moved ArcNexas to separate directory.

ArcFormats/Nexas/ArcPAC.cs

@@ -0,0 +1,150 @@
+//! \file       ArcNexas.cs
+//! \date       Sat Mar 14 18:03:04 2015
+//! \brief      NeXAS enginge resource archives implementation.
+//
+// Copyright (C) 2015 by morkt
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+//
+
+using System;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Collections.Generic;
+using System.ComponentModel.Composition;
+using GameRes.Compression;
+using GameRes.Formats.Strings;
+using GameRes.Utility;
+
+namespace GameRes.Formats.NeXAS
+{
+    public enum Compression
+    {
+        None,
+        Lzss,
+        Huffman,
+        Deflate,
+        DeflateOrNone,
+    }
+
+    public class PacArchive : ArcFile
+    {
+        public readonly Compression PackType;
+
+        public PacArchive (ArcView arc, ArchiveFormat impl, ICollection<Entry> dir, Compression type)
+            : base (arc, impl, dir)
+        {
+            PackType = type;
+        }
+    }
+
+    [Export(typeof(ArchiveFormat))]
+    public class PacOpener : ArchiveFormat
+    {
+        public override string         Tag { get { return "PAC"; } }
+        public override string Description { get { return "NeXAS engine resource archive"; } }
+        public override uint     Signature { get { return 0x00434150; } } // 'PAC\000'
+        public override bool  IsHierarchic { get { return false; } }
+        public override bool     CanCreate { get { return false; } }
+
+        public PacOpener ()
+        {
+            Signatures = new uint[] { 0x00434150, 0 };
+        }
+
+        public override ArcFile TryOpen (ArcView file)
+        {
+            if (!file.View.AsciiEqual (0, "PAC") || 'K' == file.View.ReadByte (3))
+                return null;
+            int count = file.View.ReadInt32 (4);
+            if (!IsSaneCount (count))
+                return null;
+            int pack_type = file.View.ReadInt32 (8);
+            uint index_size = file.View.ReadUInt32 (file.MaxOffset-4);
+            if (index_size >= file.MaxOffset)
+                return null;
+
+            byte[] index_packed = new byte[index_size];
+            file.View.Read (file.MaxOffset-4-index_size, index_packed, 0, index_size);
+            for (int i = 0; i < index_packed.Length; ++i)
+                index_packed[i] = (byte)~index_packed[i];
+
+            var index = HuffmanDecode (index_packed, count*0x4c);
+            var dir = new List<Entry> (count);
+            int offset = 0;
+            for (int i = 0; i < count; ++i, offset += 0x4c)
+            {
+                var name = Binary.GetCString (index, offset, 0x40);
+                var entry = new PackedEntry
+                {
+                    Name = name,
+                    Type = FormatCatalog.Instance.GetTypeFromName (name),
+                    Offset = LittleEndian.ToUInt32 (index, offset+0x40),
+                    UnpackedSize = LittleEndian.ToUInt32 (index, offset+0x44),
+                    Size = LittleEndian.ToUInt32 (index, offset+0x48),
+                };
+                if (!entry.CheckPlacement (file.MaxOffset))
+                    return null;
+                entry.IsPacked = pack_type != 0 && (pack_type != 4 || entry.Size != entry.UnpackedSize);
+                dir.Add (entry);
+            }
+            if (0 == pack_type)
+                return new ArcFile (file, this, dir);
+            return new PacArchive (file, this, dir, (Compression)pack_type);
+        }
+
+        public override Stream OpenEntry (ArcFile arc, Entry entry)
+        {
+            var input = arc.File.CreateStream (entry.Offset, entry.Size);
+            var pac = arc as PacArchive;
+            var pent = entry as PackedEntry;
+            if (null == pac || null == pent || !pent.IsPacked)
+                return input;
+            switch (pac.PackType)
+            {
+            case Compression.Lzss:
+                using (input)
+                using (var reader = new LzssReader (input, (int)pent.Size, (int)pent.UnpackedSize))
+                {
+                    reader.Unpack();
+                    return new MemoryStream (reader.Data, false);
+                }
+            case Compression.Huffman:
+                using (input)
+                {
+                    var packed = new byte[entry.Size];
+                    input.Read (packed, 0, packed.Length);
+                    var unpacked = HuffmanDecode (packed, (int)pent.UnpackedSize);
+                    return new MemoryStream (unpacked, 0, (int)pent.UnpackedSize, false);
+                }
+            case Compression.Deflate:
+            default:
+                return new ZLibStream (input, CompressionMode.Decompress);
+            }
+        }
+
+        static private byte[] HuffmanDecode (byte[] packed, int unpacked_size)
+        {
+            var dst = new byte[unpacked_size];
+            var decoder = new HuffmanDecoder (packed, dst);
+            return decoder.Unpack();
+        }
+    }
+}