protected override void _Read(BinaryReader reader)
{
long baseOffset = reader.BaseStream.Position;
//Read header
Signature = reader.ReadUInt32();
if (!IsValid(Signature))
{
throw new InvalidFileSignatureException();
}
DictionaryOffset = reader.ReadUInt32();
FileCount = reader.ReadUInt32();
ContentSize = reader.ReadUInt32();
Entries.Clear();
//Read the table of content
reader.BaseStream.Seek(baseOffset + DictionaryOffset, SeekOrigin.Begin);
for (int i = 0; i < FileCount; i++)
{
IPACEntry entry = new IPACEntry();
entry.Read(reader);
entry.Index = (uint)i;
Entries.Add(entry);
}
//Read the data to the buffer of the table of content entries
foreach (IPACEntry entry in Entries)
{
reader.BaseStream.Seek(baseOffset + entry.Offset, SeekOrigin.Begin);
entry.Buffer = reader.ReadBytes((int)entry.FileSize);
}
}
/// <summary>
/// Packs the given files into the IPAC object.
/// The input files must have the same format as the unpack method
/// or the file entries have to be added manually.
/// </summary>
public void Pack(List <string> filepaths)
{
Entries.Clear();
foreach (string filepath in filepaths)
{
IPACEntry entry = new IPACEntry();
entry.Extension = Path.GetExtension(filepath).Substring(1, 4).ToUpper();
entry.Filename = Path.GetFileNameWithoutExtension(filepath).ToUpper();
using (FileStream stream = new FileStream(filepath, FileMode.Open))
{
entry.FileSize = (uint)stream.Length;
entry.Buffer = new byte[stream.Length];
stream.Read(entry.Buffer, 0, entry.Buffer.Length);
}
Entries.Add(entry);
}
}
protected override void _Write(BinaryWriter writer)
{
long baseOffset = writer.BaseStream.Length;
FileCount = (uint)Entries.Count;
//Calculate offsets
uint offset = 16;
foreach (IPACEntry entry in Entries)
{
entry.Offset = offset;
offset += entry.FileSize;
offset += 16 - (offset % 16);
offset += 16; //16 byte padding
}
ContentSize = offset;
DictionaryOffset = ContentSize;
//Write header
writer.Write(Signature);
writer.Write(DictionaryOffset);
writer.Write(FileCount);
writer.Write(ContentSize);
//Write the data of the table of content files
foreach (IPACEntry entry in Entries)
{
writer.BaseStream.Seek(baseOffset + entry.Offset, SeekOrigin.Begin);
writer.Write(entry.Buffer);
}
//Write table of contents
writer.BaseStream.Seek(baseOffset + DictionaryOffset, SeekOrigin.Begin);
for (int i = 0; i < Entries.Count; i++)
{
IPACEntry entry = Entries[i];
entry.Index = (uint)i;
entry.Write(writer);
}
}
