rokojori_action_library/Tools/mcp/VariantJson.cs

#if TOOLS

using Godot;

namespace Rokojori.Tools
{
  using Rokojori;

  // Two-way mapping between Godot Variant and the addon's own JSON types.
  // Sub-resources are referenced by resource_path; an embedded sub-resource with
  // no saved path round-trips as a tagged placeholder rather than its real data -
  // not needed by the first 4 routes, revisit if a fragment ever needs it.
  public static class VariantJson
  {
    public static JSONData ToJson( Variant v )
    {
      switch ( v.VariantType )
      {
        case Variant.Type.Nil:
          return new JSONValue();

        case Variant.Type.Bool:
          return new JSONValue( v.AsBool() );

        case Variant.Type.Int:
          return new JSONValue( (double) v.AsInt64() );

        case Variant.Type.Float:
          return new JSONValue( v.AsDouble() );

        case Variant.Type.String:
        case Variant.Type.StringName:
          return new JSONValue( v.AsString() );

        case Variant.Type.NodePath:
          return new JSONValue( v.AsNodePath().ToString() );

        case Variant.Type.Vector2:
          return Vector2ToJson( v.AsVector2() );

        case Variant.Type.Vector2I:
          var v2i = v.AsVector2I();
          return Vector2ToJson( new Vector2( v2i.X, v2i.Y ) );

        case Variant.Type.Vector3:
          return Vector3ToJson( v.AsVector3() );

        case Variant.Type.Vector3I:
          var v3i = v.AsVector3I();
          return Vector3ToJson( new Vector3( v3i.X, v3i.Y, v3i.Z ) );

        case Variant.Type.Vector4:
          return Vector4ToJson( v.AsVector4() );

        case Variant.Type.Color:
          return ColorToJson( v.AsColor() );

        case Variant.Type.Array:
          return ArrayToJson( v.AsGodotArray() );

        case Variant.Type.Dictionary:
          return DictionaryToJson( v.AsGodotDictionary() );

        case Variant.Type.Object:
          return ObjectToJson( v.AsGodotObject() );

        default:
          // Not modeled explicitly (Rid, Callable, Signal, Transform*, Basis, Plane, Quaternion, Projection, Aabb, Rect2...).
          // Falls back to a readable string so round-tripping these doesn't crash - just loses write support.
          return new JSONValue( v.ToString() );
      }
    }

    public static Variant FromJson( JSONData data, Variant.Type targetType )
    {
      if ( data == null || data.isNull )
      {
        return new Variant();
      }

      switch ( targetType )
      {
        case Variant.Type.Nil:
          // Untyped [Export] Variant field - no declared type to convert against, shape-sniff instead.
          return FromJsonInferred( data );

        case Variant.Type.Bool:
          return data.booleanValue;

        case Variant.Type.Int:
          return data.longValue;

        case Variant.Type.Float:
          return data.numberValue;

        case Variant.Type.String:
          return data.stringValue;

        case Variant.Type.StringName:
          return new StringName( data.stringValue );

        case Variant.Type.NodePath:
          return new NodePath( data.stringValue );

        case Variant.Type.Vector2:
          return JsonToVector2( data.AsObject() );

        case Variant.Type.Vector2I:
          var v2 = JsonToVector2( data.AsObject() );
          return new Vector2I( (int) v2.X, (int) v2.Y );

        case Variant.Type.Vector3:
          return JsonToVector3( data.AsObject() );

        case Variant.Type.Vector3I:
          var v3 = JsonToVector3( data.AsObject() );
          return new Vector3I( (int) v3.X, (int) v3.Y, (int) v3.Z );

        case Variant.Type.Vector4:
          return JsonToVector4( data.AsObject() );

        case Variant.Type.Color:
          return JsonToColor( data.AsObject() );

        case Variant.Type.Array:
          return JsonToArray( data.AsArray() );

        case Variant.Type.Dictionary:
          return JsonToDictionary( data.AsObject() );

        case Variant.Type.Object:
          return JsonToResource( data.AsObject() );

        default:
          RJLog.Error( "MCP VariantJson: write not supported for Variant type", targetType );
          return new Variant();
      }
    }

    // Used for Array/Dictionary element values, which have no declared Variant type of their own -
    // shape-sniffs the JSON (keys x/y/z/w, r/g/b/a, __resourcePath) rather than a real type lookup.
    public static Variant FromJsonInferred( JSONData data )
    {
      if ( data == null || data.isNull )
      {
        return new Variant();
      }

      if ( data.isBoolean )
      {
        return data.booleanValue;
      }

      if ( data.isNumber )
      {
        return data.numberValue;
      }

      if ( data.isString )
      {
        return data.stringValue;
      }

      if ( data.isArray )
      {
        return JsonToArray( data.AsArray() );
      }

      if ( data.isObject )
      {
        var obj = data.AsObject();

        if ( obj.Contains( "__resourcePath" ) )
        {
          return JsonToResource( obj );
        }

        if ( obj.Contains( "x" ) && obj.Contains( "y" ) && obj.Contains( "z" ) && obj.Contains( "w" ) )
        {
          return JsonToVector4( obj );
        }

        if ( obj.Contains( "r" ) && obj.Contains( "g" ) && obj.Contains( "b" ) )
        {
          return JsonToColor( obj );
        }

        if ( obj.Contains( "x" ) && obj.Contains( "y" ) && obj.Contains( "z" ) )
        {
          return JsonToVector3( obj );
        }

        if ( obj.Contains( "x" ) && obj.Contains( "y" ) )
        {
          return JsonToVector2( obj );
        }

        return JsonToDictionary( obj );
      }

      return new Variant();
    }

    public static JSONObject Vector2ToJson( Vector2 v )
    {
      var o = new JSONObject();
      o.Set( "x", (double) v.X );
      o.Set( "y", (double) v.Y );
      return o;
    }

    public static JSONObject Vector3ToJson( Vector3 v )
    {
      var o = new JSONObject();
      o.Set( "x", (double) v.X );
      o.Set( "y", (double) v.Y );
      o.Set( "z", (double) v.Z );
      return o;
    }

    public static JSONObject Vector4ToJson( Vector4 v )
    {
      var o = new JSONObject();
      o.Set( "x", (double) v.X );
      o.Set( "y", (double) v.Y );
      o.Set( "z", (double) v.Z );
      o.Set( "w", (double) v.W );
      return o;
    }

    public static JSONObject ColorToJson( Color c )
    {
      var o = new JSONObject();
      o.Set( "r", (double) c.R );
      o.Set( "g", (double) c.G );
      o.Set( "b", (double) c.B );
      o.Set( "a", (double) c.A );
      return o;
    }

    public static Vector2 JsonToVector2( JSONObject o )
    {
      if ( o == null ) return Vector2.Zero;
      return new Vector2( (float) o.GetNumberOr( "x", 0 ), (float) o.GetNumberOr( "y", 0 ) );
    }

    public static Vector3 JsonToVector3( JSONObject o )
    {
      if ( o == null ) return Vector3.Zero;
      return new Vector3( (float) o.GetNumberOr( "x", 0 ), (float) o.GetNumberOr( "y", 0 ), (float) o.GetNumberOr( "z", 0 ) );
    }

    public static Vector4 JsonToVector4( JSONObject o )
    {
      if ( o == null ) return Vector4.Zero;
      return new Vector4( (float) o.GetNumberOr( "x", 0 ), (float) o.GetNumberOr( "y", 0 ), (float) o.GetNumberOr( "z", 0 ), (float) o.GetNumberOr( "w", 0 ) );
    }

    public static Color JsonToColor( JSONObject o )
    {
      if ( o == null ) return Colors.White;
      return new Color(
        (float) o.GetNumberOr( "r", 1 ), (float) o.GetNumberOr( "g", 1 ),
        (float) o.GetNumberOr( "b", 1 ), (float) o.GetNumberOr( "a", 1 )
      );
    }

    public static JSONArray ArrayToJson( Godot.Collections.Array array )
    {
      var result = new JSONArray();

      foreach ( var item in array )
      {
        result.Push( ToJson( item ) );
      }

      return result;
    }

    public static Godot.Collections.Array JsonToArray( JSONArray array )
    {
      var result = new Godot.Collections.Array();

      if ( array == null )
      {
        return result;
      }

      foreach ( var item in array.values )
      {
        result.Add( FromJsonInferred( item ) );
      }

      return result;
    }

    public static JSONObject DictionaryToJson( Godot.Collections.Dictionary dict )
    {
      var result = new JSONObject();

      foreach ( var key in dict.Keys )
      {
        result.Set( key.AsString(), ToJson( dict[ key ] ) );
      }

      return result;
    }

    public static Godot.Collections.Dictionary JsonToDictionary( JSONObject o )
    {
      var result = new Godot.Collections.Dictionary();

      if ( o == null )
      {
        return result;
      }

      for ( var i = 0; i < o.keys.Count; i++ )
      {
        result[ o.keys[ i ] ] = FromJsonInferred( o.values[ i ] );
      }

      return result;
    }

    public static JSONData ObjectToJson( GodotObject obj )
    {
      if ( obj == null )
      {
        return new JSONValue();
      }

      var wrapper = new JSONObject();

      if ( obj is Resource resource )
      {
        if ( ! string.IsNullOrEmpty( resource.ResourcePath ) )
        {
          wrapper.Set( "__resourcePath", resource.ResourcePath );
        }
        else
        {
          wrapper.Set( "__embeddedResourceType", resource.GetClass() );
        }

        return wrapper;
      }

      return new JSONValue( obj.ToString() );
    }

    public static Resource JsonToResource( JSONObject o )
    {
      if ( o == null || ! o.Contains( "__resourcePath" ) )
      {
        return null;
      }

      var path = o.GetString( "__resourcePath" );
      return ResourceLoader.Load( path );
    }
  }
}

#endif