//    This file is part of JustVideo.

//    JustVideo 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, either version 3 of the License, or
//    (at your option) any later version.

//    JustVideo 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.

#include "playlist_backend.h"

PlaylistBE::PlaylistBE(shared_t *share, const QString &path, Player *media, bool frontPlay, QObject *parent) : QObject(nullptr)
{
    Q_UNUSED(parent);

    shared           = share;
    player           = media;
    vidDir           = QDir::cleanPath(path) + QDir::separator();
    buffer           = true;
    startOnMoreMedia = false;
    vidClipBuffer    = 3;
    index            = 0;
    live             = frontPlay;

    auto thr = new QThread(nullptr);

    connect(this, &PlaylistBE::playFile,  media, &Player::setFile);
    connect(this, &PlaylistBE::endOfList, media, &Player::stop);
    connect(this, &PlaylistBE::noMedia,   media, &Player::stop);
    connect(this, &PlaylistBE::buffering, media, &Player::stop);
    connect(this, &PlaylistBE::mPlay,     media, &Player::play);
    connect(this, &PlaylistBE::mStop,     media, &Player::stop);
    connect(this, &PlaylistBE::mPause,    media, &Player::pause);

    connect(thr, &QThread::finished, this, &PlaylistBE::deleteLater);
    connect(thr, &QThread::started,  this, &PlaylistBE::init);

    connect(media, &Player::mediaStatusChanged, this, &PlaylistBE::mediaStatusChanged);
    connect(media, &Player::stateChanged,       this, &PlaylistBE::stateChanged);

    moveToThread(thr);

    thr->start();
}

void PlaylistBE::kill()
{
    thread()->terminate();
}

void PlaylistBE::init()
{
    timer = new QTimer(this);

    timer->setInterval(1000);
    timer->start();

    connect(timer, &QTimer::timeout, this, &PlaylistBE::scan);
}

void PlaylistBE::buffOrEnd()
{
    if (live)
    {
        buffer = true;

        emit buffering();
    }
    else
    {
        emit endOfList();
    }
}

QString PlaylistBE::seek(char direction)
{
    auto ret    = QString();
    auto newInd = index;
    auto max    = fileList.size() - 1;

    if (direction == '+') newInd = index + 1;
    else                  newInd = index - 1;

    if (fileList.isEmpty())
    {
        emit noMedia();

        if (!live)
        {
            startOnMoreMedia = true;
        }
    }
    else if (newInd < 0)
    {
        ret = vidDir + fileList[0];
    }
    else if (newInd <= max)
    {
        index = newInd;
        ret   = vidDir + fileList[index];
    }
    else
    {
        buffOrEnd();
    }

    return ret;
}

void PlaylistBE::list()
{
    for (auto i = 0; i < fileList.size(); ++i)
    {
        emit newFile(vidDir + fileList[i]);
    }
}

void PlaylistBE::next()
{
    emit playFile(seek('+'));
}

void PlaylistBE::prev()
{
    emit playFile(seek('-'));
}

void PlaylistBE::start()
{
    if (!fileList.isEmpty())
    {
        index = 0;

        emit playFile(vidDir + fileList[index]);
    }
    else
    {
        startOnMoreMedia = true; emit noMedia();
    }
}

void PlaylistBE::front()
{
    if (fileList.size() >= vidClipBuffer)
    {
        index  = fileList.size() - vidClipBuffer;
        buffer = false;

        emit playFile(vidDir + fileList[index]);
    }
    else
    {
        buffOrEnd();
    }
}

void PlaylistBE::play()
{
    if (player->state() == QAVPlayer::PausedState)
    {
        emit mPlay();
    }
    else if (player->source().isEmpty())
    {
        next();
    }
}

void PlaylistBE::pause()
{
    emit mPause();
}

void PlaylistBE::stop()
{
    emit mStop();
}

void PlaylistBE::scan()
{
    for (auto &&file : fileList)
    {
        if (!QFileInfo::exists(vidDir + file))
        {
            emit fileDel(vidDir + file);

            fileList.removeOne(file);

            index--;
        }
    }

    auto newVids = lsVidFiles(vidDir);

    for (auto i = 0; i < newVids.size(); ++i)
    {
        if (!fileList.contains(newVids[i]))
        {
            emit newFile(vidDir + newVids[i]);

            fileList.append(newVids[i]);
        }
    }

    if (!fileList.isEmpty())
    {
        if (startOnMoreMedia)
        {
            startOnMoreMedia = false;

            start();
        }
        else if (buffer && live)
        {
            buffer = false;

            next();
        }
    }
}

void PlaylistBE::mediaStatusChanged(QAVPlayer::MediaStatus status)
{
    if (status == QAVPlayer::EndOfMedia || status == QAVPlayer::InvalidMedia)
    {
        next();
    }
}

void PlaylistBE::stateChanged(QAVPlayer::State newState)
{
    if (newState == QAVPlayer::PlayingState)
    {
        emit playbackResumed();
    }
}