using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class AudioManager : MonoBehaviour
{
    private const int MaxChannels = 128;    // Should match MAX_CHANNELS in sound.h
    
    private FMOD.System fmodSystem;
    public FMOD.System FmodSystem => fmodSystem;

    private static AudioManager instance;
    public static AudioManager Instance
    {
        get
        {
            if (instance == null)
            {
                instance = FindObjectOfType<AudioManager>();
                if (instance == null)
                {
                    var gameObject = new GameObject("FMOD Audio Manager");
                    instance = gameObject.AddComponent<AudioManager>();
                }
            }

            return instance;
        }
    }
    
    void Awake()
    {
        FMOD.RESULT result = FMOD.Factory.System_Create(out fmodSystem);
        CheckFmodResult(result, "FMOD.Factory.System_Create");

        result = fmodSystem.getVersion(out uint version);
        CheckFmodResult(result, "FMOD.System.getVersion");
        
        Debug.LogFormat("[FMOD] Initialized FMOD System version {0:X1}.{1:X2}.{2:X2}",
            (version >> 16) & 0xFF, (version >> 8) & 0xFF, version & 0xFF);

        result = fmodSystem.getNumDrivers(out int numDrivers);
        CheckFmodResult(result, "FMOD.System.getNumDrivers");

        result = fmodSystem.setOutput(numDrivers > 0 ? FMOD.OUTPUTTYPE.AUTODETECT : FMOD.OUTPUTTYPE.NOSOUND);
        CheckFmodResult(result, "FMOD.System.setOutput");

        result = fmodSystem.getOutput(out FMOD.OUTPUTTYPE output);
        CheckFmodResult(result, "FMOD.System.getOutput");
        
        Debug.Log($"[FMOD] Using output type: {output}");

        result = fmodSystem.init(MaxChannels, FMOD.INITFLAGS.NORMAL, IntPtr.Zero);
        CheckFmodResult(result, "FMOD.System.init");
    }

    private void CheckFmodResult(FMOD.RESULT result, string cause)
    {
        if (result != FMOD.RESULT.OK)
        {
            if (fmodSystem.hasHandle())
            {
                fmodSystem.close();
                fmodSystem.release();
                fmodSystem.clearHandle();
            }
            throw new Exception($"[FMOD] Initialization failed : {cause} : {result.ToString()} : {FMOD.Error.String(result)}");
        }
    }
    
    private void OnDestroy()
    {
        if (fmodSystem.hasHandle())
        {
            fmodSystem.close();
            fmodSystem.release();
            fmodSystem.clearHandle();
        }
    }
}