import UIKit
import PushToTalk
import AVFoundation
import Kingfisher
import Accelerate

@available(iOS 16.0, *)
class PTTManager: NSObject, PTChannelRestorationDelegate {
   
    static let shared = PTTManager()
    
    private var channelManager: PTChannelManager?
    private var channelDescriptor: PTChannelDescriptor!
    private var channelUUID:UUID!
    var audioFilename:URL?

    
    /// 是否正在说话
    private var cs_isTalking = false
//    private var currentChannel: PTChannel?
    
    override init() {
        super.init()
        channelDescriptor = PTChannelDescriptor(name: "触说",
                                                image: UIImage(named: "logo"))
    }
    
    func setupChannelManager(channelUUID:UUID) {
        Task {
            self.channelUUID = channelUUID
            do {
                if channelManager == nil {
                    channelManager = try await PTChannelManager.channelManager(delegate: self,
                                                                               restorationDelegate: self)
                    try await channelManager?.setTransmissionMode(.fullDuplex,
                                                                  channelUUID: channelUUID)
                    
                    
                    self.requestJoinChannel()
                }else {
                    self.requestJoinChannel()
                }
            } catch {
                print("PPT初始化失败")
            }
        }
    }
    
    private func requestJoinChannel(){
        self.channelManager!.requestJoinChannel(channelUUID: self.channelUUID,
                                                    descriptor: self.channelDescriptor)
        self.channelManager!.setChannelDescriptor(channelDescriptor, channelUUID: self.channelUUID) { err in
            
        }
        if #available(iOS 17.0, *) {
            self.channelManager?.setAccessoryButtonEventsEnabled(true, channelUUID: channelUUID)
        } else {
            // Fallback on earlier versions
        }
        self.setServiceStatus(statu: .ready)
    }
    
    func leaveChannel(){
        if let channelManager = self.channelManager {
            stopTransmitting()
            channelManager.leaveChannel(channelUUID: channelUUID)
            self.setServiceStatus(statu: .unavailable)
        }
    }
    ///开始传输
    func requestBeginTransmitting(){
        if let channelManager = self.channelManager {
            channelManager.setActiveRemoteParticipant(nil, channelUUID: channelUUID) { err in
                
            }
            channelManager.requestBeginTransmitting(channelUUID: channelUUID)
            
        }else {
            print("请先PPT初始化")
        }
    }
    ///停止传输
    func stopTransmitting(){
        if let channelManager = self.channelManager {
            channelManager.stopTransmitting(channelUUID: channelUUID)
        }else {
            print("请先PPT初始化")
        }
    }
    
    ///恢复活跃的频道
    func channelDescriptor(restoredChannelUUID channelUUID: UUID) -> PTChannelDescriptor {
        return channelDescriptor
    }
    
    ///报告服务状态
    func setServiceStatus(statu:PTServiceStatus = .connecting) {
        Task {
            if let channelManager = self.channelManager {
                do {
                    try await channelManager.setServiceStatus(statu,
                                                          channelUUID: channelUUID)
                } catch {
                    print("PPT设置状态失败")
                }
            }
        }
      
    }
    func getAudioFileURL(convert:String = ".wav") -> URL {
        var documentsPath = FileManager.default.urls(for: .libraryDirectory, in: .userDomainMask)[0]
        documentsPath = documentsPath.appendingPathComponent("Caches")
        let fileName = "Voice_\(Int(Date().timeIntervalSince1970*1000))\(convert)"
        return documentsPath.appendingPathComponent(fileName)
    }
    
    var audioPlayer: AVAudioPlayer?

    func playRecording(url: URL) {
        do {
            let player = try AVAudioPlayer(contentsOf: url)
            player.prepareToPlay()
            player.play()
            print("🔊 播放录音: \(url.lastPathComponent)")
        } catch {
            print("❌ 播放失败:", error)
        }
    }
    
    private let engine = AVAudioEngine()
       private lazy var inputNode = engine.inputNode
       private let bus = 0
       private var audioFile: AVAudioFile?
    private var converter: AVAudioConverter?
    
   
    /// 开始录音并获取音频流
       func startEngineRecording() {
           let targetSampleRate: Double = 16000.0
           let inputFormat = inputNode.inputFormat(forBus: bus)
                  print("🎧 硬件输入格式: \(inputFormat)")
                  
                  // 目标格式：S16、单声道
                  guard let targetFormat = AVAudioFormat(commonFormat: .pcmFormatInt16,
                                                         sampleRate: targetSampleRate,
                                                         channels: 1,
                                                         interleaved: true) else {
                      print("❌ 创建目标格式失败")
                      return
                  }
                  
                  // 初始化转换器
                  converter = AVAudioConverter(from: inputFormat, to: targetFormat)
                  
                  // 每 10ms 数据
                  let frameCountPer10ms = AVAudioFrameCount(targetSampleRate * 0.01)
                  // 创建文件用于保存录音
                  do {
                      let url = getAudioFileURL()
                      audioFilename = url
                      audioFile = try AVAudioFile(forWriting: url, settings: inputFormat.settings)
                      print("✅ 录音文件路径：\(url.path)")
                  } catch {
                      print("❌ 创建音频文件失败: \(error.localizedDescription)")
                      return
                  }
           
           inputNode.removeTap(onBus: bus) // 避免重复安装
           // 安装 Tap 捕获音频流
                  inputNode.installTap(onBus: bus, bufferSize: 1024, format: inputFormat) { [weak self] buffer, time in
                      guard let self = self, let file = self.audioFile else { return }
                      
                      // 实时写入到文件
                      do {
                          try file.write(from: buffer)
                      } catch {
                          print("❌ 写入文件失败: \(error.localizedDescription)")
                      }
                      
                      guard let converter = self.converter else { return }
                                  
                                  // 输出缓冲区（Int16）
                                  guard let pcmBuffer = AVAudioPCMBuffer(pcmFormat: targetFormat,
                                                                         frameCapacity: frameCountPer10ms) else { return }
                                  
                                  var error: NSError?
                                  let inputBlock: AVAudioConverterInputBlock = { inNumPackets, outStatus in
                                      outStatus.pointee = .haveData
                                      return buffer
                                  }
                                  
                                  converter.convert(to: pcmBuffer, error: &error, withInputFrom: inputBlock)
                                  
                                  if let error = error {
                                      print("⚠️ 转换错误: \(error.localizedDescription)")
                                      return
                                  }
                                  
                                  // 获取PCM16数据
                                  let audioBuffer = pcmBuffer.audioBufferList.pointee.mBuffers
                                  let data = Data(bytes: audioBuffer.mData!, count: Int(audioBuffer.mDataByteSize))
                                  
                  }
                  do {
                      try engine.start()
                      print("🎤 开始录音并捕获音频流...")
                  } catch {
                      print("❌ 启动 AVAudioEngine 失败: \(error.localizedDescription)")
                  }
           
           print("🎧 输入格式:", targetFormat)
           print("🎧 文件格式:", audioFile?.fileFormat ?? "未知")
           print("🎧 写入设置:", targetFormat.settings)
       }
       
       /// 停止录音
       func stopEngineRecording() {
           cleanupEngineRecording()
       }
       
       func cleanupEngineRecording(){
           inputNode.removeTap(onBus: bus)
           engine.stop()
           stopTransmitting()
           if let audioFilename = self.audioFilename {
               playRecording(url: audioFilename)
           }
           print("录音已停止")
       }
}

@available(iOS 16.0, *)
extension PTTManager: PTChannelManagerDelegate {
    func channelManager(_ channelManager: PTChannelManager, didJoinChannel channelUUID: UUID, reason: PTChannelJoinReason) {
        print("加入通道")
    }
    
    func channelManager(_ channelManager: PTChannelManager, didLeaveChannel channelUUID: UUID, reason: PTChannelLeaveReason) {
        print("离开通道")
    }
    
    func channelManager(_ channelManager: PTChannelManager, channelUUID: UUID, didBeginTransmittingFrom source: PTChannelTransmitRequestSource) {
        
    }
    
    func channelManager(_ channelManager: PTChannelManager, channelUUID: UUID, didEndTransmittingFrom source: PTChannelTransmitRequestSource) {
        print("结束传输成功")
    }
    
    func channelManager(_ channelManager: PTChannelManager, receivedEphemeralPushToken pushToken: Data) {
        let deviceTokenStr = pushToken.map { String(format: "%02.2hhx", $0) }.joined()
        print("获取token\(deviceTokenStr)")
    }
    
    func channelManager(_ channelManager: PTChannelManager, didActivate audioSession: AVAudioSession) {
        print("已激活")
        
        DispatchQueue.main.asyncAfter(deadline: .now() + 0.3) {
            self.startEngineRecording()
            }
    }
    
    func channelManager(_ channelManager: PTChannelManager, didDeactivate audioSession: AVAudioSession) {
        print("已停用")
        stopEngineRecording()
    }
    
    ///每次传入推送都会调用此方法。您必须为每个传入的推送实例化并返回nonnil PTPushResult。系统将代表您自动执行PTBushResult指定的操作。
    func incomingPushResult(channelManager: PTChannelManager, channelUUID: UUID, pushPayload: [String : Any]) -> PTPushResult {
        
        guard let activeSpeaker = pushPayload["触说"] as? String else {
                // Report that there's no active speaker, so leave the channel.
                return .leaveChannel
            }


            let activeSpeakerImage = UIImage(named: "logo") // Get the cached image for the active speaker.
            let participant = PTParticipant(name: activeSpeaker,
                                            image: activeSpeakerImage)
            // Report the active participant information to the system.
            return .activeRemoteParticipant(participant)
    }
}