using System;
using System.Collections.Generic;
using System.IO;
using Core;
using UnityEngine;
using SDev;
using ScreenUtils = Utils.ScreenSpaceUtility;

namespace Minigames.StatueDressup.Utils
{
    /// <summary>
    /// Manages statue photo capture, storage, and retrieval.
    /// Supports area-limited screenshots, persistent file storage (mobile + PC),
    /// and optimized gallery loading with pagination.
    /// </summary>
    public static class StatuePhotoManager
    {
        private const string PhotoFolder = "StatuePhotos";
        private const string PhotoPrefix = "MrCementStatue_";
        private const string MetadataKeyPrefix = "StatuePhoto_Meta_";
        private const string PhotoIndexKey = "StatuePhoto_Index";
        
        /// <summary>
        /// Photo metadata stored in PlayerPrefs
        /// </summary>
        [Serializable]
        public class PhotoMetadata
        {
            public string photoId;
            public string timestamp;
            public int decorationCount;
            public long fileSizeBytes;
        }
        
        #region Capture
        
        /// <summary>
        /// Capture a specific area of the screen using Screenshot Helper
        /// </summary>
        /// <param name="captureArea">RectTransform defining the capture region</param>
        /// <param name="onComplete">Callback with captured Texture2D</param>
        /// <param name="mainCamera">Camera used for coordinate conversion (null = Camera.main)</param>
        /// <param name="clampToScreenBounds">If true, clamps capture area to visible screen bounds</param>
        public static void CaptureAreaPhoto(
            RectTransform captureArea, 
            Action<Texture2D> onComplete, 
            Camera mainCamera = null,
            bool clampToScreenBounds = true)
        {
            if (captureArea == null)
            {
                Logging.Error("[StatuePhotoManager] CaptureArea RectTransform is null!");
                onComplete?.Invoke(null);
                return;
            }
            
            if (mainCamera == null) mainCamera = Camera.main;
            
            // Use ScreenSpaceUtility to convert RectTransform to screen rect
            // returnCenterPosition = true because ScreenshotHelper expects center position
            Rect screenRect = ScreenUtils.RectTransformToScreenRect(
                captureArea, 
                mainCamera, 
                clampToScreenBounds,
                returnCenterPosition: true
            );
            
            Logging.Debug($"[StatuePhotoManager] Capturing area: pos={screenRect.position}, size={screenRect.size}");
            
            // Use Screenshot Helper's Capture method
            ScreenshotHelper.Instance.Capture(
                screenRect.position,
                screenRect.size,
                (texture) =>
                {
                    if (texture != null)
                    {
                        Logging.Debug($"[StatuePhotoManager] Photo captured: {texture.width}x{texture.height}");
                        onComplete?.Invoke(texture);
                    }
                    else
                    {
                        Logging.Error("[StatuePhotoManager] Screenshot Helper returned null texture!");
                        onComplete?.Invoke(null);
                    }
                }
            );
        }

        
        #endregion
        
        #region Save/Load
        
        /// <summary>
        /// Save photo to persistent storage with metadata
        /// </summary>
        /// <param name="photo">Texture2D to save</param>
        /// <param name="decorationCount">Number of decorations placed (for metadata)</param>
        /// <returns>Photo ID if successful, null if failed</returns>
        public static string SavePhoto(Texture2D photo, int decorationCount = 0)
        {
            if (photo == null)
            {
                Logging.Error("[StatuePhotoManager] Cannot save null photo");
                return null;
            }
            
            try
            {
                // Generate unique photo ID
                string photoId = $"{PhotoPrefix}{DateTime.Now.Ticks}";
                
                // Save texture using FileSaveUtil
                string savedPath = FileSaveUtil.Instance.SaveTextureAsPNG(
                    photo,
                    FileSaveUtil.AppPath.PersistentDataPath,
                    PhotoFolder,
                    photoId
                );
                
                // Calculate file size
                FileInfo fileInfo = new FileInfo(savedPath);
                long fileSize = fileInfo.Exists ? fileInfo.Length : 0;
                
                // Save metadata
                PhotoMetadata metadata = new PhotoMetadata
                {
                    photoId = photoId,
                    timestamp = DateTime.Now.ToString("o"),
                    decorationCount = decorationCount,
                    fileSizeBytes = fileSize
                };
                
                SaveMetadata(metadata);
                AddToPhotoIndex(photoId);
                
                Logging.Debug($"[StatuePhotoManager] Photo saved: {savedPath} ({fileSize} bytes)");
                return photoId;
            }
            catch (Exception e)
            {
                Logging.Error($"[StatuePhotoManager] Failed to save photo: {e.Message}");
                return null;
            }
        }
        
        /// <summary>
        /// Load photo texture from storage
        /// </summary>
        public static Texture2D LoadPhoto(string photoId)
        {
            if (string.IsNullOrEmpty(photoId))
            {
                Logging.Warning("[StatuePhotoManager] PhotoId is null or empty");
                return null;
            }
            
            try
            {
                string filePath = GetPhotoFilePath(photoId);
                
                if (!File.Exists(filePath))
                {
                    Logging.Warning($"[StatuePhotoManager] Photo not found: {filePath}");
                    return null;
                }
                
                byte[] fileData = File.ReadAllBytes(filePath);
                Texture2D texture = new Texture2D(2, 2, TextureFormat.RGBA32, false);
                
                if (texture.LoadImage(fileData))
                {
                    Logging.Debug($"[StatuePhotoManager] Photo loaded: {photoId} ({texture.width}x{texture.height})");
                    return texture;
                }
                else
                {
                    Logging.Error($"[StatuePhotoManager] Failed to decode image: {photoId}");
                    UnityEngine.Object.Destroy(texture);
                    return null;
                }
            }
            catch (Exception e)
            {
                Logging.Error($"[StatuePhotoManager] Failed to load photo {photoId}: {e.Message}");
                return null;
            }
        }
        
        /// <summary>
        /// Delete photo and its metadata
        /// </summary>
        public static bool DeletePhoto(string photoId)
        {
            if (string.IsNullOrEmpty(photoId)) return false;
            
            try
            {
                string filePath = GetPhotoFilePath(photoId);
                
                if (File.Exists(filePath))
                {
                    File.Delete(filePath);
                }
                
                DeleteMetadata(photoId);
                RemoveFromPhotoIndex(photoId);
                
                Logging.Debug($"[StatuePhotoManager] Photo deleted: {photoId}");
                return true;
            }
            catch (Exception e)
            {
                Logging.Error($"[StatuePhotoManager] Failed to delete photo {photoId}: {e.Message}");
                return false;
            }
        }
        
        #endregion
        
        #region Gallery Support
        
        /// <summary>
        /// Get all photo IDs sorted by timestamp (newest first)
        /// </summary>
        public static List<string> GetAllPhotoIds()
        {
            string indexJson = PlayerPrefs.GetString(PhotoIndexKey, "[]");
            List<string> photoIds = JsonUtility.FromJson<PhotoIdList>(WrapJsonArray(indexJson))?.ids ?? new List<string>();
            
            // Sort by timestamp descending (newest first)
            photoIds.Sort((a, b) =>
            {
                PhotoMetadata metaA = LoadMetadata(a);
                PhotoMetadata metaB = LoadMetadata(b);
                
                DateTime dateA = DateTime.Parse(metaA?.timestamp ?? DateTime.MinValue.ToString("o"));
                DateTime dateB = DateTime.Parse(metaB?.timestamp ?? DateTime.MinValue.ToString("o"));
                
                return dateB.CompareTo(dateA);
            });
            
            return photoIds;
        }
        
        /// <summary>
        /// Get paginated photo IDs for optimized gallery loading
        /// </summary>
        /// <param name="page">Page number (0-indexed)</param>
        /// <param name="pageSize">Number of items per page</param>
        public static List<string> GetPhotoIdsPage(int page, int pageSize)
        {
            List<string> allIds = GetAllPhotoIds();
            int startIndex = page * pageSize;
            
            if (startIndex >= allIds.Count) return new List<string>();
            
            int count = Mathf.Min(pageSize, allIds.Count - startIndex);
            return allIds.GetRange(startIndex, count);
        }
        
        /// <summary>
        /// Get total number of saved photos
        /// </summary>
        public static int GetPhotoCount()
        {
            return GetAllPhotoIds().Count;
        }
        
        /// <summary>
        /// Get latest photo ID (most recent)
        /// </summary>
        public static string GetLatestPhotoId()
        {
            List<string> allIds = GetAllPhotoIds();
            return allIds.Count > 0 ? allIds[0] : null;
        }
        
        /// <summary>
        /// Load photo metadata
        /// </summary>
        public static PhotoMetadata GetPhotoMetadata(string photoId)
        {
            return LoadMetadata(photoId);
        }
        
        /// <summary>
        /// Create thumbnail from full-size photo (for gallery preview)
        /// </summary>
        public static Texture2D CreateThumbnail(Texture2D fullSizePhoto, int maxSize = 256)
        {
            if (fullSizePhoto == null) return null;
            
            int width = fullSizePhoto.width;
            int height = fullSizePhoto.height;
            
            // Calculate thumbnail size maintaining aspect ratio
            float scale = Mathf.Min((float)maxSize / width, (float)maxSize / height);
            int thumbWidth = Mathf.RoundToInt(width * scale);
            int thumbHeight = Mathf.RoundToInt(height * scale);
            
            // Create thumbnail using bilinear filtering
            RenderTexture rt = RenderTexture.GetTemporary(thumbWidth, thumbHeight, 0, RenderTextureFormat.ARGB32);
            RenderTexture.active = rt;
            
            Graphics.Blit(fullSizePhoto, rt);
            
            Texture2D thumbnail = new Texture2D(thumbWidth, thumbHeight, TextureFormat.RGB24, false);
            thumbnail.ReadPixels(new Rect(0, 0, thumbWidth, thumbHeight), 0, 0);
            thumbnail.Apply();
            
            RenderTexture.active = null;
            RenderTexture.ReleaseTemporary(rt);
            
            return thumbnail;
        }
        
        #endregion
        
        #region Internal Helpers

        public static string GetPhotoDirectory()
        {
            return Path.Combine(Application.persistentDataPath, PhotoFolder);
        }
        
        private static string GetPhotoFilePath(string photoId)
        {
            return Path.Combine(GetPhotoDirectory(), $"{photoId}.png");
        }
        
        private static void SaveMetadata(PhotoMetadata metadata)
        {
            string json = JsonUtility.ToJson(metadata);
            PlayerPrefs.SetString(MetadataKeyPrefix + metadata.photoId, json);
            PlayerPrefs.Save();
        }
        
        private static PhotoMetadata LoadMetadata(string photoId)
        {
            string json = PlayerPrefs.GetString(MetadataKeyPrefix + photoId, null);
            return string.IsNullOrEmpty(json) ? null : JsonUtility.FromJson<PhotoMetadata>(json);
        }
        
        private static void DeleteMetadata(string photoId)
        {
            PlayerPrefs.DeleteKey(MetadataKeyPrefix + photoId);
            PlayerPrefs.Save();
        }
        
        private static void AddToPhotoIndex(string photoId)
        {
            List<string> photoIds = GetAllPhotoIds();
            if (!photoIds.Contains(photoId))
            {
                photoIds.Add(photoId);
                SavePhotoIndex(photoIds);
            }
        }
        
        private static void RemoveFromPhotoIndex(string photoId)
        {
            List<string> photoIds = GetAllPhotoIds();
            if (photoIds.Remove(photoId))
            {
                SavePhotoIndex(photoIds);
            }
        }
        
        private static void SavePhotoIndex(List<string> photoIds)
        {
            string json = JsonUtility.ToJson(new PhotoIdList { ids = photoIds });
            PlayerPrefs.SetString(PhotoIndexKey, json);
            PlayerPrefs.Save();
        }
        
        private static string WrapJsonArray(string json)
        {
            if (json.StartsWith("[")) return "{\"ids\":" + json + "}";
            return json;
        }
        
        [Serializable]
        private class PhotoIdList
        {
            public List<string> ids = new List<string>();
        }
        
        #endregion
    }
}