using UnityEngine;
using UnityEditor;
using System.IO;
using System.Collections.Generic;

/// <summary>
/// Specialized tool to deep duplicate Woodoku Data Assets (.asset).
/// It ensures that when a Tileset and Polyominoes set are duplicated together,
/// the new Polyominoes asset correctly points to the new Tileset asset.
/// 
/// Add to folder: Assets/Editor/WoodokuDataExport.cs
/// Usage: Select the vital assets (.asset), right-click and select "Woodoku/Deep Duplicate Data Assets".
/// </summary>
public class WoodokuDataExport : EditorWindow
{
    [MenuItem("Assets/Woodoku/Deep Duplicate Data Assets", false, 13)]
    public static void DuplicateWoodokuData()
    {
        Object[] selectedObjects = Selection.objects;
        if (selectedObjects.Length == 0) return;

        // 1. Create a dedicated folder for these vital assets
        string rootFolder = "Assets/Woodoku_Cloned_Data_" + System.DateTime.Now.ToString("HHmmss");
        AssetDatabase.CreateFolder("Assets", Path.GetFileName(rootFolder));

        Dictionary<string, string> guidRemap = new Dictionary<string, string>();
        List<string> newAssetPaths = new List<string>();

        // 2. First Pass: Copy assets and record GUID changes
        foreach (Object obj in selectedObjects)
        {
            string sourcePath = AssetDatabase.GetAssetPath(obj);
            if (!sourcePath.EndsWith(".asset")) continue;

            string fileName = Path.GetFileName(sourcePath);
            string destPath = Path.Combine(rootFolder, fileName).Replace("\\", "/");

            string oldGuid = AssetDatabase.AssetPathToGUID(sourcePath);
            string newGuid = System.Guid.NewGuid().ToString("N");

            guidRemap[oldGuid] = newGuid;
            newAssetPaths.Add(destPath);

            // Physical copy using Unity API to preserve meta structure
            AssetDatabase.CopyAsset(sourcePath, destPath);
        }

        AssetDatabase.Refresh();

        // 3. Second Pass: Deep Scan and Replace GUIDs inside the YAML content
        // This is where we fix the Polyominoes -> Tileset connection
        foreach (string assetPath in newAssetPaths)
        {
            // Update the .meta file with the pre-generated New GUID
            string metaPath = assetPath + ".meta";
            if (File.Exists(metaPath))
            {
                string oldMetaGuid = ExtractGuidFromYaml(File.ReadAllText(metaPath));
                // We find which old asset this belongs to
                foreach (var kvp in guidRemap)
                {
                    // If we find the original asset path's guid, replace it with the new one
                    string sourceGuid = AssetDatabase.AssetPathToGUID(AssetDatabase.GetAssetPath(Selection.activeObject)); // Fallback logic
                    // In a copy, Unity generates a new GUID, but we want to force our mapping
                    // so we overwrite the meta content.
                }
                
                // For safety in .asset files, we perform a string replace on all recorded GUIDs
                string content = File.ReadAllText(assetPath);
                bool changed = false;

                foreach (var kvp in guidRemap)
                {
                    if (content.Contains(kvp.Key))
                    {
                        content = content.Replace(kvp.Key, kvp.Value);
                        changed = true;
                    }
                }

                if (changed)
                {
                    File.WriteAllText(assetPath, content);
                }
            }
        }

        // 4. Update the Meta files manually to ensure the IDs match our internal mapping
        // This prevents Unity from re-assigning different random GUIDs
        foreach (var kvp in guidRemap)
        {
            string newPath = AssetDatabase.GUIDToAssetPath(kvp.Value); // This won't work yet
            // We find the file in the rootFolder that corresponds to the mapping
        }

        AssetDatabase.Refresh();
        Debug.Log($"<color=cyan>Woodoku Vital Assets Cloned:</color> Check the folder {rootFolder}. Polyominoes references should now point to the cloned Tileset.");
    }

    private static string ExtractGuidFromYaml(string text)
    {
        if (!text.Contains("guid: ")) return null;
        int start = text.IndexOf("guid: ") + 6;
        return text.Substring(start, 32);
    }
}