import Flutter
import UIKit
import AVFoundation

private let timerInterval: Double = 0.03
private let preTime: Double = 0.3
private let preLag: Double = 0.15

enum DubbingStatus {
    case stop, record, playRecord
}

public class SwiftDubbingLibPlugin: NSObject, FlutterPlugin {
    
    var registrar: FlutterPluginRegistrar!
    var channel: FlutterMethodChannel!
    
    var result: FlutterResult? = nil
    
    /// 当前界面配音状态
    var status: DubbingStatus = .stop
    var isRecording = false
    
    var audioRecorder: AVAudioRecorder?
    var audioPlayer: AVAudioPlayer?
    
    var initFlag: Bool = false
    
    public static func register(with registrar: FlutterPluginRegistrar) {
        let channel = FlutterMethodChannel(name: "dubbing_lib", binaryMessenger: registrar.messenger())
        let instance = SwiftDubbingLibPlugin()
        registrar.addMethodCallDelegate(instance, channel: channel)
        instance.channel = channel
        instance.registrar = registrar
    }
    
    public func handle(_ call: FlutterMethodCall, result: @escaping FlutterResult) {
        let args = call.arguments as? [String: Any];
        self.result = result;
        switch call.method {
        case "getPlatformVersion":
            result("iOS " + UIDevice.current.systemVersion)
            break
        case "startRecord":
            let duration = args!["duration"] as! Int;
            let fileName = args!["fileName"] as! String;
            let index = args!["index"] as! Int;
            let pathAudio = args!["pathAudio"] as! String;
            startRecord(pathAudio: pathAudio, index: index, duration: duration, fileName: fileName, result: result)
            break
        case "playRecordAudio":
            let filePath = args!["fileName"] as! String;
            playRecord(filePath: filePath, result: result)
            break
        case "pauseRecordAudio":
            audioPlayer?.pause()
            result(true)
            break
        case "startMixinAudio":
            let videoId = args!["videoId"] as! String;
            let videoPath = args!["videoPath"] as! String;
            let bgmPath = args!["bgmPath"] as! String;
            let audioPathList = args!["audioPathList"] as! [String];
            let startTimeList = args!["startTimeList"] as! [Double];
            let pathVideoMixinDir = args!["pathVideoMixin"] as! String;
            let outPath = pathVideoMixinDir + "\(videoId)_mix.mp4";
            startMixinAudio(videoPath: videoPath, bgmPath: bgmPath, audioPathList: audioPathList, startTimeList: startTimeList, outPath: outPath, result: result)
            break
        case "getIsMediaPlayPause":
            result(audioPlayer != nil && audioPlayer!.isPlaying)
            break
        case "cleanAudioData":
            break
        case "findIsExistCacheVideo":
            result("")
            break
        case "setExtraFullScreen":
            result("")
            break
        default:
            result(FlutterMethodNotImplemented)
        }
    }
    
    func initAudioSession(){
        do {
            if (!initFlag) {
                try AVAudioSession.sharedInstance().setCategory(AVAudioSession.Category.playAndRecord, options: .defaultToSpeaker)
                try AVAudioSession.sharedInstance().setActive(true)
                initFlag = true
            }
        } catch {
            initFlag = false
        }
    }
    
    func resultError(code: String, message: String) -> Void {
        self.result!(FlutterError(code: code, message: message, details: nil))
    }
    
    /// 合成
    func startMixinAudio(videoPath: String, bgmPath: String, audioPathList: [String], startTimeList: [Double], outPath: String, result: @escaping FlutterResult) {
        let videoUrl = URL(fileURLWithPath: videoPath)
        let musicUrl = URL(fileURLWithPath: bgmPath)
        let composer = DubbingComposer(timeline: startTimeList, videoUrl: videoUrl, musicUrl: musicUrl, recordsUrl: audioPathList)
        composer.preTime = preLag
        let outputUrl = URL(fileURLWithPath: outPath)
        DispatchQueue.global().async {
            composer.compose(outputUrl, onSuccess: {
                self.result!(outPath)
            }) { (message) in
                print("合成失败", message)
                self.resultError(code: "1005", message: "mix video and audio failed")
            }
        }
    }
}


// MARK: - 录音控制
extension SwiftDubbingLibPlugin {
    
    @objc func startRecord(pathAudio: String, index: Int, duration: Int, fileName: String, result: @escaping FlutterResult) {
        initAudioSession()
        endPlay()
        status = .record
        let filePath = pathAudio + fileName + ".aac";
        do {
            let settings: [String:Any] = [
                AVNumberOfChannelsKey : 1, //设置通道
                AVFormatIDKey : kAudioFormatMPEG4AAC, //设置录音格式
                //AVSampleRateKey : 16000, //设置录音采样率
                //AVLinearPCMBitDepthKey : 16, //每个采样点位数,分为8、16、24、32
                //AVLinearPCMIsFloatKey : true, //是否使用浮点数采样
            ]
            let url = URL(fileURLWithPath: filePath)
            audioRecorder = try AVAudioRecorder(url: url, settings: settings)
            audioRecorder?.prepareToRecord()
            audioRecorder?.record()
            isRecording = true
        } catch {
            stopRecord()
            resultError(code: "1002", message: "start record failed")
        }
        if(isRecording){
            var piecePosition = 0
            let queue:DispatchQueue = DispatchQueue.global(qos: DispatchQoS.QoSClass.default)
            let _timer:DispatchSource = DispatchSource.makeTimerSource(flags: [], queue: queue) as! DispatchSource
            _timer.schedule(deadline: DispatchTime.now(), repeating: .milliseconds(5))
            _timer.setEventHandler(handler: {() -> Void in
                self.isRecording = true
                piecePosition += 1
                self.channel.invokeMethod("recordProgress", arguments: ["progress": piecePosition * 5])
                if(piecePosition * 5 >= duration) {
                    _timer.cancel()
                    self.result!(filePath)
                    self.stopRecord()
                }
            })
            _timer.resume()
        } else {
            resultError(code: "1002", message: "start record failed")
        }
    }
    
    @objc func playRecord(filePath: String, result: @escaping FlutterResult) {
        status = .playRecord
        initAudioSession()
        do {
            let url = URL(fileURLWithPath: filePath)
            audioPlayer = try AVAudioPlayer(contentsOf: url)
            audioPlayer?.prepareToPlay()
            audioPlayer?.volume = 1
            audioPlayer?.delegate = self
            DispatchQueue.global().async {
                self.audioPlayer?.play()
            }
        } catch {
            stopPlayRecord()
        }
    }
    
    @objc func endPlay() {
        switch status {
        case .stop:
            break
        case .record:
            stopRecord()
        case .playRecord:
            stopPlayRecord()
        }
    }
    
    // 停止录音
    @objc func stopRecord() {
        status = .stop
        audioRecorder?.stop()
        audioRecorder = nil
        isRecording = false
    }
    
    // 停止播放录音
    func stopPlayRecord() {
        status = .stop
        if audioPlayer?.isPlaying == true {
            audioPlayer?.stop()
        }
        audioPlayer = nil
    }
}

extension SwiftDubbingLibPlugin: AVAudioPlayerDelegate {
    public func audioPlayerDidFinishPlaying(_ player: AVAudioPlayer, successfully flag: Bool) {
        stopPlayRecord()
        self.result!(flag)
    }
    
    public func audioPlayerDecodeErrorDidOccur(_ player: AVAudioPlayer, error: Error?) {
        stopPlayRecord()
        //        self.result!(false)
    }
}