253 lines
8.4 KiB
C#

//! \file ArcLINK.cs
//! \date Fri Jan 22 18:44:56 2016
//! \brief KaGuYa archive format.
//
// Copyright (C) 2016 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;
namespace GameRes.Formats.Kaguya
{
[Export(typeof(ArchiveFormat))]
public class PakOpener : ArchiveFormat
{
public override string Tag { get { return "LINK/KAGUYA"; } }
public override string Description { get { return "KaGuYa script engine resource archive"; } }
public override uint Signature { get { return 0x4B4E494C; } } // 'LINK'
public override bool IsHierarchic { get { return false; } }
public override bool CanCreate { get { return false; } }
public override ArcFile TryOpen (ArcView file)
{
int version = file.View.ReadByte (4) - '0';
if (version != 3)
return null;
long current_offset = 8;
var dir = new List<Entry>();
while (current_offset+4 < file.MaxOffset)
{
uint size = file.View.ReadUInt32 (current_offset);
if (0 == size)
break;
if (size < 0x10)
return null;
bool is_compressed = file.View.ReadInt32 (current_offset+4) != 0;
uint name_length = file.View.ReadByte (current_offset+0xD);
var name = file.View.ReadString (current_offset+0x10, name_length);
current_offset += 0x10 + name_length;
var entry = FormatCatalog.Instance.Create<PackedEntry> (name);
entry.Offset = current_offset;
entry.Size = size - (0x10 + name_length);
entry.IsPacked = is_compressed;
dir.Add (entry);
current_offset += entry.Size;
}
return new ArcFile (file, this, dir);
}
public override Stream OpenEntry (ArcFile arc, Entry entry)
{
var pent = entry as PackedEntry;
if (null == pent || !pent.IsPacked || !arc.File.View.AsciiEqual (entry.Offset, "BMR"))
return base.OpenEntry (arc, entry);
using (var input = arc.File.CreateStream (entry.Offset, entry.Size))
using (var bmr = new BmrDecoder (input))
{
bmr.Unpack();
return new MemoryStream (bmr.Data);
}
}
}
internal class BmrDecoder : IDisposable
{
byte[] m_output;
MsbBitStream m_input;
int m_final_size;
int m_step;
int m_key;
public byte[] Data { get { return m_output; } }
public BmrDecoder (Stream input)
{
input.Position = 3;
using (var header = new ArcView.Reader (input))
{
m_step = header.ReadByte();
m_final_size = header.ReadInt32();
m_key = header.ReadInt32();
int unpacked_size = header.ReadInt32();
m_output = new byte[unpacked_size];
m_input = new MsbBitStream (input, true);
}
}
public void Unpack ()
{
m_input.Input.Position = 0x14;
UnpackHuffman();
DescrambleOutput();
m_output = Decode (m_output, m_key);
if (m_step != 0)
m_output = DecompressRLE();
}
byte[] DecompressRLE ()
{
var result = new byte[m_final_size];
int src = 0;
for (int i = 0; i < m_step; ++i)
{
byte v1 = m_output[src++];
result[i] = v1;
int dst = i + m_step;
while (dst < result.Length)
{
byte v2 = m_output[src++];
result[dst] = v2;
dst += m_step;
if (v2 == v1)
{
int count = m_output[src++];
if (0 != (count & 0x80))
count = m_output[src++] + ((count & 0x7F) << 8) + 128;
while (count --> 0)
{
result[dst] = v2;
dst += m_step;
}
if (dst < m_output.Length)
{
v2 = m_output[src++];
result[dst] = v2;
dst += m_step;
}
}
v1 = v2;
}
}
return result;
}
void DescrambleOutput ()
{
var scramble = new byte[256];
for (int i = 0; i < 256; ++i)
scramble[i] = (byte)i;
for (int i = 0; i < m_output.Length; ++i)
{
byte v = m_output[i];
m_output[i] = scramble[v];
for (int j = v; j > 0; --j)
{
scramble[j] = scramble[j-1];
}
scramble[0] = m_output[i];
}
}
byte[] Decode (byte[] input, int key)
{
var freq_table = new int[256];
for (int i = 0; i < input.Length; ++i)
{
++freq_table[input[i]];
}
for (int i = 1; i < 256; ++i)
{
freq_table[i] += freq_table[i-1];
}
var distrib_table = new int[input.Length];
for (int i = input.Length-1; i >= 0; --i)
{
int v = input[i];
int freq = freq_table[v] - 1;
freq_table[v] = freq;
distrib_table[freq] = i;
}
int pos = key;
var copy_out = new byte[input.Length];
for (int i = 0; i < copy_out.Length; ++i)
{
pos = distrib_table[pos];
copy_out[i] = input[pos];
}
return copy_out;
}
ushort m_token;
ushort[,] m_tree = new ushort[2,256];
void UnpackHuffman ()
{
m_token = 256;
ushort root = CreateHuffmanTree();
int dst = 0;
while (dst < m_output.Length)
{
ushort symbol = root;
while (symbol >= 0x100)
{
int bit = m_input.GetNextBit();
if (-1 == bit)
throw new EndOfStreamException();
symbol = m_tree[bit,symbol-256];
}
m_output[dst++] = (byte)symbol;
}
}
ushort CreateHuffmanTree ()
{
if (0 != m_input.GetNextBit())
{
ushort v = m_token++;
m_tree[0,v-256] = CreateHuffmanTree();
m_tree[1,v-256] = CreateHuffmanTree();
return v;
}
else
{
return (ushort)m_input.GetBits (8);
}
}
#region IDisposable Members
bool _disposed = false;
public void Dispose ()
{
if (!_disposed)
{
m_input.Dispose();
_disposed = true;
}
}
#endregion
}
}