#include <qpdf/QPDFObjectHandle_private.hh>

#include <qpdf/ContentNormalizer.hh>
#include <qpdf/JSON_writer.hh>
#include <qpdf/Pipeline.hh>
#include <qpdf/Pipeline_private.hh>
#include <qpdf/Pl_Buffer.hh>
#include <qpdf/Pl_Count.hh>
#include <qpdf/Pl_Discard.hh>
#include <qpdf/Pl_Flate.hh>
#include <qpdf/Pl_QPDFTokenizer.hh>
#include <qpdf/QIntC.hh>
#include <qpdf/QPDFExc.hh>
#include <qpdf/QPDF_private.hh>
#include <qpdf/QTC.hh>
#include <qpdf/QUtil.hh>
#include <qpdf/SF_ASCII85Decode.hh>
#include <qpdf/SF_ASCIIHexDecode.hh>
#include <qpdf/SF_DCTDecode.hh>
#include <qpdf/SF_FlateLzwDecode.hh>
#include <qpdf/SF_RunLengthDecode.hh>

#include <stdexcept>

using namespace std::literals;
using namespace qpdf;

using Streams = QPDF::Doc::Objects::Streams;

class Streams::Copier final: public QPDFObjectHandle::StreamDataProvider
{
    class Data
    {
        friend class Streams;

      public:
        Data(Stream& source, Dictionary const& dest_dict) :
            encp(source.qpdf()->m->encp),
            file(source.qpdf()->m->file),
            source_og(source.id_gen()),
            offset(source.offset()),
            length(source.getLength()),
            dest_dict(dest_dict),
            is_root_metadata(source.isRootMetadata())
        {
        }

      private:
        std::shared_ptr<EncryptionParameters> encp;
        std::shared_ptr<InputSource> file;
        QPDFObjGen source_og;
        qpdf_offset_t offset;
        size_t length;
        QPDFObjectHandle dest_dict;
        bool is_root_metadata{false};
    };

  public:
    Copier() = delete;
    Copier(StreamDataProvider const&) = delete;
    Copier(StreamDataProvider&&) = delete;
    Copier& operator=(StreamDataProvider const&) = delete;
    Copier& operator=(StreamDataProvider&&) = delete;
    ~Copier() final = default;

    Copier(Streams& streams) :
        QPDFObjectHandle::StreamDataProvider(true),
        streams(streams)
    {
    }

    bool
    provideStreamData(
        QPDFObjGen const& og, Pipeline* pipeline, bool suppress_warnings, bool will_retry) final
    {
        auto data = copied_data.find(og);
        if (data != copied_data.end()) {
            auto& fd = data->second;
            QTC::TC("qpdf", "QPDF pipe foreign encrypted stream", fd.encp->encrypted ? 0 : 1);
            if (streams.qpdf.pipeStreamData(
                    fd.encp,
                    fd.file,
                    streams.qpdf,
                    fd.source_og,
                    fd.offset,
                    fd.length,
                    fd.dest_dict,
                    fd.is_root_metadata,
                    pipeline,
                    suppress_warnings,
                    will_retry)) {
                return true; // for CI coverage
            } else {
                return false;
            }
        }
        auto stream = copied_streams.find(og);
        qpdf_invariant(stream == copied_streams.end() || stream->second);
        if (stream != copied_streams.end() &&
            stream->second.pipeStreamData(
                pipeline, nullptr, 0, qpdf_dl_none, suppress_warnings, will_retry)) {
            return true; // for CI coverage
        }
        return false;
    }

    void
    register_copy(Stream& dest, Stream& source, bool provider)
    {
        qpdf_expect(source);
        qpdf_expect(dest);
        if (provider) {
            copied_streams.insert_or_assign(dest, source);
        } else {
            copied_data.insert_or_assign(dest, Data(source, dest.getDict()));
        }
    }

  private:
    Streams& streams;
    std::map<QPDFObjGen, Stream> copied_streams;
    std::map<QPDFObjGen, Data> copied_data;
};

Streams::Streams(Common& common) :
    Common(common),
    copier_(std::make_shared<Copier>(*this))
{
}

namespace
{
    class SF_Crypt final: public QPDFStreamFilter
    {
      public:
        SF_Crypt() = default;
        ~SF_Crypt() final = default;

        bool
        setDecodeParms(QPDFObjectHandle decode_parms) final
        {
            // we only validate here - processing happens in decryptStream
            if (Dictionary dict = decode_parms) {
                for (auto const& [key, value]: dict) {
                    if (key == "/Type" &&
                        (value.null() || Name(value) == "/CryptFilterDecodeParms")) {
                        continue;
                    }
                    if (key == "/Name") {
                        continue;
                    }
                    if (!value.null()) {
                        return false;
                    }
                }
                return true;
            }
            return decode_parms.null();
        }

        Pipeline*
        getDecodePipeline(Pipeline*) final
        {
            // Not used -- handled by pipeStreamData
            return nullptr;
        }
    };

    class StreamBlobProvider
    {
      public:
        StreamBlobProvider(Stream stream, qpdf_stream_decode_level_e decode_level) :
            stream(stream),
            decode_level(decode_level)
        {
        }
        void
        operator()(Pipeline* p)
        {
            stream.pipeStreamData(p, nullptr, 0, decode_level, false, false);
        }

      private:
        Stream stream;
        qpdf_stream_decode_level_e decode_level;
    };

    /// User defined streamfilter factories
    std::map<std::string, std::function<std::shared_ptr<QPDFStreamFilter>()>> filter_factories;
    bool filter_factories_registered = false;
} // namespace

std::string
QPDF_Stream::Members::expand_filter_name(std::string const& name) const
{
    // The PDF specification provides these filter abbreviations for use in inline images, but
    // according to table H.1 in the pre-ISO versions of the PDF specification, Adobe Reader also
    // accepts them for stream filters.
    if (name == "/AHx") {
        return "/ASCIIHexDecode";
    }
    if (name == "/A85") {
        return "/ASCII85Decode";
    }
    if (name == "/LZW") {
        return "/LZWDecode";
    }
    if (name == "/Fl") {
        return "/FlateDecode";
    }
    if (name == "/RL") {
        return "/RunLengthDecode";
    }
    if (name == "/CCF") {
        return "/CCITTFaxDecode";
    }
    if (name == "/DCT") {
        return "/DCTDecode";
    }
    return name;
};

std::function<std::shared_ptr<QPDFStreamFilter>()>
QPDF_Stream::Members::filter_factory(std::string const& name) const
{
    if (filter_factories_registered) [[unlikely]] {
        // We need to check user provided filters first as we allow users to replace qpdf provided
        // default filters. This will have a performance impact if the facility to register stream
        // filters is actually used. We can optimize this away if necessary.
        auto ff = filter_factories.find(expand_filter_name(name));
        if (ff != filter_factories.end()) {
            return ff->second;
        }
    }
    if (name == "/FlateDecode") {
        return SF_FlateLzwDecode::flate_factory;
    }
    if (name == "/Crypt") {
        return []() { return std::make_shared<SF_Crypt>(); };
    }
    if (name == "/LZWDecode") {
        return SF_FlateLzwDecode::lzw_factory;
    }
    if (name == "/RunLengthDecode") {
        return SF_RunLengthDecode::factory;
    }
    if (name == "/DCTDecode") {
        return SF_DCTDecode::factory;
    }
    if (name == "/ASCII85Decode") {
        return SF_ASCII85Decode::factory;
    }
    if (name == "/ASCIIHexDecode") {
        return SF_ASCIIHexDecode::factory;
    }
    // The PDF specification provides these filter abbreviations for use in inline images, but
    // according to table H.1 in the pre-ISO versions of the PDF specification, Adobe Reader
    // also accepts them for stream filters.

    if (name == "/Fl") {
        return SF_FlateLzwDecode::flate_factory;
    }
    if (name == "/AHx") {
        return SF_ASCIIHexDecode::factory;
    }
    if (name == "/A85") {
        return SF_ASCII85Decode::factory;
    }
    if (name == "/LZW") {
        return SF_FlateLzwDecode::lzw_factory;
    }
    if (name == "/RL") {
        return SF_RunLengthDecode::factory;
    }
    if (name == "/DCT") {
        return SF_DCTDecode::factory;
    }
    return nullptr;
}

Stream::Stream(
    QPDF& qpdf, QPDFObjGen og, QPDFObjectHandle stream_dict, qpdf_offset_t offset, size_t length) :
    BaseHandle(QPDFObject::create<QPDF_Stream>(&qpdf, og, std::move(stream_dict), length))
{
    auto descr = std::make_shared<QPDFObject::Description>(
        qpdf.getFilename() + ", stream object " + og.unparse(' '));
    obj->setDescription(&qpdf, descr, offset);
    setDictDescription();
}

Stream
Stream::copy()
{
    Stream result = qpdf()->newStream();
    result.stream()->stream_dict = getDict().copy();
    copy_data_to(result);
    return result;
}

void
Stream::copy_data_to(Stream& dest)
{
    qpdf_expect(dest);
    auto s = stream();
    auto& d_streams = dest.qpdf()->doc().objects().streams();

    auto dict = dest.getDict();

    // Copy information from the foreign stream so we can pipe its data later without keeping the
    // original QPDF object around.
    if (qpdf()->doc().config().immediate_copy_from() && !s->stream_data) {
        // Pull the stream data into a buffer before attempting the copy operation. Do it on the
        // source stream so that if the source stream is copied multiple times, we don't have to
        // keep duplicating the memory. Passing uninitialised object handles will preserve the
        // existing filters and decode parameters.
        replaceStreamData(getRawStreamData(), {}, {});
    }
    if (s->stream_data) {
        dest.replaceStreamData(s->stream_data, dict["/Filter"], dict["/DecodeParms"]);
    } else {
        d_streams.copier()->register_copy(dest, *this, s->stream_provider.get());
        dest.replaceStreamData(d_streams.copier(), dict["/Filter"], dict["/DecodeParms"]);
    }
}

void
Stream::registerStreamFilter(
    std::string const& filter_name, std::function<std::shared_ptr<QPDFStreamFilter>()> factory)
{
    filter_factories[filter_name] = factory;
    filter_factories_registered = true;
}

JSON
Stream::getStreamJSON(
    int json_version,
    qpdf_json_stream_data_e json_data,
    qpdf_stream_decode_level_e decode_level,
    Pipeline* p,
    std::string const& data_filename)
{
    Pl_Buffer pb{"streamjson"};
    JSON::Writer jw{&pb, 0};
    decode_level =
        writeStreamJSON(json_version, jw, json_data, decode_level, p, data_filename, true);
    pb.finish();
    auto result = JSON::parse(pb.getString());
    if (json_data == qpdf_sj_inline) {
        result.addDictionaryMember("data", JSON::makeBlob(StreamBlobProvider(*this, decode_level)));
    }
    return result;
}

qpdf_stream_decode_level_e
Stream::writeStreamJSON(
    int json_version,
    JSON::Writer& jw,
    qpdf_json_stream_data_e json_data,
    qpdf_stream_decode_level_e decode_level,
    Pipeline* p,
    std::string const& data_filename,
    bool no_data_key)
{
    auto s = stream();
    switch (json_data) {
    case qpdf_sj_none:
    case qpdf_sj_inline:
        if (p != nullptr) {
            throw std::logic_error(
                "QPDF_Stream::writeStreamJSON: pipeline should only be supplied "
                "when json_data is file");
        }
        break;
    case qpdf_sj_file:
        if (p == nullptr) {
            throw std::logic_error(
                "QPDF_Stream::writeStreamJSON: pipeline must be supplied when json_data is file");
        }
        if (data_filename.empty()) {
            throw std::logic_error(
                "QPDF_Stream::writeStreamJSON: data_filename must be supplied "
                "when json_data is file");
        }
        break;
    }

    jw.writeStart('{');

    if (json_data == qpdf_sj_none) {
        jw.writeNext();
        jw << R"("dict": )";
        s->stream_dict.writeJSON(json_version, jw);
        jw.writeEnd('}');
        return decode_level;
    }

    Pl_Discard discard;
    Pl_Buffer buf_pl{"stream data"};
    Pipeline* data_pipeline = &buf_pl;
    if (no_data_key && json_data == qpdf_sj_inline) {
        data_pipeline = &discard;
    }
    // pipeStreamData produced valid data.
    bool buf_pl_ready = false;
    bool filtered = false;
    bool filter = (decode_level != qpdf_dl_none);
    for (int attempt = 1; attempt <= 2; ++attempt) {
        bool succeeded =
            pipeStreamData(data_pipeline, &filtered, 0, decode_level, false, (attempt == 1));
        if (!succeeded || (filter && !filtered)) {
            // Try again
            filter = false;
            decode_level = qpdf_dl_none;
            buf_pl.getString(); // reset buf_pl
        } else {
            buf_pl_ready = true;
            break;
        }
    }
    if (!buf_pl_ready) {
        throw std::logic_error("QPDF_Stream: failed to get stream data");
    }
    // We can use unsafeShallowCopy because we are only touching top-level keys.
    auto dict = s->stream_dict.unsafeShallowCopy();
    dict.removeKey("/Length");
    if (filter && filtered) {
        dict.removeKey("/Filter");
        dict.removeKey("/DecodeParms");
    }
    if (json_data == qpdf_sj_file) {
        jw.writeNext() << R"("datafile": ")" << JSON::Writer::encode_string(data_filename) << "\"";
        p->writeString(buf_pl.getString());
    } else if (json_data == qpdf_sj_inline) {
        if (!no_data_key) {
            jw.writeNext() << R"("data": ")";
            jw.writeBase64(buf_pl.getString()) << "\"";
        }
    } else {
        throw std::logic_error("QPDF_Stream::writeStreamJSON : unexpected value of json_data");
    }

    jw.writeNext() << R"("dict": )";
    dict.writeJSON(json_version, jw);
    jw.writeEnd('}');

    return decode_level;
}

void
qpdf::Stream::setDictDescription()
{
    auto s = stream();
    if (!s->stream_dict.hasObjectDescription()) {
        s->stream_dict.setObjectDescription(
            obj->getQPDF(), obj->getDescription() + " -> stream dictionary");
    }
}

std::string
Stream::getStreamData(qpdf_stream_decode_level_e decode_level)
{
    std::string result;
    pl::String buf(result);
    bool filtered;
    pipeStreamData(&buf, &filtered, 0, decode_level, false, false);
    if (!filtered) {
        throw QPDFExc(
            qpdf_e_unsupported,
            qpdf()->getFilename(),
            "",
            offset(),
            "getStreamData called on unfilterable stream");
    }
    return result;
}

std::string
Stream::getRawStreamData()
{
    std::string result;
    pl::String buf(result);
    if (!pipeStreamData(&buf, nullptr, 0, qpdf_dl_none, false, false)) {
        throw QPDFExc(
            qpdf_e_unsupported,
            qpdf()->getFilename(),
            "",
            offset(),
            "error getting raw stream data");
    }
    return result;
}

bool
Stream::isRootMetadata() const
{
    if (!stream()->stream_dict.isDictionaryOfType("/Metadata", "/XML")) {
        return false;
    }
    return qpdf()->getRoot()["/Metadata"].isSameObjectAs(obj);
}

bool
Stream::filterable(
    qpdf_stream_decode_level_e decode_level,
    std::vector<std::shared_ptr<QPDFStreamFilter>>& filters)
{
    auto s = stream();
    // Check filters

    auto const& filter_obj = s->stream_dict["/Filter"];

    if (filter_obj.null()) {
        // No filters
        return true;
    }
    if (filter_obj.size() > global::Limits::max_stream_filters()) {
        global::Limits::error();
        warn(
            "limits error(max-stream-filters): too many filters for stream; treating stream as "
            "not filterable");
        return false;
    }
    if (filter_obj.isName()) {
        // One filter
        auto ff = s->filter_factory(filter_obj.getName());
        if (!ff) {
            return false;
        }
        filters.emplace_back(ff());
    } else if (Array array = filter_obj) {
        // Potentially multiple filters
        for (Name item: array) {
            if (!item) {
                warn("stream filter type is not name or array");
                return false;
            }
            auto ff = s->filter_factory(item);
            if (!ff) {
                filters.clear();
                return false;
            }
            filters.emplace_back(ff());
        }
    } else {
        warn("stream filter type is not name or array");
        return false;
    }

    // filters now contains a list of filters to be applied in order. See which ones we can support.
    // See if we can support any decode parameters that are specified.

    auto decode_obj = s->stream_dict.getKey("/DecodeParms");

    auto can_filter = // linebreak
        [](auto d_level, auto& filter, auto& d_obj) -> bool {
        if (!filter.setDecodeParms(d_obj) ||
            (d_level < qpdf_dl_all && filter.isLossyCompression()) ||
            (d_level < qpdf_dl_specialized && filter.isSpecializedCompression())) {
            return false;
        }
        return true;
    };

    auto decode_array = decode_obj.as_array(strict);
    if (!decode_array || decode_array.size() == 0) {
        if (decode_array) {
            decode_obj = QPDFObjectHandle::newNull();
        }

        for (auto& filter: filters) {
            if (!can_filter(decode_level, *filter, decode_obj)) {
                return false;
            }
        }
    } else {
        // Ignore /DecodeParms entirely if /Filters is empty.  At least one case of a file whose
        // /DecodeParms was [ << >> ] when /Filters was empty has been seen in the wild.
        if (!filters.empty() && QIntC::to_size(decode_array.size()) != filters.size()) {
            warn("stream /DecodeParms length is inconsistent with filters");
            return false;
        }

        int i = -1;
        for (auto& filter: filters) {
            auto d_obj = decode_array.get(++i);
            if (!can_filter(decode_level, *filter, d_obj)) {
                return false;
            }
        }
    }

    return true;
}

bool
Stream::pipeStreamData(
    Pipeline* pipeline,
    bool* filterp,
    int encode_flags,
    qpdf_stream_decode_level_e decode_level,
    bool suppress_warnings,
    bool will_retry)
{
    auto s = stream();
    std::vector<std::shared_ptr<QPDFStreamFilter>> filters;
    bool ignored;
    if (!filterp) {
        filterp = &ignored;
    }
    bool& filter = *filterp;

    const bool empty_stream = !s->stream_provider && !s->stream_data && s->length == 0;
    const bool empty_stream_data = s->stream_data && s->stream_data->getSize() == 0;
    const bool empty = empty_stream || empty_stream_data;

    if (empty_stream || empty_stream_data) {
        filter = true;
    }

    filter = empty || encode_flags || decode_level != qpdf_dl_none;
    if (filter) {
        filter = filterable(decode_level, filters);
    }

    if (!pipeline) {
        QTC::TC("qpdf", "QPDF_Stream pipeStreamData with null pipeline");
        // Return value is whether we can filter in this case.
        return filter;
    }

    // Construct the pipeline in reverse order. Force pipelines we create to be deleted when this
    // function finishes. Pipelines created by QPDFStreamFilter objects will be deleted by those
    // objects.
    std::vector<std::unique_ptr<Pipeline>> to_delete;

    ContentNormalizer normalizer;
    if (filter) {
        if (encode_flags & qpdf_ef_compress) {
            auto new_pipeline =
                std::make_unique<Pl_Flate>("compress stream", pipeline, Pl_Flate::a_deflate);
            pipeline = new_pipeline.get();
            to_delete.push_back(std::move(new_pipeline));
        }

        if (encode_flags & qpdf_ef_normalize) {
            auto new_pipeline =
                std::make_unique<Pl_QPDFTokenizer>("normalizer", &normalizer, pipeline);
            pipeline = new_pipeline.get();
            to_delete.push_back(std::move(new_pipeline));
        }

        for (auto iter = s->token_filters.rbegin(); iter != s->token_filters.rend(); ++iter) {
            auto new_pipeline =
                std::make_unique<Pl_QPDFTokenizer>("token filter", (*iter).get(), pipeline);
            pipeline = new_pipeline.get();
            to_delete.push_back(std::move(new_pipeline));
        }

        for (auto f_iter = filters.rbegin(); f_iter != filters.rend(); ++f_iter) {
            if (auto decode_pipeline = (*f_iter)->getDecodePipeline(pipeline)) {
                pipeline = decode_pipeline;
            }
            auto* flate = dynamic_cast<Pl_Flate*>(pipeline);
            if (flate) {
                flate->setWarnCallback([this](char const* msg, int code) { warn(msg); });
            }
        }
    }

    if (s->stream_data.get()) {
        QTC::TC("qpdf", "QPDF_Stream pipe replaced stream data");
        pipeline->write(s->stream_data->getBuffer(), s->stream_data->getSize());
        pipeline->finish();
    } else if (s->stream_provider.get()) {
        Pl_Count count("stream provider count", pipeline);
        if (s->stream_provider->supportsRetry()) {
            if (!s->stream_provider->provideStreamData(
                    obj->getObjGen(), &count, suppress_warnings, will_retry)) {
                filter = false;
                return false;
            }
        } else {
            s->stream_provider->provideStreamData(obj->getObjGen(), &count);
        }
        qpdf_offset_t actual_length = count.getCount();
        if (s->stream_dict.hasKey("/Length")) {
            auto desired_length = s->stream_dict.getKey("/Length").getIntValue();
            if (actual_length != desired_length) {
                QTC::TC("qpdf", "QPDF_Stream provider length mismatch");
                // This would be caused by programmer error on the part of a library user, not by
                // invalid input data.
                throw std::runtime_error(
                    "stream data provider for " + obj->getObjGen().unparse(' ') + " provided " +
                    std::to_string(actual_length) + " bytes instead of expected " +
                    std::to_string(desired_length) + " bytes");
            }
        } else {
            QTC::TC("qpdf", "QPDF_Stream provider length not provided");
            s->stream_dict.replaceKey("/Length", QPDFObjectHandle::newInteger(actual_length));
        }
    } else {
        if (offset() == 0) {
            throw std::logic_error("pipeStreamData called for stream with no data");
        }
        if (!Streams::pipeStreamData(
                qpdf(),
                id_gen(),
                offset(),
                s->length,
                s->stream_dict,
                isRootMetadata(),
                pipeline,
                suppress_warnings,
                will_retry)) {
            filter = false;
            return false;
        }
    }

    if (filter && !suppress_warnings && normalizer.anyBadTokens()) {
        warn("content normalization encountered bad tokens");
        if (normalizer.lastTokenWasBad()) {
            QTC::TC("qpdf", "QPDF_Stream bad token at end during normalize");
            warn(
                "normalized content ended with a bad token; you may be able to resolve this by "
                "coalescing content streams in combination with normalizing content. From the "
                "command line, specify --coalesce-contents");
        }
        warn(
            "Resulting stream data may be corrupted but is may still useful for manual "
            "inspection. For more information on this warning, search for content normalization "
            "in the manual.");
    }

    return true;
}

void
Stream::replaceStreamData(
    std::string&& data, QPDFObjectHandle const& filter, QPDFObjectHandle const& decode_parms)
{
    auto s = stream();
    s->stream_data = std::make_shared<Buffer>(std::move(data));
    s->stream_provider = nullptr;
    replaceFilterData(filter, decode_parms, s->stream_data->getSize());
}

void
Stream::replaceStreamData(
    std::shared_ptr<Buffer> data,
    QPDFObjectHandle const& filter,
    QPDFObjectHandle const& decode_parms)
{
    auto s = stream();
    s->stream_data = data;
    s->stream_provider = nullptr;
    replaceFilterData(filter, decode_parms, data->size());
}

void
Stream::replaceStreamData(
    std::shared_ptr<QPDFObjectHandle::StreamDataProvider> provider,
    QPDFObjectHandle const& filter,
    QPDFObjectHandle const& decode_parms)
{
    auto s = stream();
    s->stream_provider = provider;
    s->stream_data = nullptr;
    replaceFilterData(filter, decode_parms, 0);
}

void
Stream::replaceFilterData(
    QPDFObjectHandle const& filter, QPDFObjectHandle const& decode_parms, size_t length)
{
    auto s = stream();
    if (filter) {
        s->stream_dict.replaceKey("/Filter", filter);
    }
    if (decode_parms) {
        s->stream_dict.replaceKey("/DecodeParms", decode_parms);
    }
    if (length == 0) {
        QTC::TC("qpdf", "QPDF_Stream unknown stream length");
        s->stream_dict.removeKey("/Length");
    } else {
        s->stream_dict.replaceKey(
            "/Length", QPDFObjectHandle::newInteger(QIntC::to_longlong(length)));
    }
}

void
Stream::warn(std::string const& message)
{
    qpdf()->warn(qpdf_e_damaged_pdf, "", offset(), message);
}

QPDFObjectHandle
QPDFObjectHandle::getDict() const
{
    return as_stream(error).getDict();
}

void
QPDFObjectHandle::setFilterOnWrite(bool val)
{
    as_stream(error).setFilterOnWrite(val);
}

bool
QPDFObjectHandle::getFilterOnWrite()
{
    return as_stream(error).getFilterOnWrite();
}

bool
QPDFObjectHandle::isDataModified()
{
    return as_stream(error).isDataModified();
}

void
QPDFObjectHandle::replaceDict(QPDFObjectHandle const& new_dict)
{
    as_stream(error).replaceDict(new_dict);
}

bool
QPDFObjectHandle::isRootMetadata() const
{
    return as_stream(error).isRootMetadata();
}

std::shared_ptr<Buffer>
QPDFObjectHandle::getStreamData(qpdf_stream_decode_level_e level)
{
    return std::make_shared<Buffer>(as_stream(error).getStreamData(level));
}

std::shared_ptr<Buffer>
QPDFObjectHandle::getRawStreamData()
{
    return std::make_shared<Buffer>(as_stream(error).getRawStreamData());
}

bool
QPDFObjectHandle::pipeStreamData(
    Pipeline* p,
    bool* filtering_attempted,
    int encode_flags,
    qpdf_stream_decode_level_e decode_level,
    bool suppress_warnings,
    bool will_retry)
{
    return as_stream(error).pipeStreamData(
        p, filtering_attempted, encode_flags, decode_level, suppress_warnings, will_retry);
}

bool
QPDFObjectHandle::pipeStreamData(
    Pipeline* p,
    int encode_flags,
    qpdf_stream_decode_level_e decode_level,
    bool suppress_warnings,
    bool will_retry)
{
    bool filtering_attempted;
    as_stream(error).pipeStreamData(
        p, &filtering_attempted, encode_flags, decode_level, suppress_warnings, will_retry);
    return filtering_attempted;
}

bool
QPDFObjectHandle::pipeStreamData(Pipeline* p, bool filter, bool normalize, bool compress)
{
    int encode_flags = 0;
    qpdf_stream_decode_level_e decode_level = qpdf_dl_none;
    if (filter) {
        decode_level = qpdf_dl_generalized;
        if (normalize) {
            encode_flags |= qpdf_ef_normalize;
        }
        if (compress) {
            encode_flags |= qpdf_ef_compress;
        }
    }
    return pipeStreamData(p, encode_flags, decode_level, false);
}

void
QPDFObjectHandle::replaceStreamData(
    std::shared_ptr<Buffer> data,
    QPDFObjectHandle const& filter,
    QPDFObjectHandle const& decode_parms)
{
    as_stream(error).replaceStreamData(data, filter, decode_parms);
}

void
QPDFObjectHandle::replaceStreamData(
    std::string const& data, QPDFObjectHandle const& filter, QPDFObjectHandle const& decode_parms)
{
    std::string s(data);
    as_stream(error).replaceStreamData(std::move(s), filter, decode_parms);
}

void
QPDFObjectHandle::replaceStreamData(
    std::shared_ptr<StreamDataProvider> provider,
    QPDFObjectHandle const& filter,
    QPDFObjectHandle const& decode_parms)
{
    as_stream(error).replaceStreamData(provider, filter, decode_parms);
}

namespace
{
    class FunctionProvider: public QPDFObjectHandle::StreamDataProvider
    {
      public:
        FunctionProvider(std::function<void(Pipeline*)> provider) :
            StreamDataProvider(false),
            p1(provider),
            p2(nullptr)
        {
        }
        FunctionProvider(std::function<bool(Pipeline*, bool, bool)> provider) :
            StreamDataProvider(true),
            p1(nullptr),
            p2(provider)
        {
        }

        void
        provideStreamData(QPDFObjGen const&, Pipeline* pipeline) override
        {
            p1(pipeline);
        }

        bool
        provideStreamData(
            QPDFObjGen const&, Pipeline* pipeline, bool suppress_warnings, bool will_retry) override
        {
            return p2(pipeline, suppress_warnings, will_retry);
        }

      private:
        std::function<void(Pipeline*)> p1;
        std::function<bool(Pipeline*, bool, bool)> p2;
    };
} // namespace

void
QPDFObjectHandle::replaceStreamData(
    std::function<void(Pipeline*)> provider,
    QPDFObjectHandle const& filter,
    QPDFObjectHandle const& decode_parms)
{
    auto sdp = std::shared_ptr<StreamDataProvider>(new FunctionProvider(provider));
    as_stream(error).replaceStreamData(sdp, filter, decode_parms);
}

void
QPDFObjectHandle::replaceStreamData(
    std::function<bool(Pipeline*, bool, bool)> provider,
    QPDFObjectHandle const& filter,
    QPDFObjectHandle const& decode_parms)
{
    auto sdp = std::shared_ptr<StreamDataProvider>(new FunctionProvider(provider));
    as_stream(error).replaceStreamData(sdp, filter, decode_parms);
}

JSON
QPDFObjectHandle::getStreamJSON(
    int json_version,
    qpdf_json_stream_data_e json_data,
    qpdf_stream_decode_level_e decode_level,
    Pipeline* p,
    std::string const& data_filename)
{
    return as_stream(error).getStreamJSON(json_version, json_data, decode_level, p, data_filename);
}

QPDFObjectHandle
QPDFObjectHandle::copyStream()
{
    return as_stream(error).copy();
}