell.textLabel?.font = fontSemiBold17
            cell.textLabel?.textColor = UIColor.systemGray
            cell.textLabel?.textAlignment = .right
            
            // removing the bottom separator
            cell.separatorInset = .init(top: 0, left: 0, bottom: 0, right: .greatestFiniteMagnitude)
            cell.directionalLayoutMargins = .zero
        }
    }
    
    func startTutorial() {
//        if let tabBarController = tabBarController as? MainTabBarController {
//            tabBarController.selectedViewController = tabBarController.homeViewController
//            tabBarController.homeViewController.startTutorial()
//        }
    }
    
    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        switch segue.identifier {
        case "showWhatIsVPN":
            if let vc = segue.destination as? WhatIsVpnViewController {
//                vc.parentVC = (tabBarController as? MainTabBarController)?.vpnViewController
            }
        default:
            break
        }
    }
    
    private func openQuestionnaire() {
        feedbackFlow?.startFlow()
    }
}

// MARK: - Helpers / Extensions

class _DefaultButtonCell: SelectableTableViewCell {
    let button = UIButton(type: .system)
}

func DefaultButtonCell(title: String, action: @escaping () -> ()) -> _DefaultButtonCell {
    let cell = _DefaultButtonCell()
    cell.backgroundView = UIView()
    cell.button.setTitle(title, for: .normal)
    cell.button.isUserInteractionEnabled = false
    cell.button.titleLabel?.font = fontSemiBold17
    cell.button.tintColor = .tunnelsBlue
    cell.contentView.addSubview(cell.button)
    cell.button.anchors.height.equal(21)
    cell.button.anchors.edges.marginsPin(insets: .init(top: 8, left: 0, bottom: 8, right: 0))
    return cell.onSelect(callback: action)
}

class _DefaultCell: SelectableTableViewCell {
    let label = UILabel()
}

func DefaultCell(title: String, action: @escaping () -> ()) -> _DefaultCell {
    let cell = _DefaultCell()
    cell.label.text = title
    cell.label.font = fontSemiBold17
    cell.label.textColor = .tunnelsBlue
    cell.label.textAlignment = .center
    cell.contentView.addSubview(cell.label)
    cell.label.anchors.edges.marginsPin(insets: .init(top: 8, left: 0, bottom: 8, right: 0))
    return cell.onSelect(callback: action)
}

func MakeDefaultCell(title: String, color: UIColor = .tunnelsBlue, action: @escaping () -> Void) -> _DefaultCell {
    let cell = _DefaultCell()
    cell.label.text = title
    cell.label.font = .semiboldLockdownFont(size: 17)
    cell.label.textColor = color
    cell.label.textAlignment = .center
    cell.contentView.addSubview(cell.label)
    cell.label.anchors.edges.marginsPin(insets: .init(top: 8, left: 0, bottom: 8, right: 0))
    return cell.onSelect(callback: action)
}

extension AccountViewController: EmailComposable {
    private func deleteAccount(userEmail: String) {
        let deleteAccountViewController = DeleteMyAccountViewController(userEmail: userEmail)
        deleteAccountViewController.modalPresentationStyle = .formSheet
        present(deleteAccountViewController, animated: true)
    }
}

fileprivate extension _DefaultButtonCell {
    func startActivityIndicator() {
        let activity = UIActivityIndicatorView()
        
        if let label = button.titleLabel {
            label.addSubview(activity)
            activity.translatesAutoresizingMaskIntoConstraints = false
            activity.centerYAnchor.constraint(equalTo: label.centerYAnchor).isActive = true
            activity.leadingAnchor.constraint(equalToSystemSpacingAfter: label.trailingAnchor, multiplier: 1).isActive = true
            activity.startAnimating()
        }
    }
    
    func stopActivityIndicator() {
        if let label = button.titleLabel {
            let indicators = label.subviews.compactMap { $0 as? UIActivityIndicatorView }
            for indicator in indicators {
                indicator.stopAnimating()
                indicator.removeFromSuperview()
            }
        }
    }
}
