import Foundation
import Postbox
import SwiftSignalKit
import TelegramApi

public enum ServerProvidedSuggestion: Hashable {
    case autoarchivePopular
    case newcomerTicks
    case validatePhoneNumber
    case validatePassword
    case setupPassword
    case upgradePremium
    case annualPremium
    case restorePremium
    case xmasPremiumGift
    case setupBirthday
    case todayBirthdays
    case gracePremium
    case starsSubscriptionLowBalance
    case setupPhoto
    case link(url: String, title: String, subtitle: String)
    
    public init?(string: String) {
        switch string {
        case "AUTOARCHIVE_POPULAR":
            self = .autoarchivePopular
        case "NEWCOMER_TICKS":
            self = .newcomerTicks
        case "VALIDATE_PHONE_NUMBER":
            self = .validatePhoneNumber
        case "VALIDATE_PASSWORD":
            self = .validatePassword
        case "SETUP_PASSWORD":
            self = .setupPassword
        case "PREMIUM_UPGRADE":
            self = .upgradePremium
        case "PREMIUM_ANNUAL":
            self = .annualPremium
        case "PREMIUM_RESTORE":
            self = .restorePremium
        case "PREMIUM_CHRISTMAS":
            self = .xmasPremiumGift
        case "BIRTHDAY_SETUP":
            self = .setupBirthday
        case "BIRTHDAY_CONTACTS_TODAY":
            self = .todayBirthdays
        case "PREMIUM_GRACE":
            self = .gracePremium
        case "STARS_SUBSCRIPTION_LOW_BALANCE":
            self = .starsSubscriptionLowBalance
        case "USERPIC_SETUP":
            self = .setupPhoto
        default:
            if string.hasPrefix("LINK_") {
                let rawString = string.dropFirst(Int("LINK_".count))
                if let dict = try? JSONSerialization.jsonObject(with: rawString.data(using: .utf8) ?? Data()) as? [String: Any] {
                    var url: String?
                    var title: String?
                    var subtitle: String?

                    if let urlValue = dict["url"] as? String {
                        url = urlValue
                    }
                    if let titleValue = dict["title"] as? String {
                        title = titleValue
                    }
                    if let subtitleValue = dict["subtitle"] as? String {
                        subtitle = subtitleValue
                    }
                    if let url = url, let title = title, let subtitle = subtitle {
                        self = .link(url: url, title: title, subtitle: subtitle)
                        return
                    }
                }
            }
            return nil
        }
    }

    var stringValue: String {
        switch self {
        case .autoarchivePopular:
            return "AUTOARCHIVE_POPULAR"
        case .newcomerTicks:
            return "NEWCOMER_TICKS"
        case .validatePhoneNumber:
            return "VALIDATE_PHONE_NUMBER"
        case .validatePassword:
            return "VALIDATE_PASSWORD"
        case .setupPassword:
            return "SETUP_PASSWORD"
        case .upgradePremium:
            return "PREMIUM_UPGRADE"
        case .annualPremium:
            return "PREMIUM_ANNUAL"
        case .restorePremium:
            return "PREMIUM_RESTORE"
        case .xmasPremiumGift:
            return "PREMIUM_CHRISTMAS"
        case .setupBirthday:
            return "BIRTHDAY_SETUP"
        case .todayBirthdays:
            return "BIRTHDAY_CONTACTS_TODAY"
        case .gracePremium:
            return "PREMIUM_GRACE"
        case .starsSubscriptionLowBalance:
            return "STARS_SUBSCRIPTION_LOW_BALANCE"
        case .setupPhoto:
            return "USERPIC_SETUP"
        case let .link(url, title, subtitle):
            let dict: [String: String] = [
                "url": url,
                "title": title,
                "subtitle": subtitle
            ]
            if let data = try? JSONSerialization.data(withJSONObject: dict, options: []), let string = String(data: data, encoding: .utf8) {
                return "LINK_\(string)"
            } else {
                // Fallback or error handling, though unlikely to fail with basic strings
                return "LINK_{}" 
            }
        }
    }
}

private var dismissedSuggestionsPromise = ValuePromise<[AccountRecordId: Set<ServerProvidedSuggestion>]>([:])
private var dismissedSuggestions: [AccountRecordId: Set<ServerProvidedSuggestion>] = [:] {
    didSet {
        dismissedSuggestionsPromise.set(dismissedSuggestions)
    }
}

func _internal_getServerProvidedSuggestions(account: Account) -> Signal<[ServerProvidedSuggestion], NoError> {
    let key: PostboxViewKey = .preferences(keys: Set([PreferencesKeys.appConfiguration]))
    return combineLatest(account.postbox.combinedView(keys: [key]), dismissedSuggestionsPromise.get())
    |> map { views, dismissedSuggestionsValue -> [ServerProvidedSuggestion] in
        let dismissedSuggestions = dismissedSuggestionsValue[account.id] ?? Set()
        guard let view = views.views[key] as? PreferencesView else {
            return []
        }
        guard let appConfiguration = view.values[PreferencesKeys.appConfiguration]?.get(AppConfiguration.self) else {
            return []
        }

        #if DEBUG
        guard let data = appConfiguration.data, var listItems = data["pending_suggestions"] as? [String] else {
            return []
        }
        listItems.insert("LINK_{\"url\": \"https://t.me/durov\", \"title\": \"📣 Stay updated!\", \"subtitle\": \"Subscribe to the channel of Telegram's founder.\"}", at: 0)
        #else
        guard let data = appConfiguration.data, let listItems = data["pending_suggestions"] as? [String] else {
            return []
        }
        #endif

        return listItems.compactMap { item -> ServerProvidedSuggestion? in
            return ServerProvidedSuggestion(string: item)
        }.filter { !dismissedSuggestions.contains($0) }
    }
    |> distinctUntilChanged
}

func _internal_getServerDismissedSuggestions(account: Account) -> Signal<[ServerProvidedSuggestion], NoError> {
    let key: PostboxViewKey = .preferences(keys: Set([PreferencesKeys.appConfiguration]))
    return combineLatest(account.postbox.combinedView(keys: [key]), dismissedSuggestionsPromise.get())
    |> map { views, dismissedSuggestionsValue -> [ServerProvidedSuggestion] in
        let dismissedSuggestions = dismissedSuggestionsValue[account.id] ?? Set()
        guard let view = views.views[key] as? PreferencesView else {
            return []
        }
        guard let appConfiguration = view.values[PreferencesKeys.appConfiguration]?.get(AppConfiguration.self) else {
            return []
        }
        var listItems: [String] = []
        if let data = appConfiguration.data, let listItemsValues = data["dismissed_suggestions"] as? [String] {
            listItems.append(contentsOf: listItemsValues)
        }
        var items = listItems.compactMap { item -> ServerProvidedSuggestion? in
            return ServerProvidedSuggestion(string: item)
        }
        items.append(contentsOf: dismissedSuggestions)
        return items
    }
    |> distinctUntilChanged
}

func _internal_dismissServerProvidedSuggestion(account: Account, suggestion: ServerProvidedSuggestion) -> Signal<Never, NoError> {
    if let _ = dismissedSuggestions[account.id] {
        dismissedSuggestions[account.id]?.insert(suggestion)
    } else {
        dismissedSuggestions[account.id] = Set([suggestion])
    }
    return account.network.request(Api.functions.help.dismissSuggestion(peer: .inputPeerEmpty, suggestion: suggestion.stringValue))
    |> `catch` { _ -> Signal<Api.Bool, NoError> in
        return .single(.boolFalse)
    }
    |> ignoreValues
}


public enum PeerSpecificServerProvidedSuggestion: String {
    case convertToGigagroup = "CONVERT_GIGAGROUP"
}

func _internal_getPeerSpecificServerProvidedSuggestions(postbox: Postbox, peerId: PeerId) -> Signal<[PeerSpecificServerProvidedSuggestion], NoError> {
    return postbox.peerView(id: peerId)
    |> map { view in
        if let cachedData = view.cachedData as? CachedChannelData {
            return cachedData.pendingSuggestions.compactMap { item -> PeerSpecificServerProvidedSuggestion? in
                return PeerSpecificServerProvidedSuggestion(rawValue: item)
            }
        }
        return []
    }
    |> distinctUntilChanged
}

func _internal_dismissPeerSpecificServerProvidedSuggestion(account: Account, peerId: PeerId, suggestion: PeerSpecificServerProvidedSuggestion) -> Signal<Never, NoError> {
    return account.postbox.loadedPeerWithId(peerId)
    |> mapToSignal { peer -> Signal<Never, NoError> in
        guard let inputPeer = apiInputPeer(peer) else {
            return .never()
        }
        return account.network.request(Api.functions.help.dismissSuggestion(peer: inputPeer, suggestion: suggestion.rawValue))
        |> `catch` { _ -> Signal<Api.Bool, NoError> in
            return .single(.boolFalse)
        }
        |> mapToSignal { a -> Signal<Never, NoError> in
            return account.postbox.transaction { transaction in
                transaction.updatePeerCachedData(peerIds: [peerId]) { (_, current) -> CachedPeerData? in
                    var updated = current
                    if let cachedData = current as? CachedChannelData {
                        var pendingSuggestions = cachedData.pendingSuggestions
                        pendingSuggestions.removeAll(where: { $0 == suggestion.rawValue })
                        updated = cachedData.withUpdatedPendingSuggestions(pendingSuggestions)
                    }
                    return updated
                }
            } |> ignoreValues
        }
    }
}