//////////////////////////////////////////////////////
// MicroVerse
// Copyright (c) Jason Booth
//////////////////////////////////////////////////////

using UnityEngine;
using UnityEditor;
#if UNITY_2020_2_OR_NEWER
using UnityEditor.AssetImporters;
#else
using UnityEditor.Experimental.AssetImporters;
#endif
using System.IO;

// Allows you to read/write any texture format from unity as if it's a native format.
namespace JBooth.MicroVerseCore
{
   [ScriptedImporter (1, "mvtexture")]
   public class HDTextureImporter : ScriptedImporter
   {
      public static void Write (Texture2D r, string path, bool mips, bool linear)
      {
         var filePath = path + ".mvtexture";

         if (File.Exists(filePath))
         {
             AssetDatabase.MakeEditable(filePath);
         }

         using (var bw = new BinaryWriter (File.Open (path + ".mvtexture", FileMode.OpenOrCreate)))
         {
            bw.Write (0);
            bw.Write ((int)r.format);
            bw.Write (r.width);
            bw.Write (r.height);
            bw.Write (mips);
            bw.Write (linear);

            var bytes = r.GetRawTextureData ();
            bw.Write (bytes.Length);
            bw.Write (r.GetRawTextureData ());
         }
      }

      public override void OnImportAsset (AssetImportContext ctx)
      {
         using (var r = new BinaryReader (File.Open (ctx.assetPath, FileMode.Open)))
         {
            int version = r.ReadInt32 ();
            if (version != 0)
            {
               Debug.LogError ("Version mismatch in hdtexture aseset");
               return;
            }
            TextureFormat format = (TextureFormat)r.ReadInt32 ();

            int width = r.ReadInt32 ();
            int height = r.ReadInt32 ();
            bool mips = r.ReadBoolean ();
            bool linear = r.ReadBoolean ();
            int length = r.ReadInt32 ();

            byte [] bytes = r.ReadBytes (length);
            var tex = new Texture2D (width, height, format, mips, linear);
            tex.LoadRawTextureData (bytes);
            tex.Apply ();
            ctx.AddObjectToAsset ("main obj", tex);
            ctx.SetMainObject (tex);
         }

      }
   }
}