//
//  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 {
    
    let tableView = StaticTableView(frame: .zero, style: .plain)
    var activePlans: [Subscription.PlanType] = []
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        do {
            view.addSubview(tableView)
            tableView.anchors.edges.pin()
            tableView.separatorStyle = .singleLine
            tableView.cellLayoutMarginsFollowReadableWidth = true
            tableView.deselectsCellsAutomatically = true
            tableView.contentInset.top += 12
            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)
                    }

                }
            }
        }
        
        let upgradeButton = DefaultButtonCell(title: NSLocalizedString("Loading Plan", comment: "Shows when loading the details of a subscription plan")) {
            self.performSegue(withIdentifier: "showUpgradePlanAccount", sender: self)
        }
        upgradeButton.startActivityIndicator()
        upgradeButton.button.isEnabled = false
        upgradeButton.selectionStyle = .none
        
        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 {
                upgradeButton.stopActivityIndicator()
            }.done { subscriptions in
                DDLogInfo("active-subs: \(subscriptions)")
                self.activePlans = subscriptions.map({ $0.planType })
                if let active = subscriptions.first {
                    if active.planType == .proAnnual {
                        upgradeButton.button.isEnabled = false
                        upgradeButton.selectionStyle = .none
                        upgradeButton.button.setTitle(NSLocalizedString("Plan: Annual Pro", comment: ""), for: UIControl.State())
                    } else {
                        upgradeButton.button.isEnabled = true
                        upgradeButton.selectionStyle = .default
                        upgradeButton.backgroundView?.backgroundColor = UIColor.tunnelsDarkBlue
                        upgradeButton.button.setTitleColor(UIColor.white, for: UIControl.State())
                        upgradeButton.button.setTitle(NSLocalizedString("View or Upgrade Plan", comment: ""), for: UIControl.State())
                    }
                } else {
                    upgradeButton.button.isEnabled = true
                    upgradeButton.selectionStyle = .default
                    upgradeButton.backgroundView?.backgroundColor = UIColor.tunnelsDarkBlue
                    upgradeButton.button.setTitleColor(UIColor.white, for: UIControl.State())
                    upgradeButton.button.setTitle(NSLocalizedString("View Upgrade Options", comment: ""), for: UIControl.State())
                }
            }
            .catch { error in
                if let apiError = error as? ApiError {
                    switch apiError.code {
                    case kApiCodeNoSubscriptionInReceipt, kApiCodeNoActiveSubscription:
                        upgradeButton.button.isEnabled = true
                        upgradeButton.selectionStyle = .default
                        upgradeButton.backgroundView?.backgroundColor = UIColor.tunnelsDarkBlue
                        upgradeButton.button.setTitleColor(UIColor.white, for: UIControl.State())
                        upgradeButton.button.setTitle(NSLocalizedString("View Upgrade Options", comment:""), for: UIControl.State())
                    case kApiCodeSandboxReceiptNotAllowed:
                        upgradeButton.button.isEnabled = true
                        upgradeButton.selectionStyle = .default
                        upgradeButton.backgroundView?.backgroundColor = UIColor.tunnelsDarkBlue
                        upgradeButton.button.setTitleColor(UIColor.white, for: UIControl.State())
                        upgradeButton.button.setTitle(NSLocalizedString("View Upgrade Options", comment:""), for: UIControl.State())
                    default:
                        DDLogError("Error loading plan: API error code - \(apiError.code)")
                        upgradeButton.button.isEnabled = true
                        upgradeButton.selectionStyle = .default
                        upgradeButton.button.setTitleColor(UIColor.systemRed, for: UIControl.State())
                        upgradeButton.button.setTitle(NSLocalizedString("Error Loading Plan: Retry", comment: ""), for: UIControl.State())
                        upgradeButton.onSelect {
                            self.reloadTable()
                        }
                    }
                } else {
                    DDLogError("Error loading plan: Non-API Error - \(error.localizedDescription)")
                    upgradeButton.button.isEnabled = true
                    upgradeButton.selectionStyle = .default
                    upgradeButton.button.setTitleColor(UIColor.systemRed, for: UIControl.State())
                    upgradeButton.button.setTitle(NSLocalizedString("Error Loading Plan: Retry", comment: ""), for: UIControl.State())
                    upgradeButton.onSelect {
                        self.reloadTable()
                    }
                }
            }
        }
        // not logged in via email, use receipt
        else {
            firstly {
                try Client.signIn()
            }.then { _ in
                try Client.activeSubscriptions()
            }.ensure {
                upgradeButton.stopActivityIndicator()
            }.done { subscriptions in
                self.activePlans = subscriptions.map({ $0.planType })
                if let active = subscriptions.first {
                    if active.planType == .proAnnual {
                        upgradeButton.button.isEnabled = false
                        upgradeButton.selectionStyle = .none
                        upgradeButton.button.setTitle(NSLocalizedString("Plan: Annual Pro", comment: ""), for: UIControl.State())
                    } else {
                        upgradeButton.button.isEnabled = true
                        upgradeButton.selectionStyle = .default
                        upgradeButton.backgroundView?.backgroundColor = UIColor.tunnelsDarkBlue
                        upgradeButton.button.setTitleColor(UIColor.white, for: UIControl.State())
                        upgradeButton.button.setTitle(NSLocalizedString("View or Upgrade Plan", comment: ""), for: UIControl.State())
                    }
                } else {
                    upgradeButton.button.isEnabled = true
                    upgradeButton.selectionStyle = .default
                    upgradeButton.backgroundView?.backgroundColor = UIColor.tunnelsDarkBlue
                    upgradeButton.button.setTitleColor(UIColor.white, for: UIControl.State())
                    upgradeButton.button.setTitle(NSLocalizedString("View Upgrade Options", comment: ""), for: UIControl.State())
                }
            }.catch { error in
                DDLogError("Error reloading subscription: \(error.localizedDescription)")
                if let apiError = error as? ApiError {
                    switch apiError.code {
                    case kApiCodeNoSubscriptionInReceipt, kApiCodeNoActiveSubscription:
                        upgradeButton.button.isEnabled = true
                        upgradeButton.selectionStyle = .default
                        upgradeButton.backgroundView?.backgroundColor = UIColor.tunnelsDarkBlue
                        upgradeButton.button.setTitleColor(UIColor.white, for: UIControl.State())
                        upgradeButton.button.setTitle(NSLocalizedString("View Upgrade Options", comment:""), for: UIControl.State())
                    case kApiCodeSandboxReceiptNotAllowed:
                        upgradeButton.button.isEnabled = true
                        upgradeButton.selectionStyle = .default
                        upgradeButton.backgroundView?.backgroundColor = UIColor.tunnelsDarkBlue
                        upgradeButton.button.setTitleColor(UIColor.white, for: UIControl.State())
                        upgradeButton.button.setTitle(NSLocalizedString("View Upgrade Options", comment:""), for: UIControl.State())
                    default:
                        DDLogError("Error loading plan: API error code - \(apiError.code)")
                        upgradeButton.button.isEnabled = true
                        upgradeButton.selectionStyle = .default
                        upgradeButton.button.setTitleColor(UIColor.systemRed, for: UIControl.State())
                        upgradeButton.button.setTitle(NSLocalizedString("Error Loading Plan: Retry", comment: ""), for: UIControl.State())
                        upgradeButton.onSelect {
                            self.reloadTable()
                        }
                    }
                } else {
                    DDLogError("Error loading plan: Non-API Error - \(error.localizedDescription)")
                    upgradeButton.button.isEnabled = true
                    upgradeButton.selectionStyle = .default
                    upgradeButton.button.setTitleColor(UIColor.systemRed, for: UIControl.State())
                    upgradeButton.button.setTitle(NSLocalizedString("Error Loading Plan: Retry", comment: ""), for: UIControl.State())
                    upgradeButton.onSelect {
                        self.reloadTable()
                    }
                }
            }
        }
        
        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,
            upgradeButton,
            notificationsButton,
        ]
        
        for cell in firstButtons {
            tableView.addCell(cell)
        }
        
        let otherCells = [
            DefaultCell(title: NSLocalizedString("Tutorial", comment: "")) { [unowned self] in
                self.startTutorial()
            },
            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 it's not answered there, we're happy to provide support and take feedback by email.", comment: ""),
                    buttons: [
                        .custom(title: NSLocalizedString("View FAQs", comment: ""), completion: {
                            self.showFAQsModal()
                        }),
                        .custom(title: NSLocalizedString("Email Us", comment: ""), completion: {
                            self.emailTeam()
                        }),
                        .cancel()
                    ]
                )
            },
            DefaultCell(title: NSLocalizedString("FAQs", comment: "")) {
                self.showFAQsModal()
            },
            DefaultCell(title: NSLocalizedString("Website", comment: "")) {
                self.showWebsiteModal()
            },
        ]
        
        for cell in otherCells {
            tableView.addCell(cell)
        }
        
        #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)?.homeViewController
            }
        case "showUpgradePlanAccount":
            if let vc = segue.destination as? SignupViewController {
                vc.parentVC = self
                if activePlans.isEmpty {
                    vc.mode = .newSubscription
                } else {
                    vc.mode = .upgrade(active: activePlans)
                }
            }
        default:
            break
        }
    }
}

// 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)
}

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()
            }
        }
    }
}