/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the Collabora Office 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 <tools/stream.hxx>
#include <tools/XmlWriter.hxx>

#include <libxml/xmlwriter.h>

namespace tools
{
namespace
{
int funcWriteCallback(void* pContext, const char* sBuffer, int nLen)
{
    SvStream* pStream = static_cast<SvStream*>(pContext);
    return static_cast<int>(pStream->WriteBytes(sBuffer, nLen));
}

int funcCloseCallback(void* pContext)
{
    SvStream* pStream = static_cast<SvStream*>(pContext);
    pStream->Flush();
    return 0; // 0 or -1 in case of error
}

template <typename T>
requires(sizeof(T) == sizeof(char)) void attributeBase64_impl(xmlTextWriterPtr writer,
                                                              const char* name, const T* value,
                                                              int size)
{
    (void)xmlTextWriterStartAttribute(writer, BAD_CAST(name));
    (void)xmlTextWriterWriteBase64(writer, reinterpret_cast<const char*>(value), 0, size);
    (void)xmlTextWriterEndAttribute(writer);
}
} // end anonymous namespace

struct XmlWriterImpl
{
    SvStream* mpStream = nullptr;
    xmlTextWriterPtr mpWriter = nullptr;
    bool mbWriteXmlHeader = true;
    bool mbExternalXmlWriter = false;

    XmlWriterImpl(SvStream* pStream)
        : mpStream(pStream)
    {
    }

    XmlWriterImpl(xmlTextWriterPtr pWriter)
        : mpWriter(pWriter)
        , mbWriteXmlHeader(false)
        , mbExternalXmlWriter(true)
    {
    }
};

XmlWriter::XmlWriter(SvStream* pStream)
    : mpImpl(std::make_unique<XmlWriterImpl>(pStream))
{
}

XmlWriter::XmlWriter(xmlTextWriterPtr pWriter)
    : mpImpl(std::make_unique<XmlWriterImpl>(pWriter))
{
}

XmlWriter::~XmlWriter()
{
    if (mpImpl)
        endDocument();
}

bool XmlWriter::startDocument(sal_Int32 nIndent, bool bWriteXmlHeader)
{
    if (mpImpl->mpWriter)
        return false;

    mpImpl->mbWriteXmlHeader = bWriteXmlHeader;
    xmlCharEncodingHandlerPtr pEncodingHandler = xmlGetCharEncodingHandler(XML_CHAR_ENCODING_UTF8);
    xmlOutputBufferPtr xmlOutBuffer = xmlOutputBufferCreateIO(funcWriteCallback, funcCloseCallback,
                                                              mpImpl->mpStream, pEncodingHandler);
    mpImpl->mpWriter = xmlNewTextWriter(xmlOutBuffer);
    if (!mpImpl->mpWriter)
        return false;
    xmlTextWriterSetIndent(mpImpl->mpWriter, nIndent);
    if (mpImpl->mbWriteXmlHeader)
        (void)xmlTextWriterStartDocument(mpImpl->mpWriter, nullptr, "UTF-8", nullptr);

    return true;
}

void XmlWriter::endDocument()
{
    if (!mpImpl->mpWriter || mpImpl->mbExternalXmlWriter)
        return;

    if (mpImpl->mbWriteXmlHeader)
        (void)xmlTextWriterEndDocument(mpImpl->mpWriter);
    xmlFreeTextWriter(mpImpl->mpWriter);
    mpImpl->mpWriter = nullptr;
}

void XmlWriter::startElement(const OString& sPrefix, const OString& sName,
                             const OString& sNamespaceUri)
{
    xmlChar* xmlName = BAD_CAST(sName.getStr());
    xmlChar* xmlPrefix = nullptr;
    xmlChar* xmlNamespaceUri = nullptr;
    if (!sPrefix.isEmpty())
        xmlPrefix = BAD_CAST(sPrefix.getStr());
    if (!sNamespaceUri.isEmpty())
        xmlNamespaceUri = BAD_CAST(sNamespaceUri.getStr());

    (void)xmlTextWriterStartElementNS(mpImpl->mpWriter, xmlPrefix, xmlName, xmlNamespaceUri);
}

void XmlWriter::startElement(const char* pName)
{
    xmlChar* xmlName = BAD_CAST(pName);
    (void)xmlTextWriterStartElement(mpImpl->mpWriter, xmlName);
}

void XmlWriter::endElement() { (void)xmlTextWriterEndElement(mpImpl->mpWriter); }

void XmlWriter::attributeBase64(const char* pName, std::vector<sal_uInt8> const& rValueInBytes)
{
    attributeBase64_impl(mpImpl->mpWriter, pName, rValueInBytes.data(), rValueInBytes.size());
}

void XmlWriter::attributeBase64(const char* pName, std::vector<char> const& rValueInBytes)
{
    attributeBase64_impl(mpImpl->mpWriter, pName, rValueInBytes.data(), rValueInBytes.size());
}

void XmlWriter::attribute(const char* name, std::string_view value)
{
    xmlChar* xmlName = BAD_CAST(name);
    (void)xmlTextWriterWriteFormatAttribute(mpImpl->mpWriter, xmlName, "%.*s", int(value.size()),
                                            value.data());
}

void XmlWriter::attribute(const char* name, std::u16string_view value)
{
    attribute(name, OUStringToOString(value, RTL_TEXTENCODING_UTF8));
}

void XmlWriter::attribute(const char* name, const sal_Int64 aNumber)
{
    attribute(name, OString::number(aNumber));
}

void XmlWriter::attribute(const char* name, const double aNumber)
{
    attribute(name, OString::number(aNumber));
}

void XmlWriter::content(std::string_view value)
{
    (void)xmlTextWriterWriteFormatString(mpImpl->mpWriter, "%.*s", int(value.size()), value.data());
}

void XmlWriter::content(std::u16string_view sValue)
{
    content(OUStringToOString(sValue, RTL_TEXTENCODING_UTF8));
}

void XmlWriter::element(const char* sName)
{
    startElement(sName);
    endElement();
}

} // end tools namespace

/* vim:set shiftwidth=4 softtabstop=4 expandtab: */