IntegerExtensions.cs

using System.Buffers.Binary;

namespace Texnomic.Types.Extensions;

public static class IntegerExtensions
{
    extension(int Value)
    {
        public byte[] ToBytes(bool IsBigEndian = true)
        {
            var Bytes = BitConverter.GetBytes(Value);

            if (IsBigEndian && BitConverter.IsLittleEndian) Array.Reverse(Bytes);

            return Bytes;
        }

        /// <summary>Attempts to write the value as a 4-byte payload into <paramref name="Destination"/>.</summary>
        public bool TryWriteBytes(Span<byte> Destination, out int BytesWritten, bool IsBigEndian = true)
        {
            if (Destination.Length < sizeof(int))
            {
                BytesWritten = 0;
                return false;
            }

            if (IsBigEndian)
                BinaryPrimitives.WriteInt32BigEndian(Destination, Value);
            else
                BinaryPrimitives.WriteInt32LittleEndian(Destination, Value);

            BytesWritten = sizeof(int);
            return true;
        }

        public string AsHex(bool Prefixed = true) => Prefixed ? $"0x{Value:x}" : $"{Value:x}";
    }

    public static string AsHex(this uint Value, bool Prefixed = true) => Prefixed ? $"0x{Value:x}" : $"{Value:x}";

    /// <summary>Encodes an unsigned 32-bit integer as a 4-byte buffer with the requested endianness.</summary>
    public static byte[] ToBytes(this uint Value, bool IsBigEndian = true)
    {
        var Bytes = new byte[sizeof(uint)];

        if (IsBigEndian)
            BinaryPrimitives.WriteUInt32BigEndian(Bytes, Value);
        else
            BinaryPrimitives.WriteUInt32LittleEndian(Bytes, Value);

        return Bytes;
    }

    /// <summary>Attempts to write an unsigned 32-bit integer into <paramref name="Destination"/>.</summary>
    public static bool TryWriteBytes(this uint Value, Span<byte> Destination, out int BytesWritten, bool IsBigEndian = true)
    {
        if (Destination.Length < sizeof(uint))
        {
            BytesWritten = 0;
            return false;
        }

        if (IsBigEndian)
            BinaryPrimitives.WriteUInt32BigEndian(Destination, Value);
        else
            BinaryPrimitives.WriteUInt32LittleEndian(Destination, Value);

        BytesWritten = sizeof(uint);
        return true;
    }
}