#include "MusicPlayer.h"
#include <QDir>
#include <QMediaPlaylist>



MusicPlayer::MusicPlayer(QObject *parent) : QMediaPlayer(parent)
{
    // init audio
    /// @todo remove magic number
    setVolume(50);
    // relay signal to qml
    connect(this, &QMediaPlayer::stateChanged, this, &MusicPlayer::isPlayingChanged);
    connect(this, &QMediaPlayer::currentMediaChanged, this, [this](const QMediaContent&){
        // notify qml to refresh enable state of next and previous button
        emit hasNextChanged();
        emit hasPreviousChanged();
    });
}

void MusicPlayer::init(NavigationItemModel *item)
{
    if(mCurrentItem == item){
        return;
    }
    mCurrentItem = item;
    emit coverImageSourceChanged();

    reset();
    clearMediaList();

    readMedia(mCurrentItem->getPath());
}

void MusicPlayer::navigateBack()
{
    emit navigateTo(mCurrentItem);
}

void MusicPlayer::playPause()
{
    if(isPlaying())
        pause();
    else
        play();
}

void MusicPlayer::stopMusic()
{
    if(isPlaying()){
       reset();
       stop();
    }
}

void MusicPlayer::playNext()
{
    if(!hasNext()) return; // checks if playlist exists
    playlist()->next();
}

void MusicPlayer::playPrevious()
{
    if(!hasPrevious()) return;
    playlist()->previous();
}

bool MusicPlayer::isPlaying() const
{
    return state() == State::PlayingState;
}

bool MusicPlayer::hasNext() const
{
    if(!playlist()) return false;
    const auto nextIndex = playlist()->nextIndex();
    /* player yields -1 as next index while playing last track
     */
    return nextIndex >=0 && nextIndex < playlist()->mediaCount();
}

bool MusicPlayer::hasPrevious() const
{
    if(!playlist()) return false;
    const auto previousIndex = playlist()->previousIndex();
    /* player inits with currentIndex -1 and hence previousIndex = last index
     * until started. Yet, previousButton should initially be disabled.
     */
    return  previousIndex >= 0 && previousIndex < playlist()->currentIndex();
}

double MusicPlayer::getProgress() const
{
    return mCurrentMediaItemProgress;
}

QString MusicPlayer::getMediaTitle() const
{
    return mMediaTitle;
}

QString MusicPlayer::getMediaLength()
{
    return timeToString(mCurrentMediaItemLength);
}

QString MusicPlayer::getTime()
{
    return timeToString(mCurrentTime);
}

void MusicPlayer::onTimeChanged(int time)
{
    mCurrentMediaItemProgress = (double) time / mCurrentMediaItemLength;
    mCurrentTime = time;
    emit progressChanged();
}

void MusicPlayer::onLengthChanged(int length)
{
    mCurrentMediaItemLength= length;
    emit mediaLengthChanged();
}

void MusicPlayer::reset()
{
    mCurrentMediaItemProgress = 0.0;
    mCurrentTime = 0.0;
    emit progressChanged();

    mCurrentMediaItemLength = 0.0;
    emit mediaLengthChanged();
}

void MusicPlayer::clearMediaList()
{
    if(playlist()){
        playlist()->clear();
    }
}

void MusicPlayer::readMedia(const QString& path)
{
    auto dir = QDir(path);
    if(!dir.exists()) return;

    // create playlist if necessary
    auto playList = playlist();
    if(!playList){
        playList = new QMediaPlaylist(this);
        setPlaylist(playList);
    }

    // add audio files to playlist
    dir.setNameFilters({"*.mp3", "*.flac"});
    auto files = dir.entryInfoList(QDir::Files);
    for(auto file:files){
        auto fileName = file.absoluteFilePath();
        auto fileUrl = QUrl::fromLocalFile(fileName);
        playList->addMedia(QMediaContent(fileUrl));
    }
}

QString MusicPlayer::timeToString(int time)
{
    int sec = time/1000;
    int min = sec/60;
    sec = sec-min*60;
    QString secStr = (sec < 10) ? "0"+QString::number(sec) : QString::number(sec);
    return QString::number(min) + ":" + secStr;
}