/*
 * @RDE_HEADER@
 * <short description>
 * $Id$
 * $HeadURL$
 * $Author$
 * Created by Malte Schröder, SLSE, 2016-06-08
 */

#include "aar_application.h"
#include "ui_aarApp.h"
#include "databases_model.h"

#include <ngldb/dbconnection.h>
#include <ngldb/nsqlquery.h>
#include <nglsettings/nglsettings_settings.h>
#include <ngltools/ngltools_filesystem.h>

#include <QMessageBox>
#include <QTimer>
#include <QMenu>
#include <QSettings>
#include <QDir>
#include <QThread>
#include <QScreen>
#include <QSqlError>

#define DEFAULT_DB "lts_ets_pro"

namespace AARApplication
{

AarApplication::AarApplication(QWidget *parent)
  : QMainWindow(parent)
  , m_ui(new Ui::AarApplication)
  , m_stopping(false)
  , m_proc(nullptr)
  , m_progressDialog(nullptr)
  , m_logger(getLogger("AarApplication"))
{
  setAttribute(Qt::WA_DeleteOnClose);

  m_ui->setupUi(this);

  const QList<QScreen*> &screenList = QGuiApplication::screens();
  m_widgets.reserve(screenList.size());
  for (QScreen *s : qAsConst(screenList))
  {
    QWidget *w = new QWidget(); // no parent
    w->setWindowFlags(Qt::Dialog | Qt::FramelessWindowHint);
    w->setGeometry(s->geometry());
    w->activateWindow();
    w->show();
    m_widgets.append(w);
  }

  m_databasesModel = new DatabasesModel(this);
  m_proxyModel = new DatabasesProxyModel(this);
  m_proxyModel->setSourceModel(m_databasesModel);
  m_ui->tableViewDatabases->setModel(m_proxyModel);

  connect(m_ui->pbClose, &QPushButton::clicked, this, &AarApplication::onClosedClicked);
  connect(m_ui->pbRemove, &QPushButton::clicked, this, &AarApplication::onRemoveClicked);
  connect(m_ui->pbActivate, &QPushButton::clicked, this, &AarApplication::onActivateClicked);
  connect(m_ui->pbActivateNetwork, &QPushButton::clicked, this, &AarApplication::onActivateNetworkClicked);

  connect(m_ui->tableViewDatabases->selectionModel(), &QItemSelectionModel::selectionChanged, this, &AarApplication::enaDisa);

  setWindowTitle(QLatin1String("AarApplication"));

  enaDisa();

  m_progressDialog = new QProgressDialog(this);

  m_progressDialog->setLabelText(tr("Stopping server software ..."));
  m_progressDialog->setMinimum(0);
  m_progressDialog->setMaximum(0);
  m_progressDialog->show();
  onStopApp();

}

AarApplication::~AarApplication()
{
  delete m_ui;
  delete m_databasesModel;
  delete m_progressDialog;

  for (QSqlDatabase db : qAsConst(m_dbMap))
    db.close();

  m_dbPostgres.close();

  if (m_proc)
    m_proc->deleteLater();

  qDeleteAll(m_widgets);
}

bool AarApplication::init()
{
  m_ui->lblStatus->setText(tr("No active database"));

  m_dbPostgres = DBConnection::open(m_logger,
                                    QStringLiteral("postgres"),
                                    QStringLiteral("postgres"),
                                    QStringLiteral("QPSQL"),
                                    QStringLiteral("localhost"),
                                    QStringLiteral("postgres"),
                                    QString(),
                                    QStringLiteral("localhost_postgres"));

  if (!m_dbPostgres.open())
  {
    ERROR_LOG(m_logger) << "Error opening postgres database" << m_dbPostgres.lastError().databaseText();
    return false;
  }

  NSqlQuery q(m_dbPostgres);

  QString stmt = QStringLiteral("SELECT datname FROM pg_database WHERE datname = '") + QStringLiteral(DEFAULT_DB) + QStringLiteral("'");

  if (!q.execAndFetch(stmt))
  {
    NOTICE_LOG(m_logger) << "Database does not exist: " << DEFAULT_DB;
  }
  else
  {
    QSqlDatabase db_lts = DBConnection::open(m_logger,
                                             QStringLiteral("ctc_sv"),
                                             QStringLiteral("ctc11de"),
                                             QStringLiteral("QPSQL"),
                                             QStringLiteral("localhost"),
                                             QStringLiteral(DEFAULT_DB),
                                             QString(),
                                             QStringLiteral("localhost_")+QStringLiteral(DEFAULT_DB));

    if (!db_lts.open())
    {
      ERROR_LOG(m_logger) << "Error opening database " << DEFAULT_DB << " : "<< db_lts.lastError().databaseText();
      m_dbPostgres.close();
      return false;
    }

    NSqlQuery ql(db_lts);

    stmt = QStringLiteral("SELECT id FROM exm.exercise");

    if (!ql.execAndFetch(stmt))
    {
      ERROR_LOG(m_logger) << "No entry for exercise found in database " << DEFAULT_DB;
    }
    else
    {
      int dbId = ql.value(0).toInt();
      db_lts.close();

      QString dbName = QStringLiteral("lts_db_") + QString::number(dbId);
      INFO_LOG(m_logger) << "New dbName for " << DEFAULT_DB << ": " << dbName;

      stmt = QStringLiteral("ALTER DATABASE ") + QStringLiteral(DEFAULT_DB) + QStringLiteral(" RENAME TO ") + dbName;

      if (!q.exec(stmt))
      {
        ERROR_LOG(m_logger) << "Error renaming database " << DEFAULT_DB << " : " << db_lts.lastError().databaseText();
        m_dbPostgres.close();
        return false;
      }
    }
  }

  stmt = QStringLiteral("SELECT datname FROM pg_database WHERE datname ilike 'lts_db_%';");

  if (!q.exec(stmt))
  {
    ERROR_LOG(m_logger) << "Error while reading dbnames from database";
    return false;
  }

  while (q.next())
  {
    QString dbName = q.value(0).toString();
    QSqlDatabase db = DBConnection::open(m_logger,
                                         QStringLiteral("ctc_sv"),
                                         QStringLiteral("ctc11de"),
                                         QStringLiteral("QPSQL"),
                                         QStringLiteral("localhost"),
                                         dbName,
                                         QString(),
                                         QStringLiteral("localhost_") + dbName);

    if (!db.open())
    {
      ERROR_LOG(m_logger) << "Error while opening database " << dbName << ", error: " << db.lastError().databaseText();
      continue;
    }

    m_databasesModel->initModel(db);
    m_dbMap.insert(dbName, db);
  }

  m_ui->tableViewDatabases->resizeColumnsToContents();

  return true;
}

void AarApplication::onClosedClicked()
{
  handleProcInit(QStringLiteral("/usr/bin/openbox"), {QStringLiteral("--exit")});
  m_proc->start();
  m_proc->waitForFinished();
  QThread::sleep(2);
  close();
}

void AarApplication::onRemoveClicked()
{
  disableButtons();

  m_databaseToRemove = m_databasesModel->getRowData(m_ui->tableViewDatabases->currentIndex().row());

  QString strMsg = QStringLiteral("Do you really want to remove the database '%1'?").arg (m_databaseToRemove.dbName);
  int result = QMessageBox::question(this, tr("Remove Database"), strMsg, QMessageBox::Yes | QMessageBox::No, QMessageBox::No);
  if (result == QMessageBox::No)
  {
    enableButtons();
    return;
  }

  DEBUG_LOG(m_logger) << "onRemoveClicked: dbName = " << m_databaseToRemove.dbName;
  QSqlDatabase db = m_dbMap.value(m_databaseToRemove.dbName);
  db.close();

  const QStringList args({QStringLiteral("-U"),
                          QStringLiteral("postgres"),
                          QStringLiteral("-h"),
                          QStringLiteral("localhost"),
                          m_databaseToRemove.dbName
                         });

  QString errStr;
  const QString exePath = NGL::postgresExecutablePath(QStringLiteral("dropdb"), errStr);
  if (!errStr.isEmpty())
    WARNING_LOG(m_logger) << errStr;

  handleProcInit(exePath, args);
  connect(m_proc, QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
          this, &AarApplication::onDropDbFinished);

  // start process
  m_proc->start();
}

void AarApplication::onActivateClicked()
{
  const QString fileName = QStringLiteral("/shd/CTC/WS/lts-cc.conf.org");

  WARNING_LOG(m_logger) << "FileName: " << fileName;
  QFile ltsConfig(fileName);

  if (ltsConfig.exists())
    ltsConfig.rename(QStringLiteral("/shd/CTC/WS/lts-cc.conf.org"), QStringLiteral("/shd/CTC/WS/lts-cc.conf"));

  Exercise ex = m_databasesModel->getRowData(m_ui->tableViewDatabases->currentIndex().row());

  QString strMsg = tr("Do you really want to activate database '%1'?").arg(ex.name);
  int result = QMessageBox::question(this, tr("Activate local database"), strMsg, QMessageBox::Yes | QMessageBox::No, QMessageBox::No);
  if (result == QMessageBox::No)
    return;

  INFO_LOG(m_logger) << "onActivateClicked: dbName = " << ex.dbName;

  QSqlDatabase db = m_dbMap.value(ex.dbName);
  db.close();

  NSqlQuery q(m_dbPostgres);

  QString stmt = QStringLiteral("ALTER DATABASE ") + ex.dbName + QStringLiteral(" RENAME TO ") + QStringLiteral(DEFAULT_DB);

  if (!q.exec(stmt))
    ERROR_LOG(m_logger) << "Error renaming " << ex.dbName << " to " << DEFAULT_DB << " "<< m_dbPostgres.lastError().databaseText();
  else
    INFO_LOG(m_logger) << "Database " << ex.dbName << " renamed to " << DEFAULT_DB;

  QString status = ex.name + QStringLiteral(" (") + ex.dbName + QStringLiteral(") ") + tr("active");
  m_ui->lblStatus->setText(status);
  onStartApp();
}

void AarApplication::onActivateNetworkClicked()
{
  onStopApp();
  //const QString fileName = QDir::homePath()+ QStringLiteral("/lts-cc.conf");

  const QString fileName = QStringLiteral("/shd/CTC/WS") + QStringLiteral("/lts-cc.conf");

  WARNING_LOG(m_logger) << "FileName: " << fileName;
  QFile ltsConfig(fileName);

  if (!ltsConfig.exists())
  {
    QMessageBox::critical(this, tr ("Activate network database"), tr("Network database active"), QMessageBox::Ok);
    m_ui->lblStatus->setText(tr("Network database active"));
    return;
  }

  ltsConfig.rename(QStringLiteral("/shd/CTC/WS/lts-cc.conf"), QStringLiteral("/shd/CTC/WS/lts-cc.conf.org"));
  m_ui->lblStatus->setText(tr("Network database active"));
}

void AarApplication::enaDisa()
{
  if (!m_ui)
    return;
  int selected = m_ui->tableViewDatabases->selectionModel()->selectedRows().size();

  m_ui->pbRemove->setEnabled(selected > 0);
  m_ui->pbActivate->setEnabled(selected > 0);
}

void AarApplication::onDropDbFinished(int exitCode, QProcess::ExitStatus exitStatus)
{
  INFO_LOG(m_logger) << "onDropDbFinished: exitCode: " << exitCode << ", exitStatus: " << exitStatus;

  static const QString s_title = tr("Remove Database");
  static const QString s_msgFailure = tr("Removing database failed.");
  static const QString s_msgSuccess = tr("Removing database successful.");

  if (exitCode > 0)
  {
    const QString str = QString::fromLocal8Bit(m_proc->readAllStandardError()) + QLatin1Char('\n') +
        QString::fromLocal8Bit(m_proc->readAllStandardOutput());
    ERROR_LOG(m_logger) << "Cannot drop database: " << str;
    QString msg = s_msgFailure;
    QString db0 = QLatin1String("ERROR:  database \"") + m_databaseToRemove.dbName + QLatin1String("\" does not exist");
    if (!str.contains(db0))
      msg += tr(" Database cannot be removed:\n%1.").arg(str);
    QMessageBox::critical(this, s_title, msg, QMessageBox::Ok);
  }
  else
  {
    m_databasesModel->onDataChanged(m_databaseToRemove, DataModification::eRemoved);
    QMessageBox::information(this, s_title, s_msgSuccess);
  }

  enableButtons();
}

void AarApplication::onErrorOccured(QProcess::ProcessError error)
{
  ERROR_LOG(m_logger) << "error: " << error;
}

void AarApplication::onStartApp()
{
  handleProcInit(QStringLiteral("ps"), {QStringLiteral("aux")});
  connect(m_proc, QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
          this, &AarApplication::onPsauxFinished);
  m_proc->start();
}


void AarApplication::onPsauxFinished()
{
  enableButtons();
  QByteArray output = m_proc->readAllStandardOutput();

  if (output.contains("svcServiceManagement"))
  {
    ERROR_LOG(m_logger) << "ServiceManagement already started";
  }
  else
  {
    ERROR_LOG(m_logger) << "Start svcServiceManagement";
    handleProcInit(QCoreApplication::applicationDirPath() + QStringLiteral("/svcServiceManagement"), {QStringLiteral("-z")});
    connect(m_proc, QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
            this, &AarApplication::onStartAppFinished);
    m_proc->start();
    m_proc->waitForFinished();
  }
}

void AarApplication::onStartAppFinished(int exitCode, QProcess::ExitStatus exitStatus)
{
  handleProcFinished(exitCode, exitStatus);
}

void AarApplication::onStopApp()
{
  disableButtons();
  handleProcInit(QStringLiteral("ps"), {QStringLiteral("aux")});
  m_proc->start();
  if (m_proc->waitForFinished())
    onPsauxStopFinished();
}

void AarApplication::onPsauxStopFinished()
{
  DEBUG_LOG(m_logger) << "IN onPsauxStopFinished";
  enableButtons();
  QByteArray output = m_proc->readAllStandardOutput();

  if (output.contains("svcServiceManagement"))
  {
    if (m_stopping)
    {
      QThread::sleep(3);
      onStopApp();
    }
    else
    {

      ERROR_LOG(m_logger) << "ServiceManagement started - stopping";

      handleProcInit(QCoreApplication::applicationDirPath() + QStringLiteral("/svcServiceManagement"), {QStringLiteral("-s")});
      connect(m_proc, QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
              this, &AarApplication::onStopAppFinished);
      m_proc->start();
      m_stopping = true;
    }
  }
  else
  {
    INFO_LOG(m_logger) << "ServiceManagement already stopped";
    m_stopping = false;
    m_progressDialog->hide();
  }

  m_proc->waitForFinished();
}

void AarApplication::onStopAppFinished(int exitCode, QProcess::ExitStatus exitStatus)
{
  if (m_stopping)
    onPsauxStopFinished();

  handleProcFinished(exitCode, exitStatus);
}

void AarApplication::handleProcInit(const QString &program, const QStringList &args)
{
  if (m_proc)
  {
    m_proc->disconnect(this);
    m_proc->deleteLater();
  }
  m_proc = new QProcess(this);
  NOTICE_LOG(m_logger) << "Starting process '" << program << "' with args '"
                       << args.join(QLatin1Char(' ')) << "'";

  m_proc->setProgram(program);
  m_proc->setArguments(args);
  connect(m_proc, &QProcess::errorOccurred, this, &AarApplication::onErrorOccured);
  disableButtons();
}

void AarApplication::handleProcFinished(int exitCode, QProcess::ExitStatus exitStatus)
{
  enableButtons();

  if (!m_proc)
    return;
  if (exitCode != 0 || exitStatus != 0)
  {
    QByteArray out = m_proc->readAllStandardError();
    if (!out.isEmpty())
      out += '\n';
    out += m_proc->readAllStandardOutput();
    ERROR_LOG(m_logger) << "Process finished - exitCode: " << exitCode << ", exitStatus = " << exitStatus << ", " << out;

    QMessageBox::critical(this,
                          tr ("Execute process"), tr("Error executing process, exitCode: %1, exitStatus: %2, output: %3")
                          .arg(exitCode).arg(exitStatus).arg(QString::fromLocal8Bit(out)),
                          QMessageBox::Ok);
  }
  m_proc->disconnect(this);
  m_proc->deleteLater();
  m_proc = nullptr;

  if (m_progressDialog)
    m_progressDialog->hide();
}


void AarApplication::enaDisaButtons(bool bEnable)
{
  {
    const QList<QPushButton*> l = findChildren<QPushButton*>();
    for (QPushButton *pb : l)
      pb->setEnabled(bEnable);
  }
  {
    const QList<QAction*> l = findChildren<QAction*>();
    for (QAction *a : l)
      a->setEnabled(bEnable);
  }
  if (bEnable)
    enaDisa();
}

} // namespace AarApplication