#include "MusicPlayer.h"
#include <QDir>
#include <QMediaPlaylist>
#include <controllers/SettingsHandler.h>


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();
    });
    connect(this, &QMediaPlayer::positionChanged, this, [this](qint64){
        emit progressChanged();
    });
    connect(this, &QMediaPlayer::durationChanged, this, [this](qint64){
        emit progressChanged();
        emit mediaLengthChanged();
    });
}

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

    clearPlaylist();

    readMedia(mCurrentItem->getPath());
}

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

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

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

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

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

void MusicPlayer::resetPlaylistToFirstTrack()
{
    if(!playlist() && !playlist()->isEmpty()) return;
    playlist()->setCurrentIndex(0);
}

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
{
    if(duration() <= 0 || position() < 0){
        return 0.0;
    }
    return (double)position()/duration();
}

QString MusicPlayer::getMediaTitle() const
{
    return metaData("Title").toString();
}

QString MusicPlayer::getMediaDuration() const
{
    return millisecondsToString(duration());
}

QString MusicPlayer::getPosition() const
{
    return millisecondsToString(position());
}

void MusicPlayer::clearPlaylist()
{
    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(SettingsHandler::getAudioFileNameFilters());
    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::millisecondsToString(int timeInMilliseconds) const
{
    int seconds = timeInMilliseconds/1000; // ms to secons
    int minutes = seconds/60; //seconds to minutes
    seconds %= 60; // seconds remaining after subtracting minutes
    // format according to [M]M:ss
    // at leading zero to seconds if necessary
    QString secStr = (seconds < 10) ? "0"+QString::number(seconds) : QString::number(seconds);
    return QString::number(minutes) + ":" + secStr;
}