import Foundation
import UIKit
import Contacts
import EventKit
import CoreLocation
import MediaPlayer
import AVFoundation

/// 操作结果
public struct Result {
    let success: Bool
    let message: String
    
    public init(success: Bool, message: String) {
        self.success = success
        self.message = message
    }
}

/// 系统功能处理器 - 负责调用系统API执行各种功能以及注册系统功能
public class SystemFunctionHandler: NSObject {
    private let tag = "SystemFunctionHandler"
    
    // 位置管理器
    private var locationManager: CLLocationManager?
    private var locationCompletion: ((Result) -> Void)?
    
    // 事件存储
    private var eventStore: EKEventStore?
    
    public override init() {
        super.init()
        setupLocationManager()
        setupEventStore()
    }
    
    /// 设置位置管理器
    private func setupLocationManager() {
        locationManager = CLLocationManager()
        locationManager?.delegate = self
        locationManager?.desiredAccuracy = kCLLocationAccuracyBest
    }
    
    /// 设置事件存储
    private func setupEventStore() {
        eventStore = EKEventStore()
    }
    
    /// 在MCPClient中注册所有系统功能
    /// - Parameter client: MCPClient实例
    public func registerAllFunctions(client: MCPClient) {
        do {
            // 注册退出交互函数
            registerExitInteractionFunction(client: client)
            
            // 注册翻译模式函数
            registerTranslationModeFunction(client: client)
            
            // 注册发送短信函数
            registerSendTextMessageFunction(client: client)
            
            // 注册拨打电话函数
            registerMakePhoneCallFunction(client: client)
            
            // 注册设置提醒函数
            registerSetReminderFunction(client: client)
            
            // 注册获取当前时间函数
            registerGetCurrentTimeFunction(client: client)
            
            // 注册获取当前位置函数
            registerGetCurrentLocationFunction(client: client)
            
            // 注册媒体控制函数
            registerMediaPlayFunction(client: client)
            registerMediaPauseFunction(client: client)
            registerMediaPreviousFunction(client: client)
            registerMediaNextFunction(client: client)
            
            // 注册打开录音机功能
            registerOpenRecorderFunction(client: client)
            
            print("\(tag) 所有系统功能注册完成")
        } catch {
            print("\(tag) 注册系统功能失败: \(error.localizedDescription)")
        }
    }
    
    // MARK: - 函数注册
    
    /// 注册退出交互函数
    private func registerExitInteractionFunction(client: MCPClient) {
        let parameters: [String: Any] = [
            "type": "object",
            "properties": [:],
            "required": []
        ]
        
        let handler = ExitInteractionHandler()
        _ = client.registerLocalFunction(
            name: "exit_interaction",
            description: "结束当前交互",
            parameters: parameters,
            handler: handler
        )
        print("\(tag) 已注册退出交互功能")
    }
    
    /// 注册翻译模式函数
    private func registerTranslationModeFunction(client: MCPClient) {
        let parameters: [String: Any] = [
            "type": "object",
            "properties": [:],
            "required": []
        ]
        
        let handler = TranslationModeHandler()
        _ = client.registerLocalFunction(
            name: "enter_translation_mode",
            description: "用户请求进入实时翻译模式时，启动实时翻译功能",
            parameters: parameters,
            handler: handler
        )
        print("\(tag) 已注册翻译模式功能")
    }
    
    /// 注册发送短信函数
    private func registerSendTextMessageFunction(client: MCPClient) {
        let parameters: [String: Any] = [
            "type": "object",
            "properties": [
                "contact": [
                    "type": "string",
                    "description": "联系人姓名或电话号码"
                ],
                "message": [
                    "type": "string",
                    "description": "短信内容"
                ]
            ],
            "required": ["contact", "message"]
        ]
        
        let handler = SendTextMessageHandler()
        _ = client.registerLocalFunction(
            name: "send_text_message",
            description: "发送短信",
            parameters: parameters,
            handler: handler
        )
        print("\(tag) 已注册发送短信功能")
    }
    
    /// 注册拨打电话函数
    private func registerMakePhoneCallFunction(client: MCPClient) {
        let parameters: [String: Any] = [
            "type": "object",
            "properties": [
                "contact": [
                    "type": "string",
                    "description": "联系人姓名或电话号码"
                ]
            ],
            "required": ["contact"]
        ]
        
        let handler = MakePhoneCallHandler()
        _ = client.registerLocalFunction(
            name: "make_phone_call",
            description: "拨打电话",
            parameters: parameters,
            handler: handler
        )
        print("\(tag) 已注册拨打电话功能")
    }
    
    /// 注册设置提醒函数
    private func registerSetReminderFunction(client: MCPClient) {
        let parameters: [String: Any] = [
            "type": "object",
            "properties": [
                "title": [
                    "type": "string",
                    "description": "提醒标题"
                ],
                "content": [
                    "type": "string",
                    "description": "提醒内容"
                ],
                "time": [
                    "type": "string",
                    "description": "提醒时间，格式为'yyyy-MM-dd HH:mm'，如'2023-12-31 14:30'"
                ]
            ],
            "required": ["title", "time"]
        ]
        
        let handler = SetReminderHandler(eventStore: eventStore)
        _ = client.registerLocalFunction(
            name: "set_reminder",
            description: "设置提醒事项",
            parameters: parameters,
            handler: handler
        )
        print("\(tag) 已注册设置提醒功能")
    }
    
    /// 注册获取当前时间函数
    private func registerGetCurrentTimeFunction(client: MCPClient) {
        let parameters: [String: Any] = [
            "type": "object",
            "properties": [
                "format": [
                    "type": "string",
                    "description": "时间格式，可选，默认为标准格式"
                ]
            ],
            "required": []
        ]
        
        let handler = GetCurrentTimeHandler()
        _ = client.registerLocalFunction(
            name: "get_current_time",
            description: "获取当前日期和时间",
            parameters: parameters,
            handler: handler
        )
        print("\(tag) 已注册获取当前时间功能")
    }
    
    /// 注册获取当前位置函数
    private func registerGetCurrentLocationFunction(client: MCPClient) {
        let parameters: [String: Any] = [
            "type": "object",
            "properties": [:],
            "required": []
        ]
        
        let handler = GetCurrentLocationHandler(systemHandler: self)
        _ = client.registerLocalFunction(
            name: "get_current_location",
            description: "获取当前地理位置",
            parameters: parameters,
            handler: handler
        )
        print("\(tag) 已注册获取当前位置功能")
    }
    
    /// 注册媒体播放功能
    private func registerMediaPlayFunction(client: MCPClient) {
        let parameters: [String: Any] = [
            "type": "object",
            "properties": [:],
            "required": []
        ]
        
        let handler = MediaPlayHandler()
        _ = client.registerLocalFunction(
            name: "media_play",
            description: "播放媒体",
            parameters: parameters,
            handler: handler
        )
        print("\(tag) 已注册媒体播放功能")
    }
    
    /// 注册媒体暂停功能
    private func registerMediaPauseFunction(client: MCPClient) {
        let parameters: [String: Any] = [
            "type": "object",
            "properties": [:],
            "required": []
        ]
        
        let handler = MediaPauseHandler()
        _ = client.registerLocalFunction(
            name: "media_pause",
            description: "暂停媒体播放",
            parameters: parameters,
            handler: handler
        )
        print("\(tag) 已注册媒体暂停功能")
    }
    
    /// 注册媒体上一首功能
    private func registerMediaPreviousFunction(client: MCPClient) {
        let parameters: [String: Any] = [
            "type": "object",
            "properties": [:],
            "required": []
        ]
        
        let handler = MediaPreviousHandler()
        _ = client.registerLocalFunction(
            name: "media_previous",
            description: "播放上一首",
            parameters: parameters,
            handler: handler
        )
        print("\(tag) 已注册媒体上一首功能")
    }
    
    /// 注册媒体下一首功能
    private func registerMediaNextFunction(client: MCPClient) {
        let parameters: [String: Any] = [
            "type": "object",
            "properties": [:],
            "required": []
        ]
        
        let handler = MediaNextHandler()
        _ = client.registerLocalFunction(
            name: "media_next",
            description: "播放下一首",
            parameters: parameters,
            handler: handler
        )
        print("\(tag) 已注册媒体下一首功能")
    }
    
    /// 注册打开录音机功能
    private func registerOpenRecorderFunction(client: MCPClient) {
        let parameters: [String: Any] = [
            "type": "object",
            "properties": [:],
            "required": []
        ]
        
        let handler = OpenRecorderHandler()
        _ = client.registerLocalFunction(
            name: "open_recorder",
            description: "打开系统录音机并开始录音",
            parameters: parameters,
            handler: handler
        )
        print("\(tag) 已注册打开录音机功能")
    }
    
    // MARK: - 内部方法
    
    /// 获取当前位置
    internal func getCurrentLocation() async -> Result {
        return await withCheckedContinuation { continuation in
            locationCompletion = { result in
                continuation.resume(returning: result)
            }
            
            guard let locationManager = locationManager else {
                continuation.resume(returning: Result(success: false, message: "位置管理器未初始化"))
                return
            }
            
            // 检查位置权限
            let authStatus = locationManager.authorizationStatus
            switch authStatus {
            case .notDetermined:
                locationManager.requestWhenInUseAuthorization()
                return
            case .denied, .restricted:
                continuation.resume(returning: Result(success: false, message: "位置权限被拒绝"))
                return
            case .authorizedWhenInUse, .authorizedAlways:
                break
            @unknown default:
                continuation.resume(returning: Result(success: false, message: "未知的位置权限状态"))
                return
            }
            
            // 检查位置服务是否可用
            guard CLLocationManager.locationServicesEnabled() else {
                continuation.resume(returning: Result(success: false, message: "位置服务未启用"))
                return
            }
            
            // 请求位置
            locationManager.requestLocation()
        }
    }
}

// MARK: - CLLocationManagerDelegate
extension SystemFunctionHandler: CLLocationManagerDelegate {
    public func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        guard let location = locations.last else {
            locationCompletion?(Result(success: false, message: "无法获取位置信息"))
            return
        }
        
        let latitude = location.coordinate.latitude
        let longitude = location.coordinate.longitude
        let message = "当前位置：纬度 \(latitude)，经度 \(longitude)"
        
        locationCompletion?(Result(success: true, message: message))
        locationCompletion = nil
    }
    
    public func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
        locationCompletion?(Result(success: false, message: "获取位置失败：\(error.localizedDescription)"))
        locationCompletion = nil
    }
    
    public func locationManager(_ manager: CLLocationManager, didChangeAuthorization status: CLAuthorizationStatus) {
        if status == .authorizedWhenInUse || status == .authorizedAlways {
            manager.requestLocation()
        } else if status == .denied || status == .restricted {
            locationCompletion?(Result(success: false, message: "位置权限被拒绝"))
            locationCompletion = nil
        }
    }
}

// MARK: - 功能处理器实现

/// 退出交互处理器
private class ExitInteractionHandler: FunctionHandler {
    func handle(arguments: [String: Any]) async throws -> String {
        // 发送退出交互通知
        NotificationCenter.default.post(name: NSNotification.Name("ExitInteraction"), object: nil)
        return "{\"result\": \"已结束当前交互\"}"
    }
}

/// 翻译模式处理器
private class TranslationModeHandler: FunctionHandler {
    func handle(arguments: [String: Any]) async throws -> String {
        // 发送进入翻译模式通知
        NotificationCenter.default.post(name: NSNotification.Name("EnterTranslationMode"), object: nil)
        return "{\"result\": \"已进入翻译模式\"}"
    }
}

/// 发送短信处理器
private class SendTextMessageHandler: FunctionHandler {
    func handle(arguments: [String: Any]) async throws -> String {
        guard let contact = arguments["contact"] as? String,
              let message = arguments["message"] as? String else {
            throw OpenAIException("缺少必要参数")
        }
        
        let result = await sendTextMessage(contact: contact, message: message)
        return "{\"result\": \"\(result.message)\"}"
    }
    
    private func sendTextMessage(contact: String, message: String) async -> Result {
        // 在iOS中，我们只能打开短信应用，无法直接发送短信
        guard let url = URL(string: "sms:\(contact)&body=\(message.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed) ?? "")") else {
            return Result(success: false, message: "无法创建短信URL")
        }
        
        return await withCheckedContinuation { continuation in
            DispatchQueue.main.async {
                if UIApplication.shared.canOpenURL(url) {
                    UIApplication.shared.open(url) { success in
                        if success {
                            continuation.resume(returning: Result(success: true, message: "已打开短信应用"))
                        } else {
                            continuation.resume(returning: Result(success: false, message: "打开短信应用失败"))
                        }
                    }
                } else {
                    continuation.resume(returning: Result(success: false, message: "无法打开短信应用"))
                }
            }
        }
    }
}

/// 拨打电话处理器
private class MakePhoneCallHandler: FunctionHandler {
    func handle(arguments: [String: Any]) async throws -> String {
        guard let contact = arguments["contact"] as? String else {
            throw OpenAIException("缺少联系人参数")
        }
        
        let result = await makePhoneCall(contact: contact)
        return "{\"result\": \"\(result.message)\"}"
    }
    
    private func makePhoneCall(contact: String) async -> Result {
        guard let url = URL(string: "tel:\(contact)") else {
            return Result(success: false, message: "无法创建电话URL")
        }
        
        return await withCheckedContinuation { continuation in
            DispatchQueue.main.async {
                if UIApplication.shared.canOpenURL(url) {
                    UIApplication.shared.open(url) { success in
                        if success {
                            continuation.resume(returning: Result(success: true, message: "已发起电话呼叫"))
                        } else {
                            continuation.resume(returning: Result(success: false, message: "发起电话呼叫失败"))
                        }
                    }
                } else {
                    continuation.resume(returning: Result(success: false, message: "无法拨打电话"))
                }
            }
        }
    }
}

/// 设置提醒处理器
private class SetReminderHandler: FunctionHandler {
    private let eventStore: EKEventStore?
    
    init(eventStore: EKEventStore?) {
        self.eventStore = eventStore
    }
    
    func handle(arguments: [String: Any]) async throws -> String {
        guard let title = arguments["title"] as? String,
              let timeString = arguments["time"] as? String else {
            throw OpenAIException("缺少必要参数")
        }
        
        let content = arguments["content"] as? String ?? ""
        let result = await setReminder(title: title, content: content, time: timeString)
        return "{\"result\": \"\(result.message)\"}"
    }
    
    private func setReminder(title: String, content: String, time: String) async -> Result {
        guard let eventStore = eventStore else {
            return Result(success: false, message: "事件存储未初始化")
        }
        
        // 请求日历权限
        let status = await requestCalendarAccess()
        guard status == .authorized else {
            return Result(success: false, message: "日历权限被拒绝")
        }
        
        // 解析时间
        let formatter = DateFormatter()
        formatter.dateFormat = "yyyy-MM-dd HH:mm"
        guard let date = formatter.date(from: time) else {
            return Result(success: false, message: "时间格式错误")
        }
        
        // 创建提醒
        let reminder = EKReminder(eventStore: eventStore)
        reminder.title = title
        reminder.notes = content
        reminder.calendar = eventStore.defaultCalendarForNewReminders()
        
        let alarm = EKAlarm(absoluteDate: date)
        reminder.addAlarm(alarm)
        
        do {
            try eventStore.save(reminder, commit: true)
            return Result(success: true, message: "提醒设置成功")
        } catch {
            return Result(success: false, message: "设置提醒失败：\(error.localizedDescription)")
        }
    }
    
    private func requestCalendarAccess() async -> EKAuthorizationStatus {
        return await withCheckedContinuation { continuation in
            eventStore?.requestAccess(to: .reminder) { granted, error in
                let status = EKEventStore.authorizationStatus(for: .reminder)
                continuation.resume(returning: status)
            }
        }
    }
}

/// 获取当前时间处理器
private class GetCurrentTimeHandler: FunctionHandler {
    func handle(arguments: [String: Any]) async throws -> String {
        let format = arguments["format"] as? String
        let result = getCurrentTime(format: format)
        return "{\"result\": \"\(result.message)\", \"time\": \"\(result.message)\"}"
    }
    
    private func getCurrentTime(format: String?) -> Result {
        let formatter = DateFormatter()
        
        if let format = format, !format.isEmpty {
            formatter.dateFormat = format
        } else {
            formatter.dateStyle = .full
            formatter.timeStyle = .full
            formatter.locale = Locale(identifier: "zh_CN")
        }
        
        let currentTime = formatter.string(from: Date())
        return Result(success: true, message: currentTime)
    }
}

/// 获取当前位置处理器
private class GetCurrentLocationHandler: FunctionHandler {
    private weak var systemHandler: SystemFunctionHandler?
    
    init(systemHandler: SystemFunctionHandler) {
        self.systemHandler = systemHandler
    }
    
    func handle(arguments: [String: Any]) async throws -> String {
        guard let systemHandler = systemHandler else {
            throw OpenAIException("系统处理器未初始化")
        }
        
        let result = await systemHandler.getCurrentLocation()
        return "{\"result\": \"\(result.message)\", \"success\": \(result.success)}"
    }
}

/// 媒体播放处理器
private class MediaPlayHandler: FunctionHandler {
    func handle(arguments: [String: Any]) async throws -> String {
        let result = controlMedia(action: "play")
        return "{\"result\": \"\(result.message)\"}"
    }
    
    private func controlMedia(action: String) -> Result {
        let commandCenter = MPRemoteCommandCenter.shared()
        
        switch action {
        case "play":
            // 发送播放命令通知
            NotificationCenter.default.post(name: NSNotification.Name("MediaPlay"), object: nil)
            return Result(success: true, message: "已开始播放媒体")
        default:
            return Result(success: false, message: "未知的媒体操作")
        }
    }
}

/// 媒体暂停处理器
private class MediaPauseHandler: FunctionHandler {
    func handle(arguments: [String: Any]) async throws -> String {
        let result = controlMedia(action: "pause")
        return "{\"result\": \"\(result.message)\"}"
    }
    
    private func controlMedia(action: String) -> Result {
        switch action {
        case "pause":
            // 发送暂停命令通知
            NotificationCenter.default.post(name: NSNotification.Name("MediaPause"), object: nil)
            return Result(success: true, message: "已暂停媒体播放")
        default:
            return Result(success: false, message: "未知的媒体操作")
        }
    }
}

/// 媒体上一首处理器
private class MediaPreviousHandler: FunctionHandler {
    func handle(arguments: [String: Any]) async throws -> String {
        let result = controlMedia(action: "previous")
        return "{\"result\": \"\(result.message)\"}"
    }
    
    private func controlMedia(action: String) -> Result {
        switch action {
        case "previous":
            // 发送上一首命令通知
            NotificationCenter.default.post(name: NSNotification.Name("MediaPrevious"), object: nil)
            return Result(success: true, message: "已切换到上一首")
        default:
            return Result(success: false, message: "未知的媒体操作")
        }
    }
}

/// 媒体下一首处理器
private class MediaNextHandler: FunctionHandler {
    func handle(arguments: [String: Any]) async throws -> String {
        let result = controlMedia(action: "next")
        return "{\"result\": \"\(result.message)\"}"
    }
    
    private func controlMedia(action: String) -> Result {
        switch action {
        case "next":
            // 发送下一首命令通知
            NotificationCenter.default.post(name: NSNotification.Name("MediaNext"), object: nil)
            return Result(success: true, message: "已切换到下一首")
        default:
            return Result(success: false, message: "未知的媒体操作")
        }
    }
}

/// 打开录音机处理器
private class OpenRecorderHandler: FunctionHandler {
    func handle(arguments: [String: Any]) async throws -> String {
        let result = openRecorder()
        return "{\"result\": \"\(result.message)\"}"
    }
    
    private func openRecorder() -> Result {
        // 尝试打开语音备忘录应用
        if let url = URL(string: "voicememos://") {
            if UIApplication.shared.canOpenURL(url) {
                UIApplication.shared.open(url)
                return Result(success: true, message: "已打开语音备忘录")
            }
        }
        
        return Result(success: false, message: "无法打开录音机应用")
    }
}