using UnityEngine;
using UnityEditor;
using System.IO;

public class BlockDataIconLinker : AssetPostprocessor
{
    // Fires after any assets are imported
    static void OnPostprocessAllAssets(
        string[] importedAssets,
        string[] deletedAssets,
        string[] movedAssets,
        string[] movedFromAssetPaths)
    {
        foreach (string assetPath in importedAssets)
        {
            // Only care about Texture2D PNGs
            if (!assetPath.EndsWith(".png", System.StringComparison.OrdinalIgnoreCase))
                continue;

            Texture2D texture = AssetDatabase.LoadAssetAtPath<Texture2D>(assetPath);
            if (texture == null) continue;

            // Try to find a matching BlockData for this texture
            TryLinkToBlockData(texture, assetPath);
        }
    }

    private static void TryLinkToBlockData(Texture2D texture, string texturePath)
    {
        string textureName = Path.GetFileNameWithoutExtension(texturePath);

        // Find all BlockData assets in the project
        string[] guids = AssetDatabase.FindAssets("t:BlockData");
        foreach (string guid in guids)
        {
            string blockDataPath = AssetDatabase.GUIDToAssetPath(guid);
            BlockData blockData = AssetDatabase.LoadAssetAtPath<BlockData>(blockDataPath);

            if (blockData == null || blockData.blockPrefab == null) continue;

            // Match by checking if the texture name contains the prefab name
            // Handles prefixes/suffixes like "Icon_zPin", "Icon_zPin_v2", etc.
            if (!textureName.Contains(blockData.blockPrefab.name)) continue;

            // Skip if already assigned to avoid unnecessary reimports
            if (blockData.icon == texture || blockData.icon != null) continue;

            blockData.icon = texture;
            EditorUtility.SetDirty(blockData);
            AssetDatabase.SaveAssetIfDirty(blockData);

            Debug.Log($"[BlockDataIconLinker] Linked '{texturePath}' → '{blockDataPath}'");
        }
    }
}