using UnityEngine;
using UnityEngine.Audio;
using System.Collections;
using System.Collections.Generic;
#if UNITY_EDITOR
using UnityEditor;
using System;
using System.Reflection;
#endif

namespace OVR
{

public enum PreloadSounds {
	Default,		// default unity behavior
	Preload,		// audio clips are forced to preload
	ManualPreload,	// audio clips are forced to not preload, preloading must be done manually
}

public enum Fade
{
    In,
    Out
}

[System.Serializable]
public class SoundGroup {
	public SoundGroup( string name ) {
		this.name = name;
	}
	public SoundGroup() {
		mixerGroup = null;
		maxPlayingSounds = 0;
		preloadAudio = PreloadSounds.Default;
		volumeOverride = 1.0f;
	}
	public void IncrementPlayCount() {
		playingSoundCount = Mathf.Clamp( ++playingSoundCount, 0, maxPlayingSounds );
	}
	public void DecrementPlayCount() {
		playingSoundCount = Mathf.Clamp( --playingSoundCount, 0, maxPlayingSounds );
	}
	public bool CanPlaySound() {
		return ( maxPlayingSounds == 0 ) || ( playingSoundCount < maxPlayingSounds );
	}

	public string			name = string.Empty;
	public SoundFX[]		soundList = new SoundFX[0];
	public AudioMixerGroup  mixerGroup = null;						// default = AudioManager.defaultMixerGroup
	[Range(0,64)]
	public int              maxPlayingSounds = 0;                   // default = 0, unlimited
	// TODO: this preload behavior is not yet implemented
	public PreloadSounds	preloadAudio = PreloadSounds.Default;	// default = true, audio clip data will be preloaded
	public float            volumeOverride = 1.0f;					// default = 1.0

	[HideInInspector]
	public int              playingSoundCount = 0;
}

/*
-----------------------

 AudioManager

-----------------------
*/
public partial class AudioManager : MonoBehaviour {

	[Tooltip("Make the audio manager persistent across all scene loads")]
	public bool							makePersistent = true;							// true = don't destroy on load
	[Tooltip("Enable the OSP audio plugin features")]
	public bool							enableSpatializedAudio = true;                  // true = enable spatialized audio
	[Tooltip("Always play spatialized sounds with no reflections (Default)")]
	public bool                         enableSpatializedFastOverride = false;          // true = disable spatialized reflections override
	[Tooltip("The audio mixer asset used for snapshot blends, etc.")]
	public AudioMixer                   audioMixer = null;
	[Tooltip( "The audio mixer group used for the pooled emitters" )]
	public AudioMixerGroup				defaultMixerGroup = null;
	[Tooltip( "The audio mixer group used for the reserved pool emitter" )]
	public AudioMixerGroup				reservedMixerGroup = null;
	[Tooltip( "The audio mixer group used for voice chat" )]
	public AudioMixerGroup				voiceChatMixerGroup = null;
	[Tooltip("Log all PlaySound calls to the Unity console")]
	public bool							verboseLogging = false;							// true = log all PlaySounds
	[Tooltip("Maximum sound emitters")]
	public int 							maxSoundEmitters = 32;							// total number of sound emitters created
	[Tooltip("Default volume for all sounds modulated by individual sound FX volumes")]
	public float						volumeSoundFX = 1.0f;							// user pref: volume of all sound FX
	[Tooltip("Sound FX fade time")]
	public float						soundFxFadeSecs = 1.0f;							// sound FX fade time
	
	public float						audioMinFallOffDistance = 1.0f;					// minimum falloff distance
	public float						audioMaxFallOffDistance = 25.0f;				// maximum falloff distance

	public SoundGroup[]					soundGroupings = new SoundGroup[0];

	private Dictionary<string,SoundFX>	soundFXCache = null;

	static private AudioManager			theAudioManager = null;
	static private FastList<string> 	names = new FastList<string>();
	static private string[]				defaultSound = new string[1] { "Default Sound" };
	static private SoundFX				nullSound = new SoundFX();
	static private bool					hideWarnings = false;
	static public bool 					enableSpatialization { get { return ( theAudioManager !=null ) ? theAudioManager.enableSpatializedAudio : false; } }

	static public AudioManager			Instance { get { return theAudioManager; } }
	static public float					NearFallOff { get { return theAudioManager.audioMinFallOffDistance; } }
	static public float					FarFallOff { get { return theAudioManager.audioMaxFallOffDistance; } }
	static public AudioMixerGroup		EmitterGroup { get { return theAudioManager.defaultMixerGroup; } }
	static public AudioMixerGroup		ReservedGroup { get { return theAudioManager.reservedMixerGroup; } }
	static public AudioMixerGroup		VoipGroup { get { return theAudioManager.voiceChatMixerGroup; } }

	/*
	-----------------------
	Awake()
	-----------------------
	*/
	void Awake() {
		Init();
	}

	/*
	-----------------------
	OnDestroy()
	-----------------------
	*/
	void OnDestroy() {
		// we only want the initialized audio manager instance cleaning up the sound emitters
		if ( theAudioManager == this ) {
			if ( soundEmitterParent != null ) {
				Destroy( soundEmitterParent );
			}
		}
		///TODO - if you change scenes you'll want to call OnPreSceneLoad to detach the sound emitters
		///from anything they might be parented to or they will get destroyed with that object
		///there should only be one instance of the AudioManager across the life of the game/app
		///GameManager.OnPreSceneLoad -= OnPreSceneLoad;
	}

	/*
	-----------------------
	Init()
	-----------------------
	*/
	void Init() {
		if ( theAudioManager != null ) {
			if ( Application.isPlaying && ( theAudioManager != this ) ) {
				enabled = false;
			}
			return;
		}
		theAudioManager = this;

		///TODO - if you change scenes you'll want to call OnPreSceneLoad to detach the sound emitters
		///from anything they might be parented to or they will get destroyed with that object
		///there should only be one instance of the AudioManager across the life of the game/app
		///GameManager.OnPreSceneLoad += OnPreSceneLoad;

		// make sure the first one is a null sound
		nullSound.name = "Default Sound";

		// build the sound FX cache
		RebuildSoundFXCache();

		// create the sound emitters
		if ( Application.isPlaying ) {
			InitializeSoundSystem();
			if ( makePersistent && ( transform.parent == null ) ) {
				// don't destroy the audio manager on scene loads
				DontDestroyOnLoad( gameObject );
			}
		}

#if UNITY_EDITOR
		Debug.Log( "[AudioManager] Initialized..." );
#endif
	}

	/*
	-----------------------
	Update()
	-----------------------
	*/
	void Update() {
		// update the free and playing lists
		UpdateFreeEmitters();
	}

	/*
	-----------------------
	RebuildSoundFXCache()
	-----------------------
	*/
	void RebuildSoundFXCache() {
		// build the SoundFX dictionary for quick name lookups
		int count = 0;
		for ( int group = 0; group < soundGroupings.Length; group++ ) {
			count += soundGroupings[group].soundList.Length;
		}
		soundFXCache = new Dictionary<string,SoundFX>( count + 1 );	
		// add the null sound
		soundFXCache.Add( nullSound.name, nullSound );
		// add the rest
		for ( int group = 0; group < soundGroupings.Length; group++ ) {
			for ( int i = 0; i < soundGroupings[group].soundList.Length; i++ ) {
				if ( soundFXCache.ContainsKey( soundGroupings[group].soundList[i].name ) ) {
					Debug.LogError( "ERROR: Duplicate Sound FX name in the audio manager: '" + soundGroupings[group].name + "' > '" + soundGroupings[group].soundList[i].name + "'" );
				} else {
					soundGroupings[group].soundList[i].Group = soundGroupings[group];
					soundFXCache.Add( soundGroupings[group].soundList[i].name, soundGroupings[group].soundList[i] );
				}
			}
			soundGroupings[group].playingSoundCount = 0;
		}
	}

	/*
	-----------------------
	FindSoundFX()
	-----------------------
	*/
	static public SoundFX FindSoundFX( string name, bool rebuildCache = false ) {
#if UNITY_EDITOR
		if ( theAudioManager == null ) {
			Debug.LogError( "ERROR: audio manager not yet initialized or created!" + " Time: " + Time.time  );
			return null;
		}
#endif
		if ( string.IsNullOrEmpty( name ) ) {
			return nullSound;
		}
		if ( rebuildCache ) {
			theAudioManager.RebuildSoundFXCache();
		}
		if ( !theAudioManager.soundFXCache.ContainsKey( name ) ) {
#if DEBUG_BUILD || UNITY_EDITOR
			Debug.LogError( "WARNING: Missing Sound FX in cache: " + name );
#endif
			return nullSound;
		}
		return theAudioManager.soundFXCache[name];
	}

	/*
	-----------------------
	FindAudioManager()
	-----------------------
	*/
	static private bool FindAudioManager() {
		GameObject audioManagerObject = GameObject.Find( "AudioManager" );
		if ( ( audioManagerObject == null ) || ( audioManagerObject.GetComponent<AudioManager>() == null ) ) {
			if ( !hideWarnings ) {
				Debug.LogError( "[ERROR] AudioManager object missing from hierarchy!" );
				hideWarnings = true;
			}
			return false;
		} else {
			audioManagerObject.GetComponent<AudioManager>().Init();
		}
		return true;
	}

	/*
	-----------------------
	GetGameObject()
	-----------------------
	*/
	static public GameObject GetGameObject() {
		if ( theAudioManager == null ) {
			if ( !FindAudioManager() ) {
				return null;
			}
		}
		return theAudioManager.gameObject;
	}

	/*
	-----------------------
	NameMinusGroup()
	strip off the sound group from the inspector dropdown
	-----------------------
	*/
	static public string NameMinusGroup( string name ) {
		if ( name.IndexOf( "/" ) > -1 ) {
			return name.Substring( name.IndexOf( "/" ) + 1 );
		}
		return name;
	}
	
	/*
	-----------------------
	GetSoundFXNames()
	used by the inspector
	-----------------------
	*/
	static public string[] GetSoundFXNames( string currentValue, out int currentIdx ) {
		currentIdx = 0;
		names.Clear();
		if ( theAudioManager == null ) {
			if ( !FindAudioManager() ) {
				return defaultSound;
			}
		}
		names.Add( nullSound.name );
		for ( int group = 0; group < theAudioManager.soundGroupings.Length; group++ ) {
			for ( int i = 0; i < theAudioManager.soundGroupings[group].soundList.Length; i++ ) {
				if ( string.Compare( currentValue, theAudioManager.soundGroupings[group].soundList[i].name, true ) == 0 ) {
					currentIdx = names.Count;
				}
				names.Add( theAudioManager.soundGroupings[group].name + "/" + theAudioManager.soundGroupings[group].soundList[i].name );
			}
		}
		//names.Sort( delegate( string s1, string s2 ) { return s1.CompareTo( s2 ); } );
		return names.ToArray();

	}
#if UNITY_EDITOR
	/*
	-----------------------
	OnPrefabReimported()
	-----------------------
	*/
	static public void OnPrefabReimported() {
		if ( theAudioManager != null ) {
			Debug.Log( "[AudioManager] Reimporting the sound FX cache." );
			theAudioManager.RebuildSoundFXCache();
		}
	}

	/*
	-----------------------
	PlaySound()
	used in the editor
	-----------------------
	*/
	static public void PlaySound( string soundFxName ) {
		if ( theAudioManager == null ) {
			if ( !FindAudioManager() ) {
				return;
			}
		}
		SoundFX soundFX = FindSoundFX( soundFxName, true );
		if ( soundFX == null ) {
			return;
		}
		AudioClip clip = soundFX.GetClip();
		if ( clip != null ) {
			Assembly unityEditorAssembly = typeof(AudioImporter).Assembly;
			Type audioUtilClass = unityEditorAssembly.GetType("UnityEditor.AudioUtil");
			MethodInfo method = audioUtilClass.GetMethod(
				"PlayClip",
				BindingFlags.Static | BindingFlags.Public,
				null,
				new System.Type[] { typeof(AudioClip) },
				null );
			method.Invoke( null, new object[] { clip } );
		}
	}

	/*
	-----------------------
	IsSoundPlaying()
	used in the editor
	-----------------------
	*/
	static public bool IsSoundPlaying( string soundFxName ) {
		if ( theAudioManager == null ) {
			if ( !FindAudioManager() ) {
				return false;
			}
		}
		SoundFX soundFX = FindSoundFX( soundFxName, true );
		if ( soundFX == null ) {
			return false;
		}
		AudioClip clip = soundFX.GetClip();
		if ( clip != null ) {
			Assembly unityEditorAssembly = typeof(AudioImporter).Assembly;
			Type audioUtilClass = unityEditorAssembly.GetType("UnityEditor.AudioUtil");
			MethodInfo method = audioUtilClass.GetMethod(
				"IsClipPlaying",
				BindingFlags.Static | BindingFlags.Public,
				null,
				new System.Type[] { typeof(AudioClip) },
				null );
			return Convert.ToBoolean( method.Invoke( null, new object[] { clip } ) );
		}

		return false;
	}

	/*
	-----------------------
	StopSound()
	used in the editor
	-----------------------
	*/
	static public void StopSound(string soundFxName)
	{
		if (theAudioManager == null)
		{
			if (!FindAudioManager())
			{
				return;
			}
		}
		SoundFX soundFX = FindSoundFX(soundFxName, true);
		if (soundFX == null)
		{
			return;
		}
		AudioClip clip = soundFX.GetClip();
		if (clip != null)
		{
			Assembly unityEditorAssembly = typeof(AudioImporter).Assembly;
			Type audioUtilClass = unityEditorAssembly.GetType("UnityEditor.AudioUtil");
			MethodInfo method = audioUtilClass.GetMethod(
				"StopClip",
				BindingFlags.Static | BindingFlags.Public,
				null,
				new System.Type[] { typeof(AudioClip) },
				null);
			method.Invoke(null, new object[] { clip });
		}
	}
#endif
}

} // namespace OVR