/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */
 
#include <filter/msfilter/rtfutil.hxx>
#include <rtl/strbuf.hxx>
#include <sal/log.hxx>
#include <osl/diagnose.h>
#include <svtools/rtfkeywd.hxx>
#include <rtl/character.hxx>
#include <tools/stream.hxx>
#include <sot/storage.hxx>
 
namespace
{
/**
 * If rOle1 is native OLE1 data of size nOle1Size, wraps it in an OLE2 container.
 *
 * The OLE2 root's CLSID is set based on rClassName.
 */
void WrapOle1InOle2(SvStream& rOle1, sal_uInt32 nOle1Size, SvStream& rOle2,
                    const OString& rClassName)
{
    rtl::Reference<SotStorage> pStorage = new SotStorage(rOle2);
    OString aAnsiUserType;
    SvGlobalName aName;
    if (rClassName == "PBrush")
    {
        aAnsiUserType = "Bitmap Image"_ostr;
        aName = SvGlobalName(0x0003000A, 0, 0, 0xc0, 0, 0, 0, 0, 0, 0, 0x46);
    }
    else
    {
        if (!rClassName.isEmpty() && rClassName != "Package")
        {
            SAL_WARN("filter.ms", "WrapOle1InOle2: unexpected class name: '" << rClassName << "'");
        }
        aAnsiUserType = "OLE Package"_ostr;
        aName = SvGlobalName(0x0003000C, 0, 0, 0xc0, 0, 0, 0, 0, 0, 0, 0x46);
    }
    pStorage->SetClass(aName, SotClipboardFormatId::NONE, u""_ustr);
 
    // [MS-OLEDS] 2.3.7 CompObjHeader
    rtl::Reference<SotStorageStream> pCompObj = pStorage->OpenSotStream(u"\1CompObj"_ustr);
    // Reserved1
    pCompObj->WriteUInt32(0xfffe0001);
    // Version
    pCompObj->WriteUInt32(0x00000a03);
    // Reserved2
    pCompObj->WriteUInt32(0xffffffff);
    pCompObj->WriteUInt32(0x0003000c);
    pCompObj->WriteUInt32(0x00000000);
    pCompObj->WriteUInt32(0x000000c0);
    pCompObj->WriteUInt32(0x46000000);
    // Rest of CompObjStream
    // AnsiUserType
    pCompObj->WriteUInt32(aAnsiUserType.getLength() + 1);
    pCompObj->WriteOString(aAnsiUserType);
    pCompObj->WriteChar(0);
    // AnsiClipboardFormat
    pCompObj->WriteUInt32(0x00000000);
    // Reserved1
    pCompObj->WriteUInt32(rClassName.getLength() + 1);
    pCompObj->WriteOString(rClassName);
    pCompObj->WriteChar(0);
    // UnicodeMarker
    pCompObj->WriteUInt32(0x71B239F4);
    // UnicodeUserType
    pCompObj->WriteUInt32(0x00000000);
    // UnicodeClipboardFormat
    pCompObj->WriteUInt32(0x00000000);
    // Reserved2
    pCompObj->WriteUInt32(0x00000000);
    pCompObj->Commit();
    pCompObj.clear();
 
    // [MS-OLEDS] 2.3.6 OLENativeStream
    rtl::Reference<SotStorageStream> pOleNative = pStorage->OpenSotStream(u"\1Ole10Native"_ustr);
    // NativeDataSize
    pOleNative->WriteUInt32(nOle1Size);
    pOleNative->WriteStream(rOle1, nOle1Size);
    pOleNative->Commit();
    pOleNative.clear();
 
    pStorage->Commit();
    pStorage.clear();
    rOle2.Seek(0);
}
}
 
namespace msfilter::rtfutil
{
OString OutHex(sal_uLong nHex, sal_uInt8 nLen)
{
    char aNToABuf[] = "0000000000000000";
 
    OSL_ENSURE(nLen < sizeof(aNToABuf), "nLen is too big");
    if (nLen >= sizeof(aNToABuf))
        nLen = (sizeof(aNToABuf) - 1);
 
    // Set pointer to the buffer end
    char* pStr = aNToABuf + (sizeof(aNToABuf) - 1);
    for (sal_uInt8 n = 0; n < nLen; ++n)
    {
        *(--pStr) = static_cast<char>(nHex & 0xf) + 48;
        if (*pStr > '9')
            *pStr += 39;
        nHex >>= 4;
    }
    return pStr;
}
 
// Ideally, this function should work on (sal_uInt32) Unicode scalar values
// instead of (sal_Unicode) UTF-16 code units.  However, at least "Rich Text
// Format (RTF) Specification Version 1.9.1" available at
// <https://www.microsoft.com/en-us/download/details.aspx?id=10725> does not
// look like it allows non-BMP Unicode characters >= 0x10000 in the \uN notation
// (it only talks about "Unicode character", but then explains how values of N
// greater than 32767 will be expressed as negative signed 16-bit numbers, so
// that smells like \uN is limited to BMP).
// However the "Mathematics" section has an example that shows the code point
// U+1D44E being encoded as UTF-16 surrogate pair "\u-10187?\u-9138?", so
// sal_Unicode actually works fine here.
OString OutChar(sal_Unicode c, int* pUCMode, rtl_TextEncoding eDestEnc, bool* pSuccess,
                bool bUnicode)
{
    if (pSuccess)
        *pSuccess = true;
    OStringBuffer aBuf;
    const char* pStr = nullptr;
    // 0x0b instead of \n, etc because of the replacements in SwWW8AttrIter::GetSnippet()
    switch (c)
    {
        case 0x0b:
            // hard line break
            pStr = OOO_STRING_SVTOOLS_RTF_LINE;
            break;
        case '\t':
            pStr = OOO_STRING_SVTOOLS_RTF_TAB;
            break;
        case '\\':
        case '}':
        case '{':
            aBuf.append('\\');
            aBuf.append(static_cast<char>(c));
            break;
        case 0xa0:
            // non-breaking space
            pStr = "\\~";
            break;
        case 0x1e:
            // non-breaking hyphen
            pStr = "\\_";
            break;
        case 0x1f:
            // optional hyphen
            pStr = "\\-";
            break;
        default:
            if (c >= ' ' && c <= '~')
                aBuf.append(static_cast<char>(c));
            else
            {
                OUString sBuf(&c, 1);
                OString sConverted;
                if (pSuccess)
                    *pSuccess &= sBuf.convertToString(&sConverted, eDestEnc,
                                                      RTL_UNICODETOTEXT_FLAGS_UNDEFINED_ERROR
                                                          | RTL_UNICODETOTEXT_FLAGS_INVALID_ERROR);
                else
                    sBuf.convertToString(&sConverted, eDestEnc, OUSTRING_TO_OSTRING_CVTFLAGS);
                const sal_Int32 nLen = sConverted.getLength();
 
                if (pUCMode && bUnicode)
                {
                    if (*pUCMode != nLen)
                    {
                        aBuf.append("\\uc" + OString::number(nLen));
                        // #i47831# add an additional whitespace, so that "document whitespaces" are not ignored.
                        aBuf.append(' ');
                        *pUCMode = nLen;
                    }
                    aBuf.append("\\u" + OString::number(static_cast<sal_Int32>(c)));
                }
 
                for (sal_Int32 nI = 0; nI < nLen; ++nI)
                {
                    aBuf.append("\\'" + OutHex(sConverted[nI], 2));
                }
            }
    }
    if (pStr)
    {
        aBuf.append(pStr);
        switch (c)
        {
            case 0xa0:
            case 0x1e:
            case 0x1f:
                break;
            default:
                aBuf.append(' ');
        }
    }
    return aBuf.makeStringAndClear();
}
 
OString OutString(std::u16string_view rStr, rtl_TextEncoding eDestEnc, bool bUnicode)
{
    OStringBuffer aBuf;
    int nUCMode = 1;
    for (size_t n = 0; n < rStr.size(); ++n)
        aBuf.append(OutChar(rStr[n], &nUCMode, eDestEnc, nullptr, bUnicode));
    if (nUCMode != 1)
    {
        aBuf.append(
            OOO_STRING_SVTOOLS_RTF_UC + OString::number(sal_Int32(1))
            + " "); // #i47831# add an additional whitespace, so that "document whitespaces" are not ignored.;
    }
    return aBuf.makeStringAndClear();
}
 
/// Checks if lossless conversion of the string to eDestEnc is possible or not.
static bool TryOutString(std::u16string_view rStr, rtl_TextEncoding eDestEnc)
{
    int nUCMode = 1;
    for (size_t n = 0; n < rStr.size(); ++n)
    {
        bool bRet;
        OutChar(rStr[n], &nUCMode, eDestEnc, &bRet);
        if (!bRet)
            return false;
    }
    return true;
}
 
OString OutStringUpr(std::string_view pToken, std::u16string_view rStr, rtl_TextEncoding eDestEnc)
{
    if (TryOutString(rStr, eDestEnc))
        return OString::Concat("{") + pToken + " " + OutString(rStr, eDestEnc) + "}";
 
    return OString::Concat("{" OOO_STRING_SVTOOLS_RTF_UPR "{") + pToken + " "
           + OutString(rStr, eDestEnc, /*bUnicode =*/false)
           + "}{" OOO_STRING_SVTOOLS_RTF_IGNORE OOO_STRING_SVTOOLS_RTF_UD "{" + pToken + " "
           + OutString(rStr, eDestEnc) + "}}}";
}
 
int AsHex(char ch)
{
    int ret = 0;
    if (rtl::isAsciiDigit(static_cast<unsigned char>(ch)))
        ret = ch - '0';
    else
    {
        if (ch >= 'a' && ch <= 'f')
            ret = ch - 'a';
        else if (ch >= 'A' && ch <= 'F')
            ret = ch - 'A';
        else
            return -1;
        ret += 10;
    }
    return ret;
}
 
OString WriteHex(const sal_uInt8* pData, sal_uInt32 nSize, SvStream* pStream, sal_uInt32 nLimit)
{
    OStringBuffer aRet;
 
    sal_uInt32 nBreak = 0;
    for (sal_uInt32 i = 0; i < nSize; i++)
    {
        OString sNo = OString::number(pData[i], 16);
        if (sNo.getLength() < 2)
        {
            if (pStream)
                pStream->WriteChar('0');
            else
                aRet.append('0');
        }
        if (pStream)
            pStream->WriteOString(sNo);
        else
            aRet.append(sNo);
        if (++nBreak == nLimit)
        {
            if (pStream)
                pStream->WriteOString(SAL_NEWLINE_STRING);
            else
                aRet.append(SAL_NEWLINE_STRING);
            nBreak = 0;
        }
    }
 
    return aRet.makeStringAndClear();
}
 
bool ExtractOLE2FromObjdata(const OString& rObjdata, SvStream& rOle2)
{
    SvMemoryStream aStream;
    int b = 0;
    int count = 2;
 
    // Feed the destination text to a stream.
    for (int i = 0; i < rObjdata.getLength(); ++i)
    {
        char ch = rObjdata[i];
        if (ch != 0x0d && ch != 0x0a)
        {
            b = b << 4;
            sal_Int8 parsed = msfilter::rtfutil::AsHex(ch);
            if (parsed == -1)
                return false;
            b += parsed;
            count--;
            if (!count)
            {
                aStream.WriteChar(b);
                count = 2;
                b = 0;
            }
        }
    }
 
    // Skip ObjectHeader, see [MS-OLEDS] 2.2.4.
    if (!aStream.Tell())
        return true;
 
    aStream.Seek(0);
    sal_uInt32 nData;
    aStream.ReadUInt32(nData); // OLEVersion
    aStream.ReadUInt32(nData); // FormatID
    aStream.ReadUInt32(nData); // ClassName
    OString aClassName;
    if (nData)
    {
        // -1 because it is null-terminated.
        aClassName = read_uInt8s_ToOString(aStream, nData - 1);
        // Skip null-termination.
        aStream.SeekRel(1);
    }
    aStream.ReadUInt32(nData); // TopicName
    aStream.SeekRel(nData);
    aStream.ReadUInt32(nData); // ItemName
    aStream.SeekRel(nData);
    aStream.ReadUInt32(nData); // NativeDataSize
 
    if (!nData)
        return true;
 
    sal_uInt64 nPos = aStream.Tell();
    sal_uInt8 aSignature[8];
    aStream.ReadBytes(aSignature, std::size(aSignature));
    aStream.Seek(nPos);
    const sal_uInt8 aOle2Signature[8] = { 0xD0, 0xCF, 0x11, 0xE0, 0xA1, 0xB1, 0x1A, 0xE1 };
    // Don't use Storage::IsStorageFile() here, that would seek to the start of the stream,
    // where the magic will always mismatch.
    if (std::memcmp(aSignature, aOle2Signature, sizeof(aSignature)) == 0)
    {
        // NativeData
        rOle2.WriteStream(aStream, nData);
    }
    else
    {
        SvMemoryStream aStorage;
        WrapOle1InOle2(aStream, nData, aStorage, aClassName);
        rOle2.WriteStream(aStorage);
    }
    rOle2.Seek(0);
 
    return true;
}
 
bool StripMetafileHeader(const sal_uInt8*& rpGraphicAry, sal_uInt64& rSize)
{
    if (rpGraphicAry && (rSize > 0x22))
    {
        if ((rpGraphicAry[0] == 0xd7) && (rpGraphicAry[1] == 0xcd) && (rpGraphicAry[2] == 0xc6)
            && (rpGraphicAry[3] == 0x9a))
        {
            // we have to get rid of the metafileheader
            rpGraphicAry += 22;
            rSize -= 22;
            return true;
        }
    }
    return false;
}
}
 
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */

V530 The return value of function 'append' is required to be utilized.

V530 The return value of function 'append' is required to be utilized.

V530 The return value of function 'append' is required to be utilized.

V530 The return value of function 'append' is required to be utilized.

V530 The return value of function 'append' is required to be utilized.

V530 The return value of function 'OutChar' is required to be utilized.

V530 The return value of function 'append' is required to be utilized.