using System;
using System.Collections;
using AibisDream.Framework;
using AibisDream.Kit;
using AibisDream.Utility;
using DG.Tweening;
using UnityEngine;
using UnityEngine.ResourceManagement.AsyncOperations;

namespace AibisDream
{
    public class SpriteShowcase : Singleton<SpriteShowcase>
    {
        /// <summary>Addressable Key 模板，与 Scene_Dream 中梦境图 Address 一致。</summary>
        private const string DreamSpritePath = "Sprite/梦境/{0}.png";

        [SerializeField] private SpriteRenderer _spriteRenderer;
        [SerializeField] private SpriteRenderer _backgroundSpriteRenderer;
        [SerializeField] private SpriteRenderer _largeSpriteRenderer;

        // 通过 activeSelf 判断当前状态
        private bool IsSmallShowing => _spriteRenderer.gameObject.activeSelf;
        private bool IsLargeShowing => _largeSpriteRenderer != null && _largeSpriteRenderer.gameObject.activeSelf;

        public override void OnSingletonInit()
        {
            // 初始状态：隐藏
            _spriteRenderer.gameObject.SetActive(false);
            _spriteRenderer.SetAlpha(0);

            // 大图初始状态：隐藏
            if (_largeSpriteRenderer != null)
            {
                _largeSpriteRenderer.gameObject.SetActive(false);
                _largeSpriteRenderer.SetAlpha(0);
            }
        }

        private static string NormalizeDreamPicName(string picName)
        {
            if (string.IsNullOrEmpty(picName)) return picName;
            return picName.EndsWith(".png", StringComparison.OrdinalIgnoreCase)
                ? picName.Substring(0, picName.Length - 4)
                : picName;
        }

        private IEnumerator LoadDreamSpriteInto(SpriteRenderer target, string picName)
        {
            var key = string.Format(DreamSpritePath, NormalizeDreamPicName(picName));
            var handle = ResourceSystem.LoadAsync<Sprite>(key);
            yield return handle;
            if (handle.Status == AsyncOperationStatus.Succeeded && handle.Result != null)
                target.sprite = handle.Result;
            else
                Debug.LogError($"[SpriteShowcase] Failed to load sprite: {key}");
        }

        /// <summary>
        /// 显示物体（小图）
        /// </summary>
        /// <param name="picName">图片名（无扩展名，与 Yarn 中一致；Addressable Key 由 <see cref="DreamSpritePath"/> 拼接）</param>
        /// <param name="duration">淡入时长</param>
        /// <returns>协程</returns>
        public IEnumerator ShowObj(string picName, float duration = 1)
        {
            // 互斥：如果大图正在显示，先隐藏
            if (IsLargeShowing)
            {
                yield return HideLargeObj(duration);
            }

            _spriteRenderer.gameObject.SetActive(true);

            yield return LoadDreamSpriteInto(_spriteRenderer, picName);

            yield return _spriteRenderer.DOFade(1, duration).WaitForCompletion();
        }

        /// <summary>
        /// 显示大图
        /// </summary>
        /// <param name="picName">图片名（无扩展名，与 Yarn 中一致；Addressable Key 由 <see cref="DreamSpritePath"/> 拼接）</param>
        /// <param name="duration">淡入时长</param>
        /// <returns>协程</returns>
        public IEnumerator ShowLargeObj(string picName, float duration = 1)
        {
            // 互斥：如果小图正在显示，先隐藏
            if (IsSmallShowing)
            {
                yield return HideObj(duration);
            }

            if (_largeSpriteRenderer == null) yield break;

            _largeSpriteRenderer.gameObject.SetActive(true);

            yield return LoadDreamSpriteInto(_largeSpriteRenderer, picName);

            yield return _largeSpriteRenderer.DOFade(1, duration).WaitForCompletion();
        }

        /// <summary>
        /// 隐藏物体（小图）
        /// </summary>
        /// <param name="duration">淡出时长</param>
        /// <returns>协程</returns>
        public IEnumerator HideObj(float duration = 1)
        {
            yield return HideObj(force: false, duration);
        }

        /// <summary>
        /// 隐藏物体（小图）
        /// </summary>
        /// <param name="force">是否强制隐藏</param>
        /// <param name="duration">淡出时长</param>
        /// <returns>协程</returns>
        public IEnumerator HideObj(bool force, float duration = 1)
        {
            // force=false 时检查状态，未显示则直接返回
            if (!force && !IsSmallShowing) yield break;

            yield return _spriteRenderer.DOFade(0, duration).WaitForCompletion();
            _spriteRenderer.gameObject.SetActive(false);
        }
        
        /// <summary>
        /// 隐藏大图
        /// </summary>
        /// <param name="force">是否强制隐藏</param>
        /// <param name="duration">淡出时长</param>
        /// <returns>协程</returns>
        public IEnumerator HideLargeObj(float duration = 1)
        {
            if (_largeSpriteRenderer == null) yield break;

            yield return _largeSpriteRenderer.DOFade(0, duration).WaitForCompletion();
            _largeSpriteRenderer.gameObject.SetActive(false);
        }

        /// <summary>
        /// 隐藏所有（小图和大图）
        /// </summary>
        /// <param name="duration">淡出时长</param>
        /// <returns>协程</returns>
        public IEnumerator HideAll(float duration = 1)
        {
            if (IsSmallShowing)
                yield return HideObj(duration);

            if (IsLargeShowing)
                yield return HideLargeObj(duration);
        }

        /// <summary>
        /// 淡入（异步协程版本）
        /// </summary>
        /// <param name="duration">淡入时长</param>
        /// <returns>协程</returns>
        public IEnumerator FadeInAsync(float duration = 1)
        {
            if (_backgroundSpriteRenderer == null) yield break;
            
            _backgroundSpriteRenderer.gameObject.SetActive(true);
            yield return _backgroundSpriteRenderer.DOFade(1, duration).WaitForCompletion();
        }

        /// <summary>
        /// 淡出（异步协程版本）
        /// </summary>
        /// <param name="duration">淡出时长</param>
        /// <returns>协程</returns>
        public IEnumerator FadeOutAsync(float duration = 1)
        {
            if (_backgroundSpriteRenderer == null) yield break;
            
            _backgroundSpriteRenderer.gameObject.SetActive(true);
            yield return _backgroundSpriteRenderer.DOFade(0, duration).WaitForCompletion();
            _backgroundSpriteRenderer.gameObject.SetActive(false);
        }

        /// <summary>
        /// 淡入（同步版本，启动协程）
        /// </summary>
        /// <param name="duration">淡入时长</param>
        public void FadeInSync(float duration = 1)
        {
            StartCoroutine(FadeInAsync(duration));
        }

        /// <summary>
        /// 淡出（同步版本，启动协程）
        /// </summary>
        /// <param name="duration">淡出时长</param>
        public void FadeOutSync(float duration = 1)
        {
            StartCoroutine(FadeOutAsync(duration));
        }
    }
}