wabbajack/Wabbajack.Compression.BSA/BSADispatch.cs

using System;
using System.IO;
using System.Threading.Tasks;
using Wabbajack.Common;
using Wabbajack.Common.FileSignatures;
using Wabbajack.Compression.BSA.Interfaces;
using Wabbajack.Compression.BSA.TES3Archive;
using Wabbajack.DTOs.BSA.ArchiveStates;
using Wabbajack.DTOs.Streams;
using Wabbajack.Paths;
using Wabbajack.Paths.IO;

namespace Wabbajack.Compression.BSA
{
    public static class BSADispatch
    {
        private static readonly SignatureChecker BSASignatures = new(FileType.BSA, FileType.BA2, FileType.TES3);

        public static async ValueTask<IReader> Open(AbsolutePath filename)
        {
            return await BSASignatures.MatchesAsync(filename) switch
            {
                FileType.TES3 => await Reader.Load(new NativeFileStreamFactory(filename)),
                FileType.BSA => await TES5Archive.Reader.Load(new NativeFileStreamFactory(filename)),
                FileType.BA2 => await FO4Archive.Reader.Load(new NativeFileStreamFactory(filename)),
                _ => throw new InvalidDataException("Filename is not a .bsa or .ba2")
            };
        }

        public static async ValueTask<IReader> Open(IStreamFactory factory)
        {
            await using var stream = await factory.GetStream();
            return await BSASignatures.MatchesAsync(stream) switch
            {
                FileType.TES3 => await Reader.Load(factory),
                FileType.BSA => await TES5Archive.Reader.Load(factory),
                FileType.BA2 => await FO4Archive.Reader.Load(factory),
                _ => throw new InvalidDataException("Filename is not a .bsa or .ba2")
            };
        }

        public static async ValueTask<IReader> Open(IStreamFactory factory, FileType sig)
        {
            await using var stream = await factory.GetStream();
            return sig switch
            {
                FileType.TES3 => await Reader.Load(factory),
                FileType.BSA => await TES5Archive.Reader.Load(factory),
                FileType.BA2 => await FO4Archive.Reader.Load(factory),
                _ => throw new InvalidDataException("Filename is not a .bsa or .ba2")
            };
        }

        public static IBuilder CreateBuilder(IArchive oldState, TemporaryFileManager manager)
        {
            return oldState switch
            {
                TES3State tes3 => new Builder(tes3),
                BSAState bsa => TES5Archive.Builder.Create(bsa, manager),
                BA2State ba2 => FO4Archive.Builder.Create(ba2, manager),
                _ => throw new NotImplementedException()
            };
        }
    }
}