RT05.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Text;

using Syroot.BinaryData;

namespace PDTools.RText;

/// <summary>
/// Gran Turismo 6 Localization Strings (Encryption)
/// </summary>
public class RT05 : RTextBase
{
    public static readonly string Magic = "RT05";
    public const int HeaderSize = 0x20;


    public RT05(string filePath)
    {
        if (!File.Exists(filePath))
            throw new FileNotFoundException();
    }

    public RT05()
    {

    }

    public void GetCategoryByIndex()
    {
        throw new NotImplementedException();
    }

    public void GetStringByCategory(int categoryIndex)
    {
        throw new NotImplementedException();
    }

    public override void Read(byte[] data)
    {
        using var ms = new MemoryStream(data);
        using var reader = new BinaryStream(ms, ByteConverter.Big);
        reader.BaseStream.Position = 0;
        if (reader.ReadString(4) != Magic)
            throw new Exception($"Invalid magic, doesn't match {Magic}.");

        int entryCount = reader.ReadInt32();

        // Relocation ptr is at 0x10

        // Data starts at 0x20

        for (int i = 0; i < entryCount; i++)
        {
            ms.Position = HeaderSize + (i * 0x10);
            var page = new RT05Page();
            page.Read(reader);
            _pages.Add(page.Name, page);
        }
    }

    public override void Save(string fileName)
    {
        using var ms = new FileStream(fileName, FileMode.Create);
        using var bs = new BinaryStream(ms, ByteConverter.Big);
        bs.Write(Encoding.ASCII.GetBytes(Magic));
        bs.Write(_pages.Count);
        bs.Write((byte)1); // "Obfuscated", we don't know, eboot doesn't read it
        bs.BaseStream.Position = HeaderSize;

        int i = 0;
        int baseDataPos = HeaderSize + (_pages.Count * 0x10);
        foreach (var pagePair in _pages)
        {
            int baseEntryOffset = (int)HeaderSize + (i * 0x10);
            pagePair.Value.Write(bs, baseEntryOffset, baseDataPos);
            baseDataPos = (int)ms.Position;
            i++;
        }
    }
}