import Foundation
import monalxmpp

enum AccountsAvailability {
    case noAccounts
    case allDisabled
    case someEnabled
}

final class MonalXmppWrapper: ObservableObject {
    @Published var accountsAvailability: AccountsAvailability = .noAccounts

    private let xmpp: MLXMPPManager
    private let db: DataLayer

    init() {
        xmpp = MLXMPPManager.sharedInstance()
        db = DataLayer.sharedInstance()

        // here is some inits (just for now)
        MLProcessLock.initialize(forProcess: "MainApp")

        checkAccountsOnLoad()
    }

    // try login
    func tryLogin(_ login: String, _ password: String) async throws {
        let loginObject = LoginTry(xmpp: xmpp)
        let result = await loginObject.tryLogin(login, password)
        if !result {
            throw AimErrors.loginError
        }
    }
}

// MARK: - Accounts
private extension MonalXmppWrapper {
    // Check accounts state on launch
    func checkAccountsOnLoad() {
        let enabledAcocunts = db.enabledAccountList()
        let allAccounts = db.accountList()

        if allAccounts.isEmpty {
            accountsAvailability = .noAccounts
        } else if !enabledAcocunts.isEmpty {
            accountsAvailability = .someEnabled
        } else {
            accountsAvailability = .allDisabled
        }
    }
}

// MARK: - Login from Login screen
private final class LoginTry {
    weak var xmpp: MLXMPPManager?

    var successObserver: AnyObject?
    var failureObserver: AnyObject?

    init(xmpp: MLXMPPManager) {
        self.xmpp = xmpp
    }

    // TODO: Добавить автовключение отключенных аккаунтов при попытке ввести тот же JID\
    // Обработать кейс когда бесячий monalxmpp возвращает nil при попытке добавить тот же JID
    func tryLogin(_ login: String, _ password: String) async -> Bool {
        async let notify = await withCheckedContinuation { [weak self] continuation in
            self?.successObserver = NotificationCenter.default.addObserver(forName: Notification.Name("kMLResourceBoundNotice"), object: nil, queue: .main) { notification in
                print(notification.debugDescription)
                continuation.resume(returning: true)
            }
            self?.failureObserver = NotificationCenter.default.addObserver(forName: Notification.Name("kXMPPError"), object: nil, queue: .main) { notification in
                print(notification.debugDescription)
                continuation.resume(returning: false)
            }
        }

        defer {
            if let successObserver {
                NotificationCenter.default.removeObserver(successObserver)
            }
            if let failureObserver {
                NotificationCenter.default.removeObserver(failureObserver)
            }
        }

        let accountNumber = xmpp?.login(login, password: password)
        let result = await notify
        if let accountNumber, !result {
            xmpp?.removeAccount(forAccountID: accountNumber)
        }
        return result
    }
}