namespace QuikDawEditor.SampleProviders;

public class BufferedSampleProvider : ISampleProvider
{
    private CircularFloatBuffer circularFloatBuffer;
    private readonly WaveFormat waveFormat;
    public WaveFormat WaveFormat => waveFormat;

    public BufferedSampleProvider(WaveFormat waveFormat)
    {
        this.waveFormat = waveFormat;
        BufferLength = waveFormat.SampleRate * 5;
        ReadFully = true;

    }

    public bool ReadFully { get; set; }
    public int BufferLength { get; set; }

    public TimeSpan BufferDuration
    {
        get { return TimeSpan.FromSeconds((double)BufferLength / waveFormat.SampleRate); }
        set { BufferLength = (int)(value.TotalSeconds * waveFormat.SampleRate); }
    }

    public bool DiscardOnBufferOverflow { get; set; }
    public int BufferedSamples { get { return circularFloatBuffer == null ? 0 : circularFloatBuffer.Count; } }
    public TimeSpan BufferedDuration { get { return TimeSpan.FromSeconds((double)BufferedSamples / waveFormat.SampleRate); } }

    public void AddSamples(float[] buffer, int offset, int count)
    {
        // create buffer here to allow user to customise buffer length
        if (circularFloatBuffer == null)
            circularFloatBuffer = new CircularFloatBuffer(BufferLength);

        var written = circularFloatBuffer.Write(buffer, offset, count);

        if (written < count && !DiscardOnBufferOverflow)
            throw new InvalidOperationException("Buffer full");

    }

    public int Read(float[] buffer, int offset, int count)
    {
        int read = 0;
        if (circularFloatBuffer != null) // not yet created
            read = circularFloatBuffer.Read(buffer, offset, count);

        if (ReadFully && read < count)
        {
            // zero the end of the buffer
            Array.Clear(buffer, offset + read, count - read);
            read = count;
        }
        return read;
    }

    public void ClearBuffer() { if (circularFloatBuffer != null) { circularFloatBuffer.Reset(); } }

    public void ClearBufferTapered() { if (circularFloatBuffer != null) { circularFloatBuffer.ResetTaper(); } }

    
}