wabbajack/Wabbajack.Compression.BSA/FO4Archive/Builder.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Wabbajack.Compression.BSA.Interfaces;
using Wabbajack.DTOs.BSA.ArchiveStates;
using Wabbajack.DTOs.BSA.FileStates;
using Wabbajack.Paths.IO;

namespace Wabbajack.Compression.BSA.FO4Archive
{
    public class Builder : IBuilder
    {
        private List<IFileBuilder> _entries = new();
        private DiskSlabAllocator _slab;
        private BA2State _state;

        public async ValueTask AddFile(AFile state, Stream src, CancellationToken token)
        {
            switch (_state.Type)
            {
                case BA2EntryType.GNRL:
                    var result = await FileEntryBuilder.Create((BA2File)state, src, _slab, token);
                    lock (_entries)
                    {
                        _entries.Add(result);
                    }

                    break;
                case BA2EntryType.DX10:
                    var resultdx10 = await DX10FileEntryBuilder.Create((BA2DX10File)state, src, _slab, token);
                    lock (_entries)
                    {
                        _entries.Add(resultdx10);
                    }

                    break;
            }
        }

        public async ValueTask Build(Stream fs, CancellationToken token)
        {
            SortEntries();
            await using var bw = new BinaryWriter(fs, Encoding.Default, true);

            bw.Write(Encoding.ASCII.GetBytes(_state.HeaderMagic));
            bw.Write(_state.Version);
            bw.Write(Encoding.ASCII.GetBytes(Enum.GetName(_state.Type)!));
            bw.Write((uint)_entries.Count);
            var tableOffsetLoc = bw.BaseStream.Position;
            bw.Write((ulong)0);

            foreach (var entry in _entries) entry.WriteHeader(bw, token);

            foreach (var entry in _entries) await entry.WriteData(bw, token);

            if (!_state.HasNameTable) return;

            var pos = bw.BaseStream.Position;
            bw.BaseStream.Seek(tableOffsetLoc, SeekOrigin.Begin);
            bw.Write((ulong)pos);
            bw.BaseStream.Seek(pos, SeekOrigin.Begin);

            foreach (var entry in _entries)
            {
                var bytes = Encoding.UTF8.GetBytes(entry.FullName);
                bw.Write((ushort)bytes.Length);
                await bw.BaseStream.WriteAsync(bytes, token);
            }
        }

        public static Builder Create(BA2State state, TemporaryFileManager manager)
        {
            var self = new Builder { _state = state, _slab = new DiskSlabAllocator(manager) };
            return self;
        }

        public async ValueTask DisposeAsync()
        {
            await _slab.DisposeAsync();
        }

        private void SortEntries()
        {
            _entries = _entries.OrderBy(e => e.Index).ToList();
        }
    }
}