class_name GRF


class Header:
	static var byte_length: int = 46
	
	## Byte Length: 15
	## Master of Magic
	var signature: String
	
	## Byte Length: 15
	var encryption: PackedByteArray
	
	## Byte Type: u32
	## Byte Length: 4
	var file_table_offset: int
	
	## Byte Type: u32
	## Byte Length: 4
	var reserved_files: int
	
	## Byte Type: u32
	## Byte Length: 4
	var file_count: int
	
	## Byte Type: u32
	## Byte Length: 4
	var version: int
	
	
	static func from_file(file: FileAccess):
		var header = Header.new()
		header.signature = file.get_buffer(15).get_string_from_utf8()
		header.encryption = file.get_buffer(15)
		header.file_table_offset = file.get_buffer(4).decode_u32(0)
		header.reserved_files = file.get_buffer(4).decode_u32(0)
		header.file_count = file.get_buffer(4).decode_u32(0)
		header.version = file.get_buffer(4).decode_u32(0)
		
		return header