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

    init?(with: Contact) {
        contact = with
        xmpp = MLXMPPManager.sharedInstance()
        db = DataLayer.sharedInstance()

        guard
            let monalContact = db.contactList()
                .first(where: {
                    $0.accountID.intValue == with.ownerId
                })
        else { return nil }
        self.monalContact = monalContact
        isOmemoEnabled = monalContact.isEncrypted

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

    init?(with: Chat) {
        xmpp = MLXMPPManager.sharedInstance()
        db = DataLayer.sharedInstance()

        guard
            let monalContact = db.contactList()
                .first(where: {
                    $0.accountID.intValue == with.accountId
                })
        else { return nil }
        self.monalContact = monalContact
        isOmemoEnabled = monalContact.isEncrypted

        guard let contact = Contact(monalContact) else { return nil }
        self.contact = contact

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

        // guard let account = accounts.first(where: { $0.id == with.accountId }) else { return nil }
        //
        // var contact = contacts.first(where: { $0.ownerId == with.accountId && $0.contactJid == with.participantJid })
        // if contact == nil {
        //     let semaphore = DispatchSemaphore(value: 0)
        //     Task {
        //         await addContact(contactJid: with.participantJid, forAccountID: with.accountId)
        //         semaphore.signal()
        //     }
        //     semaphore.wait()
        //     contact = contacts.first(where: { $0.ownerId == with.accountId && $0.contactJid == with.participantJid })
        // }
        //
        // guard let contact else { return nil }
        // let chatModel = WrapperChat(account: account, contact: contact, db: db, xmpp: xmpp)
        // return chatModel
    }

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

            // MARK: WARNING!
            actuallyFrom: "testmon3@test.anal.company",
            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() {
        guard let acc = monalContact.account else { return }
        if mamRequestInProgress { return }
        mamRequestInProgress = true

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

        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)
        }
    }
}