#include "./vorbiscomment.h"
#include "./vorbiscommentids.h"

#include "../ogg/oggiterator.h"

#include "../diagnostics.h"
#include "../exceptions.h"

#include <c++utilities/io/binaryreader.h>
#include <c++utilities/io/binarywriter.h>
#include <c++utilities/io/copy.h>

#include <map>
#include <memory>

using namespace std;
using namespace CppUtilities;

namespace TagParser {

/*!
 * \class TagParser::VorbisComment
 * \brief Implementation of TagParser::Tag for Vorbis comments.
 */

const TagValue &VorbisComment::value(KnownField field) const
{
    switch (field) {
    case KnownField::Vendor:
        return vendor();
    default:
        return FieldMapBasedTag<VorbisComment>::value(field);
    }
}

bool VorbisComment::setValue(KnownField field, const TagValue &value)
{
    switch (field) {
    case KnownField::Vendor:
        setVendor(value);
        return true;
    default:
        return FieldMapBasedTag<VorbisComment>::setValue(field, value);
    }
}

VorbisComment::IdentifierType VorbisComment::internallyGetFieldId(KnownField field) const
{
    using namespace VorbisCommentIds;
    switch (field) {
    case KnownField::Album:
        return std::string(album());
    case KnownField::Artist:
        return std::string(artist());
    case KnownField::Comment:
        return std::string(comment());
    case KnownField::Cover:
        return std::string(cover());
    case KnownField::RecordDate:
    case KnownField::Year:
        return std::string(date());
    case KnownField::Title:
        return std::string(title());
    case KnownField::Genre:
        return std::string(genre());
    case KnownField::TrackPosition:
        return std::string(trackNumber());
    case KnownField::DiskPosition:
        return std::string(diskNumber());
    case KnownField::PartNumber:
        return std::string(partNumber());
    case KnownField::Composer:
        return std::string(composer());
    case KnownField::Encoder:
        return std::string(encoder());
    case KnownField::EncoderSettings:
        return std::string(encoderSettings());
    case KnownField::Description:
        return std::string(description());
    case KnownField::Grouping:
        return std::string(grouping());
    case KnownField::RecordLabel:
        return std::string(label());
    case KnownField::Performers:
        return std::string(performer());
    case KnownField::Language:
        return std::string(language());
    case KnownField::Lyricist:
        return std::string(lyricist());
    case KnownField::Lyrics:
        return std::string(lyrics());
    case KnownField::AlbumArtist:
        return std::string(albumArtist());
    default:
        return std::string();
    }
}

KnownField VorbisComment::internallyGetKnownField(const IdentifierType &id) const
{
    using namespace VorbisCommentIds;
    // clang-format off
    static const std::map<std::string_view, KnownField, CaseInsensitiveStringComparer> fieldMap({
         { album(), KnownField::Album },
         { artist(), KnownField::Artist },
         { comment(), KnownField::Comment },
         { cover(), KnownField::Cover },
         { date(), KnownField::RecordDate },
         { year(), KnownField::RecordDate },
         { title(), KnownField::Title },
         { genre(), KnownField::Genre },
         { trackNumber(), KnownField::TrackPosition },
         { diskNumber(), KnownField::DiskPosition },
         { partNumber(), KnownField::PartNumber },
         { composer(), KnownField::Composer },
         { encoder(), KnownField::Encoder },
         { encoderSettings(), KnownField::EncoderSettings },
         { description(), KnownField::Description },
         { grouping(), KnownField::Grouping },
         { label(), KnownField::RecordLabel },
         { performer(), KnownField::Performers },
         { lyricist(), KnownField::Lyricist },
         { lyrics(), KnownField::Lyrics },
         { albumArtist(), KnownField::AlbumArtist },
    });
    // clang-format on
    const auto knownField(fieldMap.find(id));
    return knownField != fieldMap.cend() ? knownField->second : KnownField::Invalid;
}

/*!
 * \brief Internal implementation for parsing.
 */
template <class StreamType> void VorbisComment::internalParse(StreamType &stream, std::uint64_t maxSize, VorbisCommentFlags flags, Diagnostics &diag)
{
    // prepare parsing
    static const string context("parsing Vorbis comment");
    std::uint64_t startOffset = static_cast<std::uint64_t>(stream.tellg());
    try {
        // read signature: 0x3 + "vorbis"
        char sig[8];
        bool skipSignature = flags & VorbisCommentFlags::NoSignature;
        if (!skipSignature) {
            CHECK_MAX_SIZE(7)
            stream.read(sig, 7);
            skipSignature = (BE::toUInt64(sig) & 0xffffffffffffff00u) == 0x03766F7262697300u;
        }
        if (skipSignature) {
            // read vendor (length prefixed string)
            {
                CHECK_MAX_SIZE(4)
                stream.read(sig, 4);
                const auto vendorSize = LE::toUInt32(sig);
                if (vendorSize <= maxSize) {
                    auto buff = make_unique<char[]>(vendorSize);
                    stream.read(buff.get(), vendorSize);
                    m_vendor.assignData(move(buff), vendorSize, TagDataType::Text, TagTextEncoding::Utf8);
                    // TODO: Is the vendor string actually UTF-8 (like the field values)?
                } else {
                    diag.emplace_back(DiagLevel::Critical, "Vendor information is truncated.", context);
                    throw TruncatedDataException();
                }
                maxSize -= vendorSize;
            }
            // read field count
            CHECK_MAX_SIZE(4)
            stream.read(sig, 4);
            std::uint32_t fieldCount = LE::toUInt32(sig);
            for (std::uint32_t i = 0; i < fieldCount; ++i) {
                // read fields
                VorbisCommentField field;
                try {
                    field.parse(stream, maxSize, diag);
                    fields().emplace(field.id(), move(field));
                } catch (const TruncatedDataException &) {
                    throw;
                } catch (const Failure &) {
                    // nothing to do here since notifications will be added anyways
                }
            }
            if (!(flags & VorbisCommentFlags::NoFramingByte)) {
                stream.ignore(); // skip framing byte
            }
            m_size = static_cast<std::uint32_t>(static_cast<std::uint64_t>(stream.tellg()) - startOffset);
            // turn "YEAR" into "DATE" (unless "DATE" exists)
            // note: "DATE" is an official field and "YEAR" only an inofficial one but present in some files. In consistency with
            //       MediaInfo and VLC player it is treated like "DATE" here.
            if (fields().find(std::string(VorbisCommentIds::date())) == fields().end()) {
                const auto [first, end] = fields().equal_range(std::string(VorbisCommentIds::year()));
                for (auto i = first; i != end; ++i) {
                    fields().insert(std::pair(VorbisCommentIds::date(), std::move(i->second)));
                }
                fields().erase(first, end);
            }
        } else {
            diag.emplace_back(DiagLevel::Critical, "Signature is invalid.", context);
            throw InvalidDataException();
        }
    } catch (const TruncatedDataException &) {
        m_size = static_cast<std::uint32_t>(static_cast<std::uint64_t>(stream.tellg()) - startOffset);
        diag.emplace_back(DiagLevel::Critical, "Vorbis comment is truncated.", context);
        throw;
    }
}

/*!
 * \brief Parses tag information using the specified OGG \a iterator.
 *
 * \throws Throws std::ios_base::failure when an IO error occurs.
 * \throws Throws TagParser::Failure or a derived exception when a parsing
 *         error occurs.
 */
void VorbisComment::parse(OggIterator &iterator, VorbisCommentFlags flags, Diagnostics &diag)
{
    internalParse(iterator, iterator.streamSize(), flags, diag);
}

/*!
 * \brief Parses tag information using the specified OGG \a iterator.
 *
 * \throws Throws std::ios_base::failure when an IO error occurs.
 * \throws Throws TagParser::Failure or a derived exception when a parsing
 *         error occurs.
 */
void VorbisComment::parse(istream &stream, std::uint64_t maxSize, VorbisCommentFlags flags, Diagnostics &diag)
{
    internalParse(stream, maxSize, flags, diag);
}

/*!
 * \brief Writes tag information to the specified \a stream.
 *
 * \throws Throws std::ios_base::failure when an IO error occurs.
 * \throws Throws TagParser::Failure or a derived exception when a making
 *                error occurs.
 */
void VorbisComment::make(std::ostream &stream, VorbisCommentFlags flags, Diagnostics &diag)
{
    // prepare making
    static const string context("making Vorbis comment");
    string vendor;
    try {
        m_vendor.toString(vendor);
    } catch (const ConversionException &) {
        diag.emplace_back(DiagLevel::Warning, "Can not convert the assigned vendor to string.", context);
    }
    BinaryWriter writer(&stream);
    if (!(flags & VorbisCommentFlags::NoSignature)) {
        // write signature
        static const char sig[7] = { 0x03, 0x76, 0x6F, 0x72, 0x62, 0x69, 0x73 };
        stream.write(sig, sizeof(sig));
    }
    // write vendor
    writer.writeUInt32LE(vendor.size());
    writer.writeString(vendor);
    // write field count later
    const auto fieldCountOffset = stream.tellp();
    writer.writeUInt32LE(0);
    // write fields
    std::uint32_t fieldsWritten = 0;
    for (auto i : fields()) {
        VorbisCommentField &field = i.second;
        if (!field.value().isEmpty()) {
            try {
                if (field.make(writer, flags, diag)) {
                    ++fieldsWritten;
                }
            } catch (const Failure &) {
            }
        }
    }
    // write field count
    const auto framingByteOffset = stream.tellp();
    stream.seekp(fieldCountOffset);
    writer.writeUInt32LE(fieldsWritten);
    stream.seekp(framingByteOffset);
    // write framing byte
    if (!(flags & VorbisCommentFlags::NoFramingByte)) {
        stream.put(0x01);
    }
}

} // namespace TagParser