using System;
using System.IO;
using System.Text;

namespace UnityFS
{
    public static class BinaryWriterExtensions
    {
        public static void AlignStream(this BinaryWriter writer, int alignment)
        {
            var pos = writer.BaseStream.Position;
            var mod = pos % alignment;
            if (mod != 0)
            {
                writer.Write(new byte[alignment - mod]);
            }
        }

        public static void WriteAlignedString(this BinaryWriter writer, string str)
        {
            var bytes = Encoding.UTF8.GetBytes(str);
            writer.Write(bytes.Length);
            writer.Write(bytes);
            writer.AlignStream(4);
        }

        public static void WriteNullEndString(this BinaryWriter writer, string str)
        {
            writer.Write(Encoding.UTF8.GetBytes(str));
            writer.Write((byte)0);
        }
    }
}