sharpcompress/src/SharpCompress/Readers/ReaderFactory.cs

using System;
using System.IO;
using System.Linq;
using SharpCompress.Common;
using SharpCompress.Factories;
using SharpCompress.IO;

namespace SharpCompress.Readers;

public static partial class ReaderFactory
{
    public static IReader OpenReader(string filePath, ReaderOptions? options = null)
    {
        filePath.NotNullOrEmpty(nameof(filePath));
        return OpenReader(new FileInfo(filePath), options);
    }

    public static IReader OpenReader(FileInfo fileInfo, ReaderOptions? options = null)
    {
        options ??= ReaderOptions.ForOwnedFile;
        return OpenReader(fileInfo.OpenRead(), options);
    }

    /// <summary>
    /// Opens a Reader for Non-seeking usage
    /// </summary>
    /// <param name="stream"></param>
    /// <param name="options"></param>
    /// <returns></returns>
    public static IReader OpenReader(Stream stream, ReaderOptions? options = null)
    {
        stream.NotNull(nameof(stream));
        options ??= ReaderOptions.ForExternalStream;

        var sharpCompressStream = SharpCompressStream.Create(
            stream,
            bufferSize: options.RewindableBufferSize
        );
        sharpCompressStream.StartRecording();

        var factories = Factories.Factory.Factories.OfType<Factories.Factory>();

        Factory? testedFactory = null;

        if (!string.IsNullOrWhiteSpace(options.ExtensionHint))
        {
            testedFactory = factories.FirstOrDefault(a =>
                a.GetSupportedExtensions()
                    .Contains(options.ExtensionHint, StringComparer.CurrentCultureIgnoreCase)
            );
            if (
                testedFactory?.TryOpenReader(sharpCompressStream, options, out var reader) == true
                && reader != null
            )
            {
                sharpCompressStream.Rewind(true);
                return reader;
            }
        }

        foreach (var factory in factories)
        {
            if (testedFactory == factory)
            {
                continue; // Already tested above
            }
            sharpCompressStream.Rewind();
            if (
                factory.TryOpenReader(sharpCompressStream, options, out var reader)
                && reader != null
            )
            {
                return reader;
            }
        }

        throw new InvalidFormatException(
            "Cannot determine compressed stream type.  Supported Reader Formats: Ace, Arc, Arj, Zip, GZip, BZip2, Tar, Rar, LZip, Lzw, XZ, ZStandard"
        );
    }
}