/*---------------------------------------------------------------------------*
  Project:  Horizon
  File:     main.cpp

  Copyright (C)2009-2012 Nintendo Co., Ltd.  All rights reserved.

  These coded instructions, statements, and computer programs contain
  proprietary information of Nintendo of America Inc. and/or Nintendo
  Company Ltd., and are protected by Federal copyright law.  They may
  not be disclosed to third parties or copied or duplicated in any form,
  in whole or in part, without the prior written consent of Nintendo.

  $Rev: 46365 $
 *---------------------------------------------------------------------------*/

#include <nn.h>
#include <nn/cx.h>
#include <nn/applet.h>

void nnMain()
{
    // With this flag, the API used for expansion is switched
    //   false : UncompressBLZ() ......... Although the error check is insufficient, it is faster than the Secure version
    //   true : SecureUncompressBLZ() ... Error check is performed, but is slower than the non-Secure version
    const bool uncompressWithErrorCheck = false;

    NN_LOG("UncompressBlz demo\n");

    // Call only nn::applet::Enable to also allow execution from the HOME Menu
    // HOME Menu transitions, POWER Button presses, and sleep are all unsupported
    nn::applet::Enable();

    // Initialize fs, mount ROM
    nn::fs::Initialize();
    const size_t ROMFS_BUFFER_SIZE = 1024 * 64;
    static char buffer[ROMFS_BUFFER_SIZE];
    NN_UTIL_PANIC_IF_FAILED(nn::fs::MountRom(16, 16, buffer, ROMFS_BUFFER_SIZE));

    // Load compressed file, and get the data size after expansion
    u8 archive[4096];
    nn::fs::FileReader reader;
    reader.Initialize("rom:/archive.bin");
    u32 inSize = reader.GetSize();
    reader.Read(archive, inSize);
    // The data size after decompression is "size of compressed file" + "value written to the last 4 bytes of the compressed file"
    // 
    u32 outSize;
    reader.Seek(-4, nn::fs::POSITION_BASE_END);
    reader.Read(&outSize, 4);
    outSize += inSize;
    reader.Finalize();
    // Confirm if the buffer length is insufficient
    if (outSize > sizeof(archive))
    {
        NN_PANIC("ERROR: buffer is not large enough\n");
    }

    // BLZ decompression
    // The expanded data is overwritten to the input buffer
    if (uncompressWithErrorCheck)
    {
        s32 ret = nn::cx::SecureUncompressBLZ(archive, inSize, sizeof(archive));
        // Confirm if an error occur during expansion
        if (ret != 0)
        {
            NN_PANIC("ERROR: decode error has occurred\n");
        }
    }
    else
    {
        nn::cx::UncompressBLZ(archive, inSize, sizeof(archive));
    }

    // Comparison to original data
    u8 data[4096];
    reader.Initialize("rom:/data.bin");
    // Confirm if this matches the expansion size obtained from the compressed file
    if (outSize != reader.GetSize())
    {
        NN_PANIC("ERROR: original data size != uncompressed data size\n");
    }
    reader.Read(data, outSize);
    reader.Finalize();
    for (int i = 0; i < outSize; i++)
    {
        if (archive[i] != data[i])
        {
            NN_PANIC("ERROR: original data != uncompressed data\n");
        }
    }

    NN_LOG("UncompressBlz demo finished\n");
}

/*---------------------------------------------------------------------------*
  End of file
 *---------------------------------------------------------------------------*/