import Foundation
import monalxmpp

final class WrapperChat: ObservableObject {
    @Published private(set) var messages: [Message] = []
    @Published var replyText: String = ""
    @Published private(set) var mamRequestInProgress = false
    @Published var isOmemoEnabled: Bool {
        didSet {
            toggleOmemo(isOmemoEnabled)
        }
    }

    let contact: Contact

    private let monalContact: MLContact
    private let account: Account
    private let xmpp: MLXMPPManager
    private let db: DataLayer
    private var notificationObservers: [AnyObject] = []

    init(account: Account, contact: Contact, db: DataLayer, xmpp: MLXMPPManager) {
        self.contact = contact
        self.account = account
        self.db = db
        self.xmpp = xmpp

        // swiftlint:disable:next force_unwrapping
        monalContact = db.contactList().first { $0.accountID.intValue == contact.ownerId && $0.contactJid == contact.contactJid }!
        isOmemoEnabled = monalContact.isEncrypted

        subscribe()
        NotificationCenter.default.post(name: Notification.Name(kMonalNewMessageNotice), object: nil)

        //
    }

    deinit {
        notificationObservers.forEach { NotificationCenter.default.removeObserver($0) }
    }

    var chatTitle: String {
        contact.name
    }

    func sendText(_ text: String) {
        let newMessageId = UUID().uuidString
        _ = db.addMessageHistory(
            to: contact.contactJid,
            forAccount: monalContact.accountID,
            withMessage: text,
            actuallyFrom: account.jid,
            withId: newMessageId,
            encrypted: monalContact.isEncrypted,
            messageType: kMessageTypeText,
            mimeType: nil,
            size: nil
        )
        print(newMessageId)
        xmpp.sendMessage(text, to: monalContact, isEncrypted: monalContact.isEncrypted, isUpload: false, messageId: newMessageId)
    }

    func requestMAM() {
        if mamRequestInProgress { return }
        mamRequestInProgress = true

        guard let acc = xmpp.getEnabledAccount(forID: NSNumber(value: account.id)) else { return }

        let lastStanzaId = messages.last?.stanzaId // last here because list is reversed
            ?? db.lastStanzaId(forAccount: NSNumber(value: account.id))

        acc.setMAMQueryMostRecentFor(monalContact, before: lastStanzaId) { [weak self] msgs, _ in
            DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) { [weak self] in
                self?.mamRequestInProgress = false
                if !(msgs ?? []).isEmpty {
                    self?.refreshMessages()
                }
            }
        }
    }
}

private extension WrapperChat {
    func subscribe() {
        let newMsg = NotificationCenter.default.addObserver(forName: Notification.Name(kMonalNewMessageNotice), object: nil, queue: .main) { [weak self] _ in
            self?.refreshMessages()
        }
        notificationObservers.append(newMsg)

        let sentMsg = NotificationCenter.default.addObserver(forName: Notification.Name(kMonalSentMessageNotice), object: nil, queue: .main) { [weak self] _ in
            self?.refreshMessages()
        }
        notificationObservers.append(sentMsg)
    }

    func refreshMessages() {
        let messages = db.messages(forContact: contact.contactJid, forAccount: NSNumber(value: contact.ownerId))
            .compactMap { obj -> Message? in
                guard let message = obj as? MLMessage else { return nil }
                return Message(message)
            }
            .sorted { $0.timestamp > $1.timestamp }
        self.messages = messages
    }

    func toggleOmemo(_ new: Bool) {
        if monalContact.isEncrypted != new {
            monalContact.toggleEncryption(new)
        }
    }
}