// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
using System;
using System.IO;

namespace Microsoft.DotNet.Build.Tasks.Installers;

internal static class StreamHelpers
{
    public static Span<byte> ReadExactly(this Stream stream, int n)
    {
        byte[] buffer = new byte[n];
        stream.ReadExactly(buffer, 0, n);
        return buffer;
    }

    public static int AlignUp(this int value, int alignment)
    {
        return (value + alignment - 1) & ~(alignment - 1);
    }

    public static long AlignUp(this long value, int alignment)
    {
        return (value + alignment - 1) & ~(alignment - 1);
    }

    public static void AlignReadTo(this Stream stream, int alignment)
    {
        stream.Position = stream.Position.AlignUp(alignment);
    }

    public static void AlignWriteTo(this Stream stream, int alignment)
    {
        int padding = (int)(stream.Position.AlignUp(alignment) - stream.Position);
        for (int i = 0; i < padding; i++)
        {
            stream.WriteByte(0);
        }
    }
}