using System;
using System.Collections;
using System.Collections.Generic;
using Invector.vCamera;
using Invector.vCharacterController;
using PixelCrushers;
using UnityEngine;
using UnityEngine.Audio;
using Random = UnityEngine.Random;

namespace Beyond
{
    [RequireComponent(typeof(AudioSource))]
    public class MusicManager : Saver
    {
        // Start is called before the first frame update
        public AudioMixer m_audioMixer;

        [Range(0.05f, 1f)]
        public float m_targetVolume;

        public float m_blendTime = 1f;
        public float m_restTime = 10f;
        private float m_time = -1f;

        public enum State
        { NONE, EXPLORE, COMBAT, CUSTOM, DIALOG };

        public State m_state = State.NONE;
        private State m_prevState = State.NONE;
        public AudioClip[] m_ExploreClips;
        public AudioClip[] m_CombatClips;
        public AudioClip[] m_DialogueClips;
        public AudioSource m_musicSource;

        [Tooltip("If music index < 0, then random index is used")]
        public int m_MusicIndex = -1;

        private static MusicManager s_instance;
        private AudioClip m_currentClip;
        private AudioClip m_previousClip;
        private bool m_blendSounds = false;
        public bool shouldPlayRandomClipsFrolList = false;

        public bool isLocked = false;

        [Serializable]
        public class SaveData
        {
            public State state;
            public int musicIndex;
        }

        public static MusicManager instance
        {
            get { return s_instance; }
        }

        private void Awake()
        {
            m_musicSource.volume = 0;
            if (s_instance == null)
            {
                s_instance = this;
                m_musicSource = GetComponent<AudioSource>();
                m_musicSource.loop = false;
                UnmuteMusic();
                // m_musicSource.volume = m_targetVolume;
            }
            else
            {
                Debug.LogError("There are two music managers!");
                DestroyImmediate(gameObject);
            }
        }

        private void Start()
        {
            SetState(m_state);
            GameStateManager.Instance.m_OnStateChanged.AddListener((GameStateManager.State s) =>
            {
                if (s == GameStateManager.State.COMBAT)
                {
                    SetState(State.COMBAT);
                }
                else if (s == GameStateManager.State.NORMAL && m_prevState != State.COMBAT)
                {
                    SetState(m_prevState);
                }
            });
        }

        private DayNightSettings dayNightSettings;

        public void SetState(State state)
        {
            if (isLocked)
            {
                return;
            }
            m_prevState = m_state;
            AudioClip[] clips = null; ;
            switch (state)
            {
                case State.NONE:
                    break;

                case State.EXPLORE:
                    clips = m_ExploreClips;
                    break;

                case State.COMBAT:
                    clips = m_CombatClips;
                    break;

                case State.DIALOG:
                    clips = m_DialogueClips;
                    break;

                case State.CUSTOM:
                    break;
            }
            m_state = state;

            if (clips != null && clips.Length > 0)
            {
                //get random combat index and return to music that played before on its end
                if (state == State.COMBAT)
                {
                    int combatIndex = Random.Range(0, clips.Length);
                    PlayClip(clips[combatIndex]);
                    return;
                }
                if (m_MusicIndex < 0)
                {
                    m_MusicIndex = Random.Range(0, clips.Length);
                }
                m_MusicIndex = m_MusicIndex < clips.Length ? m_MusicIndex : clips.Length - 1;
                PlayClip(clips[m_MusicIndex]);
            }
            else
            {
                Stop();
            }
        }

        public void PlayDialogue()
        {
            PlayDialogue(-1);
        }

        public void PlayDialogue(int idx)
        {
            m_MusicIndex = idx;
            SetState(State.DIALOG);
        }

        public void PlayExploration()
        {
            PlayExploration(-1);
        }

        public void PlayExploration(int idx)
        {
            m_MusicIndex = idx;
            SetState(State.EXPLORE);
        }

        public void PlayCombat()
        {
            PlayCombat(-1);
        }

        public void PlayCombat(int idx)
        {
            if (isLocked)
            {
                return;
            }
            m_MusicIndex = idx;
            SetState(State.COMBAT);
        }

        public void SetPreviousState()
        {
            SetState(m_prevState);
        }

        public void StopDialogue()
        {
            SetState(m_prevState);
        }

        public void Stop()
        {
            m_musicSource.Stop();
        }

        /*
                public void OnCombat()
                {
                    OnCombat(0);
                }
                public void OnCombat(int idx)
                {
                    if (m_combatCtr <= 0)
                    {
                        m_MusicIndex = idx;
                        SetState(State.COMBAT);
                    }
                    m_combatCtr++;
                }

                public void OnCombatEnd()
                {
                    m_combatCtr--;
                    if (m_combatCtr == 0)
                    {
                        SetState(m_prevState);
                    }
                }
                */

        private IEnumerator PlayCoroutine(AudioClip clip)
        {
            m_previousClip = m_currentClip;
            float volRate = m_targetVolume / m_blendTime;
            while (m_musicSource.isPlaying)
            {
                m_musicSource.volume -= volRate * Time.deltaTime;
                if (m_musicSource.volume <= 0f)
                {
                    break;
                }
                yield return null;
            }
            m_musicSource.clip = clip;
            m_currentClip = clip;
            m_musicSource.volume = 0f;
            m_musicSource.Play();
            m_time = 0f;
            while (m_musicSource.volume < m_targetVolume)
            {
                m_musicSource.volume += volRate * Time.deltaTime;
                yield return null;
            }
            m_musicSource.volume = m_targetVolume;
            //m_musicSource.PlayDelayed(0f);

            yield return null;
        }

        private void PlayClip(AudioClip clip)
        {
            //is previous clip playing
            StopAllCoroutines();
            StartCoroutine(PlayCoroutine(clip));
        }

        private float m_savedTargetVolume = 0.5f;

        /// <summary>
        /// for cutscenes with music in them
        /// </summary>
        public void MuteMusic()
        {
            //  m_savedTargetVolume = m_targetVolume;
            // m_targetVolume = 0f;
            StopAllCoroutines();
            StartCoroutine(DimMusic());
        }

        private IEnumerator DimMusic()
        {
            while (m_musicSource.isPlaying)
            {
                m_musicSource.volume -= Time.deltaTime;
                if (m_musicSource.volume <= 0f)
                {
                    enabled = false;
                    break;
                }
                yield return null;
            }
        }

        public void UnmuteMusic()
        {
            enabled = true;
            StopAllCoroutines();
            StartCoroutine(TurnOnMusic());
        }

        private IEnumerator TurnOnMusic()
        {
            m_musicSource.Play();
            while (m_musicSource.volume <= m_targetVolume)
            {
                m_musicSource.volume += Time.deltaTime;
                yield return null;
            }
        }

        /// <summary>
        /// used for night scenery, so entering zones doesnt change current soundtrack
        /// </summary>
        /// <param name="index"></param>
        public void PlayLockedMusic(int index)
        {
            isLocked = false;
            m_MusicIndex = index;
            SetState(State.EXPLORE);
            isLocked = true;
        }

        public void PlayUnlockedExploration(int index)
        {
            isLocked = false;
            m_MusicIndex = index;
            SetState(State.EXPLORE);
        }

        private void OnEnable()
        {
            // GameManager.instance.gameTime.m_DayNightEvent.AddListener(OnDayToNight);
        }

        private void OnDisable()
        {
            //        GameManager.instance.gameTime.m_DayNightEvent.RemoveListener(OnDayToNight);
        }

        public override string RecordData()
        {
            SaveData saveData = new SaveData();
            saveData.musicIndex = m_MusicIndex;
            saveData.state = m_state;
            return SaveSystem.Serialize(saveData);
        }

        public override void ApplyData(string s)
        {
            SaveData sd = SaveSystem.Deserialize<SaveData>(s);
            if (sd != null)
            {
                switch (sd.state)
                {
                    case State.COMBAT:
                        PlayCombat(sd.musicIndex);
                        break;
                    case State.CUSTOM:
                        break;
                    case State.DIALOG:
                        PlayDialogue(sd.musicIndex);
                        break;
                    case State.EXPLORE:
                        PlayExploration(sd.musicIndex);
                        break;
                }
            }
        }

        private IEnumerator BlendVolume(bool day)
        {
            /*
            m_time = 0f;
            if (day)
            {
                m_daySounds.SetActive(true);
            }
            else
            {
                m_nightSounds.SetActive(true);
            }
            while (m_time < m_blendTime)
            {
                float a = m_time / (m_blendTime);
                float volA = Mathf.Lerp(m_targetVolume, -80f, a);
                float volB = Mathf.Lerp(-80f, m_targetVolume, a);
                if (day)
                {
                    m_dayVolume = volB;
                    m_nightVolume = volA;
                }
                else
                {
                    m_dayVolume = volA;
                    m_nightVolume = volB;
                }

                m_audioMixer.SetFloat("DayVolume", m_dayVolume);
                m_audioMixer.SetFloat("NightVolume", m_nightVolume);
                m_audioMixer.SetFloat("DayMusicVolume", m_dayVolume);
                m_audioMixer.SetFloat("NightMusicVolume", m_nightVolume);
                m_time += Time.deltaTime;
                yield return null;
            }
            if (day)
            {
                m_nightSounds.SetActive(false);
                m_nightMusicSource.enabled = false;
            }
            else
            {
                m_daySounds.SetActive(false);
                m_dayMusicSource.enabled = false;
            }
            */
            yield return null;
        }

        private bool CheckIfShouldPlayNext()
        {
            if (m_musicSource.isPlaying)
                return false;
            if (m_time < m_restTime)
            {
                m_time += Time.deltaTime;
                return false;
            }

            return true;
        }

        // Update is called once per frame
        public void Update()
        {
            switch (m_state)
            {
                case State.EXPLORE:
                    if (CheckIfShouldPlayNext())
                    {
                        TryToChangeMusicIndex();
                        PlayExploration(m_MusicIndex);
                    }
                    break;

                case State.NONE:
                    break;

                case State.COMBAT:
                    if (CheckIfShouldPlayNext())
                    {
                        PlayCombat(m_MusicIndex);
                    }
                    break;

                case State.CUSTOM:
                    break;

                case State.DIALOG:
                    if (CheckIfShouldPlayNext())
                    {
                        PlayDialogue(m_MusicIndex);
                    }
                    break;
            }
        }

        private void TryToChangeMusicIndex()
        {
            if (shouldPlayRandomClipsFrolList)
            {
                m_MusicIndex = Random.Range(0, m_ExploreClips.Length);
            }
        }
    }
}