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

namespace MoreMountains.Tools
{
    /// <summary>
    /// This class manages an object pool of audiosources
    /// </summary>
    [Serializable]
    public class MMSoundManagerAudioPool 
    {
        protected List<AudioSource> _pool;
        
        /// <summary>
        /// Fills the pool with ready-to-use audiosources
        /// </summary>
        /// <param name="poolSize"></param>
        /// <param name="parent"></param>
        public virtual void FillAudioSourcePool(int poolSize, Transform parent)
        {
            if (_pool == null)
            {
                _pool = new List<AudioSource>();
            }
            
            if ((poolSize <= 0) || (_pool.Count >= poolSize))
            {
                return;
            }

            foreach (AudioSource source in _pool)
            {
                UnityEngine.Object.Destroy(source.gameObject);
            }

            for (int i = 0; i < poolSize; i++)
            {
                GameObject temporaryAudioHost = new GameObject("MMAudioSourcePool_"+i);
                AudioSource tempSource = temporaryAudioHost.AddComponent<AudioSource>();
                temporaryAudioHost.transform.SetParent(parent);
                temporaryAudioHost.SetActive(false);
                _pool.Add(tempSource);
            }
        }

        /// <summary>
        /// Disables an audio source after it's done playing
        /// </summary>
        /// <param name="duration"></param>
        /// <param name="targetObject"></param>
        /// <returns></returns>
        public virtual IEnumerator AutoDisableAudioSource(float duration, GameObject targetObject)
        {
            yield return MMCoroutine.WaitFor(duration);
            targetObject.SetActive(false);
        }

        /// <summary>
        /// Pulls an available audio source from the pool
        /// </summary>
        /// <param name="poolCanExpand"></param>
        /// <param name="parent"></param>
        /// <returns></returns>
        public virtual AudioSource GetAvailableAudioSource(bool poolCanExpand, Transform parent)
        {
            foreach (AudioSource source in _pool)
            {
                if (!source.gameObject.activeInHierarchy)
                {
                    source.gameObject.SetActive(true);
                    return source;
                }
            }

            if (poolCanExpand)
            {
                GameObject temporaryAudioHost = new GameObject("MMAudioSourcePool_"+_pool.Count);
                AudioSource tempSource = temporaryAudioHost.AddComponent<AudioSource>();
                temporaryAudioHost.transform.SetParent(parent);
                temporaryAudioHost.SetActive(true);
                _pool.Add(tempSource);
                return tempSource;
            }

            return null;
        }

        /// <summary>
        /// Stops an audiosource and returns it to the pool
        /// </summary>
        /// <param name="sourceToStop"></param>
        /// <returns></returns>
        public virtual bool FreeSound(AudioSource sourceToStop)
        {
            foreach (AudioSource source in _pool)
            {
                if (source == sourceToStop)
                {
                    source.Stop();
                    source.gameObject.SetActive(false);
                    return true;
                }
            }
            return false;
        }
    }
}