/**
  * @RDE_HEADER@
  * Gui Plugin for Free Space Monitor
  * $Id$
  * $HeadURL$
  * $Author$
  * Created by Mike Wille, SLTE, 2020-11-22
  */

#include "fsp_gui_plugin.h"

#include <LtsNotification/lts_notification.h>
#include <LtsSession/lts_session.h>
#include <LtsSession/lts_session_data.h>
#include <NGLLogger/NGLLoggerBootstrap.h>
#include <LtsWidgets/lts_message_dialog.h>
#include <LtsWidgets/lts_base_layout_widget.h>

#include <cmath>
#include <iostream>
#include <fstream>

#include <QTimer>
#include <QStorageInfo>
#include <QCoreApplication>
#include <QPainter>
#include <QImage>
#include <QGradient>

#include <QDebug>


namespace FreeSpace
{

std::shared_ptr<GuiPluginBase::Interface> GuiPlugin::createGuiInterface(LtsSession::LtsSession *session)
{
  return std::make_shared<InterfaceImpl>(session);
}


InterfaceImpl::InterfaceImpl(LtsSession::LtsSession *session)
  : GuiPluginBase::Interface(session, NGL::NGLLoggerBootstrap::getNGLRootLogger().getNGLLogger("FreeSpaceGui"))
{
  connect(m_session, &LtsSession::LtsSession::signalDoneInitializingSession, // workaround to only receive the signal once
          this, &InterfaceImpl::onInitDone);
}

void InterfaceImpl::onInitDone()
{
  disconnect(m_session, &LtsSession::LtsSession::signalDoneInitializingSession,
             this, nullptr); // workaround to only receive the signal once
}

QVector<LtsWidgets::PluginData> InterfaceImpl::getActions()
{
  QVector<LtsWidgets::PluginData> ret;
  LtsWidgets::PluginData plData;

  unsigned long dummy1;
  double dummy2;

  if (onStatusRAM(dummy1, dummy2))
  {
    // RAM
    plData.identifier = QLatin1String("CreateFreeRamNoti");
    plData.createInstant = LtsWidgets::CreateInstantType::CreateInstantAndDiscardAction;
    plData.directFunc = [this](const LtsWidgets::PluginData &)
    {
      m_notiStatusRam = m_session->createNotification(QStringLiteral("FreeRamMonitor"));
      m_notiStatusRam->setIcon(QIcon(QStringLiteral("icon:usedspace-100.svg")));
      //    m_noti->setAction([this]()
      //    {
      //      new LtsWidgets::LtsMessageDialogNew(m_session->baseLayout(), m_noti->tooltip(), tr("Current free disk space"));
      //    });

      slotCheckFreeRamStatus();

      QTimer *t = new QTimer(this);
      t->setInterval(5000);
      connect(t, &QTimer::timeout,
              this, &InterfaceImpl::slotCheckFreeRamStatus);
      t->start();
    };
    ret.append(plData);
  }


  // show free space indication only for MobileActionVehicle
  // (taken from pre_edit_gui_plugin.cpp with small adaptions)

  bool fakeMba = (LtsSessionData::LtsSessionData::getInstance()->debugFlagValue(QStringLiteral("MBA.Fake")) == QVariant(true));

  if (!fakeMba)
  {
    std::shared_ptr<AssetManagement::Interface::Dtc> asmDtc;
    if (!m_session->getDtc<AssetManagement::DataInterface>(asmDtc))
    {
      WARNING_LOG(m_logger) << "getDtc for AssetManagement::DataInterface failed.";
      return {};
    }

    bool isAAR = asmDtc->isAARWorkstation(LtsSession::LtsSession::workstationName());
    if (!isAAR)
    {
      DEBUG_LOG(m_logger) << "not a mba ws - no free space noti";
      return ret;
    }
  }
  else
    WARNING_LOG(m_logger) << "fake mba";

  plData.identifier = QLatin1String("CreateFreeSpaceNoti");
  plData.createInstant = LtsWidgets::CreateInstantType::CreateInstantAndDiscardAction;
  plData.directFunc = [this](const LtsWidgets::PluginData &)
  {
    m_notiStatusHdd = m_session->createNotification(QStringLiteral("FreeSpaceMonitor"));
    m_notiStatusHdd->setIcon(QIcon(QStringLiteral("icon:usedspace-100.svg")));
    m_notiStatusHdd->setAction([this]()
    {
      new LtsWidgets::LtsMessageDialogNew(m_session->baseLayout(), m_notiStatusHdd->tooltip(), tr("Current free disk space"));
    });

    slotCheckFreeSpaceStatus();

    QTimer *t = new QTimer(this);
    t->setInterval(10000);
    connect(t, &QTimer::timeout,
            this, &InterfaceImpl::slotCheckFreeSpaceStatus);
    t->start();
  };
  ret.append(plData);

  return ret;
}


// copied from osc_selftest.cpp and adapted
bool InterfaceImpl::onStatusHDD(quint64 &freeSpaceBytes, double &usedSpacePercent)
{
  QStorageInfo storage(QCoreApplication::applicationFilePath());
  if (storage.isValid() && storage.isReady())
  {
    quint64 freeBytesAvailable = storage.bytesAvailable();
    quint64 bytesAvailable = storage.bytesTotal();

    double percent = bytesAvailable ? 100.0 * freeBytesAvailable / bytesAvailable : 0;

    freeSpaceBytes = freeBytesAvailable;
    usedSpacePercent = 100.0 - percent;
    return true;
  }
  else
    return false;
}

bool InterfaceImpl::onStatusRAM(unsigned long &freeRamKbytes, double &usedRamPercent)
{
  freeRamKbytes = 0;
  usedRamPercent = 0.0;

  std::string key;
  std::ifstream meminfo("/proc/meminfo");

  if (!meminfo.is_open())
  {
    qWarning() << "cannot open /proc/meminfo";
    return false;
  }

  unsigned long memTotal = 0;
  unsigned long memAvailable = 0;

  while (meminfo >> key)
  {
    if (key == "MemTotal:")
      meminfo >> memTotal;
    else if (key == "MemAvailable:")
      meminfo >> memAvailable;

    meminfo.ignore(std::numeric_limits<std::streamsize>::max(), '\n'); // ignore rest of the line after the value we need
  }

  qDebug() << "MemTotal" << memTotal
           << "MemAvailable" << memAvailable;

  freeRamKbytes = memAvailable;
  usedRamPercent = static_cast<double>(memTotal - memAvailable) / static_cast<double>(memTotal) * 100.0;
  return true;
}

QImage renderRamImage(double usedRamPercent)
{
  int size = 100;
  QImage image(size, size, QImage::Format_ARGB32);
  image.fill(Qt::transparent);

  QPainter painter(&image);
  painter.setRenderHints(QPainter::Antialiasing | QPainter::SmoothPixmapTransform);

  QColor color{Qt::darkRed};
  if (usedRamPercent < 70.0)
    color = Qt::green;
  else if (usedRamPercent < 80.0)
    color = Qt::yellow;
  else if (usedRamPercent < 85.0)
    color = qRgb(213, 200, 0); // darkyellow
  else if (usedRamPercent < 90.0)
    color = qRgb(255, 165, 0); // orange
  else if (usedRamPercent < 95.0)
    color = Qt::red;

  QRadialGradient arcGradient(image.rect().center(), size * 0.6);
  arcGradient.setColorAt(1.0, Qt::transparent);
  arcGradient.setColorAt(0.0, color);

  painter.setBrush(QBrush(arcGradient));
  painter.setPen(QPen(Qt::NoPen)); // rect with no outter line
  painter.drawEllipse(image.rect());

  painter.end();

  return image;
}

void InterfaceImpl::slotCheckFreeRamStatus()
{
  if (!m_notiStatusRam)
    return;

  unsigned long freeRamKbytes;
  double usedRamPercent;
  if (!onStatusRAM(freeRamKbytes, usedRamPercent))
    return;

  m_notiStatusRam->setIcon(QPixmap::fromImage(renderRamImage(usedRamPercent)));

  QString statusText(tr("Free memory: %1 (%2% used)").arg(readableSize(freeRamKbytes * 1024)).arg(std::round(usedRamPercent))); // text output of free space in readable unit
  m_notiStatusRam->setToolTip(statusText);
}


void InterfaceImpl::slotCheckFreeSpaceStatus()
{
  if (!m_notiStatusHdd)
    return;

  double usedSpacePercent = 0.0;
  quint64 freeSpaceBytes = 0.0;

  bool success = onStatusHDD(freeSpaceBytes, usedSpacePercent);

  QString statusText;
  QString filename;

  if (!success)
  {
    statusText = tr("Error while reading disk space");
    filename = QStringLiteral("icon:usedspace-100.svg");
  }
  else
  {
    int usedDiskSpaceFile = 0;

    if (usedSpacePercent < 11) // this '11' thing ruins the easy 4-liner I had here first..
      usedDiskSpaceFile = 0;
    else if (usedSpacePercent < 21)
      usedDiskSpaceFile = 20;
    else if (usedSpacePercent < 41)
      usedDiskSpaceFile = 40;
    else if (usedSpacePercent < 61)
      usedDiskSpaceFile = 60;
    else if (usedSpacePercent < 81)
      usedDiskSpaceFile = 80;
    else
      usedDiskSpaceFile = 100;

    filename = QStringLiteral("icon:usedspace-%1.svg").arg(usedDiskSpaceFile);

    statusText = tr("Free disk space: %1 (%2% used)").arg(readableSize(freeSpaceBytes)).arg(std::round(usedSpacePercent)); // text output of free space in readable unit
  }

  QString tooltip(statusText);

  m_notiStatusHdd->setIcon(QIcon(filename));
  m_notiStatusHdd->setToolTip(tooltip);
}


// copied from osc_selftest.cpp
QString InterfaceImpl::readableSize(quint64 bytes) const
{
  if (bytes > TB)
    return QStringLiteral("%1 TB").arg((double) bytes / TB, 0, 'f', 2);
  else if (bytes > GB)
    return QStringLiteral("%1 GB").arg((double) bytes / GB, 0, 'f', 2);
  else if (bytes > MB)
    return QStringLiteral("%1 MB").arg((double) bytes / MB, 0, 'f', 2);
  else if (bytes > KB)
    return QStringLiteral("%1 KB").arg((double) bytes / KB, 0, 'f', 2);
  else
    return QStringLiteral("%1 Bytes").arg(bytes);
}


} // namespace FreeSpace