//
//  NetworkServiceApiWebSockets.swift
//  Wallet
//
//  Created by Saveliy Stavitsky on 1/15/21.
//  Copyright © 2021 AM. All rights reserved.
//

import Foundation
import Starscream

extension Notification.Name {
    static let socketDidConnect     = Self("Network.Service.WebSockets.socketDidConnect")
    static let socketDidUpdateValue = Self("Network.Service.WebSockets.socketDidUpdateValue")
    static let socketDidDisconnect  = Self("Network.Service.WebSockets.socketDidDisconnect")
}

extension Network.Service {
    class WebSockets: Common.Service.Provider {
        private var timer: Timer?
        private var reconectTimer: Timer?
        private var collection = [String:Subscription]()
        init() {
            timer = delayed(45, repeats: true) { self.update() }
            reconectTimer = delayed(1, repeats: true) { self.reconect() }
        }
    }
}

extension Network.Service.WebSockets {
    func open(subscription: String, id: String) {
        collection[id] = Subscription(id: id, subscription: subscription)
    }
    func contains(id: String) -> Bool {
        collection[id] != nil
    }
    func remove(id: String) {
        collection[id] = nil
    }
    func remove(idPrefix prefix: String) {
        let toRemoveIds = collection.filter({ $0.key.hasPrefix(prefix) }).map({ $0.key })
        for id in toRemoveIds {
            collection[id] = nil
        }
    }
    func remove(idSuffix suffix: String) {
        let toRemoveIds = collection.filter({ $0.key.hasSuffix(suffix) }).map({ $0.key })
        for id in toRemoveIds {
            collection[id] = nil
        }
    }
    func removeAll() {
        collection = [:]
    }
}

extension Network.Service.WebSockets {
    private func update() {
        for subscription in collection {
            if !subscription.value.socket.isConnected {
                subscription.value.socket.connect()
            } else {
                subscription.value.socket.write(ping: Data())
            }
        }
    }
    private func reconect() {
        for subscription in collection {
            if !subscription.value.socket.isConnected {
                subscription.value.socket.connect()
            }
        }
    }
}

extension Network.Service.WebSockets {
    fileprivate class Subscription {
        let socket: WebSocket
        let id: String
        let subscription: String?
        deinit { socket.disconnect() }
        init(id: String, subscription: String?) {
            self.id = id
            self.subscription = subscription
            var request = URLRequest(url: URL(string: ApplicationEnvironment.shared().current.paycash.webSocket)!)
            request.timeoutInterval = 5
            socket = WebSocket(request: request)
            socket.delegate = self
            socket.connect()
        }
    }
}

extension Network.Service.WebSockets.Subscription: WebSocketDelegate {
    func websocketDidConnect(socket: WebSocketClient) {
        if let subscription = subscription { socket.write(string: subscription) }
        Notification.post(name: .socketDidConnect, userInfo: ["id": id])
    }
    func websocketDidDisconnect(socket: WebSocketClient, error: Error?) {
        socket.connect()
        Notification.post(name: .socketDidDisconnect, userInfo: ["id": id])
    }
    func websocketDidReceiveMessage(socket: WebSocketClient, text: String) {
        Notification.post(name: .socketDidUpdateValue, userInfo: ["id": id, "data": text])
    }
    func websocketDidReceiveData(socket: WebSocketClient, data: Data) {
        Notification.post(name: .socketDidUpdateValue, userInfo: ["id": id, "data": String(data: data, encoding: .utf8) ?? ""])
    }
}