/*

 * Hedgewars, a free turn based strategy game

 * Copyright (c) 2004-2012 Andrey Korotaev <unC0Rr@gmail.com>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; version 2 of the License

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA

 */

#define __STDC_CONSTANT_MACROS

extern "C"

{

#include "libavformat/avformat.h"

}

#include <QVector>

#include <QList>

#include <QMessageBox>

#include <QComboBox>

#include "libav_iteraction.h"

#include "HWApplication.h"

struct Codec

{

    CodecID id;

    bool isAudio;

    QString shortName; // used for identification

    QString longName; // used for displaying to user

    bool isRecomended;

};

struct Format

{

    QString shortName;

    QString longName;

    bool isRecomended;

    QString extension;

    QVector<Codec*> codecs;

};

QList<Codec> codecs;

QMap<QString,Format> formats;

LibavIteraction & LibavIteraction::instance()

{

    static LibavIteraction instance;

    return instance;

}

// test if given format supports given codec

bool FormatQueryCodec(AVOutputFormat *ofmt, enum CodecID codec_id)

{  

#if LIBAVFORMAT_VERSION_MAJOR >= 54

    return avformat_query_codec(ofmt, codec_id, FF_COMPLIANCE_NORMAL) == 1;

#else

    if (ofmt->codec_tag)

        return !!av_codec_get_tag(ofmt->codec_tag, codec_id);

    return codec_id == ofmt->video_codec || codec_id == ofmt->audio_codec;

#endif

}

LibavIteraction::LibavIteraction()

{

    // initialize libav and register all codecs and formats

    av_register_all();

    // get list of all codecs

    AVCodec* pCodec = NULL;

    while (pCodec = av_codec_next(pCodec))

    {

#if LIBAVCODEC_VERSION_MAJOR >= 54

        if (!av_codec_is_encoder(pCodec))

#else

        if (!pCodec->encode)

#endif

            continue;

        if (pCodec->type != AVMEDIA_TYPE_VIDEO && pCodec->type != AVMEDIA_TYPE_AUDIO)

            continue;

        // this encoders seems to be buggy

        if (strcmp(pCodec->name, "rv10") == 0 || strcmp(pCodec->name, "rv20") == 0)

            continue;

        // doesn't support stereo sound

        if (strcmp(pCodec->name, "real_144") == 0)

            continue;

        if (pCodec->type == AVMEDIA_TYPE_VIDEO)

        {

            if (pCodec->supported_framerates != NULL)

                continue;

            // check if codec supports yuv 4:2:0 format

            if (!pCodec->pix_fmts)

                continue;

            bool yuv420Supported = false;

            for (const PixelFormat* pfmt = pCodec->pix_fmts; *pfmt != -1; pfmt++)

                if (*pfmt == PIX_FMT_YUV420P)

                {

                    yuv420Supported = true;

                    break;

                }

            if (!yuv420Supported)

                continue;

        }

        if (pCodec->type == AVMEDIA_TYPE_AUDIO)

        {

            // check if codec supports signed 16-bit format

            if (!pCodec->sample_fmts)

                continue;

            bool s16Supported = false;

            for (const AVSampleFormat* pfmt = pCodec->sample_fmts; *pfmt != -1; pfmt++)

                if (*pfmt == AV_SAMPLE_FMT_S16/* || *pfmt == AV_SAMPLE_FMT_FLT*/)

                {

                    s16Supported = true;

                    break;

                }

            if (!s16Supported)

                continue;

        }

        // add codec to list of codecs

        codecs.push_back(Codec());

        Codec & codec = codecs.back();

        codec.id = pCodec->id;

        codec.isAudio = pCodec->type == AVMEDIA_TYPE_AUDIO;

        codec.shortName = pCodec->name;

        codec.longName = pCodec->long_name;

        codec.isRecomended = false;

        if (strcmp(pCodec->name, "libx264") == 0)

        {

            codec.longName = "H.264/MPEG-4 Part 10 AVC (x264)";

            codec.isRecomended = true;

        }

        else if (strcmp(pCodec->name, "libxvid") == 0)

        {

            codec.longName = "MPEG-4 Part 2 (Xvid)";

            codec.isRecomended = true;

        }

        else if (strcmp(pCodec->name, "libmp3lame") == 0)

        {

            codec.longName = "MP3 (MPEG audio layer 3) (LAME)";

            codec.isRecomended = true;

        }

        else

            codec.longName = pCodec->long_name;

        if (strcmp(pCodec->name, "mpeg4") == 0 || strcmp(pCodec->name, "ac3_fixed") == 0)

            codec.isRecomended = true;

        // FIXME: remove next line

    }

    // get list of all formats

    AVOutputFormat* pFormat = NULL;

    while (pFormat = av_oformat_next(pFormat))

    {

        if (!pFormat->extensions)

            continue;

        // skip some strange formats to not confuse users

        if (strstr(pFormat->long_name, "raw"))

            continue;

        Format format;

        bool hasVideoCodec = false;

        for (QList<Codec>::iterator codec = codecs.begin(); codec != codecs.end(); ++codec)

        {

            if (!FormatQueryCodec(pFormat, codec->id))

                continue;

            format.codecs.push_back(&*codec);

            if (!codec->isAudio)

                hasVideoCodec = true;

        }

        if (!hasVideoCodec)

            continue;

        QString ext(pFormat->extensions);

        ext.truncate(strcspn(pFormat->extensions, ","));

        format.extension = ext;

        format.shortName = pFormat->name;

        format.longName = QString("%1 (*.%2)").arg(pFormat->long_name).arg(ext);

        // FIXME: remove next line

        format.isRecomended = strcmp(pFormat->name, "mp4") == 0 || strcmp(pFormat->name, "avi") == 0;

        formats[pFormat->name] = format;

    }

}

void LibavIteraction::fillFormats(QComboBox * pFormats)

{

    // first insert recomended formats

    foreach(const Format & format, formats)

        if (format.isRecomended)

            pFormats->addItem(format.longName, format.shortName);

    // remember where to place separator between recomended and other formats

    int sep = pFormats->count();

    // insert remaining formats

    foreach(const Format & format, formats)

        if (!format.isRecomended)

            pFormats->addItem(format.longName, format.shortName);

    // insert separator if necessary

    if (sep != 0 && sep != pFormats->count())

        pFormats->insertSeparator(sep);

}

void LibavIteraction::fillCodecs(const QString & fmt, QComboBox * pVCodecs, QComboBox * pACodecs)

{

    Format & format = formats[fmt];

    // first insert recomended codecs

    foreach(Codec * codec, format.codecs)

    {

        if (codec->isRecomended)

        {

            if (codec->isAudio)

                pACodecs->addItem(codec->longName, codec->shortName);

            else

                pVCodecs->addItem(codec->longName, codec->shortName);

        }

    }

    // remember where to place separators between recomended and other codecs

    int vsep = pVCodecs->count();

    int asep = pACodecs->count();

    // insert remaining codecs

    foreach(Codec * codec, format.codecs)

    {

        if (!codec->isRecomended)

        {

            if (codec->isAudio)

                pACodecs->addItem(codec->longName, codec->shortName);

            else

                pVCodecs->addItem(codec->longName, codec->shortName);

        }

    }

    // insert separators if necessary

    if (vsep != 0 && vsep != pVCodecs->count())

        pVCodecs->insertSeparator(vsep);

    if (asep != 0 && asep != pACodecs->count())

        pACodecs->insertSeparator(asep);

}

QString LibavIteraction::getExtension(const QString & format)

{

    return formats[format].extension;

}

QString tr(QString a)

{

    return a;

}

// get information abaout file (duration, resolution etc) in multiline string

QString LibavIteraction::getFileInfo(const QString & filepath)

{

    AVFormatContext* pContext = NULL;

    QByteArray utf8path = filepath.toUtf8();

    if (avformat_open_input(&pContext, utf8path.data(), NULL, NULL) < 0)

        return "";

#if LIBAFORMAT_VERSION_MAJOR < 54

    if (av_find_stream_info(pContext) < 0)

#else

    if (avformat_find_stream_info(pContext, NULL) < 0)

#endif

        return "";

    int s = float(pContext->duration)/AV_TIME_BASE;

    QString desc = QString(tr("Duration: %1m %2s\n")).arg(s/60).arg(s%60);

    for (int i = 0; i < pContext->nb_streams; i++)

    {

        AVStream* pStream = pContext->streams[i];

        if (!pStream)

            continue;

        AVCodecContext* pCodec = pContext->streams[i]->codec;

        if (!pCodec)

            continue;

        if (pCodec->codec_type == AVMEDIA_TYPE_VIDEO)

        {

            desc += QString(tr("Video: %1x%2, ")).arg(pCodec->width).arg(pCodec->height);

            if (pStream->avg_frame_rate.den)

            {

                float fps = float(pStream->avg_frame_rate.num)/pStream->avg_frame_rate.den;

                desc += QString(tr("%1 fps, ")).arg(fps, 0, 'f', 2);

            }

        }

        else if (pCodec->codec_type == AVMEDIA_TYPE_AUDIO)

            desc += tr("Audio: ");

        else

            continue;

        AVCodec* pDecoder = avcodec_find_decoder(pCodec->codec_id);

        desc += pDecoder? pDecoder->name : "unknown";

        desc += "\n";

    }

    AVDictionaryEntry* pComment = av_dict_get(pContext->metadata, "comment", NULL, 0);

    if (pComment)

        desc += QString("\n") + pComment->value;

#if LIBAFORMAT_VERSION_MAJOR < 54

    av_close_input_file(pContext);

#else

    avformat_close_input(&pContext);

#endif

    return desc;

}