/*
 * PROJECT:     ReactOS Applications Manager
 * LICENSE:     GPL-2.0-or-later (https://spdx.org/licenses/GPL-2.0-or-later)
 * PURPOSE:     Cabinet extraction using FDI API
 * COPYRIGHT:   Copyright 2018 Alexander Shaposhnikov (sanchaez@reactos.org)
 */
#include "rapps.h"
#include <debug.h>

#include <fdi.h>
#include <fcntl.h>

/*
 * HACK: treat any input strings as Unicode (UTF-8)
 * cabinet.dll lacks any sort of a Unicode API, but FCI/FDI
 * provide an ability to use user-defined callbacks for any file or memory
 * operations. This flexibility and the magic power of C/C++ casting allows
 * us to treat input as we please.
 * This is by far the best way to extract .cab using Unicode paths.
 */

/* String conversion helper functions */

// converts CStringW to CStringA using a given codepage
inline BOOL
WideToMultiByte(const CStringW &szSource, CStringA &szDest, UINT Codepage)
{
    // determine the needed size
    INT sz = WideCharToMultiByte(Codepage, 0, szSource, -1, NULL, NULL, NULL, NULL);
    if (!sz)
        return FALSE;

    // do the actual conversion
    sz = WideCharToMultiByte(Codepage, 0, szSource, -1, szDest.GetBuffer(sz), sz, NULL, NULL);

    szDest.ReleaseBuffer();
    return sz != 0;
}

// converts CStringA to CStringW using a given codepage
inline BOOL
MultiByteToWide(const CStringA &szSource, CStringW &szDest, UINT Codepage)
{
    // determine the needed size
    INT sz = MultiByteToWideChar(Codepage, 0, szSource, -1, NULL, NULL);
    if (!sz)
        return FALSE;

    // do the actual conversion
    sz = MultiByteToWideChar(CP_UTF8, 0, szSource, -1, szDest.GetBuffer(sz), sz);

    szDest.ReleaseBuffer();
    return sz != 0;
}

/* FDICreate callbacks */

FNALLOC(fnMemAlloc)
{
    return HeapAlloc(GetProcessHeap(), NULL, cb);
}

FNFREE(fnMemFree)
{
    HeapFree(GetProcessHeap(), NULL, pv);
}

FNOPEN(fnFileOpen)
{
    HANDLE hFile = NULL;
    DWORD dwDesiredAccess = 0;
    DWORD dwCreationDisposition = 0;
    CStringW szFileName;

    UNREFERENCED_PARAMETER(pmode);

    if (oflag & _O_RDWR)
    {
        dwDesiredAccess = GENERIC_READ | GENERIC_WRITE;
    }
    else if (oflag & _O_WRONLY)
    {
        dwDesiredAccess = GENERIC_WRITE;
    }
    else
    {
        dwDesiredAccess = GENERIC_READ;
    }

    if (oflag & _O_CREAT)
    {
        dwCreationDisposition = CREATE_ALWAYS;
    }
    else
    {
        dwCreationDisposition = OPEN_EXISTING;
    }

    MultiByteToWide(pszFile, szFileName, CP_UTF8);

    hFile = CreateFileW(
        szFileName, dwDesiredAccess, FILE_SHARE_READ, NULL, dwCreationDisposition, FILE_ATTRIBUTE_NORMAL, NULL);

    return (INT_PTR)hFile;
}

FNREAD(fnFileRead)
{
    DWORD dwBytesRead = 0;

    if (ReadFile((HANDLE)hf, pv, cb, &dwBytesRead, NULL) == FALSE)
    {
        dwBytesRead = (DWORD)-1L;
    }

    return dwBytesRead;
}

FNWRITE(fnFileWrite)
{
    DWORD dwBytesWritten = 0;

    if (WriteFile((HANDLE)hf, pv, cb, &dwBytesWritten, NULL) == FALSE)
    {
        dwBytesWritten = (DWORD)-1;
    }

    return dwBytesWritten;
}

FNCLOSE(fnFileClose)
{
    return (CloseHandle((HANDLE)hf) != FALSE) ? 0 : -1;
}

FNSEEK(fnFileSeek)
{
    return SetFilePointer((HANDLE)hf, dist, NULL, seektype);
}

/* FDICopy callbacks */

FNFDINOTIFY(fnNotify)
{
    INT_PTR iResult = 0;

    switch (fdint)
    {
        case fdintCOPY_FILE:
        {
            CStringW szExtractDir, szCabFileName;

            // Append the destination directory to the file name.
            MultiByteToWide((LPCSTR)pfdin->pv, szExtractDir, CP_UTF8);
            MultiByteToWide(pfdin->psz1, szCabFileName, CP_ACP);

            if (szCabFileName.Find('\\') >= 0)
            {
                CStringW szNewDirName = szExtractDir;
                int nTokenPos = 0;
                // We do not want to interpret the filename as directory,
                // so bail out before the last token!
                while (szCabFileName.Find('\\', nTokenPos) >= 0)
                {
                    CStringW token = szCabFileName.Tokenize(L"\\", nTokenPos);
                    if (token.IsEmpty())
                        break;

                    szNewDirName += L"\\" + token;
                    if (!CreateDirectoryW(szNewDirName, NULL))
                    {
                        DWORD dwErr = GetLastError();
                        if (dwErr != ERROR_ALREADY_EXISTS)
                        {
                            DPRINT1(
                                "ERROR: Unable to create directory %S (err %lu)\n", szNewDirName.GetString(), dwErr);
                        }
                    }
                }
            }

            CStringW szNewFileName = szExtractDir + L"\\" + szCabFileName;

            CStringA szFilePathUTF8;
            WideToMultiByte(szNewFileName, szFilePathUTF8, CP_UTF8);

            // Open the file
            iResult = fnFileOpen((LPSTR)szFilePathUTF8.GetString(), _O_WRONLY | _O_CREAT, 0);
        }
        break;

        case fdintCLOSE_FILE_INFO:
            iResult = !fnFileClose(pfdin->hf);
            break;

        case fdintNEXT_CABINET:
            if (pfdin->fdie != FDIERROR_NONE)
            {
                iResult = -1;
            }
            break;

        case fdintPARTIAL_FILE:
            iResult = 0;
            break;

        case fdintCABINET_INFO:
            iResult = 0;
            break;

        case fdintENUMERATE:
            iResult = 0;
            break;

        default:
            iResult = -1;
            break;
    }

    return iResult;
}

/* cabinet.dll FDI function pointers */

typedef HFDI (*fnFDICreate)(PFNALLOC, PFNFREE, PFNOPEN, PFNREAD, PFNWRITE, PFNCLOSE, PFNSEEK, int, PERF);

typedef BOOL (*fnFDICopy)(HFDI, LPSTR, LPSTR, INT, PFNFDINOTIFY, PFNFDIDECRYPT, void FAR *pvUser);

typedef BOOL (*fnFDIDestroy)(HFDI);

/*
 * Extraction function
 * TODO: require only a full path to the cab as an argument
 */
BOOL
ExtractFilesFromCab(const CStringW &szCabName, const CStringW &szCabDir, const CStringW &szOutputDir)
{
    HINSTANCE hCabinetDll;
    HFDI ExtractHandler;
    ERF ExtractErrors;
    ATL::CStringA szCabNameUTF8, szCabDirUTF8, szOutputDirUTF8;
    fnFDICreate pfnFDICreate;
    fnFDICopy pfnFDICopy;
    fnFDIDestroy pfnFDIDestroy;
    BOOL bResult;

    // Load cabinet.dll and extract needed functions
    hCabinetDll = LoadLibraryW(L"cabinet.dll");

    if (!hCabinetDll)
    {
        return FALSE;
    }

    pfnFDICreate = (fnFDICreate)GetProcAddress(hCabinetDll, "FDICreate");
    pfnFDICopy = (fnFDICopy)GetProcAddress(hCabinetDll, "FDICopy");
    pfnFDIDestroy = (fnFDIDestroy)GetProcAddress(hCabinetDll, "FDIDestroy");

    if (!pfnFDICreate || !pfnFDICopy || !pfnFDIDestroy)
    {
        FreeLibrary(hCabinetDll);
        return FALSE;
    }

    // Create FDI context
    ExtractHandler = pfnFDICreate(
        fnMemAlloc, fnMemFree, fnFileOpen, fnFileRead, fnFileWrite, fnFileClose, fnFileSeek, cpuUNKNOWN,
        &ExtractErrors);

    if (!ExtractHandler)
    {
        FreeLibrary(hCabinetDll);
        return FALSE;
    }

    // Create output dir
    bResult = CreateDirectoryW(szOutputDir, NULL);

    if (bResult || GetLastError() == ERROR_ALREADY_EXISTS)
    {
        // Convert wide strings to UTF-8
        bResult = WideToMultiByte(szCabName, szCabNameUTF8, CP_UTF8);
        bResult &= WideToMultiByte(szCabDir, szCabDirUTF8, CP_UTF8);
        bResult &= WideToMultiByte(szOutputDir, szOutputDirUTF8, CP_UTF8);
    }

    // Perform extraction
    if (bResult)
    {
        // Add a slash to cab name as required by the api
        szCabNameUTF8 = "\\" + szCabNameUTF8;

        bResult = pfnFDICopy(
            ExtractHandler, (LPSTR)szCabNameUTF8.GetString(), (LPSTR)szCabDirUTF8.GetString(), 0, fnNotify, NULL,
            (void FAR *)szOutputDirUTF8.GetString());
    }

    pfnFDIDestroy(ExtractHandler);
    FreeLibrary(hCabinetDll);
    return bResult;
}