alarmcalendar.cpp

/*
 *  alarmcalendar.cpp  -  KAlarm calendar file access
 *  Program:  kalarm
 *  Copyright © 2001-2006,2009 by David Jarvie <djarvie@kde.org>
 *
 *  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.
 */
 
#include "kalarm.h"
#include <unistd.h>
#include <time.h>
 
#include <tqfile.h>
#include <tqtextstream.h>
#include <tqregexp.h>
#include <tqtimer.h>
 
#include <tdelocale.h>
#include <tdemessagebox.h>
#include <tdestandarddirs.h>
#include <kstaticdeleter.h>
#include <tdeconfig.h>
#include <tdeaboutdata.h>
#include <tdeio/netaccess.h>
#include <tdefileitem.h>
#include <tdetempfile.h>
#include <tdefiledialog.h>
#include <dcopclient.h>
#include <kdebug.h>
 
extern "C" {
#include <libical/ical.h>
}
 
#include <libkcal/vcaldrag.h>
#include <libkcal/vcalformat.h>
#include <libkcal/icalformat.h>
 
#include "calendarcompat.h"
#include "daemon.h"
#include "functions.h"
#include "kalarmapp.h"
#include "mainwindow.h"
#include "preferences.h"
#include "startdaytimer.h"
#include "alarmcalendar.moc"
 
using namespace KCal;
 
TQString AlarmCalendar::icalProductId()
{
    return TQString::fromLatin1("-//K Desktop Environment//NONSGML " KALARM_NAME " %1//EN").arg(KAlarm::currentCalendarVersionString());
}
 
static const KAEvent::Status eventTypes[AlarmCalendar::NCALS] = {
    KAEvent::ACTIVE, KAEvent::EXPIRED, KAEvent::DISPLAYING, KAEvent::TEMPLATE
};
static const TQString calendarNames[AlarmCalendar::NCALS] = {
    TQString::fromLatin1("calendar.ics"),
    TQString::fromLatin1("expired.ics"),
    TQString::fromLatin1("displaying.ics"),
    TQString::fromLatin1("template.ics")
};
static KStaticDeleter<AlarmCalendar> calendarDeleter[AlarmCalendar::NCALS];    // ensure that the calendar destructors are called
 
AlarmCalendar* AlarmCalendar::mCalendars[NCALS] = { 0, 0, 0, 0 };
 
 
/******************************************************************************
* Initialise the alarm calendars, and ensure that their file names are different.
* There are 4 calendars:
*  1) A user-independent one containing the active alarms;
*  2) A historical one containing expired alarms;
*  3) A user-specific one which contains details of alarms which are currently
*     being displayed to that user and which have not yet been acknowledged;
*  4) One containing alarm templates.
* Reply = true if success, false if calendar name error.
*/
bool AlarmCalendar::initialiseCalendars()
{
    TDEConfig* config = tdeApp->config();
    config->setGroup(TQString::fromLatin1("General"));
    TQString activeKey   = TQString::fromLatin1("Calendar");
    TQString expiredKey  = TQString::fromLatin1("ExpiredCalendar");
    TQString templateKey = TQString::fromLatin1("TemplateCalendar");
    TQString displayCal, activeCal, expiredCal, templateCal;
    calendarDeleter[ACTIVE].setObject(mCalendars[ACTIVE], createCalendar(ACTIVE, config, activeCal, activeKey));
    calendarDeleter[EXPIRED].setObject(mCalendars[EXPIRED], createCalendar(EXPIRED, config, expiredCal, expiredKey));
    calendarDeleter[DISPLAY].setObject(mCalendars[DISPLAY], createCalendar(DISPLAY, config, displayCal));
    calendarDeleter[TEMPLATE].setObject(mCalendars[TEMPLATE], createCalendar(TEMPLATE, config, templateCal, templateKey));
 
    TQString errorKey1, errorKey2;
    if (activeCal == displayCal)
        errorKey1 = activeKey;
    else if (expiredCal == displayCal)
        errorKey1 = expiredKey;
    else if (templateCal == displayCal)
        errorKey1 = templateKey;
    if (!errorKey1.isNull())
    {
        kdError(5950) << "AlarmCalendar::initialiseCalendars(): '" << errorKey1 << "' calendar name = display calendar name\n";
        TQString file = config->readPathEntry(errorKey1);
        KAlarmApp::displayFatalError(i18n("%1: file name not permitted: %2").arg(errorKey1).arg(file));
        return false;
    }
    if (activeCal == expiredCal)
    {
        errorKey1 = activeKey;
        errorKey2 = expiredKey;
    }
    else if (activeCal == templateCal)
    {
        errorKey1 = activeKey;
        errorKey2 = templateKey;
    }
    else if (expiredCal == templateCal)
    {
        errorKey1 = expiredKey;
        errorKey2 = templateKey;
    }
    if (!errorKey1.isNull())
    {
        kdError(5950) << "AlarmCalendar::initialiseCalendars(): calendar names clash: " << errorKey1 << ", " << errorKey2 << endl;
        KAlarmApp::displayFatalError(i18n("%1, %2: file names must be different").arg(errorKey1).arg(errorKey2));
        return false;
    }
    if (!mCalendars[ACTIVE]->valid())
    {
        TQString path = mCalendars[ACTIVE]->path();
        kdError(5950) << "AlarmCalendar::initialiseCalendars(): invalid name: " << path << endl;
        KAlarmApp::displayFatalError(i18n("Invalid calendar file name: %1").arg(path));
        return false;
    }
    return true;
}
 
/******************************************************************************
* Create an alarm calendar instance.
* If 'configKey' is non-null, the calendar will be converted to ICal format.
*/
AlarmCalendar* AlarmCalendar::createCalendar(CalID type, TDEConfig* config, TQString& writePath, const TQString& configKey)
{
    static TQRegExp vcsRegExp(TQString::fromLatin1("\\.vcs$"));
    static TQString ical = TQString::fromLatin1(".ics");
 
    if (configKey.isNull())
    {
        writePath = locateLocal("appdata", calendarNames[type]);
        return new AlarmCalendar(writePath, type);
    }
    else
    {
        TQString readPath = config->readPathEntry(configKey, locateLocal("appdata", calendarNames[type]));
        writePath = readPath;
        writePath.replace(vcsRegExp, ical);
        return new AlarmCalendar(readPath, type, writePath, configKey);
    }
}
 
/******************************************************************************
* Terminate access to all calendars.
*/
void AlarmCalendar::terminateCalendars()
{
    for (int i = 0;  i < NCALS;  ++i)
    {
        calendarDeleter[i].destructObject();
        mCalendars[i] = 0;
    }
}
 
/******************************************************************************
* Return a calendar, opening it first if not already open.
* Reply = calendar instance
*       = 0 if calendar could not be opened.
*/
AlarmCalendar* AlarmCalendar::calendarOpen(CalID id)
{
    AlarmCalendar* cal = mCalendars[id];
    if (!cal->mPurgeDays)
        return 0;     // all events are automatically purged from the calendar
    if (cal->open())
        return cal;
    kdError(5950) << "AlarmCalendar::calendarOpen(" << calendarNames[id] << "): open error\n";
    return 0;
}
 
/******************************************************************************
* Find and return the event with the specified ID.
* The calendar searched is determined by the calendar identifier in the ID.
*/
const KCal::Event* AlarmCalendar::getEvent(const TQString& uniqueID)
{
    if (uniqueID.isEmpty())
        return 0;
    CalID calID;
    switch (KAEvent::uidStatus(uniqueID))
    {
        case KAEvent::ACTIVE:      calID = ACTIVE;  break;
        case KAEvent::TEMPLATE:    calID = TEMPLATE;  break;
        case KAEvent::EXPIRED:     calID = EXPIRED;  break;
        case KAEvent::DISPLAYING:  calID = DISPLAY;  break;
        default:
            return 0;
    }
    AlarmCalendar* cal = calendarOpen(calID);
    if (!cal)
        return 0;
    return cal->event(uniqueID);
}
 
 
/******************************************************************************
* Constructor.
* If 'icalPath' is non-null, the file will be always be saved in ICal format.
* If 'configKey' is also non-null, that config file entry will be updated when
* the file is saved in ICal format.
*/
AlarmCalendar::AlarmCalendar(const TQString& path, CalID type, const TQString& icalPath,
                             const TQString& configKey)
    : mCalendar(0),
      mConfigKey(icalPath.isNull() ? TQString() : configKey),
      mType(eventTypes[type]),
      mPurgeDays(-1),      // default to not purging
      mOpen(false),
      mPurgeDaysQueued(-1),
      mUpdateCount(0),
      mUpdateSave(false)
{
    mUrl.setPath(path);       // N.B. constructor mUrl(path) doesn't work with UNIX paths
    mICalUrl.setPath(icalPath.isNull() ? path : icalPath);
    mVCal = (icalPath.isNull() || path != icalPath);    // is the calendar in ICal or VCal format?
}
 
AlarmCalendar::~AlarmCalendar()
{
    close();
}
 
/******************************************************************************
* Open the calendar file if not already open, and load it into memory.
*/
bool AlarmCalendar::open()
{
    if (mOpen)
        return true;
    if (!mUrl.isValid())
        return false;
 
    kdDebug(5950) << "AlarmCalendar::open(" << mUrl.prettyURL() << ")\n";
    if (!mCalendar)
        mCalendar = new CalendarLocal(TQString::fromLatin1("UTC"));
    mCalendar->setLocalTime();    // write out using local time (i.e. no time zone)
 
    // Check for file's existence, assuming that it does exist when uncertain,
    // to avoid overwriting it.
    if (!TDEIO::NetAccess::exists(mUrl, true, MainWindow::mainMainWindow()))
    {
        // The calendar file doesn't yet exist, so create it
        if (create())
            load();
    }
    else
    {
        // Load the existing calendar file
        if (load() == 0)
        {
            if (create())       // zero-length file - create a new one
                load();
        }
    }
    if (!mOpen)
    {
        delete mCalendar;
        mCalendar = 0;
    }
    return mOpen;
}
 
/******************************************************************************
* Private method to create a new calendar file.
* It is always created in iCalendar format.
*/
bool AlarmCalendar::create()
{
    if (mICalUrl.isLocalFile())
        return saveCal(mICalUrl.path());
    else
    {
        KTempFile tmpFile;
        return saveCal(tmpFile.name());
    }
}
 
/******************************************************************************
* Load the calendar file into memory.
* Reply = 1 if success
*       = 0 if zero-length file exists.
*       = -1 if failure to load calendar file
*       = -2 if instance uninitialised.
*/
int AlarmCalendar::load()
{
    if (!mCalendar)
        return -2;
 
    kdDebug(5950) << "AlarmCalendar::load(): " << mUrl.prettyURL() << endl;
    TQString tmpFile;
    if (!TDEIO::NetAccess::download(mUrl, tmpFile, MainWindow::mainMainWindow()))
    {
        kdError(5950) << "AlarmCalendar::load(): Load failure" << endl;
        KMessageBox::error(0, i18n("Cannot open calendar:\n%1").arg(mUrl.prettyURL()));
        return -1;
    }
    kdDebug(5950) << "AlarmCalendar::load(): --- Downloaded to " << tmpFile << endl;
    mCalendar->setTimeZoneId(TQString());   // default to the local time zone for reading
    bool loaded = mCalendar->load(tmpFile);
    mCalendar->setLocalTime();                 // write using local time (i.e. no time zone)
    if (!loaded)
    {
        // Check if the file is zero length
        TDEIO::NetAccess::removeTempFile(tmpFile);
        TDEIO::UDSEntry uds;
        TDEIO::NetAccess::stat(mUrl, uds, MainWindow::mainMainWindow());
        KFileItem fi(uds, mUrl);
        if (!fi.size())
            return 0;     // file is zero length
        kdError(5950) << "AlarmCalendar::load(): Error loading calendar file '" << tmpFile << "'" << endl;
        KMessageBox::error(0, i18n("Error loading calendar:\n%1\n\nPlease fix or delete the file.").arg(mUrl.prettyURL()));
        // load() could have partially populated the calendar, so clear it out
        mCalendar->close();
        delete mCalendar;
        mCalendar = 0;
        return -1;
    }
    if (!mLocalFile.isEmpty())
        TDEIO::NetAccess::removeTempFile(mLocalFile);   // removes it only if it IS a temporary file
    mLocalFile = tmpFile;
 
    CalendarCompat::fix(*mCalendar, mLocalFile);   // convert events to current KAlarm format for when calendar is saved
    mOpen = true;
    return 1;
}
 
/******************************************************************************
* Reload the calendar file into memory.
*/
bool AlarmCalendar::reload()
{
    if (!mCalendar)
        return false;
    kdDebug(5950) << "AlarmCalendar::reload(): " << mUrl.prettyURL() << endl;
    close();
    bool result = open();
    return result;
}
 
/******************************************************************************
* Save the calendar from memory to file.
* If a filename is specified, create a new calendar file.
*/
bool AlarmCalendar::saveCal(const TQString& newFile)
{
    if (!mCalendar || (!mOpen && newFile.isNull()))
        return false;
 
    kdDebug(5950) << "AlarmCalendar::saveCal(\"" << newFile << "\", " << mType << ")\n";
    TQString saveFilename = newFile.isNull() ? mLocalFile : newFile;
    if (mVCal  &&  newFile.isNull()  &&  mUrl.isLocalFile())
        saveFilename = mICalUrl.path();
    if (!mCalendar->save(saveFilename, new ICalFormat))
    {
        kdError(5950) << "AlarmCalendar::saveCal(" << saveFilename << "): failed.\n";
        KMessageBox::error(0, i18n("Failed to save calendar to\n'%1'").arg(mICalUrl.prettyURL()));
        return false;
    }
 
    if (!mICalUrl.isLocalFile())
    {
        if (!TDEIO::NetAccess::upload(saveFilename, mICalUrl, MainWindow::mainMainWindow()))
        {
            kdError(5950) << "AlarmCalendar::saveCal(" << saveFilename << "): upload failed.\n";
            KMessageBox::error(0, i18n("Cannot upload calendar to\n'%1'").arg(mICalUrl.prettyURL()));
            return false;
        }
    }
 
    if (mVCal)
    {
        // The file was in vCalendar format, but has now been saved in iCalendar format.
        // Save the change in the config file.
        if (!mConfigKey.isNull())
        {
            TDEConfig* config = tdeApp->config();
            config->setGroup(TQString::fromLatin1("General"));
            config->writePathEntry(mConfigKey, mICalUrl.path());
            config->sync();
        }
        mUrl  = mICalUrl;
        mVCal = false;
    }
 
    mUpdateSave = false;
    emit calendarSaved(this);
    return true;
}
 
/******************************************************************************
* Delete any temporary file at program exit.
*/
void AlarmCalendar::close()
{
    if (!mLocalFile.isEmpty())
    {
        TDEIO::NetAccess::removeTempFile(mLocalFile);   // removes it only if it IS a temporary file
        mLocalFile = "";
    }
    if (mCalendar)
    {
        mCalendar->close();
        delete mCalendar;
        mCalendar = 0;
    }
    mOpen = false;
}
 
/******************************************************************************
* Import alarms from an external calendar and merge them into KAlarm's calendar.
* The alarms are given new unique event IDs.
* Parameters: parent = parent widget for error message boxes
* Reply = true if all alarms in the calendar were successfully imported
*       = false if any alarms failed to be imported.
*/
bool AlarmCalendar::importAlarms(TQWidget* parent)
{
    KURL url = KFileDialog::getOpenURL(TQString::fromLatin1(":importalarms"),
                                       TQString::fromLatin1("*.vcs *.ics|%1").arg(i18n("Calendar Files")), parent);
    if (url.isEmpty())
    {
        kdError(5950) << "AlarmCalendar::importAlarms(): Empty URL" << endl;
        return false;
    }
    if (!url.isValid())
    {
        kdDebug(5950) << "AlarmCalendar::importAlarms(): Invalid URL" << endl;
        return false;
    }
    kdDebug(5950) << "AlarmCalendar::importAlarms(" << url.prettyURL() << ")" << endl;
 
    bool success = true;
    TQString filename;
    bool local = url.isLocalFile();
    if (local)
    {
        filename = url.path();
        if (!TDEStandardDirs::exists(filename))
        {
            kdDebug(5950) << "AlarmCalendar::importAlarms(): File '" << url.prettyURL() << "' not found" << endl;
            KMessageBox::error(parent, i18n("Could not load calendar '%1'.").arg(url.prettyURL()));
            return false;
        }
    }
    else
    {
        if (!TDEIO::NetAccess::download(url, filename, MainWindow::mainMainWindow()))
        {
            kdError(5950) << "AlarmCalendar::importAlarms(): Download failure" << endl;
            KMessageBox::error(parent, i18n("Cannot download calendar:\n%1").arg(url.prettyURL()));
            return false;
        }
        kdDebug(5950) << "--- Downloaded to " << filename << endl;
    }
 
    // Read the calendar and add its alarms to the current calendars
    CalendarLocal cal(TQString::fromLatin1("UTC"));
    cal.setLocalTime();    // write out using local time (i.e. no time zone)
    success = cal.load(filename);
    if (!success)
    {
        kdDebug(5950) << "AlarmCalendar::importAlarms(): error loading calendar '" << filename << "'" << endl;
        KMessageBox::error(parent, i18n("Could not load calendar '%1'.").arg(url.prettyURL()));
    }
    else
    {
        CalendarCompat::fix(cal, filename);
        bool saveActive   = false;
        bool saveExpired  = false;
        bool saveTemplate = false;
        AlarmCalendar* active  = activeCalendar();
        AlarmCalendar* expired = expiredCalendar();
        AlarmCalendar* templat = 0;
        AlarmCalendar* acal;
        Event::List events = cal.rawEvents();
        for (Event::List::ConstIterator it = events.begin();  it != events.end();  ++it)
        {
            const Event* event = *it;
            if (event->alarms().isEmpty()  ||  !KAEvent(*event).valid())
                continue;    // ignore events without alarms, or usable alarms
            KAEvent::Status type = KAEvent::uidStatus(event->uid());
            switch (type)
            {
                case KAEvent::ACTIVE:
                    acal = active;
                    saveActive = true;
                    break;
                case KAEvent::EXPIRED:
                    acal = expired;
                    saveExpired = true;
                    break;
                case KAEvent::TEMPLATE:
                    if (!templat)
                        templat = templateCalendarOpen();
                    acal = templat;
                    saveTemplate = true;
                    break;
                default:
                    continue;
            }
            if (!acal)
                continue;
 
            Event* newev = new Event(*event);
 
            // If there is a display alarm without display text, use the event
            // summary text instead.
            if (type == KAEvent::ACTIVE  &&  !newev->summary().isEmpty())
            {
                const Alarm::List& alarms = newev->alarms();
                for (Alarm::List::ConstIterator ait = alarms.begin();  ait != alarms.end();  ++ait)
                {
                    Alarm* alarm = *ait;
                    if (alarm->type() == Alarm::Display  &&  alarm->text().isEmpty())
                        alarm->setText(newev->summary());
                }
                newev->setSummary(TQString());   // KAlarm only uses summary for template names
            }
            // Give the event a new ID and add it to the calendar
            newev->setUid(KAEvent::uid(CalFormat::createUniqueId(), type));
            if (!acal->mCalendar->addEvent(newev))
                success = false;
        }
 
        // Save any calendars which have been modified
        if (saveActive)
            active->saveCal();
        if (saveExpired)
            expired->saveCal();
        if (saveTemplate)
            templat->saveCal();
    }
    if (!local)
        TDEIO::NetAccess::removeTempFile(filename);
    return success;
}
 
/******************************************************************************
* Flag the start of a group of calendar update calls.
* The purpose is to avoid multiple calendar saves during a group of operations.
*/
void AlarmCalendar::startUpdate()
{
    ++mUpdateCount;
}
 
/******************************************************************************
* Flag the end of a group of calendar update calls.
* The calendar is saved if appropriate.
*/
bool AlarmCalendar::endUpdate()
{
    if (mUpdateCount > 0)
        --mUpdateCount;
    if (!mUpdateCount)
    {
        if (mUpdateSave)
            return saveCal();
    }
    return true;
}
 
/******************************************************************************
* Save the calendar, or flag it for saving if in a group of calendar update calls.
*/
bool AlarmCalendar::save()
{
    if (mUpdateCount)
    {
        mUpdateSave = true;
        return true;
    }
    else
        return saveCal();
}
 
#if 0
/******************************************************************************
* If it is VCal format, convert the calendar URL to ICal and save the new URL
* in the config file.
*/
void AlarmCalendar::convertToICal()
{
    if (mVCal)
    {
        if (!mConfigKey.isNull())
        {
            TDEConfig* config = tdeApp->config();
            config->setGroup(TQString::fromLatin1("General"));
            config->writePathEntry(mConfigKey, mICalUrl.path());
            config->sync();
        }
        mUrl  = mICalUrl;
        mVCal = false;
    }
}
#endif
 
/******************************************************************************
* Set the number of days to keep alarms.
* Alarms which are older are purged immediately, and at the start of each day.
*/
void AlarmCalendar::setPurgeDays(int days)
{
    if (days != mPurgeDays)
    {
        int oldDays = mPurgeDays;
        mPurgeDays = days;
        if (mPurgeDays <= 0)
            StartOfDayTimer::disconnect(this);
        if (oldDays < 0 || (days >= 0 && days < oldDays))
        {
            // Alarms are now being kept for less long, so purge them
            if (open())
                slotPurge();
        }
        else if (mPurgeDays > 0)
            startPurgeTimer();
    }
}
 
/******************************************************************************
* Called at the start of each day by the purge timer.
* Purge all events from the calendar whose end time is longer ago than 'mPurgeDays'.
*/
void AlarmCalendar::slotPurge()
{
    purge(mPurgeDays);
    startPurgeTimer();
}
 
/******************************************************************************
* Purge all events from the calendar whose end time is longer ago than
* 'daysToKeep'. All events are deleted if 'daysToKeep' is zero.
*/
void AlarmCalendar::purge(int daysToKeep)
{
    if (mPurgeDaysQueued < 0  ||  daysToKeep < mPurgeDaysQueued)
        mPurgeDaysQueued = daysToKeep;
 
    // Do the purge once any other current operations are completed
    theApp()->processQueue();
}
 
/******************************************************************************
* This method must only be called from the main KAlarm queue processing loop,
* to prevent asynchronous calendar operations interfering with one another.
*
* Purge all events from the calendar whose end time is longer ago than 'daysToKeep'.
* All events are deleted if 'daysToKeep' is zero.
* The calendar must already be open.
*/
void AlarmCalendar::purgeIfQueued()
{
    if (mPurgeDaysQueued >= 0)
    {
        if (open())
        {
            kdDebug(5950) << "AlarmCalendar::purgeIfQueued(" << mPurgeDaysQueued << ")\n";
            bool changed = false;
            TQDate cutoff = TQDate::currentDate().addDays(-mPurgeDaysQueued);
            Event::List events = mCalendar->rawEvents();
            for (Event::List::ConstIterator it = events.begin();  it != events.end();  ++it)
            {
                Event* kcalEvent = *it;
                if (!mPurgeDaysQueued  ||  kcalEvent->created().date() < cutoff)
                {
                    mCalendar->deleteEvent(kcalEvent);
                    changed = true;
                }
            }
            if (changed)
            {
                saveCal();
                emit purged();
            }
            mPurgeDaysQueued = -1;
        }
    }
}
 
 
/******************************************************************************
* Start the purge timer to expire at the start of the next day (using the user-
* defined start-of-day time).
*/
void AlarmCalendar::startPurgeTimer()
{
    if (mPurgeDays > 0)
        StartOfDayTimer::connect(this, TQ_SLOT(slotPurge()));
}
 
/******************************************************************************
* Add the specified event to the calendar.
* If it is the active calendar and 'useEventID' is false, a new event ID is
* created. In all other cases, the event ID is taken from 'event'.
* 'event' is updated with the actual event ID.
* Reply = the KCal::Event as written to the calendar.
*/
Event* AlarmCalendar::addEvent(KAEvent& event, bool useEventID)
{
    if (!mOpen)
        return 0;
    TQString id = event.id();
    Event* kcalEvent = new Event;
    if (mType == KAEvent::ACTIVE)
    {
        if (id.isEmpty())
            useEventID = false;
        if (!useEventID)
            event.setEventID(kcalEvent->uid());
    }
    else
    {
        if (id.isEmpty())
            id = kcalEvent->uid();
        useEventID = true;
    }
    if (useEventID)
    {
        id = KAEvent::uid(id, mType);
        event.setEventID(id);
        kcalEvent->setUid(id);
    }
    event.updateKCalEvent(*kcalEvent, false, (mType == KAEvent::EXPIRED), true);
    mCalendar->addEvent(kcalEvent);
    event.clearUpdated();
    return kcalEvent;
}
 
/******************************************************************************
* Update the specified event in the calendar with its new contents.
* The event retains the same ID.
*/
void AlarmCalendar::updateEvent(const KAEvent& evnt)
{
    if (mOpen)
    {
        Event* kcalEvent = event(evnt.id());
        if (kcalEvent)
        {
            evnt.updateKCalEvent(*kcalEvent);
            evnt.clearUpdated();
            if (mType == KAEvent::ACTIVE)
                Daemon::savingEvent(evnt.id());
            return;
        }
    }
    if (mType == KAEvent::ACTIVE)
        Daemon::eventHandled(evnt.id(), false);
}
 
/******************************************************************************
* Delete the specified event from the calendar, if it exists.
* The calendar is then optionally saved.
*/
bool AlarmCalendar::deleteEvent(const TQString& eventID, bool saveit)
{
    if (mOpen)
    {
        Event* kcalEvent = event(eventID);
        if (kcalEvent)
        {
            mCalendar->deleteEvent(kcalEvent);
            if (mType == KAEvent::ACTIVE)
                Daemon::savingEvent(eventID);
            if (saveit)
                return save();
            return true;
        }
    }
    if (mType == KAEvent::ACTIVE)
        Daemon::eventHandled(eventID, false);
    return false;
}
 
/******************************************************************************
* Emit a signal to indicate whether the calendar is empty.
*/
void AlarmCalendar::emitEmptyStatus()
{
    emit emptyStatus(events().isEmpty());
}
 
/******************************************************************************
* Return the event with the specified ID.
*/
KCal::Event* AlarmCalendar::event(const TQString& uniqueID)
{
    return mCalendar ?  mCalendar->event(uniqueID) : 0;
}
 
/******************************************************************************
* Return all events in the calendar which contain usable alarms.
*/
KCal::Event::List AlarmCalendar::events()
{
    if (!mCalendar)
        return KCal::Event::List();
    KCal::Event::List list = mCalendar->rawEvents();
    KCal::Event::List::Iterator it = list.begin();
    while (it != list.end())
    {
        KCal::Event* event = *it;
        if (event->alarms().isEmpty()  ||  !KAEvent(*event).valid())
            it = list.remove(it);
        else
            ++it;
    }
    return list;
}
 
/******************************************************************************
* Return all events which have alarms falling within the specified time range.
*/
Event::List AlarmCalendar::eventsWithAlarms(const TQDateTime& from, const TQDateTime& to)
{
    kdDebug(5950) << "AlarmCalendar::eventsWithAlarms(" << from.toString() << " - " << to.toString() << ")\n";
    Event::List evnts;
    TQDateTime dt;
    Event::List allEvents = events();   // ignore events without usable alarms
    for (Event::List::ConstIterator it = allEvents.begin();  it != allEvents.end();  ++it)
    {
        Event* e = *it;
        bool recurs = e->doesRecur();
        int  endOffset = 0;
        bool endOffsetValid = false;
        const Alarm::List& alarms = e->alarms();
        for (Alarm::List::ConstIterator ait = alarms.begin();  ait != alarms.end();  ++ait)
        {
            Alarm* alarm = *ait;
            if (alarm->enabled())
            {
                if (recurs)
                {
                    if (alarm->hasTime())
                        dt = alarm->time();
                    else
                    {
                        // The alarm time is defined by an offset from the event start or end time.
                        // Find the offset from the event start time, which is also used as the
                        // offset from the recurrence time.
                        int offset = 0;
                        if (alarm->hasStartOffset())
                            offset = alarm->startOffset().asSeconds();
                        else if (alarm->hasEndOffset())
                        {
                            if (!endOffsetValid)
                            {
                                endOffset = e->hasDuration() ? e->duration() : e->hasEndDate() ? e->dtStart().secsTo(e->dtEnd()) : 0;
                                endOffsetValid = true;
                            }
                            offset = alarm->endOffset().asSeconds() + endOffset;
                        }
                        // Adjust the 'from' date/time and find the next recurrence at or after it
                        TQDateTime pre = from.addSecs(-offset - 1);
                        if (e->doesFloat()  &&  pre.time() < Preferences::startOfDay())
                            pre = pre.addDays(-1);    // today's recurrence (if today recurs) is still to come
                        dt = e->recurrence()->getNextDateTime(pre);
                        if (!dt.isValid())
                            continue;
                        dt = dt.addSecs(offset);
                    }
                }
                else
                    dt = alarm->time();
                if (dt >= from  &&  dt <= to)
                {
                    kdDebug(5950) << "AlarmCalendar::events() '" << e->summary()
                                  << "': " << dt.toString() << endl;
                    evnts.append(e);
                    break;
                }
            }
        }
    }
    return evnts;
}