/* This file is part of Clementine.

   Clementine 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.

   Clementine 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 Clementine.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "magnatuneservice.h"
#include "song.h"

#include <QNetworkAccessManager>
#include <QNetworkRequest>
#include <QNetworkReply>
#include <QXmlStreamReader>
#include <QtIOCompressor>

#include <QtDebug>

const char* MagnatuneService::kServiceName = "Magnatune";
const char* MagnatuneService::kDatabaseUrl =
    "http://magnatune.com/info/song_info2_xml.gz";

MagnatuneService::MagnatuneService(QObject* parent)
  : RadioService(kServiceName, parent),
    root_(NULL),
    network_(new QNetworkAccessManager(this))
{
}

RadioItem* MagnatuneService::CreateRootItem(RadioItem *parent) {
  root_ = new RadioItem(this, RadioItem::Type_Service, kServiceName, parent);
  root_->icon = QIcon(":magnatune.png");
  return root_;
}

void MagnatuneService::LazyPopulate(RadioItem *item) {
  switch (item->type) {
    case RadioItem::Type_Service:
      ReloadDatabase();
      break;

    default:
      break;
  }

  item->lazy_loaded = true;
}

void MagnatuneService::StartLoading(const QUrl& url) {
  emit StreamReady(url, url);
}

void MagnatuneService::ReloadDatabase() {
  QNetworkRequest request = QNetworkRequest(QUrl(kDatabaseUrl));
  request.setRawHeader("User-Agent", QString("%1 %2").arg(
      QCoreApplication::applicationName(), QCoreApplication::applicationVersion()).toUtf8());

  QNetworkReply* reply = network_->get(request);
  connect(reply, SIGNAL(finished()), SLOT(ReloadDatabaseFinished()));
  
  emit TaskStarted(MultiLoadingIndicator::LoadingMagnatune);
}

void MagnatuneService::ReloadDatabaseFinished() {
  QNetworkReply* reply = qobject_cast<QNetworkReply*>(sender());

  emit TaskFinished(MultiLoadingIndicator::LoadingMagnatune);
  root_->lazy_loaded = true;

  if (reply->error() != QNetworkReply::NoError) {
    // TODO: Error handling
    qDebug() << reply->errorString();
    return;
  }

  root_->ClearNotify();

  QtIOCompressor gzip(reply);
  gzip.setStreamFormat(QtIOCompressor::GzipFormat);
  if (!gzip.open(QIODevice::ReadOnly)) {
    qWarning() << "Error opening gzip stream";
    return;
  }

  QXmlStreamReader reader(&gzip);
  while (!reader.atEnd()) {
    reader.readNext();

    if (reader.tokenType() == QXmlStreamReader::StartElement &&
        reader.name() == "Track") {
      ReadTrack(reader);
    }
  }
}

void MagnatuneService::ReadTrack(QXmlStreamReader& reader) {
  QXmlStreamAttributes attributes = reader.attributes();

  Song song;
  song.Init(attributes.value("title").toString(),
            attributes.value("artist").toString(),
            attributes.value("album").toString(),
            attributes.value("seconds").toString().toInt());
  song.set_track(attributes.value("track").toString().toInt());
  song.set_year(attributes.value("year").toString().toInt());
  song.set_filename(attributes.value("url").toString());

  qDebug() << song.artist() << song.album() << song.title();
}