using System.Text;
using PCC.App.BinaryFormatter;

namespace PCC.App.TransferModels;

public static class BlockWithNonce1
{
    public static ReadOnlyMemory<byte> Mux(ReadOnlyMemory<byte> payload, ReadOnlyMemory<byte> nonce)
    {
        // 计算总长度
        var totalLength = payload.Length + nonce.Length;
        var buffer = new byte[totalLength];

        // 将 payload 和 nonce 拷贝到 buffer 中
        payload.Span.CopyTo(buffer);
        nonce.Span.CopyTo(buffer.AsSpan(payload.Length));

        return buffer;
    }

    public static (ReadOnlyMemory<byte> payload, ReadOnlyMemory<byte> nonce) Demux(ReadOnlyMemory<byte> transferBlock, int nonceBytes)
    {
        // 计算 payload 的长度
        var payloadLength = transferBlock.Length - nonceBytes;

        // 获取 payload 和 nonce
        var payload = transferBlock.Slice(0, payloadLength);
        var nonce = transferBlock.Slice(payloadLength, nonceBytes);

        return (payload, nonce);
    }
}