using OptimeGBA;
using System;
using UnityEngine;


public class AudioProvider : MonoBehaviour
{
    [SerializeField]
    private AudioSource m_as;
    private RingBuffer<float> _buffer;
    private TimeSpan lastElapsed;
    public double audioFPS { get; private set; }
    float lastData = 0;

    public void Awake()
    {
        AudioClip clip = AudioClip.Create("dummy", GbaAudio.SampleRate * 2, 2, GbaAudio.SampleRate, true);
        AudioSettings.GetDSPBufferSize(out int bufferLength, out _);
        _buffer = new RingBuffer<float>(bufferLength * 2 * 2);
        m_as.clip = clip;
        m_as.playOnAwake = true;
        //m_as.loop = true;
        m_as.spatialBlend = 1;
    }
    public void Initialize()
    {
        if (!m_as.isPlaying)
        {
            m_as.Play();
        }
    }
    private void OnAudioFilterRead(float[] data, int channels)
    {
        int step = channels;
        step = 1;
        for (int i = 0; i < data.Length; i += step)
        {
            if (_buffer.TryRead(out float rawData))
                data[i] = rawData;
            else
                break;
        }

        //int step = channels;
        //step = 1;
        //for (int i = 0; i < data.Length; i += step)
        //{
        //    float rawFloat = lastData;
        //    if (_buffer.TryRead(out float rawData))
        //    {
        //        rawFloat = rawData;
        //    }

        //    data[i] = rawFloat;
        //    for (int fill = 1; fill < step; fill++)
        //        data[i + fill] = rawFloat;
        //    lastData = rawFloat;
        //}
    }


    public void AudioReady(float[] data)
    {
        if (!Emulator.instance.EnableAudio) return;

        var current = Emulator.sw.Elapsed;
        var delta = current - lastElapsed;
        lastElapsed = current;
        audioFPS = 1d / delta.TotalSeconds;

        for (int i = 0; i < data.Length; i++)
        {
            _buffer.Write(data[i]);
        }
    }
}