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

namespace Streamingle.Contents.BossRaid
{
    /// <summary>
    /// 보스 레이드 효과음/BGM 관리.
    /// Resources/Audio 폴더에서 파일명 규칙으로 자동 로드합니다.
    ///
    /// 파일명 규칙:
    ///   sfx_hit_normal, sfx_hit_critical, sfx_hit_miss,
    ///   sfx_boss_appear, sfx_boss_rage, sfx_boss_death,
    ///   sfx_victory, sfx_damage_popup, sfx_phase_transition,
    ///   bgm_battle_normal, bgm_battle_rage, bgm_victory
    /// </summary>
    public class BossRaidAudio : MonoBehaviour
    {
        #region Constants

        private const string AudioPath = "Audio/";

        // SFX 키
        public const string SFX_HIT_NORMAL = "sfx_hit_normal";
        public const string SFX_HIT_CRITICAL = "sfx_hit_critical";
        public const string SFX_HIT_MISS = "sfx_hit_miss";
        public const string SFX_BOSS_APPEAR = "sfx_boss_appear";
        public const string SFX_BOSS_RAGE = "sfx_boss_rage";
        public const string SFX_BOSS_DEATH = "sfx_boss_death";
        public const string SFX_VICTORY = "sfx_victory";
        public const string SFX_DAMAGE_POPUP = "sfx_damage_popup";
        public const string SFX_PHASE_TRANSITION = "sfx_phase_transition";

        // 보스 공격
        public const string SFX_BOSS_BREATH = "sfx_boss_breath";
        public const string SFX_BOSS_SLAM = "sfx_boss_slam";
        public const string SFX_BOSS_CHARGE = "sfx_boss_charge";

        // 유저 피격
        public const string SFX_PLAYER_HIT = "sfx_player_hit";
        public const string SFX_PLAYER_DEATH = "sfx_player_death";
        public const string SFX_GAME_OVER = "sfx_game_over";

        // BGM 키
        public const string BGM_BATTLE_NORMAL = "bgm_battle_normal";
        public const string BGM_BATTLE_RAGE = "bgm_battle_rage";
        public const string BGM_VICTORY = "bgm_victory";

        #endregion

        #region Fields

        [Header("AudioSource")]
        [SerializeField] private AudioSource sfxSource;
        [SerializeField] private AudioSource bgmSource;

        [Header("BGM 설정")]
        [SerializeField]
        [Range(0f, 1f)]
        private float bgmVolume = 0.5f;

        [SerializeField] private float bgmFadeDuration = 1f;

        [Header("SFX 설정")]
        [SerializeField]
        [Range(0f, 1f)]
        private float sfxVolume = 1f;

        private Dictionary<string, AudioClip> _clipCache = new Dictionary<string, AudioClip>();
        private Coroutine _bgmFadeCoroutine;

        #endregion

        #region Unity Messages

        private void Awake()
        {
            EnsureAudioSources();
            PreloadAll();
        }

        #endregion

        #region Public Methods

        /// <summary>
        /// 키 이름으로 SFX를 재생합니다.
        /// </summary>
        public void PlaySFX(string key)
        {
            var clip = GetClip(key);
            if (clip == null || sfxSource == null) return;
            sfxSource.PlayOneShot(clip, sfxVolume);
        }

        /// <summary>
        /// 키 이름으로 SFX를 랜덤 피치로 재생합니다.
        /// </summary>
        public void PlaySFXRandomPitch(string key, float minPitch = 0.9f, float maxPitch = 1.1f)
        {
            var clip = GetClip(key);
            if (clip == null || sfxSource == null) return;

            float originalPitch = sfxSource.pitch;
            sfxSource.pitch = Random.Range(minPitch, maxPitch);
            sfxSource.PlayOneShot(clip, sfxVolume);
            sfxSource.pitch = originalPitch;
        }

        /// <summary>
        /// 키 이름으로 BGM을 페이드 인 재생합니다.
        /// </summary>
        public void PlayBGM(string key)
        {
            var clip = GetClip(key);
            if (clip == null || bgmSource == null) return;

            if (_bgmFadeCoroutine != null)
                StopCoroutine(_bgmFadeCoroutine);

            _bgmFadeCoroutine = StartCoroutine(CrossfadeBGM(clip));
        }

        /// <summary>
        /// BGM을 페이드 아웃으로 정지합니다.
        /// </summary>
        public void StopBGM()
        {
            if (bgmSource == null) return;

            if (_bgmFadeCoroutine != null)
                StopCoroutine(_bgmFadeCoroutine);

            _bgmFadeCoroutine = StartCoroutine(FadeOutBGM());
        }

        /// <summary>
        /// 모든 오디오를 즉시 정지합니다.
        /// </summary>
        public void StopAll()
        {
            if (_bgmFadeCoroutine != null)
            {
                StopCoroutine(_bgmFadeCoroutine);
                _bgmFadeCoroutine = null;
            }
            sfxSource?.Stop();
            if (bgmSource != null)
            {
                bgmSource.Stop();
                bgmSource.clip = null;
                bgmSource.volume = 0f;
            }
        }

        /// <summary>
        /// BGM 볼륨을 설정합니다. (0~1)
        /// </summary>
        public float BGMVolume
        {
            get => bgmVolume;
            set
            {
                bgmVolume = Mathf.Clamp01(value);
                if (bgmSource != null && bgmSource.isPlaying)
                    bgmSource.volume = bgmVolume;
            }
        }

        /// <summary>
        /// SFX 볼륨을 설정합니다. (0~1)
        /// </summary>
        public float SFXVolume
        {
            get => sfxVolume;
            set => sfxVolume = Mathf.Clamp01(value);
        }

        /// <summary>
        /// 캐시에서 로드된 클립 수를 반환합니다.
        /// </summary>
        public int LoadedClipCount => _clipCache.Count;

        #endregion

        #region Private Methods

        private void PreloadAll()
        {
            string[] keys = new[]
            {
                SFX_HIT_NORMAL, SFX_HIT_CRITICAL, SFX_HIT_MISS,
                SFX_BOSS_APPEAR, SFX_BOSS_RAGE, SFX_BOSS_DEATH,
                SFX_VICTORY, SFX_DAMAGE_POPUP, SFX_PHASE_TRANSITION,
                SFX_BOSS_BREATH, SFX_BOSS_SLAM, SFX_BOSS_CHARGE,
                SFX_PLAYER_HIT, SFX_PLAYER_DEATH, SFX_GAME_OVER,
                BGM_BATTLE_NORMAL, BGM_BATTLE_RAGE, BGM_VICTORY,
            };

            int loaded = 0;
            foreach (var key in keys)
            {
                var clip = Resources.Load<AudioClip>(AudioPath + key);
                if (clip != null)
                {
                    _clipCache[key] = clip;
                    loaded++;
                }
            }

            Debug.Log($"[BossRaidAudio] {loaded}/{keys.Length}개 오디오 로드 완료");
        }

        private AudioClip GetClip(string key)
        {
            if (string.IsNullOrEmpty(key)) return null;

            if (_clipCache.TryGetValue(key, out var cached))
                return cached;

            // 캐시에 없으면 다시 로드 시도
            var clip = Resources.Load<AudioClip>(AudioPath + key);
            if (clip != null)
                _clipCache[key] = clip;

            return clip;
        }

        private void EnsureAudioSources()
        {
            if (sfxSource == null)
            {
                var sfxObj = new GameObject("BossRaid_SFX");
                sfxObj.transform.SetParent(transform);
                sfxSource = sfxObj.AddComponent<AudioSource>();
                sfxSource.playOnAwake = false;
                sfxSource.spatialBlend = 0f;
            }

            if (bgmSource == null)
            {
                var bgmObj = new GameObject("BossRaid_BGM");
                bgmObj.transform.SetParent(transform);
                bgmSource = bgmObj.AddComponent<AudioSource>();
                bgmSource.playOnAwake = false;
                bgmSource.loop = true;
                bgmSource.spatialBlend = 0f;
                bgmSource.volume = 0f;
            }
        }

        private IEnumerator CrossfadeBGM(AudioClip newClip)
        {
            if (bgmSource.isPlaying)
            {
                float elapsed = 0f;
                float startVol = bgmSource.volume;
                float halfDuration = bgmFadeDuration * 0.5f;

                while (elapsed < halfDuration)
                {
                    elapsed += Time.unscaledDeltaTime;
                    bgmSource.volume = Mathf.Lerp(startVol, 0f, elapsed / halfDuration);
                    yield return null;
                }
            }

            bgmSource.clip = newClip;
            bgmSource.volume = 0f;
            bgmSource.Play();

            float fadeElapsed = 0f;
            float fadeHalf = bgmFadeDuration * 0.5f;
            while (fadeElapsed < fadeHalf)
            {
                fadeElapsed += Time.unscaledDeltaTime;
                bgmSource.volume = Mathf.Lerp(0f, bgmVolume, fadeElapsed / fadeHalf);
                yield return null;
            }
            bgmSource.volume = bgmVolume;

            _bgmFadeCoroutine = null;
        }

        private IEnumerator FadeOutBGM()
        {
            float startVol = bgmSource.volume;
            float elapsed = 0f;

            while (elapsed < bgmFadeDuration)
            {
                elapsed += Time.unscaledDeltaTime;
                bgmSource.volume = Mathf.Lerp(startVol, 0f, elapsed / bgmFadeDuration);
                yield return null;
            }

            bgmSource.Stop();
            bgmSource.volume = 0f;
            _bgmFadeCoroutine = null;
        }

        #endregion
    }
}