using System.Collections.Generic;
using UnityEngine;
using GTAAudioSharp;
using System.IO;
using SanAndreasUnity.Audio;

namespace SanAndreasUnity.Behaviours.Audio
{
	
	public class AudioManager : MonoBehaviour
	{

		public static AudioManager Instance { get; private set; }

		private static GTAAudioFiles s_gtaAudioFiles;
		public static GTAAudioFiles AudioFiles { get { return s_gtaAudioFiles; } }

	//	private Dictionary<string, AudioClip> sfxAudioClips = new Dictionary<string, AudioClip>();

	//	private Dictionary<string, AudioClip> streamsAudioClips = new Dictionary<string, AudioClip>();

	//	private Dictionary<string, AudioStream> streamsAudioStreams = new Dictionary<string, AudioStream>();

		public bool playStartupSound = true;
		public float startupSoundTimeOffset = 0f;
		static AudioSource s_startupAudioSource;

		public const int kSfxSampleSize = 2;

	//	static AudioClip s_sfxGENRLClip;
	//	public static AudioClip SfxGENRLClip { get { return s_sfxGENRLClip; } }

		// describes single sound inside sfx bank
		public struct SfxBankAudioData
		{
			public int startTimeMs;
		//	public int lengthMs;
		//	public float lengthSeconds { get { return this.lengthMs / 1000f; } }
			public int bitrateKbs;	// kb/s
			public int offsetInBytes;
			public int bitsPerSecond { get { return this.bitrateKbs * 1000; } }
			public float bytesPerSecond { get { return this.bitsPerSecond / 8f; } }
		//	public int sizeInBytes { get { return Mathf.RoundToInt( this.lengthSeconds * this.bytesPerSecond ); } }
			public int sizeInBytes;
		}

		static SfxBankAudioData[] s_sfxGENRL137Timings;
		public static SfxBankAudioData[] SfxGENRL137Timings { get { return s_sfxGENRL137Timings; } }



		void Awake ()
		{
			Instance = this;
		}

		void OnDisable ()
		{
			if (s_gtaAudioFiles != null)
			{
				s_gtaAudioFiles.Dispose ();
				s_gtaAudioFiles = null;
			}
		}

		void Start () {
			
		}

		void OnLoaderFinished ()
		{
			if (s_startupAudioSource != null)
			{
				Destroy (s_startupAudioSource.gameObject);
			}
		}

		void Update () {
			
		}


		public static void InitFromLoader ()
		{

			s_gtaAudioFiles = GTAAudio.OpenRead (Path.Combine (Utilities.Config.GamePath, "audio"));

			s_sfxGENRL137Timings = LoadSfxBankTimings (Path.Combine (Utilities.Config.DataPath, "SFX_GENRL_137.txt"));

			if (Instance.playStartupSound)
			{
				s_startupAudioSource = PlayStream ("Beats", 1);
				if (s_startupAudioSource != null)
					s_startupAudioSource.time = Instance.startupSoundTimeOffset;
			}

		//	s_sfxGENRLClip = CreateAudioClipFromSfx ("GENRL", 136, 0);

		}

		public static SfxBankAudioData[] LoadSfxBankTimings (string filePath)
		{
		//	int sampleSize = 2;
			System.IFormatProvider formatProvider = System.Globalization.CultureInfo.InvariantCulture;
			var lines = File.ReadAllLines (filePath);
			SfxBankAudioData[] datas = new SfxBankAudioData[(lines.Length - 1)];	// skip last line
		//	int currentTime = 0;
			float currentOffset = 0;
			for (int i = 0, lineIndex = 0; i < datas.Length; i++)
			{
				string[] splits = lines [lineIndex++].Split (' ');

			//	datas [i].startTimeMs = currentTime;
			//	datas [i].offsetInBytes = Mathf.RoundToInt (currentOffset);

			//	int clipLengthMs = int.Parse (lines [lineIndex++], formatProvider);
			//	datas [i].lengthMs = clipLengthMs;

			//	int bitrate = 288;//int.Parse (lines [lineIndex++], formatProvider);
			//	lineIndex ++;
			//	datas [i].bitrateKbs = bitrate;

			//	currentTime += clipLengthMs;
			//	currentOffset += (clipLengthMs / 1000f) * (bitrate * 1000f / 8f);

				datas [i].offsetInBytes = int.Parse (splits [0]);
				datas [i].sizeInBytes = int.Parse (splits [1]);
				datas [i].bitrateKbs = Mathf.RoundToInt( FreqToKbs( int.Parse (splits [2]) ) );

			}
		//	Debug.LogFormat ("sfx timings loaded - current offset {0}", currentOffset);
			return datas;
		}


		public static AudioClip CreateAudioClipFromStream (string streamFileName, int bankIndex)
		{
			AudioStream audio_stream = null;
			System.DateTime startTime = System.DateTime.Now;

			int streams_bank_index = bankIndex;
			string streams_file_name = streamFileName;
			string key = streams_file_name + "." + streams_bank_index;


			if ((s_gtaAudioFiles != null) && (streams_bank_index >= 0))
			{
				try
				{
					Stream stream = s_gtaAudioFiles.OpenStreamsAudioStreamByName(streams_file_name, (uint)streams_bank_index);
					if (stream != null)
					{
						audio_stream = new AudioStream(stream, key, true);
					}
				}
				catch (System.Exception e)
				{
					Debug.LogError(e);
				}
			}


			if (audio_stream != null)
			{
				System.TimeSpan time_span = System.DateTime.Now - startTime;
				Debug.Log("\"" + key + "\" took " + time_span.TotalSeconds + " seconds.");

				return audio_stream.AudioClip;
			}

			return null;
		}

		public static AudioSource PlayStream (string streamFileName, int bankIndex)
		{
			var clip = CreateAudioClipFromStream (streamFileName, bankIndex);
			if (clip != null)
			{
				AudioSource audioSource = new GameObject (streamFileName + "." + bankIndex).AddComponent<AudioSource> ();
				audioSource.time = 0.0f;
				audioSource.clip = clip;
				audioSource.Play();

				// destroy game object when sound is finished playing
				Destroy( audioSource.gameObject, clip.length );

				return audioSource;
			}

			return null;
		}

		public static AudioClip CreateAudioClipFromSfx (string sfxFileName, int bankIndex, int audioIndex, SfxBankAudioData? sfxBankAudioData)
		{

			if (null == s_gtaAudioFiles || bankIndex < 0 || audioIndex < 0)
				return null;
			
			AudioClip ret = null;
			string clipName = sfxFileName + "." + bankIndex + "." + audioIndex;

			try
			{
				using (GTAAudioStream audio_stream = s_gtaAudioFiles.OpenSFXAudioStreamByName(sfxFileName, (uint)bankIndex, (uint)audioIndex))
				{
					if (audio_stream != null)
					{
						// this audio stream holds all sounds from this bank

						int freq = sfxBankAudioData.HasValue ? Mathf.RoundToInt( KbsToFreq( sfxBankAudioData.Value.bitrateKbs ) ) : audio_stream.SampleRate ;
						int offsetInBytes = sfxBankAudioData.HasValue ? sfxBankAudioData.Value.offsetInBytes : 0 ;
						int sizeInBytes = sfxBankAudioData.HasValue ? sfxBankAudioData.Value.sizeInBytes : (int) audio_stream.Length ;

						ret = CreateAudioClipFromSfx (clipName, audio_stream, offsetInBytes, sizeInBytes, freq);

					}
				}
			}
			catch (System.Exception e)
			{
				Debug.LogError(e);
			}

			return ret;
		}

		public static AudioClip CreateAudioClipFromSfx (string clipName, GTAAudioStream audio_stream, int offsetInBytes, int sizeInBytes, int frequency)
		{
			AudioClip ret = null;

			audio_stream.Position = offsetInBytes;

			byte[] int_pcm = new byte[sizeInBytes];

			if (audio_stream.Read(int_pcm, 0, int_pcm.Length) == int_pcm.Length)
			{
				float[] float_pcm = new float[int_pcm.Length / sizeof(short)];
				for (int i = 0; i < float_pcm.Length; i++)
				{
					float_pcm[i] = Mathf.Clamp(((short)(int_pcm[i * sizeof(short)] | (int_pcm[(i * sizeof(short)) + 1] << 8)) / 32767.5f), -1.0f, 1.0f);
				}
				ret = AudioClip.Create(clipName, float_pcm.Length, 1, frequency, false);
				ret.SetData(float_pcm, 0);

				// Debug.LogFormat("loaded sfx: name {0}, offset {1}, size {2}, length {3}, bitrate Kb/s {4}, stream size {5}, freq {6}", 
				// 	clipName, offsetInBytes, sizeInBytes, ret.length,
				// 	FreqToKbs (frequency), audio_stream.Length, frequency);
			}

			return ret;
		}

		static float FreqToKbs(int freq)
		{
			return freq * kSfxSampleSize * 8f / 1000f;
		}

		static float KbsToFreq(float kbs)
		{
			return kbs / 8f * 1000f / kSfxSampleSize;
		}

	}

}