using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using NSpeex;

namespace SafeMobileLib
{

    public class NspeexAndro
    {
        private Mode mode;
        private int quality;
        private readonly NSpeex.Decoder decoder;
        private readonly NSpeex.Encoder encoder;
        private readonly PreProcessor preProcessor;
        private JitterBufferWaveProvider waveProvider;

        public NspeexAndro(Mode m)
        {
            mode = m;
            //quality = Q;
            //decoder
            decoder = new NSpeex.Decoder(m);
            waveProvider = new JitterBufferWaveProvider(m);
           
            //encoder
            encoder = new NSpeex.Encoder(m);
            encoder.Quality = 5;
            encoder.VBR = true;
            preProcessor = new PreProcessor(encoder) { AGC = true, AGCIncrement = 3, Denoise = true, VAD = true };

        }

        public void AddAudio4Decode(byte[] data)
        {
            BinaryReader reader = new BinaryReader(new MemoryStream(data));

            //while (reader.PeekChar() != -1)
            while (reader.BaseStream.Length - reader.BaseStream.Position > 4)
            {
                int frameLength = reader.ReadInt32();
                //Console.WriteLine("frame len" + frameLength);
                byte[] frame = reader.ReadBytes(frameLength);
                waveProvider.Write(frame, 0, frameLength);              
            }
        }

        public long Length
        {
            get { return waveProvider.Length; }
        }

        public int GetDecodedAudio(byte[] data, int offset, int size)
        {
            if (waveProvider.HasData(size))
                return waveProvider.Read(data, offset, size);
            else
                return 0;
        }

        public byte[] Encode(byte[] data, int offset, int size)
        {
            int samplesPerFrame = encoder.FrameSize;
            byte[] buffer = data;
            short[] frame = new short[samplesPerFrame];
            byte[] encodedFrame = new byte[size];
            int encodedBytesSample = 0;
            byte[] upstreamEncodedSample = new byte[size];

            int frameIndex = 0;
            for (int index = 0; index < size; index += 2, frameIndex = ++frameIndex % samplesPerFrame)
            {
                frame[frameIndex] = BitConverter.ToInt16(buffer, index);
                if (frameIndex != samplesPerFrame - 1) continue;
                if (preProcessor.Process(frame))
                {
                    int encodedBytes = encoder.Encode(frame, encodedFrame);
                    if (encodedBytes != 0)
                    {
                        Array.Copy(BitConverter.GetBytes(encodedBytes), 0, upstreamEncodedSample, encodedBytesSample,
                                   sizeof(int));
                        encodedBytesSample += 4;
                        Array.Copy(encodedFrame, 0, upstreamEncodedSample, encodedBytesSample, encodedBytes);
                        encodedBytesSample += encodedBytes;
                    }
                }
            }

            if (frameIndex != 0)
            {
                while (frameIndex < samplesPerFrame)
                {
                    // fill the last frame with 0s
                    frame[frameIndex++] = 0;
                }

                int encodedBytes = encoder.Encode(frame, encodedFrame);
                if (encodedBytes != 0)
                {
                    Array.Copy(BitConverter.GetBytes(encodedBytes), 0, upstreamEncodedSample, encodedBytesSample,
                               sizeof(int));
                    encodedBytesSample += 4;
                    Array.Copy(encodedFrame, 0, upstreamEncodedSample, encodedBytesSample, encodedBytes);
                    encodedBytesSample += encodedBytes;
                }
            }

            if (encodedBytesSample != 0)
            {
                var upstreamFrame = new byte[encodedBytesSample];
                Array.Copy(upstreamEncodedSample, upstreamFrame, encodedBytesSample);

                //SM.Debug("Publishing: " + encodedBytesSample + " bytes");
                /*
                if (OnNewDataRecv != null)
                {
                    OnNewDataRecv(upstreamFrame, encodedBytesSample);
                }
                 */
                return upstreamFrame;
            }
            else
            {
                return null;
                //Console.WriteLine("DTX");
            }
        }

        public TimeSpan TotalTime
        {
            get { return waveProvider.TotalTime; }
        }
        public delegate void newData4Send(byte[] data, int dataLen);
        public event newData4Send OnNewDataRecv;
    }

    public class AndroEncodedPack
    {
        public int frameSize;
        public byte[] frame;
    }

}