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

public class EventDataAndBus : MonoBehaviour
{
	//------------------------------------------
	public string BusName;
	//------------------------------------------
	private FMOD.DSP_READ_CALLBACK mReadCallback;
	private FMOD.DSP mCaptureDSP;
	private float[] mDataBuffer;
	private GCHandle mObjHandle;// = null;
	private uint mBufferLength;
	private int mChannels = 0;
	private FMOD.ChannelGroup currentMaster;
	//------------------------------------------
	private bool success = false;
	private bool dspCreated = false;
	//------------------------------------------
	const float WIDTH = 10.0f;
	const float HEIGHT = 1.0f;


	private void Start()
	{
		StartCoroutine(GetBus());
	}

	IEnumerator GetBus()
	{
		yield return new WaitForSeconds(1.0f);
		FMOD.RESULT result = FMODUnity.RuntimeManager.StudioSystem.getBus("bus:/Dialogue/Voice", out FMOD.Studio.Bus bus);
		if (result != FMOD.RESULT.OK)
		{
			Debug.Log(result.ToString() + "Get bus");
			yield return null;
		}
		bus.lockChannelGroup();
		FMODUnity.RuntimeManager.StudioSystem.flushCommands();
		FMODUnity.RuntimeManager.StudioSystem.flushSampleLoading();
		result = bus.getChannelGroup(out currentMaster);
		if (result != FMOD.RESULT.OK)
		{
			Debug.Log(result.ToString() + "Get CG");
			yield return null;
		}

		if (currentMaster.hasHandle() == false)
			Debug.Log("No master in start");

		success = true;
	}
	void Update()
	{
		if (success && !dspCreated)
		{
			// Assign the callback to a member variable to avoid garbage collection
			mReadCallback = CaptureDSPReadCallback;

			// Allocate a data buffer large enough for 8 channels, pin the memory to avoid garbage collection
			uint bufferLength;
			int numBuffers;
			FMODUnity.RuntimeManager.CoreSystem.getDSPBufferSize(out bufferLength, out numBuffers);
			mDataBuffer = new float[bufferLength * 8];
			mBufferLength = bufferLength;

			// Get a handle to this object to pass into the callback
			mObjHandle = GCHandle.Alloc(this);
			if (mObjHandle != null)
			{
				// Define a basic DSP that receives a callback each mix to capture audio
				FMOD.DSP_DESCRIPTION desc = new FMOD.DSP_DESCRIPTION();
				
				desc.numinputbuffers = 1;
				desc.numoutputbuffers = 1;
				desc.read = mReadCallback;
				desc.userdata = GCHandle.ToIntPtr(mObjHandle);

				if (FMODUnity.RuntimeManager.CoreSystem.createDSP(ref desc, out mCaptureDSP) == FMOD.RESULT.OK)
				{
					if (!currentMaster.hasHandle())
					{
						Debug.Log("No master");
						return;
					}
					FMOD.RESULT result = currentMaster.addDSP(0, mCaptureDSP);
					Debug.Log(result.ToString());
					if (result != FMOD.RESULT.OK)
					{
						Debug.LogWarningFormat("FMOD: Unable to add mCaptureDSP to the master channel group");
					}
					else
						dspCreated = true;
				}
				else
				{
					Debug.LogWarningFormat("FMOD: Unable to create a DSP: mCaptureDSP");
				}
			}
			else
			{
				Debug.LogWarningFormat("FMOD: Unable to create a GCHandle: mObjHandle");
			}
		}

		if (dspCreated)
		{
			// Do what you want with the captured data
			if (mChannels != 0)
			{
				float yOffset = 5.7f;

				for (int j = 0; j < mChannels; j++)
				{
					var pos = Vector3.zero;
					pos.x = WIDTH * -0.5f;
					for (int i = 0; i < mBufferLength; ++i)
					{
						pos.x += (WIDTH / mBufferLength);
						pos.y = mDataBuffer[i + j * mBufferLength] * HEIGHT;
						// Make sure Gizmos is enabled in the Unity Editor to show debug line draw for the captured channel data
						Debug.DrawLine(new Vector3(pos.x, yOffset + pos.y, 0), new Vector3(pos.x, yOffset - pos.y, 0), Color.green);
					}
					yOffset -= 1.9f;
				}
			}
		}
	}

	[AOT.MonoPInvokeCallback(typeof(FMOD.DSP_READ_CALLBACK))]
	static FMOD.RESULT CaptureDSPReadCallback(ref FMOD.DSP_STATE dsp_state, IntPtr inbuffer, IntPtr outbuffer, uint length, int inchannels, ref int outchannels)
	{
		FMOD.DSP_STATE_FUNCTIONS functions = (FMOD.DSP_STATE_FUNCTIONS)Marshal.PtrToStructure(dsp_state.functions, typeof(FMOD.DSP_STATE_FUNCTIONS));

		IntPtr userData;
		functions.getuserdata(ref dsp_state, out userData);

		GCHandle objHandle = GCHandle.FromIntPtr(userData);
		EventDataAndBus obj = objHandle.Target as EventDataAndBus;

		// Save the channel count out for the update function
		obj.mChannels = inchannels;

		// Copy the incoming buffer to process later
		int lengthElements = (int)length * inchannels;
		Marshal.Copy(inbuffer, obj.mDataBuffer, 0, lengthElements);

		// Copy the inbuffer to the outbuffer so we can still hear it
		Marshal.Copy(obj.mDataBuffer, 0, outbuffer, lengthElements);

		return FMOD.RESULT.OK;
	}

	void OnDestroy()
	{
		if (mObjHandle != null)// && success)
		{
			if (mCaptureDSP.hasHandle())
			{
				currentMaster.removeDSP(mCaptureDSP);

				// Release the DSP and free the object handle
				mCaptureDSP.release();
			}
			mObjHandle.Free();
		}
	}
}