using System;
using System.Runtime.InteropServices;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class AudioFFT : MonoBehaviour {

    // fmod variables
    private FMOD.System fmodSystem;
    private FMOD.Channel fmodChannel;
    private FMOD.ChannelGroup fmodChannelGroup;
    private FMOD.DSP fftDSP;
    private FMOD.Sound exampleSong;
    private FMOD.RESULT fmodResult;

    // sound variable
    private string soundName;

    // spectrum variables
    IntPtr unmanagedData;
    uint unmanagedDataLen = 0;
    FMOD.DSP_PARAMETER_FFT waveFormBuffer = new FMOD.DSP_PARAMETER_FFT();
    //float spectrum[];

    // Use this for initialization
    void Start () {
        soundName = "bensound-happyrock";


        FMODInitialize();
        LoadSong(soundName);
        Play();
        GetSpectrum();
    }

    private void FMODInitialize()
    {
        fmodResult = FMOD.Factory.System_Create(out fmodSystem); // creates the fmod system object
        FMODerrorCheck(fmodResult);
        if (fmodResult != FMOD.RESULT.OK)
            Debug.Log("ErrorSystem");

        //fmodResult = fmodSystem.setDSPBufferSize(1024, 4); // sets the internal mixing buffer, controls mixer latency or granularity
        fmodResult = fmodSystem.init(32, FMOD.INITFLAGS.NORMAL, IntPtr.Zero); // initializes fmodSystem normally
        FMODerrorCheck(fmodResult);
        if (fmodResult != FMOD.RESULT.OK)
            Debug.Log("ErrorInit");

        fmodResult = fmodSystem.getMasterChannelGroup(out fmodChannelGroup);

        fmodResult = fmodSystem.createDSPByType(FMOD.DSP_TYPE.FFT, out fftDSP);
        FMODerrorCheck(fmodResult);
        if (fmodResult != FMOD.RESULT.OK)
            Debug.Log("ErrorInit");

        fmodResult = fmodChannelGroup.addDSP(0, fftDSP);
        FMODerrorCheck(fmodResult);
        if (fmodResult != FMOD.RESULT.OK)
            Debug.Log("ErrorAddDSP");

        FMODerrorCheck(fmodResult);
    }

    private void LoadSong(string name)
    {
        fmodResult = fmodSystem.createStream(Application.dataPath + "/Sounds/" + name + ".mp3",
            FMOD.MODE.LOOP_NORMAL, out exampleSong); // creates a stream for the sound
        FMODerrorCheck(fmodResult);
        if (fmodResult != FMOD.RESULT.OK)
            Debug.Log("ErrorLoad");
    }

    private void Play()
    {
        fmodResult = fmodSystem.playSound(exampleSong, fmodChannelGroup, false, out fmodChannel); // plays the sound
        FMODerrorCheck(fmodResult);
        if (fmodResult != FMOD.RESULT.OK)
            Debug.Log("ErrorPlay");


        fmodResult = fmodChannel.setChannelGroup(fmodChannelGroup);
        fmodResult = fmodChannel.setMode(FMOD.MODE.LOOP_NORMAL);
        fmodResult = fmodChannel.setVolume(0.1f);
        FMODerrorCheck(fmodResult);
        if (fmodResult != FMOD.RESULT.OK)
            Debug.Log("ErrorAddDSP");
    }

    private void GetSpectrum()
    {
        fmodResult = fftDSP.getParameterData((int)FMOD.DSP_FFT.SPECTRUMDATA, out unmanagedData, out unmanagedDataLen);
        FMODerrorCheck(fmodResult);
        if (fmodResult != FMOD.RESULT.OK)
            Debug.Log("ErrorGetParameter");

        waveFormBuffer = (FMOD.DSP_PARAMETER_FFT)Marshal.PtrToStructure(unmanagedData, typeof(FMOD.DSP_PARAMETER_FFT));

        Debug.Log(waveFormBuffer.numchannels);
        for (int channel = 0; channel < waveFormBuffer.numchannels; channel++)
        {
            for (int bin = 0; bin < waveFormBuffer.length; bin++)
            {
                float val = waveFormBuffer.spectrum[channel][bin];
                Debug.Log(val);
            }
        }
    }

    private void Update()
    {
        fmodSystem.update();
    }

    private void OnApplicationQuit()
    {
        fmodResult = fmodSystem.release();
    }

    private void FMODerrorCheck(FMOD.RESULT res)
    {
        if (fmodResult != FMOD.RESULT.OK)
            Debug.Log(FMOD.Error.String(res));
    }
}