//
//  MQTTService.swift
//  QuickLocation
//
//  Created by 八条 on 2026/6/12.
//

import Foundation
import CocoaMQTT
import UIKit
import CoreLocation
import Network
import CoreTelephony
import AVFoundation

// MARK: - MQTT 模型

/// 位置上报类型
enum MqttType: String, Codable {
    case track = "track" // 追踪（获取)和更新用户状态
    case disconnect = "disconnect"
    case message = "message"
    case join = "join" // 加入群
    case leave = "leave" // 离开群
    case dismiss = "dismiss" // 解散群
    case kick = "kick" // 踢人
    case signIn = "signIn" // 签到
    case sos = "sos" // 求助
    case needTrack = "needtrack" // 追踪上报
    case emote = "emote" // 接收表情
    case phone = "phone" // 手机信息上报
    case phoneUsage = "phoneUsage" // 当前 App 使用次数上报
}

/// 单点位置
struct Points: Codable {
    let lat: Double
    let lon: Double
    let addr: String
    let time: Int64          // 毫秒时间戳
    let speed: Double
    let bearing: Double
    let altitude: Double
    let accuracy: Double
}

/// 位置上报数据（发送）
struct MqttLocation: Codable {
    let battery: String
    let points: [Points]
}

/// 签到上报数据
struct MqttSignIn: Codable {
    let topic: String?
    let latitude: Double
    let longitude: Double
    let address: String
}

/// MQTT 收到的位置消息（接收解析用）
struct MqttIncomingMessage: Decodable {
    let type: String?
    let data: MqttIncomingData?
    let extra: String?
}

struct MqttIncomingData: Decodable {
    let points: [Points]?
    let battery: String?
    let index: Int?
    let group_key: String?
    let user_id: String?
}

/// 手机信息上报数据
private struct MqttPhoneInfo: Codable {
    let brand: String
    let model: String
    let memory_total: String
    let memory_used: String
    let battery: String
    let network: String
    let brightness: String
    let volume: String
    let weather: String
    let use_time: String
    let unlock_count: String
}

private struct MqttPhoneReportData: Codable {
    let user_id: String
    let group_key: String
    let phone: MqttPhoneInfo
}

private struct MqttPhoneReportPayload: Codable {
    let type: String
    let data: MqttPhoneReportData
    let extra: String
}

private struct MqttPhoneUsageExtra: Codable {
    let count: Int
}

private struct MqttPhoneUsageItem: Codable {
    let day: String
    let appName: String
    let packageName: String
    let usageTime: Int
    let extra: MqttPhoneUsageExtra

    enum CodingKeys: String, CodingKey {
        case day
        case appName = "app_name"
        case packageName = "package"
        case usageTime = "usage_time"
        case extra
    }
}

private struct MqttPhoneUsageData: Codable {
    let userId: String
    let groupKey: String
    let phoneUsage: [MqttPhoneUsageItem]

    enum CodingKeys: String, CodingKey {
        case userId = "user_id"
        case groupKey = "group_key"
        case phoneUsage = "phone_usage"
    }
}

private struct MqttPhoneUsagePayload: Codable {
    let type: String
    let data: MqttPhoneUsageData
    let extra: String
}

private struct MqttPhoneUsageSnapshot: Equatable {
    let day: String
    let count: Int
}

// MARK: - MQTTService

/// MQTT 5.0 服务，管理连接、订阅和消息收发
final class MQTTService: NSObject {

    static let shared = MQTTService()

    private var mqtt: CocoaMQTT5?
    private var isConnected = false

    // MARK: - 连接状态回调
    var onConnected: (() -> Void)?
    var onDisconnected: (() -> Void)?

    /// 全局接收回调（所有未匹配 topicCallback 的消息）
    var onMessageReceived: ((CocoaMQTT5Message, UInt16, MqttPublishProperties) -> Void)?

    /// 按 topic 订阅的回调（优先匹配）
    private var topicCallbacks: [String: (CocoaMQTT5Message) -> Void] = [:]

    // MARK: - 配置
    private var host: String { "emqx.batiao8.com" }
    private var port: UInt16 { 1883 }
    /// 当前 clientID，切换用户时可更新后重连
    private(set) var clientID: String = ""
    private var userName = "batiao"
    private var password = "Batiao12B"
    private var topic = "smartdrive/"

    // MARK: - 手机信息上报
    private let phoneReportInterval: TimeInterval = 30 * 60
    private let phoneReportRetryInterval: TimeInterval = 60
    private let phoneNetworkMonitor = PhoneNetworkStatusMonitor()
    private var phoneReportGroupKey = ""
    private var phoneReportLocation: CLLocation?
    private var phoneReportTimer: Timer?
    private var lastPhoneReportDate: Date?
    private var isPhoneReportInFlight = false
    private var phoneReportGeneration = 0
    private var lastObservedPhoneUsage: MqttPhoneUsageSnapshot?
    private var pendingPhoneUsage: MqttPhoneUsageSnapshot?

    override private init() {
        super.init()
        UIDevice.current.isBatteryMonitoringEnabled = true
        phoneNetworkMonitor.start()
        NotificationCenter.default.addObserver(
            self,
            selector: #selector(applicationDidBecomeActive),
            name: UIApplication.didBecomeActiveNotification,
            object: nil
        )
        NotificationCenter.default.addObserver(
            self,
            selector: #selector(appUsageCountDidChange),
            name: .unlockCountDidChange,
            object: nil
        )
        let usage = Self.currentPhoneUsageSnapshot()
        lastObservedPhoneUsage = usage
        if usage.count > 0 {
            pendingPhoneUsage = usage
        }
    }

    // MARK: - 连接
    func connect() {
        guard !isConnected else { return }

        if clientID.isEmpty {
            clientID = "smartdrive_\(AppContextManager.shared.userId)"
        }
        let mqtt = CocoaMQTT5(clientID: clientID, host: host, port: port)
        mqtt.username = userName
        mqtt.password = password
        mqtt.cleanSession = true
        mqtt.keepAlive = 30
        mqtt.autoReconnect = true
        mqtt.autoReconnectTimeInterval = 5
        mqtt.delegate = self
        mqtt.logLevel = .warning
        // MQTT 5 连接属性（对应 Android 端配置）
        let connProps = MqttConnectProperties()
        connProps.sessionExpiryInterval = 30
        connProps.receiveMaximum = 10
        connProps.maximumPacketSize = 10240
        connProps.topicAliasMaximum = 0
        mqtt.connectProperties = connProps
        // Will 消息
        let will = CocoaMQTT5Message(topic: "willtopic", payload: [])
        will.qos = .qos1
        will.retained = false
        mqtt.willMessage = will

        self.mqtt = mqtt
        _ = mqtt.connect()
    }

    // MARK: - 断开
    func disconnect() {
        mqtt?.disconnect()
        isConnected = false
        invalidatePhoneReportTimer()
    }

    // MARK: - 切换用户
    /// 更新 clientID 并重连（切换用户后调用）
    func updateClientID(_ newID: String) {
        resetPhoneReportState()
        clientID = newID
        disconnect()
        connect()
    }

    // MARK: - 订阅主题
    /// - Parameters:
    ///   - topic: 主题
    ///   - qos: 服务质量
    ///   - callback: 可选，该 topic 的专用回调，收到消息时优先于此回调
    func subscribe(topic: String, qos: CocoaMQTTQoS = .qos1, callback: ((CocoaMQTT5Message) -> Void)? = nil) {
        let subscription = MqttSubscription(topic: topic, qos: qos)
        subscription.noLocal = false
        subscription.retainAsPublished = true
        subscription.retainHandling = .none
        mqtt?.subscribe([subscription])
        if let cb = callback {
            topicCallbacks[topic] = cb
        }
    }

    // MARK: - 取消订阅
    func unsubscribe(topic: String) {
        mqtt?.unsubscribe(topic)
        topicCallbacks.removeValue(forKey: topic)
    }

    /// 订阅指定圈子的所有成员位置 topic: smartdrive/<memberId>
    func subscribeGroupMembers(_ memberIds: [String]) {
        for id in memberIds {
            subscribe(topic: "\(topic)\(id)")
        }
    }

    /// 取消订阅上一批成员
    func unsubscribeGroupMembers(_ memberIds: [String]) {
        for id in memberIds {
            mqtt?.unsubscribe("\(topic)\(id)")
        }
    }

    // MARK: - 发布消息
    @discardableResult
    func publish(topic: String, message: String, qos: CocoaMQTTQoS = .qos1) -> Int {
        let properties = MqttPublishProperties()
        return mqtt?.publish(topic, withString: message, qos: qos, DUP: false, retained: false, properties: properties) ?? -1
    }

    @discardableResult
    func publish(topic: String, data: Data, qos: CocoaMQTTQoS = .qos1) -> Int {
        let properties = MqttPublishProperties()
        let message = CocoaMQTT5Message(topic: topic, payload: [UInt8](data))
        return mqtt?.publish(message, DUP: false, retained: false, properties: properties) ?? -1
    }

    // MARK: - 位置上报
    /// 构建并上报位置数据（格式与 Android 一致）
    func reportLocation(lat: Double, lon: Double, addr: String,
                        speed: CLLocationSpeed, bearing: CLLocationDirection,
                        altitude: CLLocationDistance, accuracy: CLLocationAccuracy) {
        let battery = UIDevice.current.batteryLevel > 0
            ? Int(UIDevice.current.batteryLevel * 100)
            : 0

        let point = Points(
            lat: lat, lon: lon, addr: addr,
            time: Int64(Date().timeIntervalSince1970 * 1000),
            speed: speed, bearing: bearing,
            altitude: altitude, accuracy: accuracy
        )
        let location = MqttLocation(battery: battery.string, points: [point])

        guard let jsonData = try? JSONEncoder().encode(location),
              let dataDict = try? JSONSerialization.jsonObject(with: jsonData) as? [String: Any]
        else { return }

        // 外层包装，data 是 JSON 对象而非字符串
        let payload: [String: Any] = [
            "type": MqttType.track.rawValue,
            "extra": "",
            "data": dataDict
        ]
        
        publish(topic: "\(topic)\(AppContextManager.shared.userId)", message: payload.toJsonString())
    }
    
    // MARK: - 签到
    func reportSignIn(lat: Double, lon: Double, addr: String) {
        let signIn = MqttSignIn(topic: nil, latitude: lat, longitude: lon, address: addr)
        guard let jsonData = try? JSONEncoder().encode(signIn),
              let dataDict = try? JSONSerialization.jsonObject(with: jsonData) as? [String: Any]
        else { return }

        let payload: [String: Any] = [
            "type": MqttType.signIn.rawValue,
            "data": dataDict,
            "extra": "",
            "sort": ""
        ]
        publish(topic: "\(topic)\(AppContextManager.shared.userId)", message: payload.toJsonString())
    }

    // MARK: - 手机信息上报

    /// 首页提供当前默认圈子和最新定位。切换圈子只更新上下文，不额外触发重复上报。
    func updatePhoneReportContext(groupKey: String?, location: CLLocation?) {
        performOnMain { [weak self] in
            guard let self else { return }
            if let groupKey {
                self.phoneReportGroupKey = groupKey
            }
            if let location, CLLocationCoordinate2DIsValid(location.coordinate) {
                self.phoneReportLocation = location
            }
            self.reportPhoneUsageIfNeeded()
            self.reportPhoneIfNeeded()
        }
    }

    /// MQTT 重连、Timer 和 App 回到前台都通过此入口检查是否到期。
    func reportPhoneIfNeeded(force: Bool = false) {
        guard Thread.isMainThread else {
            DispatchQueue.main.async { [weak self] in
                self?.reportPhoneIfNeeded(force: force)
            }
            return
        }

        guard isConnected,
              !isPhoneReportInFlight,
              !phoneReportGroupKey.isEmpty,
              !AppContextManager.shared.userId.isEmpty else { return }

        if !force,
           let lastPhoneReportDate,
           Date().timeIntervalSince(lastPhoneReportDate) < phoneReportInterval {
            schedulePhoneReportTimer(after: phoneReportInterval - Date().timeIntervalSince(lastPhoneReportDate))
            return
        }

        isPhoneReportInFlight = true
        phoneReportGeneration += 1
        let generation = phoneReportGeneration

        guard let location = phoneReportLocation else {
            finishPhoneReport(weather: "未知", generation: generation)
            return
        }

        MemberWeatherService.shared.weather(for: location) { [weak self] result in
            let weather = (try? result.get().text) ?? "未知"
            self?.finishPhoneReport(weather: weather, generation: generation)
        }
    }

    @objc func applicationDidBecomeActive() {
        capturePhoneUsageChange()
        reportPhoneUsageIfNeeded()
        reportPhoneIfNeeded()
    }

    @objc private func appUsageCountDidChange() {
        performOnMain { [weak self] in
            self?.capturePhoneUsageChange()
        }
    }

    private func capturePhoneUsageChange() {
        let usage = Self.currentPhoneUsageSnapshot()
        guard usage != lastObservedPhoneUsage else { return }
        lastObservedPhoneUsage = usage
        pendingPhoneUsage = usage
        reportPhoneUsageIfNeeded()
    }

    private func reportPhoneUsageIfNeeded() {
        guard Thread.isMainThread else {
            DispatchQueue.main.async { [weak self] in
                self?.reportPhoneUsageIfNeeded()
            }
            return
        }

        let userId = AppContextManager.shared.userId
        let groupKey = phoneReportGroupKey
        guard isConnected,
              let usage = pendingPhoneUsage,
              !userId.isEmpty,
              !groupKey.isEmpty else { return }

        let item = MqttPhoneUsageItem(
            day: usage.day,
            appName: Self.appDisplayName,
            packageName: "cn.zuom8.jisuloca",
            usageTime: 0,
            extra: MqttPhoneUsageExtra(count: usage.count)
        )
        let payload = MqttPhoneUsagePayload(
            type: MqttType.phoneUsage.rawValue,
            data: MqttPhoneUsageData(
                userId: userId,
                groupKey: groupKey,
                phoneUsage: [item]
            ),
            extra: ""
        )
        guard let data = try? JSONEncoder().encode(payload),
              let message = String(data: data, encoding: .utf8) else { return }

        let messageId = publish(
            topic: "\(topic)\(userId)",
            message: message
        )
        if messageId >= 0, pendingPhoneUsage == usage {
            pendingPhoneUsage = nil
        }
    }

    private func finishPhoneReport(weather: String, generation: Int) {
        performOnMain { [weak self] in
            guard let self,
                  generation == self.phoneReportGeneration else { return }
            self.isPhoneReportInFlight = false

            let userId = AppContextManager.shared.userId
            let groupKey = self.phoneReportGroupKey
            guard self.isConnected, !userId.isEmpty, !groupKey.isEmpty else { return }

            let payload = MqttPhoneReportPayload(
                type: MqttType.phone.rawValue,
                data: MqttPhoneReportData(
                    user_id: userId,
                    group_key: groupKey,
                    phone: self.collectPhoneInfo(weather: weather)
                ),
                extra: ""
            )
            guard let data = try? JSONEncoder().encode(payload),
                  let message = String(data: data, encoding: .utf8) else {
                self.schedulePhoneReportTimer(after: self.phoneReportRetryInterval)
                return
            }

            let messageId = self.publish(
                topic: "\(self.topic)\(userId)",
                message: message
            )
            if messageId >= 0 {
                self.lastPhoneReportDate = Date()
                self.schedulePhoneReportTimer(after: self.phoneReportInterval)
            } else {
                self.schedulePhoneReportTimer(after: self.phoneReportRetryInterval)
            }
        }
    }

    private func collectPhoneInfo(weather: String) -> MqttPhoneInfo {
        let storage = Self.storageInfo()
        return MqttPhoneInfo(
            brand: "iphone",
            model: UIDevice.modelName,
            memory_total: storage?.total ?? "未知",
            memory_used: storage?.used ?? "未知",
            battery: UIDevice.batteryPercent.map { "\($0)%" } ?? "未知",
            network: phoneNetworkMonitor.statusText,
            brightness: "\(Int((UIScreen.main.brightness * 100).rounded()))%",
            volume: "\(Int((AVAudioSession.sharedInstance().outputVolume * 100).rounded()))%",
            weather: weather,
            use_time: "\(max(0, UnlockCountManager.shared.todayScreenTimeSeconds))",
            unlock_count: "\(UnlockCountManager.shared.todayCount)"
        )
    }

    private func schedulePhoneReportTimer(after interval: TimeInterval) {
        invalidatePhoneReportTimer()
        let timer = Timer(timeInterval: max(1, interval), repeats: false) { [weak self] _ in
            self?.phoneReportTimer = nil
            self?.reportPhoneIfNeeded()
        }
        RunLoop.main.add(timer, forMode: .common)
        phoneReportTimer = timer
    }

    private func invalidatePhoneReportTimer() {
        performOnMain { [weak self] in
            self?.phoneReportTimer?.invalidate()
            self?.phoneReportTimer = nil
        }
    }

    private func resetPhoneReportState() {
        performOnMain { [weak self] in
            guard let self else { return }
            self.phoneReportGeneration += 1
            self.phoneReportGroupKey = ""
            self.phoneReportLocation = nil
            self.lastPhoneReportDate = nil
            self.isPhoneReportInFlight = false
            self.invalidatePhoneReportTimer()
        }
    }

    private func performOnMain(_ work: @escaping () -> Void) {
        if Thread.isMainThread {
            work()
        } else {
            DispatchQueue.main.async(execute: work)
        }
    }

    private static func storageInfo() -> (used: String, total: String)? {
        let url = URL(fileURLWithPath: NSHomeDirectory())
        let keys: Set<URLResourceKey> = [
            .volumeTotalCapacityKey,
            .volumeAvailableCapacityForImportantUsageKey
        ]
        guard let values = try? url.resourceValues(forKeys: keys),
              let total = values.volumeTotalCapacity,
              let available = values.volumeAvailableCapacityForImportantUsage,
              total > 0 else { return nil }

        let totalBytes = Int64(total)
        let usedBytes = max(0, totalBytes - available)
        return (
            used: String(format: "%.1fGB", Double(usedBytes) / 1_000_000_000),
            total: String(format: "%.0fGB", Double(totalBytes) / 1_000_000_000)
        )
    }

    private static func currentPhoneUsageSnapshot() -> MqttPhoneUsageSnapshot {
        let formatter = DateFormatter()
        formatter.calendar = Calendar.current
        formatter.locale = Locale(identifier: "en_US_POSIX")
        formatter.timeZone = TimeZone.current
        formatter.dateFormat = "yyyy-MM-dd"
        return MqttPhoneUsageSnapshot(
            day: formatter.string(from: Date()),
            count: max(0, UnlockCountManager.shared.todayAppUsageCount)
        )
    }

    private static var appDisplayName: String {
        Bundle.main.object(forInfoDictionaryKey: "CFBundleDisplayName") as? String
            ?? Bundle.main.object(forInfoDictionaryKey: "CFBundleName") as? String
            ?? "极速定位"
    }

}

// MARK: - CocoaMQTT5Delegate
extension MQTTService: CocoaMQTT5Delegate {

    func mqtt5(_ mqtt5: CocoaMQTT5, didConnectAck ack: CocoaMQTTCONNACKReasonCode, connAckData: MqttDecodeConnAck?) {
        isConnected = true
        print("MQTT5 connected: \(ack)")
        // 订阅基础 topic，接收 signIn/join/leave 等非位置消息
        subscribe(topic: topic)
        onConnected?()
        reportPhoneUsageIfNeeded()
        reportPhoneIfNeeded()
    }

    func mqtt5(_ mqtt5: CocoaMQTT5, didPublishMessage message: CocoaMQTT5Message, id: UInt16) {
        print("MQTT5 published: \(message.topic)")
    }

    func mqtt5(_ mqtt5: CocoaMQTT5, didPublishAck id: UInt16, pubAckData: MqttDecodePubAck?) {
        print("MQTT5 publish ack: \(id)")
    }

    func mqtt5(_ mqtt5: CocoaMQTT5, didPublishRec id: UInt16, pubRecData: MqttDecodePubRec?) {}

    func mqtt5(_ mqtt5: CocoaMQTT5, didReceiveMessage message: CocoaMQTT5Message, id: UInt16, publishData: MqttDecodePublish?) {
        // 优先 topic 专用回调
        if let cb = topicCallbacks[message.topic] {
            cb(message)
            return
        }
        // 没有专用回调时走全局回调
        if let payload = message.string {
            print("MQTT5 received on \(message.topic): \(payload)")
        }
        onMessageReceived?(message, id, MqttPublishProperties())
    }

    func mqtt5(_ mqtt5: CocoaMQTT5, didSubscribeTopics success: NSDictionary, failed: [String], subAckData: MqttDecodeSubAck?) {
        print("MQTT5 subscribe success: \(success), failed: \(failed)")
    }

    func mqtt5(_ mqtt5: CocoaMQTT5, didUnsubscribeTopics topics: [String], unsubAckData: MqttDecodeUnsubAck?) {
        print("MQTT5 unsubscribe: \(topics)")
    }

    func mqtt5(_ mqtt5: CocoaMQTT5, didReceiveDisconnectReasonCode reasonCode: CocoaMQTTDISCONNECTReasonCode) {}

    func mqtt5(_ mqtt5: CocoaMQTT5, didReceiveAuthReasonCode reasonCode: CocoaMQTTAUTHReasonCode) {}

    func mqtt5DidPing(_ mqtt5: CocoaMQTT5) {}

    func mqtt5DidReceivePong(_ mqtt5: CocoaMQTT5) {}

    func mqtt5DidDisconnect(_ mqtt5: CocoaMQTT5, withError err: Error?) {
        isConnected = false
        invalidatePhoneReportTimer()
        print("MQTT5 disconnected: \(err?.localizedDescription ?? "")")
        onDisconnected?()
    }
}

private final class PhoneNetworkStatusMonitor {

    private let monitor = NWPathMonitor()
    private let queue = DispatchQueue(label: "com.quicklocation.mqtt.network")
    private let lock = NSLock()
    private let telephonyInfo = CTTelephonyNetworkInfo()
    private var path: NWPath?

    func start() {
        monitor.pathUpdateHandler = { [weak self] path in
            self?.lock.lock()
            self?.path = path
            self?.lock.unlock()
        }
        monitor.start(queue: queue)
    }

    var statusText: String {
        lock.lock()
        let currentPath = path
        lock.unlock()

        guard let currentPath, currentPath.status == .satisfied else {
            return "无网络"
        }
        if currentPath.usesInterfaceType(.wifi) {
            return "Wi-Fi"
        }
        guard currentPath.usesInterfaceType(.cellular) else {
            return "无网络"
        }
        return cellularGeneration
    }

    private var cellularGeneration: String {
        let technologies = telephonyInfo.serviceCurrentRadioAccessTechnology
            .map { Array($0.values) } ?? []
        guard let technology = technologies.first else { return "蜂窝" }
        switch technology {
        case CTRadioAccessTechnologyNR, CTRadioAccessTechnologyNRNSA:
            return "5G"
        case CTRadioAccessTechnologyLTE:
            return "4G"
        case CTRadioAccessTechnologyWCDMA,
             CTRadioAccessTechnologyHSDPA,
             CTRadioAccessTechnologyHSUPA,
             CTRadioAccessTechnologyCDMAEVDORev0,
             CTRadioAccessTechnologyCDMAEVDORevA,
             CTRadioAccessTechnologyCDMAEVDORevB,
             CTRadioAccessTechnologyeHRPD:
            return "3G"
        case CTRadioAccessTechnologyGPRS,
             CTRadioAccessTechnologyEdge,
             CTRadioAccessTechnologyCDMA1x:
            return "2G"
        default:
            return "蜂窝"
        }
    }
}