/***************************************************************************************
Decompress - Sample 3
Copyright (C) 2000-2023 by Matthew T. Ashland   All Rights Reserved.
Feel free to use this code in any way that you like.

This example illustrates dynamic linkage to MACDll.dll to decompress a whole file
and display a simple checksum. (see Sample 1 and Sample 2 for more info)

General Notes:
    -the terminology "Sample" refers to a single sample value, and "Block" refers
    to a collection    of "Channel" samples.  For simplicity, MAC typically uses blocks
    everywhere so that channel mis-alignment cannot happen.

Notes for use in a new project:
    -life will be easier if you set the [MAC SDK]\\Shared directory as an include
    directory and an additional library input path in the project settings
    -set the runtime library to "Mutlithreaded"

WARNING:
    -This class driven system for using Monkey's Audio is still in development, so
    I can't make any guarantees that the classes and libraries won't change before
    everything gets finalized.  Use them at your own risk
***************************************************************************************/

// includes
#include <windows.h>
#include "stdio.h"
#include "All.h"
#include "MACDll.h"
#include "MACLib.h"

/***************************************************************************************
MAC_DLL structure (holds function pointers)
***************************************************************************************/
struct MAC_DLL
{
    // APEDecompress functions
    proc_APEDecompress_Create            Create;
    proc_APEDecompress_Destroy            Destroy;
    proc_APEDecompress_GetData            GetData;
    proc_APEDecompress_Seek                Seek;
    proc_APEDecompress_GetInfo            GetInfo;
};

/***************************************************************************************
GetFunctions - helper that gets the function addresses for the functions we need
***************************************************************************************/
int GetFunctions(HMODULE hMACDll, MAC_DLL * pMACDll)
{
    // clear
    memset(pMACDll, 0, sizeof(MAC_DLL));

    // load the functions
    if (hMACDll != NULL)
    {
        pMACDll->Create = (proc_APEDecompress_Create) GetProcAddress(hMACDll, "c_APEDecompress_Create");
        pMACDll->Destroy = (proc_APEDecompress_Destroy) GetProcAddress(hMACDll, "c_APEDecompress_Destroy");
        pMACDll->GetData = (proc_APEDecompress_GetData) GetProcAddress(hMACDll, "c_APEDecompress_GetData");
        pMACDll->Seek = (proc_APEDecompress_Seek) GetProcAddress(hMACDll, "c_APEDecompress_Seek");
        pMACDll->GetInfo = (proc_APEDecompress_GetInfo) GetProcAddress(hMACDll, "c_APEDecompress_GetInfo");
    }

    // error check
    if ((pMACDll->Create == NULL) ||
        (pMACDll->Destroy == NULL) ||
        (pMACDll->GetData == NULL) ||
        (pMACDll->Seek == NULL) ||
        (pMACDll->GetInfo == NULL))
    {
        return -1;
    }

    return 0;
}

/***************************************************************************************
Version checks the dll / interface
***************************************************************************************/
int VersionCheckInterface(HMODULE hMACDll)
{
    int nRetVal = -1;
    proc_GetInterfaceCompatibility GetInterfaceCompatibility = (proc_GetInterfaceCompatibility) GetProcAddress(hMACDll, "GetInterfaceCompatibility");
    if (GetInterfaceCompatibility)
    {
        nRetVal = GetInterfaceCompatibility(MAC_FILE_VERSION_NUMBER, TRUE, NULL);
    }

    return nRetVal;
}

/***************************************************************************************
Main (the main function)
***************************************************************************************/
int main(int argc, char* argv[])
{
    ///////////////////////////////////////////////////////////////////////////////
    // error check the command line parameters
    ///////////////////////////////////////////////////////////////////////////////
    if (argc != 2)
    {
        printf("~~~Improper Usage~~~\r\n\r\n");
        printf("Usage Example: Sample 3.exe \"c:\\1.ape\"\r\n\r\n");
        return 0;
    }

    ///////////////////////////////////////////////////////////////////////////////
    // variable declares
    ///////////////////////////////////////////////////////////////////////////////
    int nRetVal = 0;            // generic holder for return values
    char * pFilename = argv[1];    // the file to open

    ///////////////////////////////////////////////////////////////////////////////
    // load MACDll.dll and get the functions
    ///////////////////////////////////////////////////////////////////////////////

    // load the DLL
#if _WIN64
    HMODULE hMACDll = LoadLibrary(_T("C:\\Windows\\System32\\MACDll64.dll"));
#else
    HMODULE hMACDll = LoadLibrary(_T("C:\\Windows\\SysWOW64\\MACDll.dll"));
#endif
    if (hMACDll == NULL)
        return -1;

    // always check the interface version (so we don't crash if something changed)
    if (VersionCheckInterface(hMACDll) != 0)
    {
        FreeLibrary(hMACDll);
        return -1;
    }

    // get the functions
    MAC_DLL MACDll;
    if (GetFunctions(hMACDll, &MACDll) != 0)
    {
        FreeLibrary(hMACDll);
        return -1;
    }

    ///////////////////////////////////////////////////////////////////////////////
    // create the APEDecompress object for the file
    ///////////////////////////////////////////////////////////////////////////////

    APE_DECOMPRESS_HANDLE hAPEDecompress = MACDll.Create(pFilename, &nRetVal);
    if (hAPEDecompress == NULL)
    {
        printf("Error opening APE file (error code: %d)\r\n", nRetVal);
        FreeLibrary(hMACDll);
        return -1;
    }

    ///////////////////////////////////////////////////////////////////////////////
    // calculate a byte-level checksum of the whole file
    ///////////////////////////////////////////////////////////////////////////////

    // make a buffer to hold 1024 blocks of audio data
    APE::int64 nBlockAlign = MACDll.GetInfo(hAPEDecompress, APE::IAPEDecompress::APE_INFO_BLOCK_ALIGN, 0, 0);
    unsigned char * pBuffer = new unsigned char [size_t(1024 * nBlockAlign)];

    // loop through the whole file
    APE::int64 nTotalBlocks = MACDll.GetInfo(hAPEDecompress, APE::IAPEDecompress::APE_DECOMPRESS_TOTAL_BLOCKS, 0, 0);
    APE::int64 nBlocksRetrieved = 1;
    APE::int64 nTotalBlocksRetrieved = 0;
    unsigned int nChecksum = 0;
    while (nBlocksRetrieved > 0)
    {
        // try to decompress 1024 blocks
        nRetVal = MACDll.GetData(hAPEDecompress, (char *) pBuffer, 1024, &nBlocksRetrieved);
        if (nRetVal != 0)
            printf("Decompression error (continuing with checksum, but file is probably corrupt)\r\n");

        // calculate the sum (byte-by-byte)
        for (int z = 0; z < (nBlockAlign * nBlocksRetrieved); z++)
        {
            nChecksum += abs(int(pBuffer[z]));
        }

        nTotalBlocksRetrieved += nBlocksRetrieved;

        // output the progress
        printf("Progress: %.1f%%          \r", (float(nTotalBlocksRetrieved) * float(100)) / float(max(nTotalBlocks, 1.0)));
    }

    delete [] pBuffer;

    // output the result
    printf("Progress: done.                          \r\n");
    printf("Stupid-style Checksum: 0x%X\r\n", nChecksum);

    ///////////////////////////////////////////////////////////////////////////////
    // clean-up and quit
    ///////////////////////////////////////////////////////////////////////////////
    MACDll.Destroy(hAPEDecompress);
    FreeLibrary(hMACDll);
    return 0;
}
