using System;
using System.Collections;
using System.Collections.Generic;
using System.Net.WebSockets;
using System.Security.Cryptography;
using System.Text;
using System.Threading;
using UnityEngine;
using Microphone = FrostweepGames.MicrophonePro.Microphone;
public class XunFeiSTT : STT
{
    [SerializeField] private string APPID = "f2433640";
    [SerializeField] private string APIKey = "d46a0dc56145c074ae751940ca74caf4";
    [SerializeField] private string APISecret = "OTU4YTU4ZmY2OGYyYzQxYTA2ZTc5OWM5";

    private ClientWebSocket webSocket;
    private AudioClip RecordedClip;
    private string microphoneDevice;
    private Action<string> callBack;
    private void Awake()
    {
        m_SpeechRecognizeURL = "wss://iat-api.xfyun.cn/v2/iat";
    }
    public override void StartSpeechToText(Action<string> _callback = null)
    {
        base.StartSpeechToText(_callback);
        // Get the default microphone
        microphoneDevice = Microphone.devices.Length > 0 ? Microphone.devices[0] : null;

        if (string.IsNullOrEmpty(microphoneDevice))
        {
            Debug.LogError("没找到麦克风!");
            return;
        }
        Begin();
    }
    public override void StopSpeechToText(Action<string> _callback = null)
    {
        base.StopSpeechToText(_callback);
        if (string.IsNullOrEmpty(microphoneDevice))
        {
            Debug.LogError("没找到麦克风!");
            return;
        }
        callBack = _callback;
        StartCoroutine(End());
    }
    public void Begin()
    {
        //if (webSocket != null && webSocket.State == WebSocketState.Open)
        //{
        //    Debug.LogWarning("开始语音识别失败！，等待上次识别连接结束");
        //    return;
        //}
        Connect();
        RecordedClip = Microphone.Start(null, false, 60, 16000);
    }

    public IEnumerator End()
    {
        Microphone.End(null);
        yield return new WaitUntil(() => webSocket.State != WebSocketState.Open);
        //Debug.Log("识别结束，停止录音");
    }

    async void Connect()
    {
        using (webSocket = new ClientWebSocket())
        {
            CancellationToken ct = new CancellationToken();
            Uri url = new Uri(GetUrl(m_SpeechRecognizeURL));
            await webSocket.ConnectAsync(url, ct);
            //Debug.Log("连接成功");
            StartCoroutine(Send(webSocket));
            StringBuilder stringBuilder = new StringBuilder();
            while (webSocket.State == WebSocketState.Open)
            {
                try
                {
                    var result = new byte[4096];
                    await webSocket.ReceiveAsync(new ArraySegment<byte>(result), ct);//接受数据
                    List<byte> list = new List<byte>(result); while (list[list.Count - 1] == 0x00) list.RemoveAt(list.Count - 1);//去除空字节
                    string str = Encoding.UTF8.GetString(list.ToArray());
                    //Debug.Log("接收消息：" + str);
                    if (string.IsNullOrEmpty(str))
                    {
                        return;
                    }
                    STTData data = JsonUtility.FromJson<STTData>(str);
                    stringBuilder.Append(Get(data));
                    int status = data.data.status;
                    if (status == 2)
                    {
                        webSocket.Abort();
                    }
                }
                catch (Exception)
                {
                    webSocket.Abort();
                    return;
                }
            }
            //Debug.LogWarning("断开连接");
            string s = stringBuilder.ToString();
            if (!string.IsNullOrEmpty(s))
            {
                callBack?.Invoke(s);
                Debug.LogWarning("识别到声音：" + s);
            }
        }
    }

    [Serializable]
    public class STTData
    {
        [Serializable]
        public class Data
        {
            [Serializable]
            public class Result
            {
                [Serializable]
                public class Ws
                {
                    [Serializable]
                    public class Cw
                    {
                        public string w;
                    }
                    public Cw[] cw;
                }
                public Ws[] ws;
            }
            public int status;
            public Result result;
        }
        public Data data;
    }

    string Get(STTData data)
    {
        StringBuilder stringBuilder = new StringBuilder();
        var ws = data.data.result.ws;
        foreach (var item in ws)
        {
            var cw = item.cw;
            foreach (var w in cw)
            {
                stringBuilder.Append(w.w);
            }
        }
        return stringBuilder.ToString();
    }

    void SendData(byte[] audio, int status, ClientWebSocket socket)
    {
        if (socket.State != WebSocketState.Open)
        {
            return;
        }
        string audioStr = audio == null ? "" : Convert.ToBase64String(audio);
        string message = "{\"common\":{\"app_id\":\"" + APPID + "\"},\"business\":{\"language\":\"zh_cn\",\"domain\":\"iat\",\"accent\":\"mandarin\",\"vad_eos\":2000}," +
            "\"data\":{\"status\":" + status + ",\"encoding\":\"raw\",\"format\":\"audio/L16;rate=16000\",\"audio\":\"" + audioStr + "\"}}";
        //Debug.Log("发送消息:" + message);
        socket.SendAsync(new ArraySegment<byte>(Encoding.UTF8.GetBytes(message)), WebSocketMessageType.Binary, true, new CancellationToken()); //发送数据
    }

    IEnumerator Send(ClientWebSocket socket)
    {
        yield return new WaitWhile(() => Microphone.GetPosition(null) <= 0);
        float t = 0;
        int position = Microphone.GetPosition(null);
        const float waitTime = 0.04f;//每隔40ms发送音频
        int status = 0;
        int lastPosition = 0;
        const int Maxlength = 640;//最大发送长度
        while (position < RecordedClip.samples && socket.State == WebSocketState.Open)
        {
            t += waitTime;
            yield return new WaitForSecondsRealtime(waitTime);
            if (Microphone.IsRecording(null)) position = Microphone.GetPosition(null);
            //Debug.Log("录音时长：" + t + "position=" + position + ",lastPosition=" + lastPosition);
            if (position <= lastPosition)
            {
                //Debug.LogWarning("字节流发送完毕！强制结束！");
                break;
            }
            int length = position - lastPosition > Maxlength ? Maxlength : position - lastPosition;
            byte[] date = GetClip(lastPosition, length, RecordedClip);
            SendData(date, status, socket);
            lastPosition = lastPosition + length;
            status = 1;
        }
        SendData(null, 2, socket);
        //WebSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, "关闭WebSocket连接",new CancellationToken());
        Microphone.End(null);
    }
    public static byte[] GetClip(int star, int length, AudioClip recordedClip)
    {
        float[] soundata = new float[length];
        recordedClip.GetData(soundata, star);
        int rescaleFactor = 32767;
        byte[] outData = new byte[soundata.Length * 2];
        for (int i = 0; i < soundata.Length; i++)
        {
            short temshort = (short)(soundata[i] * rescaleFactor);
            byte[] temdata = BitConverter.GetBytes(temshort);
            outData[i * 2] = temdata[0];
            outData[i * 2 + 1] = temdata[1];
        }
        return outData;
    }
    string GetUrl(string uriStr)
    {
        Uri uri = new Uri(uriStr);
        string date = DateTime.Now.ToString("r");
        string signature_origin = string.Format("host: " + uri.Host + "\ndate: " + date + "\nGET " + uri.AbsolutePath + " HTTP/1.1");
        HMACSHA256 mac = new HMACSHA256(Encoding.UTF8.GetBytes(APISecret));
        string signature = Convert.ToBase64String(mac.ComputeHash(Encoding.UTF8.GetBytes(signature_origin)));
        string authorization_origin = string.Format("api_key=\"{0}\",algorithm=\"hmac-sha256\",headers=\"host date request-line\",signature=\"{1}\"", APIKey, signature);
        string authorization = Convert.ToBase64String(Encoding.UTF8.GetBytes(authorization_origin));
        string url = string.Format("{0}?authorization={1}&date={2}&host={3}", uri, authorization, date, uri.Host);
        return url;
    }
}