/*
    This file is part of KOrganizer.
    Copyright (c) 2000,2001 Cornelius Schumacher <schumacher@kde.org>
    Copyright (c) 2004 David Faure <faure@kde.org>
    Copyright (C) 2004 Reinhold Kainhofer <reinhold@kainhofer.com>

    This program 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 2 of the License, or
    (at your option) any later version.

    This program 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 this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

    As a special exception, permission is given to link this program
    with any edition of TQt, and distribute the resulting executable,
    without including the source code for TQt in the source distribution.
*/

#include "eventarchiver.h"
#include <kglobal.h>
#include <klocale.h>
#include <ktempfile.h>
#include <kio/netaccess.h>
#include <kglobal.h>
#include <libkcal/filestorage.h>
#include <libkcal/calendarlocal.h>
#include <libkcal/calendar.h>
#include <kmessagebox.h>
#include <kdebug.h>
#include "koprefs.h"

EventArchiver::EventArchiver( TQObject* tqparent, const char* name )
 : TQObject( tqparent, name )
{
}

EventArchiver::~EventArchiver()
{
}

void EventArchiver::runOnce( Calendar* calendar, const TQDate& limitDate, TQWidget* widget )
{
  run( calendar, limitDate, widget, true, true );
}

void EventArchiver::runAuto( Calendar* calendar, TQWidget* widget, bool withGUI )
{
  TQDate limitDate( TQDate::tqcurrentDate() );
  int expiryTime = KOPrefs::instance()->mExpiryTime;
  switch (KOPrefs::instance()->mExpiryUnit) {
  case KOPrefs::UnitDays: // Days
    limitDate = limitDate.addDays( -expiryTime );
    break;
  case KOPrefs::UnitWeeks: // Weeks
    limitDate = limitDate.addDays( -expiryTime*7 );
    break;
  case KOPrefs::UnitMonths: // Months
    limitDate = limitDate.addMonths( -expiryTime );
    break;
  default:
    return;
  }
  run( calendar, limitDate, widget, withGUI, false );
}

void EventArchiver::run( Calendar* calendar, const TQDate& limitDate, TQWidget* widget, bool withGUI,
                         bool errorIfNone )
{
  // We need to use rawEvents, otherwise events hidden by filters will not be archived.
  Incidence::List incidences;
  Event::List events;
  Todo::List todos;
  Journal::List journals;

  if ( KOPrefs::instance()->mArchiveEvents ) {
    events = calendar->rawEvents(
      TQDate( 1769, 12, 1 ),
      // #29555, also advertised by the "limitDate not included" in the class docu
      limitDate.addDays( -1 ),
      true );
  }
  if ( KOPrefs::instance()->mArchiveTodos ) {
    Todo::List t = calendar->rawTodos();
    Todo::List::ConstIterator it;
    for( it = t.begin(); it != t.end(); ++it ) {
      const bool todoComplete = (*it) &&
                                (*it)->isCompleted() &&
                                ( (*it)->completed().date() < limitDate );

      if ( todoComplete && !isSubTreeComplete( *it, limitDate ) ) {
        // The to-do is complete but some sub-todos are not.
        KMessageBox::information(
          widget,
          i18n( "Unable to archive to-do \"%1\" because at least one of its "
                "sub-to-dos does not meet the archival requirements." ).arg( (*it)->summary() ),
          i18n( "Archive To-do" ),
          "UncompletedChildrenArchiveTodos" );
      } else if ( todoComplete ) {
        todos.append( *it );
      }
    }
  }

  incidences = Calendar::mergeIncidenceList( events, todos, journals );


  kdDebug(5850) << "EventArchiver: archiving incidences before " << limitDate << " -> "
                << incidences.count() << " incidences found." << endl;
  if ( incidences.isEmpty() ) {
    if ( withGUI && errorIfNone ) {
      KMessageBox::information(
        widget,
        i18n( "There are no incidences available to archive before the specified cut-off date %1. "
              "Archiving will not be performed." ).arg( KGlobal::locale()->formatDate( limitDate ) ),
        "ArchiverNoIncidences" );
    }
    return;
  }


  switch ( KOPrefs::instance()->mArchiveAction ) {
  case KOPrefs::actionDelete:
    deleteIncidences( calendar, limitDate, widget, incidences, withGUI );
    break;
  case KOPrefs::actionArchive:
    archiveIncidences( calendar, limitDate, widget, incidences, withGUI );
    break;
  }
}

void EventArchiver::deleteIncidences( Calendar* calendar, const TQDate& limitDate, TQWidget* widget, const Incidence::List& incidences, bool withGUI )
{
  TQStringList incidenceStrs;
  Incidence::List::ConstIterator it;
  for( it = incidences.begin(); it != incidences.end(); ++it ) {
    incidenceStrs.append( (*it)->summary() );
  }

  if ( withGUI ) {
    int result = KMessageBox::warningContinueCancelList(
      widget, i18n("Delete all items before %1 without saving?\n"
                 "The following items will be deleted:")
      .arg(KGlobal::locale()->formatDate(limitDate)), incidenceStrs,
		 i18n("Delete Old Items"),KStdGuiItem::del());
    if (result != KMessageBox::Continue)
      return;
  }
  for( it = incidences.begin(); it != incidences.end(); ++it ) {
    calendar->deleteIncidence( *it );
  }
  emit eventsDeleted();
}

void EventArchiver::archiveIncidences( Calendar* calendar, const TQDate& /*limitDate*/, TQWidget* widget, const Incidence::List& incidences, bool /*withGUI*/)
{
  FileStorage storage( calendar );

  // Save current calendar to disk
  KTempFile tmpFile;
  tmpFile.setAutoDelete(true);
  storage.setFileName( tmpFile.name() );
  if ( !storage.save() ) {
    kdDebug(5850) << "EventArchiver::archiveEvents(): Can't save calendar to temp file" << endl;
    return;
  }

  // Duplicate current calendar by loading in new calendar object
  CalendarLocal archiveCalendar( KOPrefs::instance()->mTimeZoneId );

  FileStorage archiveStore( &archiveCalendar );
  archiveStore.setFileName( tmpFile.name() );
  if (!archiveStore.load()) {
    kdDebug(5850) << "EventArchiver::archiveEvents(): Can't load calendar from temp file" << endl;
    return;
  }

  // Strip active events from calendar so that only events to be archived
  // remain. This is not really efficient, but there is no other easy way.
  TQStringList uids;
  Incidence::List allIncidences = archiveCalendar.rawIncidences();
  Incidence::List::ConstIterator it;
  for( it = incidences.begin(); it != incidences.end(); ++it ) {
    uids << (*it)->uid();
  }
  for( it = allIncidences.begin(); it != allIncidences.end(); ++it ) {
    if ( !uids.tqcontains( (*it)->uid() ) ) {
      archiveCalendar.deleteIncidence( *it );
    }
  }

  // Get or create the archive file
  KURL archiveURL( KOPrefs::instance()->mArchiveFile );
  TQString archiveFile;

  if ( KIO::NetAccess::exists( archiveURL, true, widget ) ) {
    if( !KIO::NetAccess::download( archiveURL, archiveFile, widget ) ) {
      kdDebug(5850) << "EventArchiver::archiveEvents(): Can't download archive file" << endl;
      return;
    }
    // Merge with events to be archived.
    archiveStore.setFileName( archiveFile );
    if ( !archiveStore.load() ) {
      kdDebug(5850) << "EventArchiver::archiveEvents(): Can't merge with archive file" << endl;
      return;
    }
  } else {
    archiveFile = tmpFile.name();
  }

  // Save archive calendar
  if ( !archiveStore.save() ) {
    KMessageBox::error(widget,i18n("Cannot write archive file %1.").arg( archiveStore.fileName() ));
    return;
  }

  // Upload if necessary
  KURL srcUrl;
  srcUrl.setPath(archiveFile);
  if (srcUrl != archiveURL) {
    if ( !KIO::NetAccess::upload( archiveFile, archiveURL, widget ) ) {
      KMessageBox::error(widget,i18n("Cannot write archive to final destination."));
      return;
    }
  }

  KIO::NetAccess::removeTempFile(archiveFile);

  // Delete archived events from calendar
  for( it = incidences.begin(); it != incidences.end(); ++it ) {
    calendar->deleteIncidence( *it );
  }
  emit eventsDeleted();
}

bool EventArchiver::isSubTreeComplete( const Todo *todo, const TQDate &limitDate,
                                       TQStringList checkedUids ) const
{
  if ( !todo || !todo->isCompleted() || todo->completed().date() >= limitDate ) {
    return false;
  }

  // This TQList is only to prevent infinit recursion
  if ( checkedUids.tqcontains( todo->uid() ) ) {
    // Probably will never happen, calendar.cpp checks for this
    kdWarning() << "To-do hierarchy loop detected!";
    return false;
  }

  checkedUids.append( todo->uid() );

  Incidence::List::ConstIterator it;
  const Incidence::List relations = todo->relations();

  for( it = relations.begin(); it != relations.end(); ++it ) {
    if ( (*it)->type() == "Todo" ) {
      const Todo *t = static_cast<const Todo*>( *it );
      if ( !isSubTreeComplete( t, limitDate, checkedUids ) ) {
        return false;
      }
    }
  }

  return true;
}

#include "eventarchiver.moc"