import Foundation
import CoreBluetooth
import AVFoundation
import UIKit

/// 蓝牙事件处理协议
@objc protocol BluetoothEventHandler: AnyObject {
    func sendEvent(_ event: [String: Any])
}

@objc class ClassicBluetoothHelper: NSObject {
    // MARK: - 属性
    
    // 音频会话管理器
    private let audioSessionManager = AudioSessionManager.shared
    

    // 事件处理器
    private weak var eventHandler: BluetoothEventHandler?
    
    // MARK: - 初始化与设置
    
    override init() {
        super.init()
    }
    
    // 设置事件处理器
    @objc func setEventHandler(_ handler: BluetoothEventHandler) {
        eventHandler = handler
    }
    
    
    // MARK: - 设备监控
    
    // 获取蓝牙状态字符串
    private func getBluetoothStateString(state: CBManagerState) -> String {
        switch state {
        case .poweredOn:
            return "on"
        case .poweredOff:
            return "off"
        default:
            return "unknown"
        }
    }
    
    // 发送蓝牙状态事件
    private func sendBluetoothStateEvent(state: String) {
        let event: [String: Any] = [
            "type": "bluetoothStateChanged",
            "state": state,
            "timestamp": Int(Date().timeIntervalSince1970 * 1000)
        ]
        eventHandler?.sendEvent(event)
    }
    
    // 启动蓝牙设备监控
    @objc func startBluetoothDeviceMonitoring() {
        NotificationCenter.default.removeObserver(self)
        audioSessionManager.addRouteChangeListener(self, selector: #selector(handleRouteChange(_:)))
        BluetoothMediaButtonHelper.shared.startButtonListening()
    }
    
    // 处理音频路由变化
    @objc private func handleRouteChange(_ notification: Notification) {
        guard let userInfo = notification.userInfo,
              let reasonValue = userInfo[AVAudioSessionRouteChangeReasonKey] as? UInt,
              let reason = AVAudioSession.RouteChangeReason(rawValue: reasonValue) else {
            return
        }
        
        // 获取当前设备
        let currentDevices = getConnectedAudioDevices()
        
        // 检查原因
        switch reason {
        case .newDeviceAvailable:
            // 新设备已连接
            for device in currentDevices {
                // 发送设备连接事件
                NSLog("发送设备连接事件 - 设备: \(device["name"] ?? "未知设备") [\(device["address"] ?? "未知地址")]")
                sendDeviceConnectedEvent(device: device)
            }
            
        case .oldDeviceUnavailable:
            // 获取断开之前的路由
            if let previousRoute = userInfo[AVAudioSessionRouteChangePreviousRouteKey] as? AVAudioSessionRouteDescription {
                // 过滤蓝牙相关设备
                for output in previousRoute.outputs where isBluetoothOutput(output.portType) {
                    let device: [String: String] = [
                        "name": output.portName,
                        "address": cleanDeviceAddress(output.uid)
                    ]
                    // 发送设备断开事件
                    sendDeviceDisconnectedEvent(device: device)
                }
            }
            
        default:
            break
        }
    }
    
    // 检查是否为蓝牙输出
    private func isBluetoothOutput(_ portType: AVAudioSession.Port) -> Bool {
        return portType == .bluetoothA2DP || portType == .bluetoothHFP || portType == .bluetoothLE
    }
    
    // MARK: - 设备事件
    
    // 发送设备已连接事件
    private func sendDeviceConnectedEvent(device: [String: String]) {
        let event: [String: Any] = [
            "type": "deviceConnected",
            "device": device,
            "timestamp": Int(Date().timeIntervalSince1970 * 1000)
        ]
        eventHandler?.sendEvent(event)
    }
    
    // 发送设备已断开事件
    private func sendDeviceDisconnectedEvent(device: [String: String]) {
        let event: [String: Any] = [
            "type": "deviceDisconnected",
            "device": device,
            "timestamp": Int(Date().timeIntervalSince1970 * 1000)
        ]
        eventHandler?.sendEvent(event)
    }
    
    // MARK: - 公共API
    
    // 获取当前连接的耳机设备
    @objc func getConnectedHeadsetDevices(_ completion: @escaping ([[String: String]]?, String?) -> Void) {

        do {
            // 获取设备
            let devices = getConnectedAudioDevices()
            completion(devices, nil)
        } catch {
            completion(nil, "获取设备失败: \(error.localizedDescription)")
        }
    }
    
    // 获取当前连接的音频设备
    private func getConnectedAudioDevices() -> [[String: String]] {
        var result: [[String: String]] = []
        
        // 获取当前音频路由
        let outputs = audioSessionManager.getCurrentRoute().outputs
        
        // 过滤蓝牙相关设备
        for output in outputs where isBluetoothOutput(output.portType) {
            let device: [String: String] = [
                "name": output.portName,
                "address": cleanDeviceAddress(output.uid) // 处理设备地址，移除后缀
            ]
            result.append(device)
        }
        
        return result
    }

    
    // 检查蓝牙是否启用
    @objc func isBluetoothEnabled() -> Bool {
        return audioSessionManager.isBluetoothEnabled()
    }
    
    // 清理设备地址，移除后缀
    private func cleanDeviceAddress(_ address: String) -> String {
        // 检查是否包含常见分隔符
        if let range = address.range(of: "-") ?? address.range(of: ":") ?? address.range(of: "_") {
            // 只保留分隔符之前的部分
            return String(address[..<range.lowerBound])
        }
        
        // iOS设备UID有时会包含额外信息，尝试只保留标准MAC地址格式部分
        // MAC地址通常是12个十六进制字符，可能带有分隔符
        let hexPattern = "[0-9A-Fa-f]{2}(:[0-9A-Fa-f]{2}){5}|[0-9A-Fa-f]{12}"
        if let regex = try? NSRegularExpression(pattern: hexPattern, options: []),
           let match = regex.firstMatch(in: address, options: [], range: NSRange(location: 0, length: address.utf16.count)) {
            let matchRange = match.range
            if let range = Range(matchRange, in: address) {
                return String(address[range])
            }
        }
        
        return address
    }
}