199 lines
7.4 KiB
C#

//! \file ArcAi5Win.cs
//! \date Mon Jun 29 04:41:29 2015
//! \brief Ai5Win engine resource archive.
//
// Copyright (C) 2015-2018 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.Collections.Generic;
using System.ComponentModel.Composition;
using System.IO;
using System.Linq;
using GameRes.Compression;
using GameRes.Utility;
namespace GameRes.Formats.Elf
{
[Serializable]
public class ArcIndexScheme
{
public int NameLength;
public byte NameKey;
public uint SizeKey;
public uint OffsetKey;
}
[Serializable]
public class Ai5Scheme : ResourceScheme
{
public Dictionary<string, ArcIndexScheme> KnownSchemes;
}
[Export(typeof(ArchiveFormat))]
[ExportMetadata("Priority", -1)]
public class ArcAI5Opener : ArchiveFormat
{
public override string Tag { get { return "ARC/AI5WIN"; } }
public override string Description { get { return "AI5WIN engine resource archive"; } }
public override uint Signature { get { return 0; } }
public override bool IsHierarchic { get { return false; } }
public override bool CanWrite { get { return false; } }
static Ai5Scheme DefaultScheme = new Ai5Scheme { KnownSchemes = new Dictionary<string, ArcIndexScheme>() };
public Dictionary<string, ArcIndexScheme> KnownSchemes { get { return DefaultScheme.KnownSchemes; } }
public override ResourceScheme Scheme
{
get { return DefaultScheme; }
set { DefaultScheme = (Ai5Scheme)value; }
}
public override ArcFile TryOpen (ArcView file)
{
if (0 == KnownSchemes.Count)
return null;
int count = file.View.ReadInt32 (0);
if (!IsSaneCount (count))
return null;
var reader = new Ai5ArcIndexReader (file, count);
var dir = reader.TrySchemes (KnownSchemes.Values);
if (null == dir)
dir = reader.TrySchemes (reader.GuessSchemes());
if (null == dir)
return null;
return new ArcFile (file, this, dir);
}
public override Stream OpenEntry (ArcFile arc, Entry entry)
{
var input = arc.File.CreateStream (entry.Offset, entry.Size);
if (entry.Name.HasAnyOfExtensions ("mes", "lib", "a", "a6", "msk", "x"))
return new LzssStream (input);
return input;
}
}
internal class Ai5ArcIndexReader
{
protected ArcView m_file;
protected int m_count;
protected List<Entry> m_dir;
protected byte[] m_name_buf = new byte[0x100];
public Ai5ArcIndexReader (ArcView file, int count)
{
m_file = file;
m_count = count;
m_dir = new List<Entry> (m_count);
}
public List<Entry> TrySchemes (IEnumerable<ArcIndexScheme> schemes)
{
foreach (var scheme in schemes)
{
try
{
var dir = Read (scheme);
if (dir != null)
return dir;
}
catch { /* ignore parse errors */ }
}
return null;
}
public List<Entry> Read (ArcIndexScheme scheme)
{
if (scheme.NameLength > m_name_buf.Length)
m_name_buf = new byte[scheme.NameLength];
m_dir.Clear();
int index_offset = 4;
uint index_size = (uint)(m_count * (scheme.NameLength + 8));
if (index_size > m_file.View.Reserve (index_offset, index_size))
return null;
for (int i = 0; i < m_count; ++i)
{
m_file.View.Read (index_offset, m_name_buf, 0, (uint)scheme.NameLength);
string name = DecryptName (scheme);
if (string.IsNullOrWhiteSpace (name))
return null;
index_offset += scheme.NameLength;
var entry = FormatCatalog.Instance.Create<Entry> (name);
entry.Size = m_file.View.ReadUInt32 (index_offset) ^ scheme.SizeKey;
entry.Offset = m_file.View.ReadUInt32 (index_offset+4) ^ scheme.OffsetKey;
if (entry.Offset < index_size+4 || !entry.CheckPlacement (m_file.MaxOffset))
return null;
m_dir.Add (entry);
index_offset += 8;
}
return m_dir;
}
internal string DecryptName (ArcIndexScheme scheme)
{
int n;
for (n = 0; n < m_name_buf.Length; ++n)
{
if (n > scheme.NameLength)
return null;
m_name_buf[n] ^= scheme.NameKey;
if (0 == m_name_buf[n])
break;
if (m_name_buf[n] < 0x20)
return null;
}
if (n != 0)
return Encodings.cp932.GetString (m_name_buf, 0, n);
else
return null;
}
internal IEnumerable<ArcIndexScheme> GuessSchemes ()
{
if (m_count < 2)
yield break;
foreach (int name_length in NameLengths)
{
uint data_offset = (uint)((name_length + 8) * m_count + 4);
byte name_key = m_file.View.ReadByte (3 + name_length);
uint first_size = m_file.View.ReadUInt32 (4 + name_length);
uint first_offset = m_file.View.ReadUInt32 (8 + name_length);
uint offset_key = data_offset ^ first_offset;
uint second_offset = m_file.View.ReadUInt32 ((name_length+8) * 2) ^ offset_key;
if (second_offset < data_offset || second_offset >= m_file.MaxOffset)
continue;
uint size_key = (second_offset - data_offset) ^ first_size;
if (0 == offset_key || 0 == size_key)
continue;
yield return new ArcIndexScheme {
NameLength = name_length,
NameKey = name_key,
SizeKey = size_key,
OffsetKey = offset_key,
};
}
}
static readonly int[] NameLengths = { 0x14, 0x1E, 0x20, 0x100 };
}
}