/*=============================================================================

  Library: CTK

  Copyright (c) German Cancer Research Center,
    Division of Medical and Biological Informatics

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.

=============================================================================*/

#include <QStringList>

#include "ctkPlugin.h"
#include "ctkPlugin_p.h"
#include "ctkPluginContext.h"
#include "ctkPluginContext_p.h"
#include "ctkPluginFrameworkUtil_p.h"
#include "ctkPluginArchive_p.h"
#include "ctkPluginFrameworkContext_p.h"
#include "ctkServices_p.h"
#include "ctkUtils.h"

//----------------------------------------------------------------------------
ctkPlugin::ctkPlugin()
: d_ptr(0)
{

}

//----------------------------------------------------------------------------
void ctkPlugin::init(ctkPluginPrivate* dd)
{
  if (d_ptr) throw ctkIllegalStateException("ctkPlugin already initialized");
  d_ptr = dd;
}

//----------------------------------------------------------------------------
void ctkPlugin::init(const QWeakPointer<ctkPlugin>& self,
                     ctkPluginFrameworkContext* fw,
                     QSharedPointer<ctkPluginArchive> pa)
{
  if (d_ptr) throw ctkIllegalStateException("ctkPlugin already initialized");
  d_ptr = new ctkPluginPrivate(self, fw, pa);
}

//----------------------------------------------------------------------------
ctkPlugin::~ctkPlugin()
{
  delete d_ptr;
}

//----------------------------------------------------------------------------
ctkPlugin::State ctkPlugin::getState() const
{
  Q_D(const ctkPlugin);
  return d->state;
}

//----------------------------------------------------------------------------
void ctkPlugin::start(const StartOptions& options)
{
  Q_D(ctkPlugin);

  if (d->state == UNINSTALLED)
  {
    throw ctkIllegalStateException("ctkPlugin is uninstalled");
  }

  // Initialize the activation; checks initialization of lazy
  // activation.

  //TODO 1: If activating or deactivating, wait a litle
  // we don't use mutliple threads to start plugins for now
  //waitOnActivation(lock, "ctkPlugin::start", false);

  //2: start() is idempotent, i.e., nothing to do when already started
  if (d->state == ACTIVE)
  {
    return;
  }

  //3: Record non-transient start requests.
  if ((options & START_TRANSIENT) == 0)
  {
    d->setAutostartSetting(options);
  }

  //4: Resolve plugin (if needed)
  d->getUpdatedState();

  //5: Eager?
  if ((options & START_ACTIVATION_POLICY) && !d->eagerActivation )
  {
    if (STARTING == d->state) return;
    d->state = STARTING;
    d->pluginContext.reset(new ctkPluginContext(this->d_func()));
    ctkPluginEvent pluginEvent(ctkPluginEvent::LAZY_ACTIVATION, d->q_ptr);
    d->fwCtx->listeners.emitPluginChanged(pluginEvent);
  }
  else
  {
    d->finalizeActivation();
  }
}

//----------------------------------------------------------------------------
void ctkPlugin::stop(const StopOptions& options)
{
  Q_D(ctkPlugin);

  const ctkRuntimeException* savedException = 0;

  //1:
  if (d->state == UNINSTALLED)
  {
    throw ctkIllegalStateException("ctkPlugin is uninstalled");
  }

  // 2: If an operation is in progress, wait a little
  d->waitOnOperation(&d->operationLock, "Plugin::stop", false);

  //3:
  if ((options & STOP_TRANSIENT) == 0)
  {
    d->ignoreAutostartSetting();
  }

  switch (d->state)
  {
  case INSTALLED:
  case RESOLVED:
  case STOPPING:
  case UNINSTALLED:
    //4:
    return;

  case ACTIVE:
  case STARTING: // Lazy start...
    savedException = d->stop0();
    break;
  };

  if (savedException != 0)
  {
    if (const ctkPluginException* pluginExc = dynamic_cast<const ctkPluginException*>(savedException))
    {
      ctkPluginException pe(*pluginExc);
      delete savedException;
      throw pe;
    }
    else
    {
      ctkRuntimeException re(*savedException);
      delete savedException;
      throw re;
    }
  }
}

//----------------------------------------------------------------------------
void ctkPlugin::update(const QUrl& updateLocation)
{
  Q_D(ctkPlugin);
  ctkPluginPrivate::Locker sync(&d->operationLock);
  const bool wasActive = d->state == ACTIVE;

  switch (d->getUpdatedState_unlocked())
  {
  case ACTIVE:
    stop(STOP_TRANSIENT);
    // Fall through
  case RESOLVED:
  case INSTALLED:
    // Load new plugin
    //secure.callUpdate0(this, in, wasActive);
    d->update0(updateLocation, wasActive);
    break;
  case STARTING:
    // Wait for RUNNING state, this doesn't happen now
    // since we are synchronized.
    throw ctkIllegalStateException("Plugin is in STARTING state");
  case STOPPING:
    // Wait for RESOLVED state, this doesn't happen now
    // since we are synchronized.
    throw ctkIllegalStateException("Plugin is in STOPPING state");
  case UNINSTALLED:
    throw ctkIllegalStateException("Plugin is in UNINSTALLED state");
  }
}

//----------------------------------------------------------------------------
void ctkPlugin::uninstall()
{
  Q_D(ctkPlugin);
  {
    ctkPluginPrivate::Locker sync(&d->operationLock);

    if (d->archive)
    {
      try
      {
        d->archive->setStartLevel(-2); // Mark as uninstalled
      }
      catch (...)
      { }
    }

    switch (d->state)
    {
    case UNINSTALLED:
      throw ctkIllegalStateException("Plugin is in UNINSTALLED state");

    case STARTING: // Lazy start
    case ACTIVE:
    case STOPPING:
    {
      const ctkRuntimeException* exception = 0;
      try
      {
        d->waitOnOperation(&d->operationLock, "ctkPlugin::uninstall", true);
        if (d->state & (ACTIVE | STARTING))
        {
          exception = d->stop0();
        }
      }
      catch (const ctkException& e)
      {
        // Force to install
        d->setStateInstalled(false);
        d->operationLock.wakeAll();
        exception = new ctkRuntimeException("Stopping plug-in failed", e);
      }
      d->operation.fetchAndStoreOrdered(ctkPluginPrivate::UNINSTALLING);
      if (exception != 0)
      {
        d->fwCtx->listeners.frameworkError(this->d_func()->q_func(), *exception);
        delete exception;
      }
    }
      // Fall through
    case RESOLVED:
    case INSTALLED:
      d->fwCtx->plugins->remove(d->location);
      if (d->operation.fetchAndAddOrdered(0) != ctkPluginPrivate::UNINSTALLING)
      {
        try
        {
          d->waitOnOperation(&d->operationLock, "Plugin::uninstall", true);
          d->operation.fetchAndStoreOrdered(ctkPluginPrivate::UNINSTALLING);
        }
        catch (const ctkPluginException& pe)
        {
          // Make sure that the context is invalid
          if (d->pluginContext != 0)
          {
            d->pluginContext->d_func()->invalidate();
            d->pluginContext.reset();
          }
          d->operation.fetchAndStoreOrdered(ctkPluginPrivate::UNINSTALLING);
          d->fwCtx->listeners.frameworkError(this->d_func()->q_func(), pe);
        }
      }

      d->state = INSTALLED;
      // TODO: use thread
      // bundleThread().bundleChanged(new BundleEvent(BundleEvent.UNRESOLVED, this));
      d->fwCtx->listeners.emitPluginChanged(ctkPluginEvent(ctkPluginEvent::UNRESOLVED, d->q_func()));
      d->cachedHeaders = getHeaders();
      d->pluginActivator = 0;
      d->state = UNINSTALLED;

      // Purge old archive
      if (d->archive)
      {
        d->archive->purge();
      }
      d->operation.fetchAndStoreOrdered(ctkPluginPrivate::IDLE);

      if (d->pluginDir.exists())
      {
        if (!ctk::removeDirRecursively(d->pluginDir.absolutePath()))
        {
          d->fwCtx->listeners.frameworkError(this->d_func()->q_func(), ctkRuntimeException("Failed to delete plugin data"));
        }
        d->pluginDir.setFile("");
      }

      // id, location and headers survive after uninstall.

      // There might be plug-in threads that are running start or stop
      // operations. This will wake them and give them a chance to terminate.
      d->operationLock.wakeAll();
      break;
    }
  }
  d->fwCtx->listeners.emitPluginChanged(ctkPluginEvent(ctkPluginEvent::UNINSTALLED, d->q_ptr));
}

//----------------------------------------------------------------------------
ctkPluginContext* ctkPlugin::getPluginContext() const
{
  //TODO security checks
  Q_D(const ctkPlugin);
  return d->pluginContext.data();
}

//----------------------------------------------------------------------------
long ctkPlugin::getPluginId() const
{
  Q_D(const ctkPlugin);
  return d->id;
}

//----------------------------------------------------------------------------
QString ctkPlugin::getLocation() const
{
  //TODO security
  Q_D(const ctkPlugin);
  return d->location;
}

//----------------------------------------------------------------------------
QHash<QString, QString> ctkPlugin::getHeaders()
{
  //TODO security
  Q_D(ctkPlugin);
  if (d->cachedRawHeaders.empty())
  {
    d->cachedRawHeaders = d->archive->getUnlocalizedAttributes();
  }

  if (d->state == UNINSTALLED)
  {
    return d->cachedHeaders;
  }

  //TODO use the embedded .qm files to localize header values
  return d->cachedRawHeaders;
}

//----------------------------------------------------------------------------
QString ctkPlugin::getSymbolicName() const
{
  Q_D(const ctkPlugin);
  return d->symbolicName;
}

//----------------------------------------------------------------------------
QStringList ctkPlugin::getResourceList(const QString& path) const
{
  Q_D(const ctkPlugin);
  return d->archive->findResourcesPath(path);
}

//----------------------------------------------------------------------------
QStringList ctkPlugin::findResources(const QString& path,
                                     const QString& pattern, bool recurse) const
{
  Q_D(const ctkPlugin);
  return d->findResourceEntries(path, pattern, recurse);
}

//----------------------------------------------------------------------------
QByteArray ctkPlugin::getResource(const QString& path) const
{
  Q_D(const ctkPlugin);
  return d->archive->getPluginResource(path);
}

//----------------------------------------------------------------------------
ctkPluginLocalization ctkPlugin::getPluginLocalization(
  const QLocale& locale, const QString& base) const
{
  Q_D(const ctkPlugin);

  // There are five searching candidates possible:
  // base +
  //    "_" + language1 + "_" + country1 + ".qm"
  // or "_" + language1 + ".qm"
  // or "_" + language2 + "_" + country2 + ".qm"
  // or "_" + language2 + ".qm"
  // or ""  + ".qm"
  //
  // Where language1[_country1[_variation1]] is the requested locale,
  // and language2[_country2[_variation2]] is the default locale.

  QChar localeSep('_');
  QChar baseSep('_');

  QStringList searchCandidates;

  QStringList localeParts = locale.name().split(localeSep);
  QStringList defaultParts = QLocale().name().split(localeSep);

  searchCandidates << baseSep + localeParts[0] + localeSep + localeParts[1];
  searchCandidates << baseSep + localeParts[0];
  searchCandidates << baseSep + defaultParts[0] + localeSep + defaultParts[1];
  searchCandidates << baseSep + defaultParts[0];
  searchCandidates << "";

  QString localizationPath = base.left(base.lastIndexOf('/'));
  QStringList resourceList = this->getResourceList(localizationPath);

  foreach(QString resource, resourceList)
  {
    foreach(QString candidate, searchCandidates)
    {
      if (resource.endsWith(candidate + ".qm"))
      {
        return ctkPluginLocalization(localizationPath + '/' + resource, locale, d->q_ptr);
      }
    }
  }

  return ctkPluginLocalization();
}

//----------------------------------------------------------------------------
ctkVersion ctkPlugin::getVersion() const
{
  Q_D(const ctkPlugin);
  return d->version;
}

//----------------------------------------------------------------------------
QDebug operator<<(QDebug debug, ctkPlugin::State state)
{
  switch (state)
  {
  case ctkPlugin::UNINSTALLED:
    return debug << "UNINSTALLED";
  case ctkPlugin::INSTALLED:
    return debug << "INSTALLED";
  case ctkPlugin::RESOLVED:
    return debug << "RESOLVED";
  case ctkPlugin::STARTING:
    return debug << "STARTING";
  case ctkPlugin::STOPPING:
    return debug << "STOPPING";
  case ctkPlugin::ACTIVE:
    return debug << "ACTIVE";
  default:
    return debug << "unknown";
  }
}

//----------------------------------------------------------------------------
QDebug operator<<(QDebug debug, const ctkPlugin& plugin)
{
  debug.nospace() << "ctkPlugin[" << "id=" << plugin.getPluginId() <<
      ", state=" << plugin.getState() << ", loc=" << plugin.getLocation() <<
      ", symName=" << plugin.getSymbolicName() << "]";
  return debug.maybeSpace();
}

//----------------------------------------------------------------------------
QDebug operator<<(QDebug debug, ctkPlugin const * plugin)
{
  return operator<<(debug, *plugin);
}

//----------------------------------------------------------------------------
ctkLogStream& operator<<(ctkLogStream& stream, ctkPlugin const * plugin)
{
  stream << plugin->getSymbolicName();
  return stream;
}

//----------------------------------------------------------------------------
ctkLogStream& operator<<(ctkLogStream& stream, const QSharedPointer<ctkPlugin>& plugin)
{
  return operator<<(stream, plugin.data());
}