/* This file is part of Clementine.
   Copyright 2010, David Sansome <me@davidsansome.com>

   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 "nowplayingwidget.h"

#include <QGuiApplication>
#include <QMenu>
#include <QMovie>
#include <QPaintEvent>
#include <QPainter>
#include <QScreen>
#include <QSettings>
#include <QTextDocument>
#include <QTimeLine>
#include <QWindow>
#include <QtDebug>

#include "core/application.h"
#include "core/logging.h"
#include "covers/albumcoverloader.h"
#include "covers/coverproviders.h"
#include "covers/currentartloader.h"
#include "covers/kittenloader.h"
#include "fullscreenhypnotoad.h"
#include "library/librarybackend.h"
#include "networkremote/networkremote.h"
#include "ui/albumcoverchoicecontroller.h"
#include "ui/iconloader.h"

const char* NowPlayingWidget::kSettingsGroup = "NowPlayingWidget";

const char* NowPlayingWidget::kHypnotoadPath = ":/hypnotoad.gif";

// Space between the cover and the details in small mode
const int NowPlayingWidget::kPadding = 2;

// Width of the transparent to black gradient above and below the text in large
// mode
const int NowPlayingWidget::kGradientHead = 40;
const int NowPlayingWidget::kGradientTail = 20;

// Maximum height of the cover in large mode, and offset between the
// bottom of the cover and bottom of the widget
const int NowPlayingWidget::kMaxCoverSize = 260;
const int NowPlayingWidget::kBottomOffset = 0;

// Border for large mode
const int NowPlayingWidget::kTopBorder = 4;

NowPlayingWidget::NowPlayingWidget(QWidget* parent)
    : QWidget(parent),
      app_(nullptr),
      album_cover_choice_controller_(new AlbumCoverChoiceController(this)),
      mode_(SmallSongDetails),
      menu_(new QMenu(this)),
      above_statusbar_action_(nullptr),
      fit_cover_width_action_(nullptr),
      visible_(false),
      small_ideal_height_(0),
      fit_width_(false),
      show_hide_animation_(new QTimeLine(500, this)),
      fade_animation_(new QTimeLine(1000, this)),
      details_(new QTextDocument(this)),
      previous_track_opacity_(0.0),
      bask_in_his_glory_action_(nullptr),
      downloading_covers_(false),
      aww_(false),
      kittens_(nullptr),
      pending_kitten_(0) {
  // Load settings
  QSettings s;
  s.beginGroup(kSettingsGroup);
  mode_ = Mode(s.value("mode", SmallSongDetails).toInt());
  album_cover_choice_controller_->search_cover_auto_action()->setChecked(
      s.value("search_for_cover_auto", false).toBool());
  fit_width_ = s.value("fit_cover_width", false).toBool();

  // Accept drops for setting album art
  setAcceptDrops(true);

  // Context menu
  QActionGroup* mode_group = new QActionGroup(this);
  CreateModeAction(SmallSongDetails, tr("Small album cover"), mode_group);
  CreateModeAction(LargeSongDetails, tr("Large album cover"), mode_group);
  CreateModeAction(LargeSongDetailsBelow,
                   tr("Large album cover (details below)"), mode_group);
  CreateModeAction(LargeNoSongDetails, tr("Large album cover (no details)"),
                   mode_group);

  menu_->addActions(mode_group->actions());

  fit_cover_width_action_ = menu_->addAction(tr("Fit cover to width"));

  fit_cover_width_action_->setCheckable(true);
  fit_cover_width_action_->setEnabled(mode_ != SmallSongDetails);
  connect(fit_cover_width_action_, SIGNAL(toggled(bool)),
          SLOT(FitCoverWidth(bool)));
  fit_cover_width_action_->setChecked(fit_width_);
  menu_->addSeparator();

  QList<QAction*> actions = album_cover_choice_controller_->GetAllActions();

  // Here we add the search automatically action, too!
  actions.append(album_cover_choice_controller_->search_cover_auto_action());

  connect(album_cover_choice_controller_->cover_from_file_action(),
          SIGNAL(triggered()), this, SLOT(LoadCoverFromFile()));
  connect(album_cover_choice_controller_->cover_to_file_action(),
          SIGNAL(triggered()), this, SLOT(SaveCoverToFile()));
  connect(album_cover_choice_controller_->cover_from_url_action(),
          SIGNAL(triggered()), this, SLOT(LoadCoverFromURL()));
  connect(album_cover_choice_controller_->search_for_cover_action(),
          SIGNAL(triggered()), this, SLOT(SearchForCover()));
  connect(album_cover_choice_controller_->unset_cover_action(),
          SIGNAL(triggered()), this, SLOT(UnsetCover()));
  connect(album_cover_choice_controller_->show_cover_action(),
          SIGNAL(triggered()), this, SLOT(ShowCover()));
  connect(album_cover_choice_controller_->search_cover_auto_action(),
          SIGNAL(triggered()), this, SLOT(SearchCoverAutomatically()));

  menu_->addActions(actions);
  menu_->addSeparator();
  above_statusbar_action_ = menu_->addAction(tr("Show above status bar"));

  above_statusbar_action_->setCheckable(true);
  connect(above_statusbar_action_, SIGNAL(toggled(bool)),
          SLOT(ShowAboveStatusBar(bool)));
  above_statusbar_action_->setChecked(
      s.value("above_status_bar", false).toBool());

  bask_in_his_glory_action_ =
      menu_->addAction(tr("ALL GLORY TO THE HYPNOTOAD"));
  bask_in_his_glory_action_->setVisible(false);
  connect(bask_in_his_glory_action_, SIGNAL(triggered()), SLOT(Bask()));

  // Animations
  connect(show_hide_animation_, SIGNAL(frameChanged(int)),
          SLOT(SetHeight(int)));
  setMaximumHeight(0);

  connect(fade_animation_, SIGNAL(valueChanged(qreal)),
          SLOT(FadePreviousTrack(qreal)));
  fade_animation_->setDirection(QTimeLine::Backward);  // 1.0 -> 0.0

  // add placeholder text to get the correct height
  if (mode_ == LargeSongDetailsBelow) {
    details_->setDefaultStyleSheet(
        "p {"
        "  font-size: small;"
        "  color: white;"
        "}");
    details_->setHtml(QString("<p align=center><i></i><br/><br/></p>"));
  }

  UpdateHeight();

  connect(album_cover_choice_controller_, SIGNAL(AutomaticCoverSearchDone()),
          this, SLOT(AutomaticCoverSearchDone()));
}

NowPlayingWidget::~NowPlayingWidget() {}

void NowPlayingWidget::SetApplication(Application* app) {
  app_ = app;

  album_cover_choice_controller_->SetApplication(app_);
  connect(app_->current_art_loader(), SIGNAL(ArtLoaded(Song, QString, QImage)),
          SLOT(AlbumArtLoaded(Song, QString, QImage)));
}

void NowPlayingWidget::CreateModeAction(Mode mode, const QString& text,
                                        QActionGroup* group) {
  QAction* action = new QAction(text, group);
  action->setCheckable(true);
  connect(action, &QAction::triggered, [this, mode]() { SetMode(mode); });

  if (mode == mode_) action->setChecked(true);
}

void NowPlayingWidget::set_ideal_height(int height) {
  small_ideal_height_ = height;
  UpdateHeight();
}

QSize NowPlayingWidget::sizeHint() const {
  return QSize(cover_loader_options_.desired_height_, total_height_);
}

void NowPlayingWidget::UpdateHeight() {
  switch (mode_) {
    case SmallSongDetails:
      cover_loader_options_.desired_height_ = small_ideal_height_;
      total_height_ = small_ideal_height_;
      break;

    case LargeSongDetails:
    case LargeNoSongDetails:
      if (fit_width_) {
        cover_loader_options_.desired_height_ = width();
      } else {
        cover_loader_options_.desired_height_ = qMin(kMaxCoverSize, width());
      }
      total_height_ =
          kTopBorder + cover_loader_options_.desired_height_ + kBottomOffset;
      break;

    case LargeSongDetailsBelow:
      if (fit_width_) {
        cover_loader_options_.desired_height_ = width();
      } else {
        cover_loader_options_.desired_height_ = qMin(kMaxCoverSize, width());
      }
      total_height_ = kTopBorder + cover_loader_options_.desired_height_ +
                      kBottomOffset + details_->size().height();
      break;
  }

  // Update the animation settings and resize the widget now if we're visible
  show_hide_animation_->setFrameRange(0, total_height_);
  if (visible_ && show_hide_animation_->state() != QTimeLine::Running)
    setMaximumHeight(total_height_);

  // Re-scale the current image
  if (metadata_.is_valid()) {
    ScaleCover();
  }

  // Tell Qt we've changed size
  updateGeometry();
}

void NowPlayingWidget::Stopped() { SetVisible(false); }

void NowPlayingWidget::UpdateDetailsText() {
  QString html;

  switch (mode_) {
    case SmallSongDetails:
    case LargeNoSongDetails:
      details_->setTextWidth(-1);
      details_->setDefaultStyleSheet("");
      html += "<p>";
      break;

    case LargeSongDetails:
      details_->setTextWidth(cover_loader_options_.desired_height_);
      details_->setDefaultStyleSheet(
          "p {"
          "  font-size: small;"
          "  color: white;"
          "}");
      html += "<p align=center>";
      break;

    case LargeSongDetailsBelow:
      details_->setTextWidth(cover_loader_options_.desired_height_);
      if (fit_width_) {
        details_->setDefaultStyleSheet(
            "p {"
            "  font-size: small;"
            "}");
      } else {
        details_->setDefaultStyleSheet(
            "p {"
            "  font-size: small;"
            "  color: white;"
            "}");
      }
      html += "<p align=center>";
      break;
  }

  // TODO: Make this configurable
  html += QString("<i>%1</i><br/>%2<br/>%3")
              .arg(metadata_.PrettyTitle().toHtmlEscaped(),
                   metadata_.artist().toHtmlEscaped(),
                   metadata_.album().toHtmlEscaped());

  html += "</p>";
  details_->setHtml(html);

  // if something spans multiple lines the height needs to change
  if (mode_ == LargeSongDetailsBelow) {
    UpdateHeight();
  }
}

void NowPlayingWidget::ScaleCover() {
  cover_ = QPixmap::fromImage(
      AlbumCoverLoader::ScaleAndPad(cover_loader_options_, original_));
  update();
}

void NowPlayingWidget::KittenLoaded(quint64 id, const QImage& image) {
  if (aww_ && pending_kitten_ == id) {
    SetImage(image);
  }
}

void NowPlayingWidget::AlbumArtLoaded(const Song& metadata, const QString& uri,
                                      const QImage& image) {
  metadata_ = metadata;
  downloading_covers_ = false;

  if (aww_) {
    pending_kitten_ =
        kittens_->LoadKitten(app_->current_art_loader()->options());
    return;
  }

  SetImage(image);

  // Search for cover automatically?
  GetCoverAutomatically();
}

void NowPlayingWidget::SetImage(const QImage& image) {
  if (visible_) {
    // Cache the current pixmap so we can fade between them
    previous_track_ = QPixmap(size());
    previous_track_.fill(palette().window().color());
    previous_track_opacity_ = 1.0;
    QPainter p(&previous_track_);
    DrawContents(&p);
    p.end();
  }

  original_ = image;

  UpdateDetailsText();
  ScaleCover();
  SetVisible(true);

  // Were we waiting for this cover to load before we started fading?
  if (!previous_track_.isNull()) {
    fade_animation_->start();
  }
}

void NowPlayingWidget::SetHeight(int height) { setMaximumHeight(height); }

void NowPlayingWidget::SetVisible(bool visible) {
  if (visible == visible_) return;
  visible_ = visible;

  show_hide_animation_->setDirection(visible ? QTimeLine::Forward
                                             : QTimeLine::Backward);
  show_hide_animation_->start();
}

void NowPlayingWidget::paintEvent(QPaintEvent* e) {
  QPainter p(this);

  DrawContents(&p);

  // Draw the previous track's image if we're fading
  if (!previous_track_.isNull()) {
    p.setOpacity(previous_track_opacity_);
    p.drawPixmap(0, 0, previous_track_);
  }
}

void NowPlayingWidget::DrawContents(QPainter* p) {
  switch (mode_) {
    case SmallSongDetails:
      if (hypnotoad_) {
        p->drawPixmap(0, 0, small_ideal_height_, small_ideal_height_,
                      hypnotoad_->currentPixmap());
      } else {
        // Draw the cover
        p->drawPixmap(0, 0, small_ideal_height_, small_ideal_height_, cover_);
        if (downloading_covers_) {
          p->drawPixmap(small_ideal_height_ - 18, 6, 16, 16,
                        spinner_animation_->currentPixmap());
        }
      }

      // Draw the details
      p->translate(small_ideal_height_ + kPadding, 0);
      details_->drawContents(p);
      p->translate(-small_ideal_height_ - kPadding, 0);
      break;

    case LargeSongDetails: {
      const int total_size =
          fit_width_ ? width() : qMin(kMaxCoverSize, width());
      const int x_offset =
          (width() - cover_loader_options_.desired_height_) / 2;

      // Draw the black background
      p->fillRect(QRect(0, kTopBorder, width(), height() - kTopBorder),
                  Qt::black);

      // Draw the cover
      if (hypnotoad_) {
        p->drawPixmap(x_offset, kTopBorder, total_size, total_size,
                      hypnotoad_->currentPixmap());
      } else {
        p->drawPixmap(x_offset, kTopBorder, total_size, total_size, cover_);
        if (downloading_covers_) {
          p->drawPixmap(x_offset + 45, 35, 16, 16,
                        spinner_animation_->currentPixmap());
        }
      }

      // Work out how high the text is going to be
      const int text_height = details_->size().height();
      const int gradient_mid = height() - qMax(text_height, kBottomOffset);

      // Draw the black fade
      QLinearGradient gradient(0, gradient_mid - kGradientHead, 0,
                               gradient_mid + kGradientTail);
      gradient.setColorAt(0, QColor(0, 0, 0, 0));
      gradient.setColorAt(1, QColor(0, 0, 0, 255));

      p->fillRect(0, gradient_mid - kGradientHead, width(),
                  height() - (gradient_mid - kGradientHead), gradient);

      // Draw the text on top
      p->translate(x_offset, height() - text_height);
      details_->drawContents(p);
      p->translate(-x_offset, -height() + text_height);
      break;
    }

    case LargeNoSongDetails: {
      const int total_size =
          fit_width_ ? width() : qMin(kMaxCoverSize, width());
      const int x_offset =
          (width() - cover_loader_options_.desired_height_) / 2;

      // Draw the black background
      p->fillRect(QRect(0, kTopBorder, width(), height() - kTopBorder),
                  Qt::black);

      // Draw the cover
      if (hypnotoad_) {
        p->drawPixmap(x_offset, kTopBorder, total_size, total_size,
                      hypnotoad_->currentPixmap());
      } else {
        p->drawPixmap(x_offset, kTopBorder, total_size, total_size, cover_);
        if (downloading_covers_) {
          p->drawPixmap(x_offset + 45, 35, 16, 16,
                        spinner_animation_->currentPixmap());
        }
      }
      break;
    }

    case LargeSongDetailsBelow:
      // Work out how high the text is going to be
      const int text_height = details_->size().height();

      const int cover_size =
          fit_width_ ? width() : qMin(kMaxCoverSize, width());
      const int x_offset =
          (width() - cover_loader_options_.desired_height_) / 2;

      if (!fit_width_) {
        // Draw the black background
        p->fillRect(QRect(0, kTopBorder, width(), height() - kTopBorder),
                    Qt::black);
      }

      // Draw the cover
      if (hypnotoad_) {
        p->drawPixmap(x_offset, kTopBorder, cover_size, cover_size,
                      hypnotoad_->currentPixmap());
      } else {
        p->drawPixmap(x_offset, kTopBorder, cover_size, cover_size, cover_);
        if (downloading_covers_) {
          p->drawPixmap(x_offset + 45, 35, 16, 16,
                        spinner_animation_->currentPixmap());
        }
      }

      // Draw the text below
      p->translate(x_offset, height() - text_height);
      details_->drawContents(p);
      p->translate(-x_offset, -height() + text_height);
      break;
  }
}

void NowPlayingWidget::FadePreviousTrack(qreal value) {
  previous_track_opacity_ = value;
  if (qFuzzyCompare(previous_track_opacity_, qreal(0.0))) {
    previous_track_ = QPixmap();
  }

  update();
}

void NowPlayingWidget::SetMode(int mode) {
  mode_ = Mode(mode);

  if (mode_ == SmallSongDetails) {
    fit_cover_width_action_->setEnabled(false);
  } else {
    fit_cover_width_action_->setEnabled(true);
  }

  UpdateHeight();
  UpdateDetailsText();
  update();

  QSettings s;
  s.beginGroup(kSettingsGroup);
  s.setValue("mode", mode_);
}

void NowPlayingWidget::resizeEvent(QResizeEvent* e) {
  if (visible_ && e->oldSize() != e->size()) {
    if (mode_ == LargeSongDetails || mode_ == LargeNoSongDetails ||
        mode_ == LargeSongDetailsBelow) {
      UpdateHeight();
      UpdateDetailsText();
    }
  }
}

void NowPlayingWidget::contextMenuEvent(QContextMenuEvent* e) {
  // initial 'enabled' values depending on the kitty mode
  album_cover_choice_controller_->cover_from_file_action()->setEnabled(!aww_);
  album_cover_choice_controller_->cover_from_url_action()->setEnabled(!aww_);
  album_cover_choice_controller_->search_for_cover_action()->setEnabled(
      !aww_ && app_->cover_providers()->HasAnyProviders());
  album_cover_choice_controller_->unset_cover_action()->setEnabled(!aww_);
  album_cover_choice_controller_->show_cover_action()->setEnabled(!aww_);

  // some special cases
  if (!aww_) {
    const bool art_is_not_set = metadata_.has_manually_unset_cover() ||
                                (metadata_.art_automatic().isEmpty() &&
                                 metadata_.art_manual().isEmpty());

    album_cover_choice_controller_->unset_cover_action()->setEnabled(
        !art_is_not_set);
    album_cover_choice_controller_->show_cover_action()->setEnabled(
        !art_is_not_set);
  }

  bask_in_his_glory_action_->setVisible(static_cast<bool>(hypnotoad_));

  // show the menu
  menu_->popup(mapToGlobal(e->pos()));
}

void NowPlayingWidget::mouseReleaseEvent(QMouseEvent* e) {
  // Same behaviour as right-click > Show Fullsize
  if (e->button() == Qt::LeftButton && !aww_ && !hypnotoad_.get()) {
    ShowCover();
  }
}

void NowPlayingWidget::ShowAboveStatusBar(bool above) {
  QSettings s;
  s.beginGroup(kSettingsGroup);
  s.setValue("above_status_bar", above);

  emit ShowAboveStatusBarChanged(above);
}

bool NowPlayingWidget::show_above_status_bar() const {
  return above_statusbar_action_->isChecked();
}

void NowPlayingWidget::FitCoverWidth(bool fit) {
  fit_width_ = fit;
  UpdateHeight();
  update();

  QSettings s;
  s.beginGroup(kSettingsGroup);
  s.setValue("fit_cover_width", fit_width_);
}

void NowPlayingWidget::AllHail(bool hypnotoad) {
  if (hypnotoad) {
    hypnotoad_.reset(new QMovie(kHypnotoadPath, QByteArray(), this));
    connect(hypnotoad_.get(), SIGNAL(updated(const QRect&)), SLOT(update()));
    hypnotoad_->start();
    update();
  } else {
    hypnotoad_.reset();
    update();
  }
}

void NowPlayingWidget::EnableKittens(bool aww) {
  if (!kittens_ && aww) {
    kittens_ = new KittenLoader(this);
    app_->MoveToNewThread(kittens_);
    connect(kittens_, SIGNAL(ImageLoaded(quint64, QImage)),
            SLOT(KittenLoaded(quint64, QImage)));
    connect(kittens_, SIGNAL(ImageLoaded(quint64, QImage)),
            app_->network_remote(), SLOT(SendKitten(quint64, QImage)));
  }

  aww_ = aww;
}

void NowPlayingWidget::LoadCoverFromFile() {
  album_cover_choice_controller_->LoadCoverFromFile(&metadata_);
}

void NowPlayingWidget::LoadCoverFromURL() {
  album_cover_choice_controller_->LoadCoverFromURL(&metadata_);
}

void NowPlayingWidget::SearchForCover() {
  album_cover_choice_controller_->SearchForCover(&metadata_);
}

void NowPlayingWidget::SaveCoverToFile() {
  album_cover_choice_controller_->SaveCoverToFile(metadata_, original_);
}

void NowPlayingWidget::UnsetCover() {
  album_cover_choice_controller_->UnsetCover(&metadata_);
}

void NowPlayingWidget::ShowCover() {
  album_cover_choice_controller_->ToggleCover(metadata_);
}

void NowPlayingWidget::SearchCoverAutomatically() {
  QSettings s;
  s.beginGroup(kSettingsGroup);
  s.setValue(
      "search_for_cover_auto",
      album_cover_choice_controller_->search_cover_auto_action()->isChecked());

  // Search for cover automatically?
  GetCoverAutomatically();
}

void NowPlayingWidget::Bask() {
#if (QT_VERSION >= QT_VERSION_CHECK(5, 14, 0))
  QScreen* screen = QWidget::screen();
#else
  QScreen* screen =
      (window() && window()->windowHandle() ? window()->windowHandle()->screen()
                                            : QGuiApplication::primaryScreen());
#endif
  big_hypnotoad_.reset(new FullscreenHypnotoad);
  if (screen) big_hypnotoad_->setGeometry(screen->availableGeometry());
  big_hypnotoad_->showFullScreen();
}

void NowPlayingWidget::dragEnterEvent(QDragEnterEvent* e) {
  if (AlbumCoverChoiceController::CanAcceptDrag(e)) {
    e->acceptProposedAction();
  }

  QWidget::dragEnterEvent(e);
}

void NowPlayingWidget::dropEvent(QDropEvent* e) {
  album_cover_choice_controller_->SaveCover(&metadata_, e);

  QWidget::dropEvent(e);
}

bool NowPlayingWidget::GetCoverAutomatically() {
  // Search for cover automatically?
  bool search =
      album_cover_choice_controller_->search_cover_auto_action()->isChecked() &&
      !metadata_.has_manually_unset_cover() &&
      metadata_.art_automatic().isEmpty() && metadata_.art_manual().isEmpty() &&
      !metadata_.effective_albumartist().isEmpty() &&
      !metadata_.effective_album().isEmpty();

  if (search) {
    qLog(Debug) << "GetCoverAutomatically";
    downloading_covers_ = true;
    album_cover_choice_controller_->SearchCoverAutomatically(metadata_);

    // Show a spinner animation
    spinner_animation_.reset(new QMovie(":/spinner.gif", QByteArray(), this));
    connect(spinner_animation_.get(), SIGNAL(updated(const QRect&)),
            SLOT(update()));
    spinner_animation_->start();
    update();
  }

  return search;
}

void NowPlayingWidget::AutomaticCoverSearchDone() {
  downloading_covers_ = false;
  spinner_animation_.reset();
  update();
}