/* -*- 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 <pdf/COSWriter.hxx>
#include <rtl/ustring.hxx>
 
namespace vcl::pdf
{
void COSWriter::appendLiteralString(const char* pStr, sal_Int32 nLength)
{
    while (nLength)
    {
        switch (*pStr)
        {
            case '\n':
                mrBuffer.append("\\n");
                break;
            case '\r':
                mrBuffer.append("\\r");
                break;
            case '\t':
                mrBuffer.append("\\t");
                break;
            case '\b':
                mrBuffer.append("\\b");
                break;
            case '\f':
                mrBuffer.append("\\f");
                break;
            case '(':
            case ')':
            case '\\':
                mrBuffer.append("\\");
                mrBuffer.append(static_cast<char>(*pStr));
                break;
            default:
                mrBuffer.append(static_cast<char>(*pStr));
                break;
        }
        pStr++;
        nLength--;
    }
}
 
void COSWriter::writeUnicode(OUString const& rString)
{
    mrBuffer.append("<");
    COSWriter::appendUnicodeTextString(rString, mrBuffer);
    mrBuffer.append(">");
}
 
void COSWriter::writeUnicodeEncrypt(OUString const& rString, sal_Int32 nObject)
{
    if (maParams.mbCanEncrypt && mpPDFEncryptor)
    {
        mrBuffer.append("<");
        const sal_Unicode* pString = rString.getStr();
        size_t nLength = rString.getLength();
        //prepare a unicode string, encrypt it
        mpPDFEncryptor->setupEncryption(maParams.maKey, nObject);
        sal_Int32 nChars = 2 + (nLength * 2);
        std::vector<sal_uInt8> aEncryptionBuffer(nChars);
        sal_uInt8* pCopy = aEncryptionBuffer.data();
        *pCopy++ = 0xFE;
        *pCopy++ = 0xFF;
        // we need to prepare a byte stream from the unicode string buffer
        for (size_t i = 0; i < nLength; i++)
        {
            sal_Unicode aUnicodeChar = pString[i];
            *pCopy++ = sal_uInt8(aUnicodeChar >> 8);
            *pCopy++ = sal_uInt8(aUnicodeChar & 255);
        }
        std::vector<sal_uInt8> aNewBuffer(nChars);
        mpPDFEncryptor->encrypt(aEncryptionBuffer.data(), nChars, aNewBuffer, nChars);
        //now append, hexadecimal (appendHex), the encrypted result
        COSWriter::appendHexArray(aNewBuffer.data(), aNewBuffer.size(), mrBuffer);
        mrBuffer.append(">");
    }
    else
    {
        writeUnicode(rString);
    }
}
 
void COSWriter::writeLiteralEncrypt(std::u16string_view value, sal_Int32 nObject,
                                    rtl_TextEncoding nEncoding)
{
    OString aBufferString(OUStringToOString(value, nEncoding));
    sal_Int32 nLength = aBufferString.getLength();
    OStringBuffer aBuffer(nLength);
    const char* pT = aBufferString.getStr();
 
    for (sal_Int32 i = 0; i < nLength; i++, pT++)
    {
        if ((*pT & 0x80) == 0)
            aBuffer.append(*pT);
        else
        {
            aBuffer.append('<');
            appendHex(*pT, aBuffer);
            aBuffer.append('>');
        }
    }
    writeLiteralEncrypt(aBuffer.makeStringAndClear(), nObject);
}
 
void COSWriter::writeLiteralEncrypt(std::string_view value, sal_Int32 nObject)
{
    if (maParams.mbCanEncrypt && mpPDFEncryptor)
    {
        mrBuffer.append("(");
        size_t nChars = value.size();
        std::vector<sal_uInt8> aEncryptionBuffer(nChars);
        mpPDFEncryptor->setupEncryption(maParams.maKey, nObject);
        mpPDFEncryptor->encrypt(value.data(), nChars, aEncryptionBuffer, nChars);
        appendLiteralString(reinterpret_cast<char*>(aEncryptionBuffer.data()),
                            aEncryptionBuffer.size());
        mrBuffer.append(")");
    }
    else
    {
        writeLiteral(value);
    }
}
 
void COSWriter::appendUnicodeTextString(const OUString& rString, OStringBuffer& rBuffer)
{
    rBuffer.append("FEFF");
    const sal_Unicode* pString = rString.getStr();
    size_t nLength = rString.getLength();
    for (size_t i = 0; i < nLength; i++)
    {
        sal_Unicode aChar = pString[i];
        COSWriter::appendHex(sal_Int8(aChar >> 8), rBuffer);
        COSWriter::appendHex(sal_Int8(aChar & 255), rBuffer);
    }
}
 
void COSWriter::appendName(std::u16string_view rStr, OStringBuffer& rBuffer)
{
    // FIXME i59651 add a check for max length of 127 chars? Per PDF spec 1.4, appendix C.1
    // I guess than when reading the #xx sequence it will count for a single character.
    OString aStr(OUStringToOString(rStr, RTL_TEXTENCODING_UTF8));
    int nLen = aStr.getLength();
    for (int i = 0; i < nLen; i++)
    {
        /*  #i16920# PDF recommendation: output UTF8, any byte
         *  outside the interval [33(=ASCII'!');126(=ASCII'~')]
         *  should be escaped hexadecimal
         *  for the sake of ghostscript which also reads PDF
         *  but has a narrower acceptance rate we only pass
         *  alphanumerics and '-' literally.
         */
        if ((aStr[i] >= 'A' && aStr[i] <= 'Z') || (aStr[i] >= 'a' && aStr[i] <= 'z')
            || (aStr[i] >= '0' && aStr[i] <= '9') || aStr[i] == '-')
        {
            rBuffer.append(aStr[i]);
        }
        else
        {
            rBuffer.append('#');
            appendHex(static_cast<sal_Int8>(aStr[i]), rBuffer);
        }
    }
}
 
void COSWriter::appendName(const char* pStr, OStringBuffer& rBuffer)
{
    // FIXME i59651 see above
    while (pStr && *pStr)
    {
        if ((*pStr >= 'A' && *pStr <= 'Z') || (*pStr >= 'a' && *pStr <= 'z')
            || (*pStr >= '0' && *pStr <= '9') || *pStr == '-')
        {
            rBuffer.append(*pStr);
        }
        else
        {
            rBuffer.append('#');
            appendHex(static_cast<sal_Int8>(*pStr), rBuffer);
        }
        pStr++;
    }
}
 
} //end vcl::pdf
 
/* 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 '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.